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1

Methane and Nitrous Oxide Emissions from Rice-Duck and Rice-Fish Complex Ecosystems and the Evaluation of Their Economic Significance  

Microsoft Academic Search

Rice-duck (RD) and rice-fish (RF) ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane (CH4) and nitrous oxide (N2O) emissions and their economic value from these two ecosystems can provide theoretical and practical basis for further development and utilization of these classical agricultural techniques. CH4 and N2O emissions from RD

Wei-ling YUAN; Cou-gui CAO; Cheng-fang LI; Ming ZHAN; Ming-li CAI; Jin-ping WANG

2009-01-01

2

Rice protein 16KD--a major allergen in rice grain extract.  

PubMed

The allergenic activity of Rice protein 16 KD (RP16KD) isolated from water soluble rice proteins was examined by radioallergosorbent test (RAST), RAST inhibition and histamine release assay. All of the 31 sera which showed positive RAST values for rice grain extract were positive for RP16KD RAST. Furthermore, there was a significant correlation (r = 0.56, p less than 0.01) between these RAST values. PR16KD effectively inhibited IgE binding to the rice grain extract disc in RAST inhibition assays using 4 sera with positive RAST values for both antigens. In 17 subjects with positive RAST values for rice grain extract, a significant positive correlation (r = 0.53, p less than 0.05) was found between the maximum percent histamine releases from their leukocytes by rice grain extract and RP16KD. These data strongly suggest that RP16KD is one of the major allergens of rice grain. PMID:1722390

Urisu, A; Wada, E; Kondo, Y; Horiba, F; Tsuruta, M; Yasaki, T; Yamada, K; Masuda, S; Komada, H; Yamada, M

1991-11-01

3

Major flood disturbance alters river ecosystem evolution  

NASA Astrophysics Data System (ADS)

Floods, major formative drivers of channel and floodplain structure and associated riparian and in-stream communities, are increasing in intensity and magnitude with climate change in many regions of the world. However, predicting how floods will affect stream channels and their communities as climate changes is limited by a lack of long-term pre-flood baseline data sets across different organismal groups. Here we show salmon, macroinvertebrate and meiofauna communities, monitored for 30 years in a system evolving owing to glacier retreat, were modified significantly by a major rainfall event that caused substantial geomorphic change to the stream channel. Pink salmon, reduced to one-tenth of pre-flood spawner densities, recovered within two generations. Macroinvertebrate community structure was significantly different after the flood as some pioneer taxa, which had become locally extinct, recolonized whereas some later colonizers were eliminated. The trajectory of the macroinvertebrate succession was reset towards the community structure of 15 years earlier. Meiofaunal abundance recovered rapidly and richness increased post-flood with some previously unrecorded taxa colonizing. Biotic recovery was independent of geomorphological recovery. Markedly different responses according to the organismal group suggest caution is required when applying general aquatic ecosystem theories and concepts to predict flood events.

Milner, Alexander M.; Robertson, Anne L.; McDermott, Michael J.; Klaar, Megan J.; Brown, Lee E.

2013-02-01

4

Influence of the Asian monsoon on net ecosystem carbon exchange in two major ecosystems in Korea  

NASA Astrophysics Data System (ADS)

Considering the feedback in radiation, temperature, and soil moisture with alterations in rainfall patterns, the influence of the changing monsoon on Net Ecosystem CO2 Exchange (NEE) can be critical to the estimation of carbon balance in Asia. In this paper, we examined CO2 fluxes measured by the eddy covariance method from 2004 to 2008 in two major ecosystems in the KoFlux sites in Korea, i.e., the Gwangneung Deciduous forest (GDK) and the Haenam Farmland (HFK). Our objectives were to identify the repeatability of the mid-season depression of NEE encountered at the two sites based on the single-year observation, and to further scrutinize its cause, effect, and interannual variability by using multi-year observations. In both GDK and HFK sites, the mid-season depression of NEE was reproduced each year but with different timing, magnitude, and mechanism. At the GDK site, a predominant factor causing the mid-season depression was a decreased solar radiation and the consequent reduction in Gross Primary Productivity (GPP) during the summer monsoon period. At the HFK site, however, the monsoonal effect was less pronounced and the apparent mid-season depression was mainly a result of the management practices such as cultivation of spring barley and rice transplantation. Other flux observation sites in East Asia also showed a decline in radiation but with a lesser degree during the monsoon season, resulting in less pronounced depression in NEE. In our study, the observed depressions in NEE caused both GDK and HFK sites to become a weaker carbon sink or even a source in the middle of the growing season. On average, the GDK site (with maximum leaf area index of ~5) was a weak carbon sink with NEE of -84 gC m-2 y-1. Despite about 20% larger GPP (of 1321 gC m-2y-1) in comparison with the GDK site, the HFK site (with maximum leaf area index of 3-4) was a weaker carbon sink with NEE of -58 gC m-2 y-1 because of greater ecosystem respiration (of 1263 gC m-2 y-1). These NEE values were near the low end of the ranges reported in the literature for similar ecosystems in mid-latitudes. With the projected trends of the extended length of monsoon with more intensive rainfalls in East Asia, the observed delicate coupling between carbon and hydrological cycles may turn these key ecosystems into carbon neutral.

Kwon, H.; Kim, J.; Hong, J.; Lim, J.-H.

2010-05-01

5

Effects of fire on major forest ecosystem processes: an overview.  

PubMed

Fire and fire ecology are among the best-studied topics in contemporary ecosystem ecology. The large body of existing literature on fire and fire ecology indicates an urgent need to synthesize the information on the pattern of fire effects on ecosystem composition, structure, and functions for application in fire and ecosystem management. Understanding fire effects and underlying principles are critical to reduce the risk of uncharacteristic wildfires and for proper use of fire as an effective management tool toward management goals. This overview is a synthesis of current knowledge on major effects of fire on fire-prone ecosystems, particularly those in the boreal and temperate regions of the North America. Four closely related ecosystem processes in vegetation dynamics, nutrient cycling, soil and belowground process and water relations were discussed with emphases on fire as the driving force. Clearly, fire can shape ecosystem composition, structure and functions by selecting fire adapted species and removing other susceptible species, releasing nutrients from the biomass and improving nutrient cycling, affecting soil properties through changing soil microbial activities and water relations, and creating heterogeneous mosaics, which in turn, can further influence fire behavior and ecological processes. Fire as a destructive force can rapidly consume large amount of biomass and cause negative impacts such as post-fire soil erosion and water runoff, and air pollution; however, as a constructive force fire is also responsible for maintaining the health and perpetuity of certain fire-dependent ecosystems. Considering the unique ecological roles of fire in mediating and regulating ecosystems, fire should be incorporated as an integral component of ecosystems and management. However, the effects of fire on an ecosystem depend on the fire regime, vegetation type, climate, physical environments, and the scale of time and space of assessment. More ecosystem-specific studies are needed in future, especially those focusing on temporal and spatial variations of fire effects through long-term experimental monitoring and modeling. PMID:17147189

Chen, Zhong

2006-09-01

6

Temporal Dynamics of Bacterial and Fungal Communities in a Genetically Modified (GM) Rice Ecosystem  

Microsoft Academic Search

We assessed the temporal dynamics of bacterial and fungal communities in a soil ecosystem supporting genetically modified\\u000a (GM) rice (Oryza sativa L., ABC-TPSP; fusion of trehalose-6-phosphate synthase and phosphatase). Using terminal restriction fragment length polymorphism\\u000a analysis and real-time quantitative PCR, we compared bacterial and fungal communities in the soils underlying GM rice (ABC-TPSP),\\u000a and its host cultivar (Nakdong) during growing

Seung-Hoon Lee; Chang-Gi Kim; Hojeong Kang

2011-01-01

7

Fate of carbofuran in rice-fish model ecosystem —An international study  

Microsoft Academic Search

Work done in six nations by seven research groups on Carbofuran metabolism in rice-fish ecosystem is summarized. The following results have been obtained: (a) Soil acts as a sink for the pesticide and there is considerable metabolism in the soil; (b) There is no bioaccumulation\\/biomagnification by the fish used in the experiments, the residue levels in water being extremely low;

J. Jayaraman; L. P. Celino; K. H. Lee; R. B. Mohamad; J. Suns; N. Tayaputch; Z. Zhang

1989-01-01

8

STRAW MANAGEMENT AFFECTING METHANE EMISSIONS FROM DIFFERENT RICE ECOSYSTEMS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Emissions of the greenhouse gas methane from wetland rice fields are generally enhanced by organic inputs into the soil. This study investigates methane emissions and crop residue management at three sites: Los Banos (Philippines), Hangzhou (China), and Prachinburi (Thailand). In Los Banos, the co...

9

Nitrogen cycling in a flooded-soil ecosystem planted to rice ( Oryza sativa L.)  

Microsoft Academic Search

15N studies of various aspects of the nitrogen cycle in a flooded rice ecosystem on Crowley silt loam soil in Louisiana were reviewed to construct a mass balance model of the nitrogen cycle for this system. Nitrogen transformations modeled included 1) net ammonification (0.22 mg NH4+?N kg dry soil?1 day?1), 2) net nitrification (2.07 mg NO3??N kg?1 dry soil?1 day?1),

K. R. Reddy

1982-01-01

10

[QTL analysis for lodging resistance in rice using a DH population under lowland and upland ecosystems].  

PubMed

A DH (doubled haploid) population derived from a cross between Japonica upland rice IRAT109 and Japonica paddy rice Yuefu,was used in this study. Three culm traits, basal culm thickness(BCT), culm length (CL) and culm strength (CS), of DH lines and their parents under upland and lowland ecosystems at milk stage were studied. There were very significant positive correlations between BCT and CL, between BCT and CS and between CL and CS. Data from upland and lowland ecosystems were analyzed respectively and jointly, based on a constructed molecular linkage map(including 94 RFLP markers and 71 SSR markers and covering 1 535. 1cM)and the software QTLmapper version 1.0. A total of nine additive QTLs and five pairs of epistatic QTLs associated with BCT, CL, and CS were found by data analysis respectively. Six additive QTLs and six pairs of epistatic QTLs associated with BCT and CL were detected by data analysis jointly. Six additive QTLs and one pair of epistatic QTLs were detected by both methods. Two additive QTLs and two pairs of epistatic QTLs ( bct1a, c/9, c/6a-c/6c and cs5-cs12) for culm traits with general contributions of over 30% to phenotypic variation might be useful for upland rice lodging resistance molecular breeding under upland ecosystem. PMID:15473324

Mu, Ping; Li, Zi-Chao; Li, Chun-Ping; Zhang, Hong-Liang; Wang, Xiang-Kun

2004-07-01

11

Development and preliminary application of a triplex real-time polymerase chain reaction assay for evaluating predation on three planthoppers in a rice ecosystem.  

PubMed

A multiplex real-time quantitative polymerase chain reaction (PCR) assay was developed to simultaneously detect the DNA of three rice planthoppers, that is, Sogatella furcifera (Horváth) (white-backed planthopper), Nilaparvata lugens (Stål) (brown planthopper) and Laodelphax striatellus (Fallén) (small brown planthopper), in the gut of their predators. The sets of primers and ALLGlo probes were targeted to the regions of internal transcribed spacer 2 (ITS2) genes in nuclear ribosomal DNA (rDNA). The sensitivity, specificity and interference test for the multiplex real-time quantitative PCR assay were analysed. The assay's detection limits were 100, 1000 and 100 copies for the white-backed planthopper, the brown planthopper and the small brown planthopper, respectively. The specificity tests showed no cross-reactivity with genomic DNA from 30 other dominant herbivores, saprophagous insects and predators from rice ecosystem for each planthopper species. The assay was used in a preliminary study of predation events on the three planthoppers by three major spiders viz., Pardosa pseudoannulata (Bösenberg et Strand), Ummeliata insecticeps (Bösenberg et Strand) and Tetragnatha maxillosa Thorell which each differ in their preferred microhabitat as well as their predatory habits in rice field, and the results showed their predation on each planthopper species could be well evaluated using this method. Therefore, the multiplex real-time quantitative PCR assay provides a new tool to study the mechanisms of prey shifting and natural regulation of the three rice planthoppers by generalist predators in rice ecosystem. PMID:23711378

Wang, Guang-Hua; Wang, Xue-Qin; Qiao, Fei; Zhu, Zeng-Rong; Cheng, Jia-An

2013-05-27

12

Exploring the Ecological Significance of Microbial Diversity and Networking in the Rice Ecosystem  

Microsoft Academic Search

\\u000a Rice fields represent “hot spots of biodiversity” – encompassing a complicated network of aerobic, anaerobic and facultative\\u000a micro-organisms, whose interactions with the resident macro flora and fauna lead to unique and complex biochemical and physicochemical\\u000a reactions. In turn, these reactions fuel the major nutrient cycles. The dynamics of microbiological activity of rice soil,\\u000a especially in the rhizosphere, represents a model

Radha Prasanna; Lata Nain; Alok Kumar Pandey; Saswati Nayak

13

Characterization of the major fragance gene from an aromatic japonica rice and analysis of its diversity in Asian cultivated rice  

PubMed Central

In Asian cultivated rice (Oryza sativa L.), aroma is one of the most valuable traits in grain quality and 2-ACP is the main volatile compound contributing to the characteristic popcorn-like odour of aromatic rices. Although the major locus for grain fragrance (frg gene) has been described recently in Basmati rice, this gene has not been characterised in true japonica varieties and molecular information available on the genetic diversity and evolutionary origin of this gene among the different varieties is still limited. Here we report on characterisation of the frg gene in the Azucena variety, one of the few aromatic japonica cultivars. We used a RIL population from a cross between Azucena and IR64, a non-aromatic indica, the reference genomic sequence of Nipponbare (japonica) and 93–11 (indica) as well as an Azucena BAC library, to identify the major fragance gene in Azucena. We thus identified a betaine aldehyde dehydrogenase gene, badh2, as the candidate locus responsible for aroma, which presented exactly the same mutation as that identified in Basmati and Jasmine-like rices. Comparative genomic analyses showed very high sequence conservation between Azucena and Nipponbare BADH2, and a MITE was identified in the promotor region of the BADH2 allele in 93–11. The badh2 mutation and MITE were surveyed in a representative rice collection, including traditional aromatic and non-aromatic rice varieties, and strongly suggested a monophylogenetic origin of this badh2 mutation in Asian cultivated rices. Altogether these new data are discussed here in the light of current hypotheses on the origin of rice genetic diversity.

Bourgis, F.; Guyot, R.; Gherbi, H.; Tailliez, E.; Amabile, I.; Salse, J.; Lorieux, M.; Delseny, M.

2008-01-01

14

Changes of major terrestrial ecosystems in China since 1960  

NASA Astrophysics Data System (ADS)

Daily temperature and precipitation data since 1960 are selected from 735 weather stations that are scattered over China. After comparatively analyzing relative interpolation methods, gradient-plus-inverse distance squared (GIDS) is selected to create temperature surfaces and Kriging interpolation method is selected to create precipitation surfaces. Digital elevation model of China is combined into Holdridge Life Zone (HLZ) model on the basis of simulating relationships between temperature and elevation in different regions of China. HLZ model is operated on the created temperature and precipitation surfaces in ARC/INFO environment. Spatial pattern of major terrestrial ecosystems in China and its change in the four decades of 1960s, 1970s, 1980s and 1990s are analyzed in terms of results from operating HLZ model. The results show that HLZ spatial pattern in China has had a great change since 1960. For instance, nival area and subtropical thorn woodland had a rapid decrease on an average and they might disappear in 159 years and 96 years, respectively, if their areas would decrease at present rate. Alpine dry tundra and cool temperate scrub continuously increased in the four decades and the decadal increase rates are, respectively, 13.1% and 3.4%. HLZ patch connectivity has a continuous increase trend and HLZ diversity has a continuous decrease trend on the average. Warm temperate thorn steppe, subtropical wet forest and cool temperate wet forest shifted 1781.45 km, 1208.14 km and 977.43 km in the four decades, respectively. These HLZ types are more sensitive to climate change than other ones. These changes reflect the great effects of climate change on terrestrial ecosystems in China.

Yue, Tian Xiang; Fan, Ze Meng; Liu, Ji Yuan

2005-10-01

15

Major Ecosystems in China: Dynamics and Challenges for Sustainable Management  

Microsoft Academic Search

Ecosystems, though impacted by global environmental change, can also contribute to the adaptation and mitigation of such large\\u000a scale changes. Therefore, sustainable ecosystem management is crucial in reaching a sustainable future for the biosphere.\\u000a Based on the published literature and publicly accessible data, this paper discussed the status and trends of forest, grassland,\\u000a and wetland ecosystems in China that play

Yihe Lü; Bojie FuWei; Wei Wei; Xiubo Yu; Ranhao Sun

2011-01-01

16

Distribution of the Entomopathogenic Fungus Beauveria bassiana in Rice Ecosystems and Its Effect on Soil Enzymes.  

PubMed

Fungal entomopathogens, especially Beauveria bassiana, are often studied within the context of their use in biological pest control; however, there is limited knowledge of their distributions in host plants and soil ecosystem. We examined the distribution of B. bassiana and its influence on rice plants and paddy soils. B. bassiana could only be detected on the foliar surfaces of rice plants within 15 days under Bb-4 (7.5 × 10(4) conidia/mL) and Bb-7 (7.5 × 10(7) conidia/mL) treatments. The endophytic colonization of B. bassiana could not be found in stems, roots, or seeds of rice plants under Bb-4 and Bb-7 treatments. The fungus was found only in the leaves of rice plants under Bb-4 and Bb-7 treatments at 15 days after inoculation. Moreover, B. bassiana was absent from paddy soils under Bb-4 and Bb-7 treatments at all times. Enzyme activity (urease and phosphatase) in the paddy soils of Bb-4 and Bb-7 treatments showed no significant difference from the control. It is possible that B. bassiana was not able to colonize paddy soil. Detailed understanding of distribution and ecological interactions of B. bassiana is helpful for understanding and predicting the effects of fungal entomopathogens on host populations, and the interactions among fungal entomopathogens and other organisms in the community. PMID:23794015

Jia, Yong; Zhou, Jia-Yu; He, Jia-Xi; Du, Wei; Bu, Yuan-Qing; Liu, Chang-Hong; Dai, Chuan-Chao

2013-06-21

17

A major QTL controlling deep rooting on rice chromosome 4.  

PubMed

Drought is the most serious abiotic stress that hinders rice production under rainfed conditions. Breeding for deep rooting is a promising strategy to improve the root system architecture in shallow-rooting rice cultivars to avoid drought stress. We analysed the quantitative trait loci (QTLs) for the ratio of deep rooting (RDR) in three F2 mapping populations derived from crosses between each of three shallow-rooting varieties ('ARC5955', 'Pinulupot1', and 'Tupa729') and a deep-rooting variety, 'Kinandang Patong'. In total, we detected five RDR QTLs on chromosomes 2, 4, and 6. In all three populations, QTLs on chromosome 4 were found to be located at similar positions; they explained from 32.0% to 56.6% of the total RDR phenotypic variance. This suggests that one or more key genetic factors controlling the root growth angle in rice is located in this region of chromosome 4. PMID:24154623

Uga, Yusaku; Yamamoto, Eiji; Kanno, Noriko; Kawai, Sawako; Mizubayashi, Tatsumi; Fukuoka, Shuichi

2013-10-24

18

A major QTL controlling deep rooting on rice chromosome 4  

PubMed Central

Drought is the most serious abiotic stress that hinders rice production under rainfed conditions. Breeding for deep rooting is a promising strategy to improve the root system architecture in shallow-rooting rice cultivars to avoid drought stress. We analysed the quantitative trait loci (QTLs) for the ratio of deep rooting (RDR) in three F2 mapping populations derived from crosses between each of three shallow-rooting varieties (‘ARC5955', ‘Pinulupot1', and ‘Tupa729') and a deep-rooting variety, ‘Kinandang Patong'. In total, we detected five RDR QTLs on chromosomes 2, 4, and 6. In all three populations, QTLs on chromosome 4 were found to be located at similar positions; they explained from 32.0% to 56.6% of the total RDR phenotypic variance. This suggests that one or more key genetic factors controlling the root growth angle in rice is located in this region of chromosome 4.

Uga, Yusaku; Yamamoto, Eiji; Kanno, Noriko; Kawai, Sawako; Mizubayashi, Tatsumi; Fukuoka, Shuichi

2013-01-01

19

Major Ecosystems in China: Dynamics and Challenges for Sustainable Management  

NASA Astrophysics Data System (ADS)

Ecosystems, though impacted by global environmental change, can also contribute to the adaptation and mitigation of such large scale changes. Therefore, sustainable ecosystem management is crucial in reaching a sustainable future for the biosphere. Based on the published literature and publicly accessible data, this paper discussed the status and trends of forest, grassland, and wetland ecosystems in China that play important roles in the ecological integrity and human welfare of the nation. Ecological degradation has been observed in these ecosystems at various levels and geographic locations. Biophysical (e.g., climate change) and socioeconomic factors (e.g., intensive human use) are the main reasons for ecosystem degradation with the latter factors serving as the dominant driving forces. The three broad categories of ecosystems in China have partially recovered from degradation thanks to large scale ecological restoration projects implemented in the last few decades. China, as the largest and most populated developing nation, still faces huge challenges regarding ecosystem management in a changing and globalizing world. To further improve ecosystem management in China, four recommendations were proposed, including: (1) advance ecosystem management towards an application-oriented, multidisciplinary science; (2) establish a well-functioning national ecological monitoring and data sharing mechanism; (3) develop impact and effectiveness assessment approaches for policies, plans, and ecological restoration projects; and (4) promote legal and institutional innovations to balance the intrinsic needs of ecological and socioeconomic systems. Any change in China's ecosystem management approach towards a more sustainable one will benefit the whole world. Therefore, international collaborations on ecological and environmental issues need to be expanded.

Lü, Yihe; Fu, Bojie; Wei, Wei; Yu, Xiubo; Sun, Ranhao

2011-07-01

20

Mapping two major effect grain dormancy QTL in rice  

Microsoft Academic Search

The intrachromosomal positions of the two grain dormancy quantitative trait loci (QTL) qSdn-1 (chromosome 1) and qSdn-5 (chromosome 5) were obtained from the segregation analysis of the advanced backcross populations derived from the cross between\\u000a rice (Oryza sativa L.) cultivars N22 (indica) and Nanjing35 (japonica). Marker-assisted selection (MAS) was applied to select derivatives carrying one or both of qSdn-1 and

Bingyue Lu; Kun Xie; Chunyan Yang; Songfeng Wang; Xi Liu; Long Zhang; Ling Jiang; Jianmin Wan

21

Gross ecosystem photosynthesis causes a diurnal pattern in methane emission from rice  

NASA Astrophysics Data System (ADS)

Understanding the relative contribution of environmental and substrate controls on rice paddy methanogenesis is critical for developing mechanistic models of landscape-scale methane (CH4) flux. A diurnal pattern in observed rice paddy CH4 flux has been attributed to fluctuations in soil temperature physically driving diffusive CH4 transport from the soil to atmosphere. Here we make direct landscape-scale measurements of carbon dioxide and CH4 fluxes and show that gross ecosystem photosynthesis (GEP) is the dominant cause of the diurnal pattern in CH4 flux, even after accounting for the effects of soil temperature. The time series of GEP and CH4 flux show strong spectral coherency throughout the rice growing season at the diurnal timescale, where the peak in GEP leads that of CH4 flux by 1.3 ± 0.08 hours. By applying the method of conditional Granger causality in the spectral domain, we demonstrated that the diurnal pattern in CH4 flux is primarily caused by GEP.

Hatala, Jaclyn A.; Detto, Matteo; Baldocchi, Dennis D.

2012-03-01

22

The LGU Extension Services in a Major Rice-Growing Area : The Case of Hagonoy, Davao del Sur  

Microsoft Academic Search

The province of Davao del Sur is considered one of the major rice-producing provinces of Region XI. It has been regarded as Mindanaos top rice-yielding province because of its municipalitys (Hagonoy) high yield performance. Hagonoys average rice yield of more than six tons per hectare has consistently been higher than the provincial average of a little more than five tons

Rosa Fe D. Hondrade

2007-01-01

23

A Major Ecosystem Shift in the Northern Bering Sea  

NASA Astrophysics Data System (ADS)

Until recently, northern Bering Sea ecosystems were characterized by extensive seasonal sea ice cover, high water column and sediment carbon production, and tight pelagic-benthic coupling of organic production. Here, we show that these ecosystems are shifting away from these characteristics. Changes in biological communities are contemporaneous with shifts in regional atmospheric and hydrographic forcing. In the past decade, geographic displacement of marine mammal population distributions has coincided with a reduction of benthic prey populations, an increase in pelagic fish, a reduction in sea ice, and an increase in air and ocean temperatures. These changes now observed on the shallow shelf of the northern Bering Sea should be expected to affect a much broader portion of the Pacific-influenced sector of the Arctic Ocean.

Grebmeier, Jacqueline M.; Overland, James E.; Moore, Sue E.; Farley, Ed V.; Carmack, Eddy C.; Cooper, Lee W.; Frey, Karen E.; Helle, John H.; McLaughlin, Fiona A.; McNutt, S. Lyn

2006-03-01

24

Differences among major taxa in the extent of ecological knowledge across four major ecosystems.  

PubMed

Existing knowledge shapes our understanding of ecosystems and is critical for ecosystem-based management of the world's natural resources. Typically this knowledge is biased among taxa, with some taxa far better studied than others, but the extent of this bias is poorly known. In conjunction with the publically available World Registry of Marine Species database (WoRMS) and one of the world's premier electronic scientific literature databases (Web of Science®), a text mining approach is used to examine the distribution of existing ecological knowledge among taxa in coral reef, mangrove, seagrass and kelp bed ecosystems. We found that for each of these ecosystems, most research has been limited to a few groups of organisms. While this bias clearly reflects the perceived importance of some taxa as commercially or ecologically valuable, the relative lack of research of other taxonomic groups highlights the problem that some key taxa and associated ecosystem processes they affect may be poorly understood or completely ignored. The approach outlined here could be applied to any type of ecosystem for analyzing previous research effort and identifying knowledge gaps in order to improve ecosystem-based conservation and management. PMID:22073172

Fisher, Rebecca; Knowlton, Nancy; Brainard, Russell E; Caley, M Julian

2011-11-02

25

Marine viruses--major players in the global ecosystem.  

PubMed

Viruses are by far the most abundant 'lifeforms' in the oceans and are the reservoir of most of the genetic diversity in the sea. The estimated 10(30) viruses in the ocean, if stretched end to end, would span farther than the nearest 60 galaxies. Every second, approximately 10(23) viral infections occur in the ocean. These infections are a major source of mortality, and cause disease in a range of organisms, from shrimp to whales. As a result, viruses influence the composition of marine communities and are a major force behind biogeochemical cycles. Each infection has the potential to introduce new genetic information into an organism or progeny virus, thereby driving the evolution of both host and viral assemblages. Probing this vast reservoir of genetic and biological diversity continues to yield exciting discoveries. PMID:17853907

Suttle, Curtis A

2007-10-01

26

Genetic variation in root morphology and microsatellite DNA loci in upland rice (Oryza sativa L.) from Vietnam  

Microsoft Academic Search

Drought is a major constraint to the productivity of rice in upland ecosystems. The rice root system plays an important role in the regulation of water uptake and extraction from deep soil layers. The aim of this research was to study the variation in root morphology and the genetic diversity in upland rice accessions. Thirty-three upland rice accessions originated from

N. D. Thanh; H. G. Zheng; N. V. Dong; L. N. Trinh; M. L. Ali; H. T. Nguyen

1999-01-01

27

An economical approach for d-lactic acid production utilizing unpolished rice from aging paddy as major nutrient source  

Microsoft Academic Search

In order to reduce the raw material cost of d-lactic acid fermentation, the unpolished rice from aging paddy was used as major nutrient source in this study. The unpolished rice saccharificate, wheat bran powder and yeast extract were employed as carbon source, nitrogen source and growth factors, respectively. Response surface methodology (RSM) was applied to optimize the dosages of medium

Zhengdong Lu; Mingbo Lu; Feng He; Longjiang Yu

2009-01-01

28

40 CFR Table 2c to Subpart Zzzz of... - Requirements for Existing Compression Ignition Stationary RICE Located at a Major Source of HAP...  

Code of Federal Regulations, 2011 CFR

...Existing Compression Ignition Stationary RICE Located at a Major Source of HAP Emissions and Existing Spark Ignition Stationary RICE ⤠500 HP Located at a Major Source of...Existing Compression Ignition Stationary RICE Located at a Major Source of HAP...

2011-07-01

29

Metabolite Profiling—A Fractionation Method for Analysis of Major and Minor Compounds in Rice Grains  

Microsoft Academic Search

Cereal Chem. 79(2):215-221 A metabolite profiling methodology was developed using rice as model crop. The approach is based on consecutive extraction of lipids and polar compounds and subsequent fractionations of both extracts. Transesteri- fication-solid phase extraction (lipids) and selective hydrolysis of silylated derivatives (polar compounds) are applied to separate major from minor constituents. The method covers a broad spectrum of

Th. Frenzel; A. Miller; K.-H. Engel

2002-01-01

30

Rice  

Microsoft Academic Search

\\u000a Rice is a staple crop for more than half of the world's population. Rice improvement has achieved remarkable success in the\\u000a past half-century, with the yield doubled in most parts of the world and even tripled in certain regions, which has contributed\\u000a greatly to food security globally. However, rice yield recently reached a ceiling due to increasingly severe occurrences of

Hao Chen; Yongjun Lin; Qifa Zhang

31

[Controlling effects of multiple species coexistence on rice diseases, pests and weeds in paddy field ecosystem].  

PubMed

Establishing a species-diversified cropping system to control crop diseases, insect pests and weeds is an important approach to sustainable agricultural development. This paper reviewed the researches on paddy field species-diversified cropping systems at home and abroad, and discussed the controlling effects and mechanisms of multiple species coexistence on rice diseases, pests and weeds control. The multiple species coexistence models such as rice-fish, rice-duck, rice-azolla-fish and rice-azolla-duck had effective controlling effects on Thanatephorus cucumeris (Frank) Donk, Nilaparata lugens Stal, Chaphalocrocis medinalis Gueneeand, and weeds. Other models like intercropping rice with Zizania caduciflora L. and with other wetland crops also had effective effects in controlling the occurrence and spread of Pyricularia grisea. It was suggested that further studies should be strengthened from the viewpoints of crop culture, molecular biology, and chemical ecolo- PMID:17650871

Wang, Han; Tang, Jian-jun; Xie, Jian; Chen, Xin

2007-05-01

32

Modeling greenhouse gas emissions from rice-based production systems: Sensitivity and upscaling  

Microsoft Academic Search

A biogeochemical model, Denitrification-Decomposition (DNDC), was modified to enhance its capacity of predicting greenhouse gas (GHG) emissions from paddy rice ecosystems. The major modifications focused on simulations of anaerobic biogeochemistry and rice growth as well as parameterization of paddy rice management. The new model was tested for its sensitivities to management alternatives and variations in natural conditions including weather and

Changsheng Li; Arvin Mosier; Reiner Wassmann; Zucong Cai; Xunhua Zheng; Yao Huang; Haruo Tsuruta; Jariya Boonjawat; Rhoda Lantin

2004-01-01

33

The LGU Extension Services in a Major Rice-Growing Area: The Case of Hagonoy, Davao del Sur  

Microsoft Academic Search

The province of Davao del Sur is considered one of the major rice-producing provinces of Region XI. It has been regarded as Mindanao’s top rice-yielding province because of its municipality’s (Hagonoy) high yield performance. The study shows that farmers have multiple sources of information within a given farming system. In addition to formal institutions like the national and regional agencies,

Rosa Fe D. Hondrade

2007-01-01

34

Comparative impacts of two major hurricane seasons on the Neuse River and western Pamlico Sound ecosystems  

Microsoft Academic Search

Ecosystem-level impacts of two hurricane seasons were compared several years after the storms in the largest lagoonal estuary in the U.S., the Albemarle-Pamlico Estuarine System. A segmented linear regression flow model was developed to compare mass-water transport and nutrient loadings to a major artery, the Neuse River Estuary (NRE), and to estimate mean annual versus storm-related volume delivery to the

Joann Burkholder; David Eggleston; Howard Glasgow; Cavell Brownie; Robert Reed; Gerald Janowitz; Martin Posey; Greg Melia; Carol Kinder; Reide Corbett; David Toms; Troy Alphin; Nora Deamer; Jeffrey Springer

2004-01-01

35

Transgenic rice expressing Allium sativum leaf agglutinin (ASAL) exhibits high-level resistance against major sap-sucking pests  

PubMed Central

Background Rice (Oryza sativa) productivity is adversely impacted by numerous biotic and abiotic factors. An approximate 52% of the global production of rice is lost annually owing to the damage caused by biotic factors, of which ~21% is attributed to the attack of insect pests. In this paper we report the isolation, cloning and characterization of Allium sativum leaf agglutinin (asal) gene, and its expression in elite indica rice cultivars using Agrobacterium-mediated genetic transformation method. The stable transgenic lines, expressing ASAL, showed explicit resistance against major sap-sucking pests. Results Allium sativum leaf lectin gene (asal), coding for mannose binding homodimeric protein (ASAL) from garlic plants, has been isolated and introduced into elite indica rice cultivars susceptible to sap-sucking insects, viz., brown planthopper (BPH), green leafhopper (GLH) and whitebacked planthopper (WBPH). Embryogenic calli of rice were co-cultivated with Agrobacterium harbouring pSB111 super-binary vector comprising garlic lectin gene asal along with the herbicide resistance gene bar, both under the control of CaMV35S promoter. PCR and Southern blot analyses confirmed stable integration of transgenes into the genomes of rice plants. Northern and western blot analyses revealed expression of ASAL in different transgenic rice lines. In primary transformants, the level of ASAL protein, as estimated by enzyme-linked immunosorbent assay, varied between 0.74% and 1.45% of the total soluble proteins. In planta insect bioassays on transgenic rice lines revealed potent entomotoxic effects of ASAL on BPH, GLH and WBPH insects, as evidenced by significant decreases in the survival, development and fecundity of the insects. Conclusion In planta insect bioassays were carried out on asal transgenic rice lines employing standard screening techniques followed in conventional breeding for selection of insect resistant plants. The ASAL expressing rice plants, bestowed with high entomotoxic effects, imparted appreciable resistance against three major sap-sucking insects. Our results amply demonstrate that transgenic indica rice harbouring asal exhibit surpassing resistance against BPH, GLH and WBPH insects. The prototypic asal transgenic rice lines appear promising for direct commercial cultivation besides serving as a potential genetic resource in recombination breeding.

Yarasi, Bharathi; Sadumpati, Vijayakumar; Immanni, China Pasalu; Vudem, Dasavantha Reddy; Khareedu, Venkateswara Rao

2008-01-01

36

Assessment of toxicity risk of insecticides used in rice ecosystem on Trichogramma japonicum, an egg parasitoid of rice lepidopterans.  

PubMed

Both chemical and biological methods are essential for control of insects, for example, lepidopterans, on rice. Thus, it is important to know the effect of chemicals on the biological control agents. In this study, we assessed the toxicity of commonly used insecticides on a biological control agent, Trichogramma japonicum Ahmead (an egg parasitoid of rice lepidopterans) by using a dry film residue method. Results showed that thirty insecticides from seven chemical classes exhibited various degree of toxicity to this parasitoid. Among the seven classes of chemicals tested, organophosphates (chlorpyrifos, fenitrothion, phoxim, profenofos, and triazophos) and carbamates (carbaryl, carbsulfan, isoprocarb, metolcarb, and promecarb) exhibited the highest intrinsic toxicity to T. japponicum, with an LC50 of 0.035 (0.029-0.044) to 0.49 (0.34-0.87) mg active ingredient (a.i.) L(-1), followed by antibiotics (abamectin, emamectin benzoate, and ivermectin), phenylpyrazoles (butane-fipronil, ethiprole, and fipronil), pyrethroids (cyhalthrin, cypermethrin, fenpropathrin, and lambda-cyhaothrin), and neonicotinoids (acetamiprid, imidacloprid, imidaclothiz, nitenpyram, thiacloprid, and thiamethoxam). Moreover, the insect growth regulator insecticides (chlorfluazuron, fufenozide, hexaflumuron and tebufenozide) exhibited the lowest toxicity to the wasps with an LC50 of 3,383 (2406-5499) to 30206 (23107-41008) mg ai. L(-1). Risk quotient analysis showed that phenylpyrazoles, pyrethroids, insect growth regulators, neonicotinoids (with the exception of thiamethoxam), and antibiotics (with the exception of abamectin) are classified as safe agents to the parasitoid, while organophosphates and carbamates are classified as slightly, moderately, or highly toxic agents to the parasitoid. The data presented in this paper provided useful information on the selection of compatible insecticides with T. japonicum. PMID:22420260

Zhao, Xueping; Wu, Changxing; Wang, Yanhua; Cang, Tao; Chen, Liping; Yu, Ruixian; Wang, Qiang

2012-02-01

37

Dissipation of fuphenthiourea residues in rice and field ecosystem after seed soaking application.  

PubMed

An analytical method with SPE or matrix solid-phase dispersion clean-up procedure on PSA followed by HPLC-DAD was established for determination of fuphenthiourea residues in rice, water and soil. At three concentration levels (0.05, 0.5 and 5 mg kg(-1)), recoveries were in the range of 61.2-82.7%, with a RSD less than 13%. The LOQ of this method was 0.005, 0.02 and 0.01 mg kg(-1) for the water, soil and rice samples, respectively. Fuphenthiourea was applied in supervised ?eld trials at GAP conditions during rice seeding. It was found that under field conditions, the dissipation half-lives of fuphenthiourea were 0.8 d in the water and 24.8 d in the soil. At harvest, no detectable residues (

Jiang, Yaping; Bao, Yongxiao; Pan, Canping

2011-01-06

38

The root microbiome influences scales from molecules to ecosystems: The unseen majority1.  

PubMed

Plants are teeming with microbial organisms including those that colonize internal tissues as well as those that adhere to external surfaces. In the rhizosphere, the plant-associated microbiome is intricately involved in plant health and serves as a reservoir of additional genes that plants can access when needed. Microbiome regulation of plant trait expression affects plant performance, which in turn influences various ecosystem functions, such as primary productivity and soil health. Understanding these plant- and microbe-driven interactions requires a study of the nature and effects of the plant microbiome. Conceptualizing the microbiome requires a synthesis of microbial ecology, physiology, and bioinformatics, integrated with insight into host biology and ecology. Microbiome structure and function analyses are recognized as essential components to understand the genetic and functional capacity of the host (previously assigned solely to the host) and include vital aspects of metabolism and physiology. Here, as a special section, we present a set of papers that address the complex interactions between plants and root microbiomes in the rhizosphere. This unseen majority spans scales; with its microorganisms numerically dominant in terrestrial ecosystems, the root microbiome is also involved in plant genetics through integral roles in plant trait expression that can effect community composition and ecosystem functions, such as soil health. PMID:24008514

Rout, Marnie E; Southworth, Darlene

2013-09-05

39

Diversity of azospirillum strains isolated from rice plants grown in saline and nonsaline sites of coastal agricultural ecosystem.  

PubMed

The diversity of indigenous Azospirillum spp. associated with rice cultivated along the coastline of Tamil Nadu was analyzed. Twelve sites with varying soil characteristics such as salinity, texture, and the host variety were chosen. Of the 402 strains isolated using NFB media, 302 were confirmed to be Azospirillum spp. and subjected to DNA polymorphism analysis using PCR-RFLP of 16S rDNA. They were also screened for their salt tolerance and microaerobic N2-fixing-dependent growth. On species identification, all the strains were found to be A. brasilense, A. lipoferum, or unidentified. On comparing the influence of the previously noted variability on the indigenous population, soil salinity was found to play a dominant role. This was revealed by PCR-RFLP studies and salt tolerance studies. A high association between soil salinity and the distribution of Azospirillum genotypes reveals that soil salinity should be taken into consideration while developing biofertilizers specifically for the coastal agricultural ecosystem. PMID:12209252

Saleena, L M; Rangarajan, S; Nair, S

2002-09-06

40

An economical approach for d-lactic acid production utilizing unpolished rice from aging paddy as major nutrient source.  

PubMed

In order to reduce the raw material cost of d-lactic acid fermentation, the unpolished rice from aging paddy was used as major nutrient source in this study. The unpolished rice saccharificate, wheat bran powder and yeast extract were employed as carbon source, nitrogen source and growth factors, respectively. Response surface methodology (RSM) was applied to optimize the dosages of medium compositions. As a result, when the fermentation was carried out under the optimal conditions for wheat bran powder (29.10g/l) and yeast extract (2.50g/l), the d-lactic acid yield reached 731.50g/kg unpolished rice with a volumetric production rate of 1.50g/(lh). In comparison with fresh corn and polished rice, the d-lactic acid yield increased by 5.79% and 8.71%, and the raw material cost decreased by 65% and 52%, respectively, when the unpolished rice was used as a major nutrient source. These results might provide a reference for the industrial production of d-lactic acid. PMID:19027289

Lu, Zhengdong; Lu, Mingbo; He, Feng; Yu, Longjiang

2008-11-21

41

40 CFR Table 2c to Subpart Zzzz of... - Requirements for Existing Compression Ignition Stationary Rice Located at Major Sources of HAP...  

Code of Federal Regulations, 2010 CFR

...Rice Located at Major Sources of HAP Emissions 2c...HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED...Stationary Reciprocating Internal Combustion Engines ...Rice Located at Major Sources of HAP Emissions As...appropriate and safe loading of the engine,...

2010-07-01

42

Genetic component and combining ability analyses in relation to heterosis for yield and associated traits using three diverse rice-growing ecosystems  

Microsoft Academic Search

Genetically designed analyses for gene governance components, combining abilities, heterosis, inbreeding depression and genetic gains were made utilizing a seven-parent half-diallel mating design having several locally adapted, traditional varieties or land races from three diverse rice ecosystems. Both additive and non-additive genes were found to control the expression of yield and its associated traits. The ratio of ??g2\\/??s2 exhibited greater

O. P. Verma; H. K. Srivastava

2004-01-01

43

Impacts of transgenic cry1Ab rice on non-target planthoppers and their main predator Cyrtorhinus lividipennis (Hemiptera: Miridae)—A case study of the compatibility of Bt rice with biological control  

Microsoft Academic Search

Transgenic rice containing insecticidal protein(s) from Bt (Bacillus thuringiensis) effectively control lepidopteran pests under laboratory and field conditions. However, Bt rice has not been widely commercialized. A major concern regarding the deployment of Bt rice is its potential impact on non-target arthropods, including herbivorous insect pests and biological control agents (predators and parasitoids) in the rice ecosystem. A 2-year field

Mao Chen; Zhi-cheng Liu; Gong-yin Ye; Zhi-cheng Shen; Cui Hu; Yu-fa Peng; Illimar Altosaar; Anthony M. Shelton

2007-01-01

44

Health Benefits and Clinical Impact of Major Nutrient, Red Yeast Rice: A Review  

Microsoft Academic Search

Chinese red yeast rice (RYR), a natural food obtained after fermenting rice with Monascus purpureus. RYR contains unsaturated fatty acids, sterols, B-complex vitamins and monacolins with antioxidant properties. Scientific\\u000a evidences showed that fermented RYR proved to be effective for the management of cholesterol, diabetes, cardiovascular disease\\u000a (CVD) and also for the prevention of cancer. This review article describe about the

M. Kalaivani; R. Sabitha; V. Kalaiselvan; A. Rajasekaran

2010-01-01

45

Interacting factors driving a major loss of large trees with cavities in a forest ecosystem.  

PubMed

Large trees with cavities provide critical ecological functions in forests worldwide, including vital nesting and denning resources for many species. However, many ecosystems are experiencing increasingly rapid loss of large trees or a failure to recruit new large trees or both. We quantify this problem in a globally iconic ecosystem in southeastern Australia--forests dominated by the world's tallest angiosperms, Mountain Ash (Eucalyptus regnans). Tree, stand and landscape-level factors influencing the death and collapse of large living cavity trees and the decay and collapse of dead trees with cavities are documented using a suite of long-term datasets gathered between 1983 and 2011. The historical rate of tree mortality on unburned sites between 1997 and 2011 was >14% with a mortality spike in the driest period (2006-2009). Following a major wildfire in 2009, 79% of large living trees with cavities died and 57-100% of large dead trees were destroyed on burned sites. Repeated measurements between 1997 and 2011 revealed no recruitment of any new large trees with cavities on any of our unburned or burned sites. Transition probability matrices of large trees with cavities through increasingly decayed condition states projects a severe shortage of large trees with cavities by 2039 that will continue until at least 2067. This large cavity tree crisis in Mountain Ash forests is a product of: (1) the prolonged time required (>120 years) for initiation of cavities; and (2) repeated past wildfires and widespread logging operations. These latter factors have resulted in all landscapes being dominated by stands ?72 years and just 1.16% of forest being unburned and unlogged. We discuss how the features that make Mountain Ash forests vulnerable to a decline in large tree abundance are shared with many forest types worldwide. PMID:23071486

Lindenmayer, David B; Blanchard, Wade; McBurney, Lachlan; Blair, David; Banks, Sam; Likens, Gene E; Franklin, Jerry F; Laurance, William F; Stein, John A R; Gibbons, Philip

2012-10-05

46

Comparative impacts of two major hurricane seasons on the Neuse River and western Pamlico Sound ecosystems  

PubMed Central

Ecosystem-level impacts of two hurricane seasons were compared several years after the storms in the largest lagoonal estuary in the U.S., the Albemarle–Pamlico Estuarine System. A segmented linear regression flow model was developed to compare mass-water transport and nutrient loadings to a major artery, the Neuse River Estuary (NRE), and to estimate mean annual versus storm-related volume delivery to the NRE and Pamlico Sound. Significantly less water volume was delivered by Hurricane Fran (1996), but massive fish kills occurred in association with severe dissolved oxygen deficits and high contaminant loadings (total nitrogen, total phosphorus, suspended solids, and fecal bacteria). The high water volume of the second hurricane season (Hurricanes Dennis, Floyd, and Irene in 1999) delivered generally comparable but more dilute contaminant loads, and no major fish kills were reported. There were no discernable long-term adverse impacts on water quality. Populations of undesirable organisms, such as toxic dinoflagellates, were displaced down-estuary to habitats less conducive for growth. The response of fisheries was species-dependent: there was no apparent impact of the hurricanes on commercial landings of bivalve molluscs or shrimp. In contrast, interacting effects of hurricane floodwaters in 1999 and intensive fishing pressure led to striking reductions in blue crabs. Overall, the data support the premise that, in shallow estuaries frequently disturbed by hurricanes, there can be relatively rapid recovery in water quality and biota, and benefit from the scouring activity of these storms.

Burkholder, JoAnn; Eggleston, David; Glasgow, Howard; Brownie, Cavell; Reed, Robert; Janowitz, Gerald; Posey, Martin; Melia, Greg; Kinder, Carol; Corbett, Reide; Toms, David; Alphin, Troy; Deamer, Nora; Springer, Jeffrey

2004-01-01

47

Comparative impacts of two major hurricane seasons on the Neuse River and western Pamlico Sound ecosystems.  

PubMed

Ecosystem-level impacts of two hurricane seasons were compared several years after the storms in the largest lagoonal estuary in the U.S., the Albemarle-Pamlico Estuarine System. A segmented linear regression flow model was developed to compare mass-water transport and nutrient loadings to a major artery, the Neuse River Estuary (NRE), and to estimate mean annual versus storm-related volume delivery to the NRE and Pamlico Sound. Significantly less water volume was delivered by Hurricane Fran (1996), but massive fish kills occurred in association with severe dissolved oxygen deficits and high contaminant loadings (total nitrogen, total phosphorus, suspended solids, and fecal bacteria). The high water volume of the second hurricane season (Hurricanes Dennis, Floyd, and Irene in 1999) delivered generally comparable but more dilute contaminant loads, and no major fish kills were reported. There were no discernable long-term adverse impacts on water quality. Populations of undesirable organisms, such as toxic dinoflagellates, were displaced down-estuary to habitats less conducive for growth. The response of fisheries was species-dependent: there was no apparent impact of the hurricanes on commercial landings of bivalve molluscs or shrimp. In contrast, interacting effects of hurricane floodwaters in 1999 and intensive fishing pressure led to striking reductions in blue crabs. Overall, the data support the premise that, in shallow estuaries frequently disturbed by hurricanes, there can be relatively rapid recovery in water quality and biota, and benefit from the scouring activity of these storms. PMID:15199179

Burkholder, JoAnn; Eggleston, David; Glasgow, Howard; Brownie, Cavell; Reed, Robert; Janowitz, Gerald; Posey, Martin; Melia, Greg; Kinder, Carol; Corbett, Reide; Toms, David; Alphin, Troy; Deamer, Nora; Springer, Jeffrey

2004-06-15

48

Evolutionary responses by native species to major anthropogenic changes to their ecosystems: Pacific salmon in the Columbia River hydropower system  

Microsoft Academic Search

The human footprint is now large in all the Earth's ecosystems, and construction of large dams in major river basins is among the anthropogenic changes that have had the most profound ecological consequences, particularly for migratory fishes. In the Columbia River basin of the western USA, considerable effort has been directed toward evaluating demo- graphic effects of dams, yet little

ROBIN S. WAPLES; RICHARD W. ZABEL; MARK D. SCHEUERELL; BETH L. SANDERSON

2007-01-01

49

Major cis-regulatory elements for rice bidirectional promoter activity reside in the 5'-untranslated regions.  

PubMed

Bidirectional promoters are defined as those that regulate adjacent genes organized in a divergent fashion (head to head orientation) and separated by <1 kb. In order to dissect bidirectional promoter activity in a model plant, deletion analysis was performed for seven rice promoters using promoter-reporter gene constructs, which identified three promoters to be bidirectional. Regulatory elements located in or close to the 5'-untranslated regions (UTR) of one of the genes (divergent gene pair) were found to be responsible for their bidirectional activity. DNA footprinting analysis identified unique protein binding sites in these promoters. Deletion/alteration of these motifs resulted in significant loss of expression of the reporter genes on either side of the promoter. Changes in the motifs at both the positions resulted in a remarkable decrease in bidirectional activity of the reporter genes flanking the promoter. Based on our results, we propose a novel mechanism for the bidirectionality of rice bidirectional promoters. PMID:23756196

Dhadi, Surendar Reddy; Deshpande, Aparna; Driscoll, Kyle; Ramakrishna, Wusirika

2013-06-10

50

Major Phenolic Compounds, Antioxidant Capacity and Antidiabetic Potential of Rice Bean (Vigna umbellata L.) in China.  

PubMed

Interest in edible beans as nutraceuticals is increasing. In the present study, the individual phenolic acids, the total phenolic content (TPC), the total flavonoid content (TFC), and the antioxidant and antidiabetic potential of 13 varieties of rice beans from China were investigated. Eight phenolic compounds (catechin, epicatechin, p-coumaric acid, ferulic acid, vitexin, isovitexin, sinapic acid, quercetin) were analyzed on an ultra-performance liquid chromatography (UPLC) mass spectrometry (MS) system. The rice bean varieties had significant differences in total phenolic compounds (ranging from 123.09 ± 10.35 to 843.75 ± 30.15 ?g/g), in TPC (ranging from 3.27 ± 0.04 to 6.43 ± 0.25 mg gallic acid equivalents (GAE)/g), in TFC (ranging from 55.95 ± 11.16 to 320.39 ± 31.77 mg catechin (CE)/g), in antioxidant activity (ranging from 39.87 ± 1.37 to 46.40 ± 2.18 ?M·TE/g), in ?-glucosidase inhibition activity (ranging from 44.32 ± 2.12 to 68.71 ± 2.19) and in advanced glycation end products formation inhibition activity (ranging from 34.11 ± 0.59 to 75.75 ± 0.33). This study is the first report on phytochemistry and biological activities in rice beans. PMID:22489119

Yao, Yang; Cheng, Xu-Zhen; Wang, Li-Xia; Wang, Su-Hua; Ren, Guixing

2012-02-29

51

Major Phenolic Compounds, Antioxidant Capacity and Antidiabetic Potential of Rice Bean (Vigna umbellata L.) in China  

PubMed Central

Interest in edible beans as nutraceuticals is increasing. In the present study, the individual phenolic acids, the total phenolic content (TPC), the total flavonoid content (TFC), and the antioxidant and antidiabetic potential of 13 varieties of rice beans from China were investigated. Eight phenolic compounds (catechin, epicatechin, p-coumaric acid, ferulic acid, vitexin, isovitexin, sinapic acid, quercetin) were analyzed on an ultra-performance liquid chromatography (UPLC) mass spectrometry (MS) system. The rice bean varieties had significant differences in total phenolic compounds (ranging from 123.09 ± 10.35 to 843.75 ± 30.15 ?g/g), in TPC (ranging from 3.27 ± 0.04 to 6.43 ± 0.25 mg gallic acid equivalents (GAE)/g), in TFC (ranging from 55.95 ± 11.16 to 320.39 ± 31.77 mg catechin (CE)/g), in antioxidant activity (ranging from 39.87 ± 1.37 to 46.40 ± 2.18 ?M·TE/g), in ?-glucosidase inhibition activity (ranging from 44.32 ± 2.12 to 68.71 ± 2.19) and in advanced glycation end products formation inhibition activity (ranging from 34.11 ± 0.59 to 75.75 ± 0.33). This study is the first report on phytochemistry and biological activities in rice beans.

Yao, Yang; Cheng, Xu-Zhen; Wang, Li-Xia; Wang, Su-Hua; Ren, Guixing

2012-01-01

52

Species and ecosystem level bioindicators of airborne pollution: An analysis of two major studies  

Microsoft Academic Search

Bioindication of air pollution effects has received considerable attention in recent years. It has been almost entirely focused on individual species and relatively little notice has been given to ecosystem level process and function monitors. Longterm research projects in the Niepolomice Forest in southern Poland and the Colstrip area in southeast Montana, U.S.A., were analyzed for both organismic and system

W. Grodzi?ski; T. P. Yorks

1981-01-01

53

MucoRice-cholera toxin B-subunit, a rice-based oral cholera vaccine, down-regulates the expression of ?-amylase/trypsin inhibitor-like protein family as major rice allergens.  

PubMed

To develop a cold chain- and needle/syringe-free rice-based cholera vaccine (MucoRice-CTB) for human use, we previously advanced the MucoRice system by introducing antisense genes specific for endogenous rice storage proteins and produced a molecularly uniform, human-applicable, high-yield MucoRice-CTB devoid of plant-associated sugar. To maintain the cold chain-free property of this vaccine for clinical application, we wanted to use a polished rice powder preparation of MucoRice-CTB without further purification but wondered whether this might cause an unexpected increase in rice allergen protein expression levels in MucoRice-CTB and prompt safety concerns. Therefore, we used two-dimensional fluorescence difference gel electrophoresis and shotgun MS/MS proteomics to compare rice allergen protein expression levels in MucoRice-CTB and wild-type (WT) rice. Both proteomics analyses showed that the only notable change in the expression levels of rice allergen protein in MucoRice-CTB, compared with those in WT rice, was a decrease in the expression levels of ?-amylase/trypsin inhibitor-like protein family such as the seed allergen protein RAG2. Real-time PCR analysis showed mRNA of RAG2 reduced in MucoRice-CTB seed. These results demonstrate that no known rice allergens appear to be up-reregulated by genetic modification of MucoRice-CTB, suggesting that MucoRice-CTB has potential as a safe oral cholera vaccine for clinical application. PMID:23763241

Kurokawa, Shiho; Nakamura, Rika; Mejima, Mio; Kozuka-Hata, Hiroko; Kuroda, Masaharu; Takeyama, Natsumi; Oyama, Masaaki; Satoh, Shigeru; Kiyono, Hiroshi; Masumura, Takehiro; Teshima, Reiko; Yuki, Yoshikazu

2013-06-25

54

Major Changes in the Ecology of the Wadden Sea: Human Impacts, Ecosystem Engineering and Sediment Dynamics  

Microsoft Academic Search

Shallow soft-sediment systems are mostly dominated by species that, by strongly affecting sediment dynamics, modify their\\u000a local environment. Such ecosystem engineering species can have either sediment-stabilizing or sediment-destabilizing effects\\u000a on tidal flats. They interplay with abiotic forcing conditions (wind, tide, nutrient inputs) in driving the community structure\\u000a and generating spatial heterogeneity, determining the composition of different communities of associated species,

Britas Klemens Eriksson; Tjisse van der Heide; Johan van de Koppel; Theunis Piersma; Henk W. van der Veer; Han Olff

2010-01-01

55

40 CFR Table 2c to Subpart Zzzz of... - Requirements for Existing Compression Ignition Stationary RICE Located at a Major Source of HAP...  

Code of Federal Regulations, 2013 CFR

...stationary RICE located at a major source of HAP emissions and existing...500 HP located at a major source of HAP emissions: For each...percent or more of the gross heat input on an annual basis ...or local law has abated. Sources must report any failure...

2013-07-01

56

A survey of rice insect pests in Nigeria  

Microsoft Academic Search

A survey of rice insect pests conducted during 1983–87 in Nigeria revealed 70 species of pests, 14 parasitoids and two predators. Both incidence and severity of pests varied considerably across different climatic zones and rice agro?ecosystems. Thirteen Insects were classified as major pests. They are: stalk?eyed fly. Diopsis longicornis Macquart; lepidopterous stem borers. Mallarpha separatella Rag., Chllo zacconius Blesz, Sesamia

M. S. Alam

1992-01-01

57

Diversity and population dynamics of pests and predators in irrigated rice fields with treated and untreated pesticide.  

PubMed

The monitoring of rice pests and their predators in pesticide untreated and treated rice fields was conducted at the southern of Thailand. Twenty-two species in 15 families and 6 orders of rice pests were sampled from untreated rice field. For treated rice field, 22 species in 14 families and 5 orders of rice pest were collected. Regardless of treatment type, dominant species and individual number of rice pest varied to physiological stage of rice. Lepidopteran pests had highest infestation during the vegetative stage of rice growth, while hemipteran pests composed of hopper species (Hemipetra: Auchenorrhyncha) and heteropteran species (Hemiptera: Heteroptera) were dominant groups during the reproductive stage and grain formation and ripening stage of rice growth. In contrast, dominant species of predator did not change throughout rice growing season. There were 35 species in 25 families and seven orders and 40 species in 29 families and seven orders of predators collected from untreated and treated rice field, respectively. Major predators of both rice fields were Micraspis discolor (Fabricius) (Coleoptera: Coccinellidae), Tetragnatha sp. (Araneae: Tetragnathidae) and Agriocnemis pygmaea Rambur (Odonata: Agrionidae). The population dynamic of predators were not related with rice pest population in both treatments. However, the fluctuation of population pattern of rice pests in the untreated treatment were more distinctly synchronized with their predators than that of the treated treatment. There were no significant differences in the total number of rice pest and predator between two treatments at vegetative and reproductive stages of rice growth. Untreated rice field had a higher population number of predator and a lower population number of rice pest than that of treated rice field during grain formation and ripening stages. These results indicated the ago-ecosystem balance in rice fields could be produced through minimal pesticide application, in order to allow the natural balance between pests and their predators to be restored and maintained. PMID:23885426

Rattanapun, W

2012-01-01

58

In Inland China, Rice, Rather than Fish, Is the Major Pathway for Methylmercury Exposure  

PubMed Central

Background Fish consumption is considered the primary pathway of methylmercury (MeHg) exposure for most people in the world. However, in the inland regions of China, most of the residents eat little fish, but they live in areas where a significant amount of mercury (Hg) is present in the environment. Objectives We assessed concentrations of total Hg and MeHg in samples of water, air, agricultural products, and other exposure media to determine the main exposure pathway of Hg in populations in inland China. Methods We selected Guizhou Province for our study because it is highly contaminated with Hg and therefore is representative of other Hg-contaminated areas in China. We selected four study locations in Guizhou Province: three that represent typical environments with severe Hg pollution [due to Hg mining and smelting (Wanshan), traditional zinc smelting (recently closed; Weining), and heavy coal-based industry (Qingzhen)], and a village in a remote nature reserve (Leigong). Results The probable daily intake (PDI) of MeHg for an adult population based on 60 kg body weight (bw) was considerably higher in Wanshan than in the other three locations. With an average PDI of 0.096 ?g/kg bw/day (range, 0.015–0.45 ?g/kg bw/day), approximately 34% of the inhabitants in Wanshan exceeded the reference dose of 0.1 ?g/kg bw/day established by the U.S. Environmental Protection Agency. The PDI of MeHg for residents in the three other locations were all well below 0.1 ?g/kg bw/day (averages from 0.017 to 0.023 ?g/kg bw/day, with a maximum of 0.095 ?g/kg bw/day). In all four areas, rice consumption accounted for 94–96% of the PDI of MeHg. Conclusion We found that rice consumption is by far the most important MeHg exposure route; however, most of the residents (except those in Hg-mining areas) have low PDIs of MeHg.

Zhang, Hua; Feng, Xinbin; Larssen, Thorj?rn; Qiu, Guangle; Vogt, Rolf D.

2010-01-01

59

Root-to-shoot Cd translocation via the xylem is the major process determining shoot and grain cadmium accumulation in rice  

PubMed Central

Physiological properties involved in divergent cadmium (Cd) accumulation among rice genotypes were characterized using the indica cultivar ‘Habataki’ (high Cd in grains) and the japonica cultivar ‘Sasanishiki’ (low Cd in grains). Time-dependence and concentration-dependence of symplastic Cd absorption in roots were revealed not to be responsible for the different Cd accumulation between the two cultivars because root Cd uptake was not greater in the Cd-accumulating cultivar ‘Habataki’ compared with ‘Sasanishiki’. On the other hand, rapid and greater root-to-shoot Cd translocation was observed in ‘Habataki’, which could be mediated by higher abilities in xylem loading of Cd and transpiration rate as a driving force. To verify whether different abilities in xylem-mediated shoot-to-root translocation generally account for the genotypic variation in shoot Cd accumulation in rice, the world rice core collection, consisting of 69 accessions which covers the genetic diversity of almost 32 000 accessions of cultivated rice, was used. The results showed strong correlation between Cd levels in xylem sap and shoots and grains among the 69 rice accessions. Overall, the results presented in this study revealed that the root-to-shoot Cd translocation via the xylem is the major and common physiological process determining the Cd accumulation level in shoots and grains of rice plants.

Uraguchi, Shimpei; Mori, Shinsuke; Kuramata, Masato; Kawasaki, Akira; Arao, Tomohito; Ishikawa, Satoru

2009-01-01

60

Gene expression analysis of rice seedling under potassium deprivation reveals major changes in metabolism and signaling components.  

PubMed

Plant nutrition is one of the important areas for improving the yield and quality in crops as well as non-crop plants. Potassium is an essential plant nutrient and is required in abundance for their proper growth and development. Potassium deficiency directly affects the plant growth and hence crop yield and production. Recently, potassium-dependent transcriptomic analysis has been performed in the model plant Arabidopsis, however in cereals and crop plants; such a transcriptome analysis has not been undertaken till date. In rice, the molecular mechanism for the regulation of potassium starvation responses has not been investigated in detail. Here, we present a combined physiological and whole genome transcriptomic study of rice seedlings exposed to a brief period of potassium deficiency then replenished with potassium. Our results reveal that the expressions of a diverse set of genes annotated with many distinct functions were altered under potassium deprivation. Our findings highlight altered expression patterns of potassium-responsive genes majorly involved in metabolic processes, stress responses, signaling pathways, transcriptional regulation, and transport of multiple molecules including K(+). Interestingly, several genes responsive to low-potassium conditions show a reversal in expression upon resupply of potassium. The results of this study indicate that potassium deprivation leads to activation of multiple genes and gene networks, which may be acting in concert to sense the external potassium and mediate uptake, distribution and ultimately adaptation to low potassium conditions. The interplay of both upregulated and downregulated genes globally in response to potassium deprivation determines how plants cope with the stress of nutrient deficiency at different physiological as well as developmental stages of plants. PMID:23922980

Shankar, Alka; Singh, Amarjeet; Kanwar, Poonam; Srivastava, Ashish Kumar; Pandey, Amita; Suprasanna, Penna; Kapoor, Sanjay; Pandey, Girdhar K

2013-07-29

61

Gene Expression Analysis of Rice Seedling under Potassium Deprivation Reveals Major Changes in Metabolism and Signaling Components  

PubMed Central

Plant nutrition is one of the important areas for improving the yield and quality in crops as well as non-crop plants. Potassium is an essential plant nutrient and is required in abundance for their proper growth and development. Potassium deficiency directly affects the plant growth and hence crop yield and production. Recently, potassium-dependent transcriptomic analysis has been performed in the model plant Arabidopsis, however in cereals and crop plants; such a transcriptome analysis has not been undertaken till date. In rice, the molecular mechanism for the regulation of potassium starvation responses has not been investigated in detail. Here, we present a combined physiological and whole genome transcriptomic study of rice seedlings exposed to a brief period of potassium deficiency then replenished with potassium. Our results reveal that the expressions of a diverse set of genes annotated with many distinct functions were altered under potassium deprivation. Our findings highlight altered expression patterns of potassium-responsive genes majorly involved in metabolic processes, stress responses, signaling pathways, transcriptional regulation, and transport of multiple molecules including K+. Interestingly, several genes responsive to low-potassium conditions show a reversal in expression upon resupply of potassium. The results of this study indicate that potassium deprivation leads to activation of multiple genes and gene networks, which may be acting in concert to sense the external potassium and mediate uptake, distribution and ultimately adaptation to low potassium conditions. The interplay of both upregulated and downregulated genes globally in response to potassium deprivation determines how plants cope with the stress of nutrient deficiency at different physiological as well as developmental stages of plants.

Shankar, Alka; Singh, Amarjeet; Kanwar, Poonam; Srivastava, Ashish Kumar; Pandey, Amita; Suprasanna, Penna; Kapoor, Sanjay; Pandey, Girdhar K.

2013-01-01

62

Development of sustainable groundwater extraction practices for a major superficial aquifer supporting a groundwater dependent ecosystem  

NASA Astrophysics Data System (ADS)

Throughout Australia many groundwater dependent ecosystems have been adversely affected by unsympathetic water abstraction practices. In Western Australia, the largest single supply of drinking water for the city of Perth is a superficial aquifer known as the Gnangara Groundwater Mound, located over an area of approximately 2200 km2 within and to the north of the city on the coastal plain. The groundwater resource supplies 60% of Perth’s pubic drinking water supply and 85% of total water demand for all users. Much of the mound is overlain by phreatophytic Banksia woodland that is susceptible to drought stress and death if the root system is separated from the unconfined aquifer for prolonged periods over the hot, dry Mediterranean summer. Drought stress has been exacerbated by diminished rainfall due to a changing climate regime. The aim of this research is to develop guidelines for sustainable groundwater abstraction (timing and volume) that will maintain the long term integrity of the ecosystem and recover up to 5GL/yr from existing borefields. We seek to investigate whether a change in abstraction regime, from ‘peak demand’ summer pumping to winter pumping allows groundwater levels to recover sufficiently prior to summer, thereby maintaining a healthy vegetation system. Hydrological and plant water status parameters were monitored over two winters at research sites with an initial depth to groundwater of less than 5m. During winter and spring, groundwater abstraction at a reduced capacity resulted in a 0.75m drawdown. Operation of the bores did not adversely impact the water status of phreatophytic Banksia at the study sites relative to control sites. Analysis of plant water source partitioning indicated that plants exposed to the winter drawdown were sustained by unsaturated zone soil moisture storage replenished by winter rainfall. When pumping ceased, the water table rose rapidly and plants utilised more groundwater during late spring and summer as the soil water store became depleted. A simple water balance model combined with phreatophyte vulnerability assessment was employed to identify allowable magnitude and rate of drawdown, and duration of bore operation.

Smettem, K. R.; Froend, R.; Davies, M.; Stock, B.; Martin, M.; Robertson, C.; Eamus, D.

2010-12-01

63

Homology modeling of major intrinsic proteins in rice, maize and Arabidopsis: comparative analysis of transmembrane helix association and aromatic\\/arginine selectivity filters  

Microsoft Academic Search

BACKGROUND: The major intrinsic proteins (MIPs) facilitate the transport of water and neutral solutes across the lipid bilayers. Plant MIPs are believed to be important in cell division and expansion and in water transport properties in response to environmental conditions. More than 30 MIP sequences have been identified in Arabidopsis thaliana, maize and rice. Plasma membrane intrinsic proteins (PIPs), tonoplast

Anjali Bansal; Ramasubbu Sankararamakrishnan

2007-01-01

64

From the Cover: A triallelic system of S5 is a major regulator of the reproductive barrier and compatibility of indica-japonica hybrids in rice  

Microsoft Academic Search

Hybrid sterility is a major form of postzygotic reproductive isolation. Although reproductive isolation has been a key issue in evolutionary biology for many decades in a wide range of organisms, only very recently a few genes for reproductive isolation were identified. The Asian cultivated rice (Oryza sativa L.) is divided into two subspecies, indica and japonica. Hybrids between indica and

Jiongjiong Chen; Jihua Ding; Yidan Ouyang; Hongyi Du; Jiangyi Yang; Ke Cheng; Jie Zhao; Shuqing Qiu; Xuelian Zhang; Jialing Yao; Kede Liu; Lei Wang; Caiguo Xu; Xianghua Li; Yongbiao Xue; Mian Xia; Qing Ji; Jufei Lu; Mingliang Xu; Qifa Zhang

2008-01-01

65

Malaria vector control practices in an irrigated rice agro-ecosystem in central Kenya and implications for malaria control  

Microsoft Academic Search

Background  Malaria transmission in most agricultural ecosystems is complex and hence the need for developing a holistic malaria control\\u000a strategy with adequate consideration of socio-economic factors driving transmission at community level. A cross-sectional\\u000a household survey was conducted in an irrigated ecosystem with the aim of investigating vector control practices applied and\\u000a factors affecting their application both at household and community level.

Peter N Ng'ang'a; Josephat Shililu; Gayathri Jayasinghe; Violet Kimani; Charity Kabutha; Lucy Kabuage; Ephantus Kabiru; John Githure; Clifford Mutero

2008-01-01

66

13Carbon isotope discrimination in major C4 weeds of rice-implications for root interference studies  

Technology Transfer Automated Retrieval System (TEKTRAN)

Assessing below ground plant interference in rice has been difficult in the past because separation of intertwined weed and crop roots is nearly impossible. A simple 13C depletion method was previously developed for simultaneous quantification of barnyardgrass and rice roots in flooded fields. Thi...

67

Influence of the Asian Monsoon on net ecosystem carbon exchange in two major plant functional types in Korea  

NASA Astrophysics Data System (ADS)

Considering the feedback loops in radiation, temperature, and soil moisture with alterations in rainfall patterns, the influence of the changing monsoon on net ecosystem CO2 exchange can be critical to the estimation of carbon balance in Asia. In this paper, we examined the eddy covariance CO2 fluxes observed from 2004 to 2008 in two major plant functional types in KoFlux, i.e., the Gwangneung deciduous forest (GDK) site and the Haenam farmland (HFK) site. The objectives of the study were to (1) quantify the net ecosystem CO2 exchange (NEE), ecosystem respiration (RE), and gross primary production (GPP), (2) examine their interannual patterns, and (3) assess the mechanism for the coupling of carbon and water exchange associated with the summer monsoon. The GDK site, which had a maximum leaf area index (LAI) of ~5, was on average a relatively weak carbon sink with NEE of -84 gC m-2 y-1, RE of 1028 gC m-2 y-1, and GPP of 1113 gC m-2 y-1. Despite about 20% larger GPP (of 1321 gC m-2 y-1) in comparison with the GDK site, the HFK site (with the maximum LAI of 3 to 4) was a weaker carbon sink with NEE of -58 gC m-2 y-1 because of greater RE of 1263 gC m-2 y-1. In both sites, the annual patterns of NEE and GPP had a striking "mid-season depression" each year with two distinctive peaks of different timing and magnitude, whereas RE did not. The mid-season depression at the GDK site occurred typically from early June to late August, coinciding with the season of summer monsoon when the solar radiation decreased substantially due to frequent rainfalls and cloudiness. At the HFK site, the mid-season depression began earlier in May and continued until the end of July due to land use management (e.g., crop rotation) in addition to such disturbances as summer monsoon and typhoons. Other flux observation sites in East Asia also show a decline in radiation but with a lesser degree during the monsoon season, resulting in less pronounced depression in NEE. In our study, however, the observed depression in NEE changed the forest and farmland from a carbon sink to a source in the middle of the growing season. Consequently, the annually integrated values of NEE lies on the low end of the range reported in the literature. Such a delicate coupling between carbon and water cycles may turn these ecosystems into a stronger carbon sink with the projected trends of less frequent but more intensive rainfalls in this region.

Kwon, H.; Kim, J.; Hong, J.

2009-11-01

68

A major quantitative trait locus for rice yellow mottle virus resistance maps to a cluster of blast resistance genes on chromosome 12.  

PubMed

ABSTRACT Two doubled-haploid rice populations, IR64/Azucena and IRAT177/ Apura, were used to identify markers linked to rice yellow mottle virus (RYMV) resistance using core restriction fragment length polymorphism (RFLP) maps. Resistance was measured by mechanical inoculation of 19-day-old seedlings followed by assessment of virus content by enzyme-linked immunosorbent assay tests 15 days after inoculation. IR64/Azucena and IRAT177/Apura populations, 72 and 43 lines, respectively, were evaluated, and resistance was found to be polygenic. Resistance was expressed as a slower virus multiplication, low symptom expression, and limited yield loss when assessed at the field level. Bulked segregant analysis using the IR64/Azucena population identified a single random amplified polymorphic DNA marker that mapped on chromosome 12 and corresponded to a major quantitative trait locus (QTL) evidenced by interval mapping. When pooling RFLP data, integrated mapping of this chromosome revealed that the QTL was common to the two populations and corresponded to a small chromosomal segment known to contain a cluster of major blast resistance genes. This region of the genome also reflected the differentiation observed at the RFLP level between the subspecies indica and japonica of Oryza sativa. This is consistent with the observation that most sources of RYMV resistance used in rice breeding are found in upland rice varieties that typically belong to the japonica subspecies. PMID:18945025

Ghesquière, A; Albar, L; Lorieux, M; Ahmadi, N; Fargette, D; Huang, N; McCouch, S R; Notteghem, J L

1997-12-01

69

Change in T4-type bacteriophage communities during the composting process of rice straw: Estimation from the major capsid gene (g23) sequences  

Microsoft Academic Search

The present study examined T4-type phage communities in rice straw (RS) under the composting process by analyzing the composition of the major capsid gene (g23) of T4-type bacteriophages. The g23 clones were obtained from RS throughout the composting process from RS materials to composting RS in the curing stage (for 124?days). Most of the g23 clones were phylogenetically closely related

Vita Ratri Cahyani; Jun Murase; Susumu Asakawa; Makoto Kimura

2009-01-01

70

Genetic analysis and validation of quantitative trait loci associated with reproductive-growth traits and grain yield under drought stress in a doubled haploid line population of rice ( Oryza sativa L.)  

Microsoft Academic Search

Drought is a major constraint for rice production and yield stability in rainfed ecosystems, especially when it occurs during the reproductive stage. Combined genetic and physiological analysis of reproductive-growth traits and their effects on yield and yield components under drought stress is important for dissecting the biological bases of drought resistance and for rice yield improvement in water-limited environments. A

Reena Sellamuthu; Gui Fu Liu; Chandra Babu Ranganathan; Rachid Serraj

2011-01-01

71

Rice monoculture and integrated rice-fish farming in the Mekong Delta, Vietnam—economic and ecological considerations  

Microsoft Academic Search

This study is a survey of agriculture practices and pest management strategies among rice and rice-fish farmers in the Mekong Delta. Based on an economic comparison between different farmer categories, it is argued that rice-fish farming provides a sustainable alternative to rice monoculture, if the farmer takes full advantage of the natural productivity of the rice field ecosystem. The aim

Håkan Berg

2002-01-01

72

Overall effect of rice biomass and fish on the aquatic ecology of experimental rice plots  

Microsoft Academic Search

The integration of rice and fish culture promises ecologically sound and economically successful management of floodwater ecosystems. Amongst other benefits, the stocking of fish in rice fields may contribute to the soil fertility of the rice field. We investigated the impact of the rice biomass and the stocking of fish (a polyculture of Nile tilapia and common carp) on ammonium,

Nico Vromant; Nguyen Thi Hoai Chau

2005-01-01

73

Effect of rice hull ash silicon on rice seedling growth  

Microsoft Academic Search

Silicon (Si) promotes healthy development of rice plants. Research has shown that an adequate supply of Si to rice plants improves the plant resistance to abiotic and biotic stresses such as soil aluminum (Al) and manganese (Mn) toxicities and plant pest and diseases. Rice hull, a major by?product of rice milling, contains about 8% Si that can be recycled for

K. R. Sistani; N. K. Savant; K. C. Reddy

1997-01-01

74

RICE AND RED RICE INTERFERENCE: II. RICE RESPONSE TO POPULATION DENSITIES OF THREE RED RICE (ORYZA SATIVA) ECOTYPES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Red rice, which grows taller and produces more tillers than domestic rice and shatters most of its seeds early, is a major weed in many rice-growing areas of the world. Field experiments were conducted at Stuttgart, AR in 1997 and 1998 to evaluate the growth response of the Kaybonnet (KBNT) rice cul...

75

The effects of acid deposition on the biogeochemical cycles of major nutrients in miniature red spruce ecosystems  

Microsoft Academic Search

As part of an experimental study of air pollution effects on tree growth and health, we combined process studies with an ecosystem\\u000a approach to evaluate the effects of acidic deposition on soil acidification, nutrient cycling and proton fluxes in miniature\\u000a red spruce ecosystems. Ninety red spruce saplings were transplanted into 1-m diameter pots containing reconstructed soil profiles\\u000a and exposed to

Ruth E. Sherman; Timothy J. Fahey

1994-01-01

76

Quality Characteristics of Milled Rice Grown in Different Countries.  

National Technical Information Service (NTIS)

Next to yield, grain quality is the major objective of rice breeding programs. This report describes the quality characteristics of milled rice as assessed by IRRI's Chemistry Department since 1962. Rice samples were obtained from government rice breeding...

B. O. Juliano C. G. Pascual

1980-01-01

77

Changes in major capsid genes ( g23 ) of T4-type bacteriophages with soil depth in two Japanese rice fields  

Microsoft Academic Search

Although microbial communities in soil are well known to change with soil depth, the changes in viral communities with soil\\u000a depth have not been documented. This study examined the soil depth profiles of T4-type phage communities in two Japanese rice\\u000a fields from g23 clones in soil DNA extracts to a depth of 1 m. T4-type phage communities changed with soil depth,

Guanghua Wang; Jun Murase; Katsutoshi Taki; Yoshinori Ohashi; Nanako Yoshikawa; Susumu Asakawa; Makoto Kimura

2009-01-01

78

qDTY1.1, a major QTL for rice grain yield under reproductive-stage drought stress with a consistent effect in multiple elite genetic backgrounds  

PubMed Central

Background Drought is one of the most important abiotic stresses causing drastic reductions in yield in rainfed rice environments. The suitability of grain yield (GY) under drought as a selection criterion has been reported in the past few years. Most of the quantitative trait loci (QTLs) for GY under drought in rice reported so far has been in the background of low-yielding susceptible varieties. Such QTLs have not shown a similar effect in multiple high- yielding drought-susceptible varieties, thus limiting their use in marker-assisted selection. Genetic control of GY under reproductive-stage drought stress (RS) in elite genetic backgrounds was studied in three F3:4 mapping populations derived from crosses of N22, a drought-tolerant aus cultivar, with Swarna, IR64, and MTU1010, three high-yielding popular mega-varieties, with the aim to identify QTLs for GY under RS that show a consistent effect in multiple elite genetic backgrounds. Three populations were phenotyped under RS in the dry seasons (DS) of 2009 and 2010 at IRRI. For genotyping, whole-genome scans for N22/MTU1010 and bulked segregant analysis for N22/Swarna and N22/IR64 were employed using SSR markers. Results A major QTL for GY under RS, qDTY1.1, was identified on rice chromosome 1 flanked by RM11943 and RM431 in all three populations. In combined analysis over two years, qDTY1.1 showed an additive effect of 29.3%, 24.3%, and 16.1% of mean yield in N22/Swarna, N22/IR64, and N22/MTU1010, respectively, under RS. qDTY1.1 also showed a positive effect on GY in non-stress (NS) situations in N22/Swarna, N22/IR64 over both years, and N22/MTU1010 in DS2009. Conclusions This is the first reported QTL in rice with a major and consistent effect in multiple elite genetic backgrounds under both RS and NS situations. Consistency of the QTL effect across different genetic backgrounds makes it a suitable candidate for use in marker-assisted breeding.

2011-01-01

79

Research in Rice Fields  

USGS Publications Warehouse

Between 1987 and 1999, 2.4-3 million acres of rice were planted annually nationwide. Rice fields are a major component of the contemporary landscapes in the Gulf Coastal Plain, the Mississippi Alluvial Valley, and Central Valley of California. In 1998, approximately 600,000 acres of rice were planted in Louisiana. In the Louisiana plant commodities report for 1998, total value for rice was over $350 million; sugarcane was the only plant commodity that exceeded this value. Louisiana has over 2,000 rice farmers supporting over 12,000 jobs in the state. Rice fields in the United States receive high use by wildlife, especially shorebirds, wading birds, and waterfowl. Waterbirds use rice fields for food, shelter, and breeding habitat.

Geological Survey (U.S.)

2000-01-01

80

Effects of CO2 on Competition between Rice and Barnyardgrass.  

National Technical Information Service (NTIS)

The atmospheric CO2 concentration is increasing. Effects of elevated CO2 on rice production could occur not only through direct impacts to rice, but also indirectly via ecosystem responses. Changed competitiveness with elevated CO2 could occur between ric...

D. M. Olszyk L. L. Ranasinghe

1994-01-01

81

Effects of tillage during the nonwaterlogged period on nitrous oxide and nitric oxide emissions in typical Chinese rice-wheat rotation ecosystems  

NASA Astrophysics Data System (ADS)

Tillage practices result in major changes to soil environmental conditions and to the distribution of crop residues and nutrients in the soil profile, which may consequently affect the biogenic production and emission of N trace gases. To investigate the effects of tillage during the nonwaterlogged period on nitric oxide (NO) and nitrous oxide (N2O) emissions in rice-wheat rotation systems, we performed field experiments at three sites (Suzhou, Wuxi, and Jiangdu) in the Yangtze River Delta using static chamber techniques. The results showed that the effect of tillage on the emissions of both gases differed among the three field sites due to differences in agricultural management and soil texture. At the site with a light soil texture (Jiangdu: sandy loam), no tillage resulted in reduced NO emissions (0.5 kg N ha-1) as compared to conventionally tilled fields (0.9 kg N ha-1; p < 0.05). Regarding N2O, the no tillage plots showed significantly higher emissions (p < 0.05) in comparison to the tilled plots (3.9 versus 2.2 kg N ha-1) when the fields were merely amended with synthetic N fertilizers. However, this effect was not significant when wheat straw was used in addition to synthetic N fertilizers during the preceding rice season. In the clay loam soils (Wuxi), no tillage resulted in lower NO and higher N2O emissions from either N fertilized or unfertilized fields even though these results were not statistically significant. In the silty clay loam soils (Suzhou), which showed the highest soil organic carbon contents and the highest rates of N trace gas emissions in all three of the investigated sites, reduced tillage resulted in much higher NO emissions, whereas N2O emissions were not obviously influenced by tillage practices (reduced tillage versus tillage: NO, 9.5 versus 5.4 kg N ha-1; N2O, 10.6 versus 9.0 kg N ha-1). Similar effects of tillage were observed for the direct emission factors of the applied N during the wheat season. The observed emission factors for the different sites ranged from 0.3% to 2.4% for N2O (mean: 1.0%) and from 0.1% to 4.0% (mean: 0.9%) for NO, respectively. The observed site-to-site differences in emission factors are most likely the results of variations in soil properties (such as texture and pH) and agricultural practices (such as tillage and crop residue management) or in the amount and pattern of precipitation.

Yao, Zhisheng; Zhou, Zaixing; Zheng, Xunhua; Xie, Baohua; Liu, Chunyan; Butterbach-Bahl, Klaus; Zhu, Jianguo

2010-03-01

82

Genomic structure of weedy rice  

Technology Transfer Automated Retrieval System (TEKTRAN)

Weedy (red) rice is a major pest of cultivated rice in the United States (U.S.) and worldwide, causing decreases in both yield and market value. Previous work has shown that U.S. weedy rice is comprised of two genotypically distinct lineages that are strongly correlated with strawhull awnless (SH) ...

83

SEQUENCE-BASED ALIGNMENT OF SORGHUM CHROMOSOME 3 AND RICE CHROMOSOME 1 REVEALS EXTENSIVE CONSERVATION OF GENE ORDER AND ONE MAJOR CHROMOSOMAL REARRANGMENT  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this study, methods were developed for sequence-based alignment of sorghum and rice chromosomes and for refining the sorghum genome map based on the rice genome sequence. A framework of 135 contigs of large insert clones spanning 33 million base pairs was anchored to sorghum chromosome 3. A lim...

84

Productivity of Hybrid Rice: I. Vulnerability to Water Stress of Reproductive Development and Inhibition of RuBisCO Enzyme in Upper Leaves as Major Constraints to Yield  

Microsoft Academic Search

Producing more rice (Oryza sativa L.) with less water is a formidable challenge for the food, economic, social, and water security. To achieve this, the knowledge of how plant water stress is transduced into plant performance is necessary. The objective of this research was to investigate in hybrid rice the impact of soil water deficit, especially on reproductive growth and

Sanjay Singh; T. N. Singh; J. S. Chauhan

2010-01-01

85

Digital ecosystem ontology  

Microsoft Academic Search

Digital Ecosystems is a neoteric terminology and there are two major definitions about it respectively from Soluta.Net and from Digital Ecosystem and Business Intelligence Institute. In this paper, to solve the ambiguous problem in Digital Ecosystem's definitions and to help researchers better understand what it is, by means of ontology, we propose a conceptual model to completely illustrate the concepts

Hai Dong; Farookh Khadeer Hussain

2007-01-01

86

IDENTIFICATION OF BLAST RESISTANCE GENES IN INDICA RICE GERMPLASM  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rice blast caused by Pyricularia grisea (Cooke) Sacc., is a major fungal disease of cultivated rice (Oryza sativa L.) in the US, and of irrigated rice worldwide. Indica rice, rice grown in tropical areas is one possible source of additional blast resistance genes (Pi-genes) that could be incorporat...

87

EFFECTS OF CO2 ON COMPETITION BETWEEN RICE AND BARNYARDGRASS  

EPA Science Inventory

The atmospheric CO2 concentration is increasing. ffects of elevated CO2 on rice production could occur not only through direct impacts to rice, but also indirectly via ecosystem responses. hanged competitiveness with elevated CO2 could occur between rice hich has the C3 type of p...

88

Soil organic carbon (SOC) accumulation in rice paddies under long-term agro-ecosystem experiments in southern China - VI. Changes in microbial community structure and respiratory activity  

NASA Astrophysics Data System (ADS)

Biological stabilization within accumulated soil organic carbon (SOC) has not been well understood, while its role in physical and chemical protection as well as of chemical recalcitrance had been addressed in Chinese rice paddies. In this study, topsoil samples were collected and respiratory activity measured in situ following rice harvest under different fertilization treatments of three long-term experimental sites across southern China in 2009. The SOC contents, microbial biomass carbon (SMBC) and nitrogen (SMBN) were analysed using chemical digestion and microbial community structure assessment via clony dilute plate counting methods. While SOC contents were consistently higher under compound chemical fertilization (Comp-Fert) or combined organic and inorganic fertilization (Comb-Fert) compared to N fertilization only (N-Fert), there was significantly higher fungal-bacterial ratio under Comb-Fert than under N-Fert and Comp-Fert. When subtracting the background effect under no fertilization treatment (Non-Fert), the increase both in SMBC and SMBN under fertilization treatment was found very significantly correlated to the increase in SOC over controls across the sites. Also, the ratio of culturable fungal to bacterial population numbers (F/B ratio) was well correlated with soil organic carbon contents in all samples across the sites studied. SOC accumulation favoured a build-up the microbial community with increasing fungal dominance in the rice paddies under fertilization treatments. While soil respiration rates were high under Comb-Fert as a result of enhanced microbial community build-up, the specific soil respiratory activity based on microbial biomass carbon was found in a significantly negatively correlation with the SOC contents for overall samples. Thus, a fungal-dominated microbial community seemed to slow SOC turnover, thereby favouring SOC accumulation under Comp-Fert or under Comb-Fert in the rice paddies. Therefore, the biological stabilization process is of importance in SOC sequestration in the rice paddies, operating with physical and chemical protection and chemical recalcitrance. However, sufficient understanding and prediction of SOM dynamics needs further quantitative characterization of the simultaneous operation of several mechanisms.

Liu, D.; Liu, X.; Liu, Y.; Li, L.; Pan, G.; Crowley, D.; Tippkötter, R.

2011-02-01

89

Carbon cycling in rice field ecosystems in the context of input, decomposition and translocation of organic materials and the fates of their end products (CO 2 and CH 4)  

Microsoft Academic Search

Rice fields are intensively managed, unique agroecosystems, where soil flooding is general performance for rice cultivation. Flooding the field results in reductive soil conditions, under which decomposition of organic materials proceeds during the period of rice cultivation. A large variety of organic materials are incorporated into rice soils according to field management. In this review, the kind and abundance of

Makoto Kimura; Jun Murase; Yahai Lu

2004-01-01

90

Rice ESTs with disease-resistance gene- or defense-response gene-like sequences mapped to regions containing major resistance genes or QTLs.  

PubMed

The chromosomal locations of 109 rice expressed sequence tags (ESTs) in the rice genome were determined using a doubled haploid mapping population. These ESTs show high similarity to disease resistance genes or to defense response genes. Nine of the ESTs were mapped to three regions that contain genetically defined resistance genes on chromosomes 6 and 11. Clustering of the ESTs in the rice genome was observed at several chromosomal regions. Some of the clusters were located in regions where quantitative trait loci (QTL) associated with partial resistance to rice blast, bacterial blight and sheath blight are known to lie. Three ESTs that were mapped to the regions containing blast resistance genes Pi2 and Pia were chosen for Northern analysis after inoculation of plants with the blast fungus. Two of them, which code for a receptor-like kinase and a putative membrane channel protein, respectively, and were mapped to the Pi2 locus, were induced by rice blast infection as early as 4 h after inoculation. Transcription of another EST, which codes for a homolog of a putative human tumor suppressor and was mapped to the region containing Pia, was repressed after blast infection. These findings demonstrate that the candidate-gene approach is an efficient way of mapping resistance genes or resistance QTLs in rice. PMID:11361341

Wang, Z; Taramino, G; Yang, D; Liu, G; Tingey, S V; Miao, G H; Wang, G L

2001-04-01

91

What is a healthy ecosystem?  

Microsoft Academic Search

Rapid deterioration of the world's major ecosystems has intensified the need for effective environmental monitoring and the development of operational indicators of ecosystem health. Ecosystem health represents a desired endpoint of environmental management, but it requires adaptive, ongoing definition and assessment. We propose that a healthy ecosystem is one that is sustainable – that is, it has the ability to

Robert Costanza; Michael Mageau

1999-01-01

92

Evolutionary insights into the origins of weediness in U.S. red rice  

Technology Transfer Automated Retrieval System (TEKTRAN)

Weedy red rice is a widespread, economically challenging problem in Southern U.S. rice fields. The two major U.S. red rice types, strawhull and blackhull, are thought to have arisen independently from Asian rice populations in the distant past. Red rice is a weedy relative of rice, a genomic model...

93

[An evaluation of net carbon sink effect and cost/benefits of a rice-rape rotation ecosystem under long-term fertilization from Tai Lake region of China].  

PubMed

Taking a long-term fertilized rice-rape rotation system in Taihu Lake as test objective, its annual C balance and economic benefit were estimated, based on the measurement of past years grain yield, litter C content, and field CO2 emission as well as the investigation of material and management inputs. The calculated annual C sink under different fertilizations ranged from 0.9 t C x hm(-2) x a(-1) to 7.5 t C x hm(-2) x a(-1), and the net C sink effect under combined inorganic/organic fertilization was three folds as that under chemical fertilization. The C cost of material input ranged from 0.37 t C x hm(-2) x a(-1) to 1.13 t C x hm(-2) x a(-1), and that of management input ranged from 1.69 t C x hm(-2) x a(-1) to 1.83 t C x hm(-2) x a(-1). The annual economic benefit ranged from 5.8 x 10(3) CNY x hm(-2) x a(-1) to 16.5 x 10(3) CNY x hm(-2) x a(-1), and was 2.1 times higher under combined fertilization than under chemical fertilization. Comparing with that under chemical fertilization, the marginal cost for per ton C sink under combined inorganic/organic fertilization was estimated as 217.1 CNY x t(-1) C, very close to the C price of 20 Euro x t(-1) C in the EU. In sum, under combined inorganic/organic fertilization, this rice paddy ecosystem could not only have higher productivity, but also present greater net C sink effect and higher economic benefit, compared with under chemical fertilizer fertilization. PMID:19899468

Li, Jie-Jing; Pan, Gen-Xing; Zhang, Xu-Hui; Fei, Qing-Hua; Li, Zhi-Peng; Zhou, Ping; Zheng, Ju-Feng; Qiu, Duo-Sheng

2009-07-01

94

13Carbon isotope discrimination in roots and shoots of major weed species of southern U.S. rice fields and its potential use for analysis of rice-weed root interactions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Assessing below ground plant interference in rice has been difficult in the past because thorough, accurate separation of the intertwined roots of weed and crop is extremely challenging. A d13C depletion method has been developed to assess interactions between roots of barnyardgrass and weed-suppre...

95

Rice prairies  

USGS Publications Warehouse

Pesticide contamination of rice prairie waterfowl habitat and acute pesticide poisoning of wintering and migrating waterfowl on the rice prairies has been reduced in recent years. Some problems still exist.

Hobaugh, W.C.; Stutzenbaker, C.D.; Flickinger, E.L.

1989-01-01

96

The TIGR rice genome annotation resource: annotating the rice genome and creating resources for plant biologists  

Microsoft Academic Search

Rice is not only a major food staple for the world's population but it also is a model species for a major group of flowering plants, the monocotyledonous plants. Draft genomic sequence of two subspecies of rice, Oryza sativa spp. japonica and indica ssp. are publicly available. To provide the community with a resource to data-mine the rice genome, we

Qiaoping Yuan; Shu Ouyang; Jia Liu; Bernard Suh; Foo Cheung; Razvan Sultana; Daniel Lee; John Quackenbush; C. Robin Buell

2003-01-01

97

Root-to-shoot Cd translocation via the xylem is the major process determining shoot and grain cadmium accumulation in rice  

Microsoft Academic Search

Physiological properties involved in divergent cadmium (Cd) accumulation among rice genotypes were character- ized using the indica cultivar 'Habataki' (high Cd in grains) and the japonica cultivar 'Sasanishiki' (low Cd in grains). Time-dependence and concentration-dependence of symplastic Cd absorption in roots were revealed not to be responsible for the different Cd accumulation between the two cultivars because root Cd uptake

Shimpei Uraguchi; Shinsuke Mori; Masato Kuramata; Akira Kawasaki; Tomohito Arao; Satoru Ishikawa

2009-01-01

98

The broad-leaf herbicide 2,4-dichlorophenoxyacetic acid turns rice into a living trap for a major insect pest and a parasitic wasp.  

PubMed

Synthetic chemical elicitors of plant defense have been touted as a powerful means for sustainable crop protection. Yet, they have never been successfully applied to control insect pests in the field. We developed a high-throughput chemical genetics screening system based on a herbivore-induced linalool synthase promoter fused to a ?-glucuronidase (GUS) reporter construct to test synthetic compounds for their potential to induce rice defenses. We identified 2,4-dichlorophenoxyacetic acid (2,4-D), an auxin homolog and widely used herbicide in monocotyledonous crops, as a potent elicitor of rice defenses. Low doses of 2,4-D induced a strong defensive reaction upstream of the jasmonic acid and ethylene pathways, resulting in a marked increase in trypsin proteinase inhibitor activity and volatile production. Induced plants were more resistant to the striped stem borer Chilo suppressalis, but became highly attractive to the brown planthopper Nilaparvata lugens and its main egg parasitoid Anagrus nilaparvatae. In a field experiment, 2,4-D application turned rice plants into living traps for N. lugens by attracting parasitoids. Our findings demonstrate the potential of auxin homologs as defensive signals and show the potential of the herbicide to turn rice into a selective catch crop for an economically important pest. PMID:22313362

Xin, Zhaojun; Yu, Zhaonan; Erb, Matthias; Turlings, Ted C J; Wang, Baohui; Qi, Jinfeng; Liu, Shengning; Lou, Yonggen

2012-02-07

99

Biodegradation of Clomazone in a California Rice Field Soil: Carbon Allocation and Community Effects.  

PubMed

Degradation pathways for the herbicide clomazone in a California rice field soil were characterized via pulse-labeling of anaerobic (flooded) and aerobic (moist) soil microcosms. Clomazone-derived (13)C in the major C pools of a rice ecosystem and soil phospholipid fatty acid (PLFA) profiles were analyzed over time to determine if (1) the compound accumulates in the microbial biomass, (2) it affects temporal microbial population dynamics, and (3) it is either preferentially metabolized or cometabolized. In anaerobic microcosms, the compound was rapidly biotransformed to ring-open clomazone, upon which it persisted in the aqueous phase, whereas aerobic microcosms degraded it slower but a greater percentage was mineralized. Anaerobic biomass decreased after clomazone was added, and aerobic actinomycete abundance differed between treatments and controls. Additionally, PLFA and (13)C PLFA were statistically similar between treatment and controls. Thus, microbial cometabolism is likely to be the dominant degrading mechanism governing clomazone fate in California rice fields. PMID:23432155

Tomco, Patrick L; Holmes, William E; Tjeerdema, Ronald S

2013-03-01

100

Background for 1985 Farm Legislation: Rice.  

National Technical Information Service (NTIS)

Rice ranks ninth among major field crops in value of production. All U.S. rice production is irrigated, providing more stable yields than many other crops. Three classes of U.S. rice are produced--long, medium, and short grain--with long grain predominant...

1984-01-01

101

Genetic, Molecular and Genomic Basis of Rice Defense against Insects  

Microsoft Academic Search

Rice is the world's most important staple crop, feeding more than half of the world's population. Insects and other arthropods present an important constraint in rice production. This paper begins with an introduction to major insect pests of rice and their impact, followed by a description of some of the approaches currently used in insect management programs of rice. Then

Hao Chen; Michael J. Stout; Qian Qian; Feng Chen

2012-01-01

102

Impact of six transgenic Bacillus thuringiensis rice lines on four nontarget thrips species attacking rice panicles in the paddy field.  

PubMed

As a key component of ecological risk assessments, nontarget effects of Bacillus thuringiensis (Bt) rice have been tested under laboratory and field conditions for various organisms. A 2-yr field experiment was conducted to observe the nontarget effects of six transgenic rice lines (expressing the Cry1Ab or fused protein of Cry1Ab and Cry1Ac) on four nontarget thrips species including Frankliniella intonsa (Trybom), F. tenuicornis (Uzel), Haplothrips aculeatus (F.), and H. tritici (Kurd), as compared with their rice parental control lines. Two sampling methods including the beat plate and plastic bag method were used to monitor the population densities of the four thrips species for 2 yr. The results showed that the seasonal average densities of four tested thrips species in Bt rice plots were significantly lower than or very similar to those in the non-Bt rice plots depending on rice genotypes, sampling methods, and years. Among all six tested Bt rice lines, transgenic B1 and KMD2 lines suppressed the population of these tested thrips species the most. Our results indicate that the tested Bt rice lines are unlikely to result in high population pressure of thrips species in comparison with non-Bt rice. In some cases, Bt rice lines could significantly suppress thrips populations in the rice ecosystem. In addition, compatibility of Bt rice, with rice host plant resistance to nontarget sucking pests is also discussed within an overall integrated pest management program for rice. PMID:23339799

Akhtar, Z R; Tian, J C; Chen, Y; Fang, Q; Hu, C; Peng, Y F; Ye, G Y

2013-02-01

103

THE HEART PROJECT: DETERMINING HOW THE MAJOR AGRICULTURAL ECOSYSTEM OF THE U.S. WILL RESPOND TO ATMOSPHERIC CHANGE IN 2050  

Technology Transfer Automated Retrieval System (TEKTRAN)

Our atmosphere is changing. Concentrations of both carbon dioxide ([CO2]) and ozone ([O3]) in the atmosphere have increased and will continue to do so. This may dramatically affect the Corn Belt, with important economic and climatic consequences. The 'Heartland Ecosystem and its Adaptation, Response...

104

IMPACT OF EDUCATION ON KNOWLEDGE, AGRICULTURAL PRACTICES, AND COMMUNITY ACTIONS FOR MOSQUITO CONTROL AND MOSQUITO-BORNE DISEASE PREVENTION IN RICE ECOSYSTEMS IN SRI LANKA  

Microsoft Academic Search

Mosquito-borne diseases are a major public health threat in Sri Lanka. A 20-week pilot education program to improve community knowledge and mosquito control with participatory and non-chemical approaches was developed, implemented, and evaluated using pre-educational and post-educational surveys in two intervention and two comparison villages. Correlates of baseline knowledge were sex, number of family members, ratio of family members with

JUNKO YASUOKA; THOMAS W. MANGIONE; ANDREW SPIELMAN; RICHARD LEVINS

2006-01-01

105

Point Mutations with Positive Selection Were a Major Force during the Evolution of a Receptor-Kinase Resistance Gene Family of Rice1[W  

PubMed Central

The rice (Oryza sativa) Xa26 gene, which confers resistance to bacterial blight disease and encodes a leucine-rich repeat (LRR) receptor kinase, resides at a locus clustered with tandem homologous genes. To investigate the evolution of this family, four haplotypes from the two subspecies of rice, indica and japonica, were analyzed. Comparative sequence analysis of 34 genes of 10 types of paralogs of the family revealed haplotype polymorphisms and pronounced paralog diversity. The orthologs in different haplotypes were more similar than the paralogs in the same haplotype. At least five types of paralogs were formed before the separation of indica and japonica subspecies. Only 7% of amino acid sites were detected to be under positive selection, which occurred in the extracytoplasmic domain. Approximately 74% of the positively selected sites were solvent-exposed amino acid residues of the LRR domain that have been proposed to be involved in pathogen recognition, and 73% of the hypervariable sites detected in the LRR domain were subject to positive selection. The family is formed by tandem duplication followed by diversification through recombination, deletion, and point mutation. Most variation among genes in the family is caused by point mutations and positive selection.

Sun, Xinli; Cao, Yinglong; Wang, Shiping

2006-01-01

106

Contribution of Rice Field Ecosytems to Food Security Strategies in Northwest Cambodia  

Microsoft Academic Search

Rich in biodiversity, Cambodia's rice field ecosystems are an important source of livelihood and food security. Foraging of aquatic plants and animals alongside the cultivation of rice has been the main characteristic of food and income systems of traditional Cambodian rural society. Participatory action learning involving 30 farmers in three different villages located in three different lowland ecosystems of northwest

Numa Shams

2007-01-01

107

Depletion of plant?available silicon in soils: A possible cause of declining rice yields  

Microsoft Academic Search

The phenomenon of yield decline in different rice ecosystems from many parts of the world has been reported to be associated with decreases in the effective nitrogen (N) supply from soil. However, many reports in the literature suggest that silicon (Si) is an agronomically essential element for sustainable rice production. Depletion of plant?available Si in soils where rice is grown

Narayan K. Savant; Lawrence E. Datnoff; George H. Snyder

1997-01-01

108

Identification of possible technical problems in determination of the major inorganic constituents of brown-rice flour by evaluating proficiency test results.  

PubMed

To support skill upgrading in analysis of inorganic constituents of environmental and food samples, the National Metrology Institute of Japan (NMIJ) and the National Food Research Institute (NFRI) have organized a proficiency test (PT) of determination of Mn, Fe, Cu, Zn, As, and Cd in brown-rice flour based on the international standard (ISO/IEC 17043:2010). One hundred and thirty-three sets of reports were assessed by use of the E n -number and z-score approaches in accordance with ISO/IEC 17043 and the international harmonized protocol for PT. The PT results and analytical procedures, reported in detail, were reviewed, and possible technical reasons for questionable or unsatisfactory results are discussed. PMID:23907683

Miyashita, Shin-Ichi; Inagaki, Kazumi; Naito, Shigehiro; Shindoh, Kumiko; Narukawa, Tomohiro; Zhu, Yanbei; Kuroiwa, Takayoshi; Hioki, Akiharu; Fujimoto, Toshiyuki; Chiba, Koichi

2013-08-02

109

A variegated meadowhawk dragonfly (Sympetrum corruptum) perches in a California rice field.  

NSDL National Science Digital Library

A variegated meadowhawk dragonfly (Sympetrum corruptum) perches in a California rice field. Rice fields are widespread agricultural ecosystems that provide habitat for many wetland species, such as dragonflies. Management choices made in rice production may also influence adjacent communities. Rice fields can be used as models to understand how nutrients affect food web dynamics in seasonal wetlands. This photograph originally appeared on the cover of Ecological Applications (15:4) in December of 2005.

Lawler, Sharon P.

2010-02-11

110

Interaction of beggiatoa and rice plant: detoxification of hydrogen sulfide in the rice rhizosphere.  

PubMed

Beggiatoa was obtained from six habitats, including four water-saturated soils from rice fields. The isolate of Beggiatoa from Bernard clay, when reinoculated into soil treatments from pure culture, significantly reduced hydrogen sulfide levels in soils and increased oxygen release from rice plants. Rice plants significantly increased Beggiatoa survival in flooded soils. Some hydrogen sulfide was necessary for survival of the Bernard clay isolate; high concentrations of hydrogen sulfide killed the Bernard clay isolate but were tolerated by a Crowley silt loam isolate from Eagle Lake, Texas. The results suggest that Beggiatoa may be an element of wetlands plant ecosystems. PMID:17844038

Joshi, M M; Hollis, J P

1977-01-14

111

Thermomechanical property of rice kernels studied by DMA  

Technology Transfer Automated Retrieval System (TEKTRAN)

The thermomechanical property of the rice kernels was investigated using a dynamic mechanical analyzer (DMA). The length change of rice kernel with a loaded constant force along the major axis direction was detected during temperature scanning. The thermomechanical transition occurred in rice kernel...

112

Origin, dispersal, cultivation and variation of rice.  

PubMed

There are two cultivated and twenty-one wild species of genus Oryza. O. sativa, the Asian cultivated rice is grown all over the world. The African cultivated rice, O. glaberrima is grown on a small scale in West Africa. The genus Oryza probably originated about 130 million years ago in Gondwanaland and different species got distributed into different continents with the breakup of Gondwanaland. The cultivated species originated from a common ancestor with AA genome. Perennial and annual ancestors of O. sativa are O. rufipogon and O. nivara and those of O. glaberrima are O. longistaminata, O. breviligulata and O. glaberrima probably domesticated in Niger river delta. Varieties of O. sativa are classified into six groups on the basis of genetic affinity. Widely known indica rices correspond to group I and japonicas to group VI. The so called javanica rices also belong to group VI and are designated as tropical japonicas in contrast to temperate japonicas grown in temperate climate. Indica and japonica rices had a polyphyletic origin. Indicas were probably domesticated in the foothills of Himalayas in Eastern India and japonicas somewhere in South China. The indica rices dispersed throughout the tropics and subtropics from India. The japonica rices moved northward from South China and became the temperate ecotype. They also moved southward to Southeast Asia and from there to West Africa and Brazil and became tropical ecotype. Rice is now grown between 55 degrees N and 36 degrees S latitudes. It is grown under diverse growing conditions such as irrigated, rainfed lowland, rainfed upland and floodprone ecosystems. Human selection and adaptation to diverse environments has resulted in numerous cultivars. It is estimated that about 120,000 varieties of rice exist in the world. After the establishment of International Rice Research Institute in 1960, rice varietal improvement was intensified and high yielding varieties were developed. These varieties are now planted to 70% of world's riceland. Rice production doubled between 1966 and 1990 due to large scale adoption of these improved varieties. Rice production must increase by 60% by 2025 to feed the additional rice consumers. New tools of molecular and cellular biology such as anther culture, molecular marker aided selection and genetic engineering will play increasing role in rice improvement. PMID:9291957

Khush, G S

1997-09-01

113

AQUATIC ECOSYSTEMS,  

EPA Science Inventory

Aquatic ecosystems are a vital part of the urban water cycle (and of urban areas more broadly), and, if healthy, provide a range of goods and services valued by humans (Meyer 1997). For example, aquatic ecosystems (e.g., rivers, lakes, wetlands) provide potable water, food resou...

114

The rice root-knot nematode, Meloidogyne graminicoZa, on deep water rice (Qryza sativa subsp. indica)  

Microsoft Academic Search

SUMMARY In a series of experiments designed to simulate deep water rice growing conditions, Meloidogyne gralninicola Golden & Birchfield was found to survive in flooded soils and cause serious damage to cultivars of deep water rice from Bangladesh. M. graminicola significantly reduced growth of deep water rice before flooding and to a greater extent after flooding. On submergence, the majority

Sam L. J. PAGE

115

ASSESSMENT OF THE EFFECT OF CLIMATE CHANGE ON BORO RICE PRODUCTION IN BANGLADESH USING CERES-RICE MODEL  

Microsoft Academic Search

Effect of climate change on yield of two varieties of boro rice has been assessed using the CERES- Rice model of the DSSAT modeling system. The yield of BR3 and BR14 boro varieties for the years 2008, 2030, 2050 and 2070 have been simulated for 12 locations (districts) of Bangladesh, which were selected from among the major rice growing areas

Jayanta Kumar Basak; M. Ashraf Ali

116

Phylogenetic diversity and assemblage of major capsid genes (g23) of T4-type bacteriophages in paddy field soils during rice growth season in Northeast China  

Microsoft Academic Search

Although bacteriophages (phages) are ubiquitous and the most abundant biological entities on Earth, the genetic information on their diversity and community composition in natural environments, particularly in soils, is limited. This study elucidated the diversity and composition of T4-type phages by analyzing partial major capsid gene (g23) sequences in DNA extracts from five paddy field soils in Northeast China during

Junjie Liu; Guanghua Wang; Qiang Wang; Judong Liu; Jian Jin; Xiaobing Liu

2012-01-01

117

Methane emission estimates from rice fields using ground truths and GIS/ RS approach for Karnal in Haryana-India  

NASA Astrophysics Data System (ADS)

Methane (CH4 ) is an important atmospheric greenhouse gas and has been estimated to account for 15-20 % of current radiative forcing. Rice cultivation has been identified as one of the important anthropogenic sources of CH4 and the type of water regime has been a major source of uncertainty in CH4 emission estimates and has direct bearing on its emissions. The present study aims to fill the gaps in uncertainty by adopting RS/ GIS based approach for the rice acreage estimation under different water regimes, so as to obtain CH4 emission estimates at the block level for Karnal district in Haryana state of India, using water regime specific methane emission factors (EF) generated from earlier emission data without any organic amendments and for low soil organic carbon. Total rice area was estimated using IRS LISS III - P6 satellite data of kharif season 2006. A survey was done from the rice-growing farmers across the village clusters of 3 blocks (Indri, Karnal and Nilokheri) of Karnal district, to capture the spatial variability of water regimes and its corresponding layer has been generated in GIS using inverse distance weightage (IDW) interpolation. The resulting spatial variability of water regimes was 42, 44 and 14% for MA, SA and CF, respectively. The overlay and intersection of thematic layer of rice crop with the water regime and administrative block boundary layers was done using GIS tools to arrive at the rice area under different water regimes at block level for Karnal. The annual CH4 emission from paddy fields of 3 blocks of Karnal district was estimated, using IPCC-1997 methodology, as the product of the rice area under each water regime of paddy growing ecosystem with the corresponding CH4 emission factors, at block level. The total budget, which is the sum of emissions, from each water regime at block level, was estimated to be 5.14 + 1.7 Gg y-1 .

Gupta, Prabhat; Gupta, Vandana; Chandna, Parvesh; Kumar, Krishan; Ladha, J. K.

118

Ecosystem Valuation  

NSDL National Science Digital Library

Developed as a collaborative project of the US Department of Agriculture, Natural Resource Conservation Service, US Department of Commerce, NOAA-Sea Grant Office, and University of Maryland, Center for Environmental Science, this new Website examines how economists attempt to assign values to ecosystem services. The site is well organized and outlines general and specific topics under the following sections: The Big Picture, Essentials of Ecosystem Valuation, Dollar-based Ecosystem Valuation Methods, Ecosystem Benefit Indicators, and Links. Topics are explained in terms that laypersons will understand (a glossary is also provided) but without compromising the quality of information. Anyone interested in learning more about this controversial but increasingly important area will find this site an excellent starting point.

119

Antarctic Ecosystem  

NSDL National Science Digital Library

In contrast with its largely lifeless interior, the Antarctic coastal marine environment supports a vibrant and diverse ecosystem. Explore the region's living bounty in this interactive activity adapted from the Woods Hole Oceanographic Institution.

Foundation, Wgbh E.

2008-01-17

120

Saltwater Ecosystems  

Microsoft Academic Search

\\u000a Add some water to a terrestrial ecosystem and you can expect a boost in productivity. It is, after all, essential for life;\\u000a most land-based creatures live their lives with only a small tolerance for desiccation. Now add more water, so that the ecosystem\\u000a is periodically or permanently flooded. This is too much water for many organisms, and it will quickly

Douglas J. Spieles

121

Comparative Analyses Between Lolium/Festuca Introgression Lines and Rice Reveal the Major Fraction of Functionally Annotated Gene Models Is Located in Recombination-Poor/Very Recombination-Poor Regions of the Genome  

PubMed Central

Publication of the rice genome sequence has allowed an in-depth analysis of genome organization in a model monocot plant species. This has provided a powerful tool for genome analysis in large-genome unsequenced agriculturally important monocot species such as wheat, barley, rye, Lolium, etc. Previous data have indicated that the majority of genes in large-genome monocots are located toward the ends of chromosomes in gene-rich regions that undergo high frequencies of recombination. Here we demonstrate that a substantial component of the coding sequences in monocots is localized proximally in regions of very low and even negligible recombination frequencies. The implications of our findings are that during domestication of monocot plant species selection has concentrated on genes located in the terminal regions of chromosomes within areas of high recombination frequency. Thus a large proportion of the genetic variation available for selection of superior plant genotypes has not been exploited. In addition our findings raise the possibility of the evolutionary development of large supergene complexes that confer a selective advantage to the individual.

King, Julie; Armstead, Ian P.; Donnison, S. Iain; Roberts, Luned A.; Harper, John A.; Sk?t, Kirsten; Elborough, Kieran; King, Ian P.

2007-01-01

122

Comparative analyses between lolium/festuca introgression lines and rice reveal the major fraction of functionally annotated gene models is located in recombination-poor/very recombination-poor regions of the genome.  

PubMed

Publication of the rice genome sequence has allowed an in-depth analysis of genome organization in a model monocot plant species. This has provided a powerful tool for genome analysis in large-genome unsequenced agriculturally important monocot species such as wheat, barley, rye, Lolium, etc. Previous data have indicated that the majority of genes in large-genome monocots are located toward the ends of chromosomes in gene-rich regions that undergo high frequencies of recombination. Here we demonstrate that a substantial component of the coding sequences in monocots is localized proximally in regions of very low and even negligible recombination frequencies. The implications of our findings are that during domestication of monocot plant species selection has concentrated on genes located in the terminal regions of chromosomes within areas of high recombination frequency. Thus a large proportion of the genetic variation available for selection of superior plant genotypes has not been exploited. In addition our findings raise the possibility of the evolutionary development of large supergene complexes that confer a selective advantage to the individual. PMID:17603095

King, Julie; Armstead, Ian P; Donnison, S Iain; Roberts, Luned A; Harper, John A; Skøt, Kirsten; Elborough, Kieran; King, Ian P

2007-07-01

123

Molecular evidence for a single evolutionary origin of domesticated rice  

PubMed Central

Asian rice, Oryza sativa, is one of world's oldest and most important crop species. Rice is believed to have been domesticated ?9,000 y ago, although debate on its origin remains contentious. A single-origin model suggests that two main subspecies of Asian rice, indica and japonica, were domesticated from the wild rice O. rufipogon. In contrast, the multiple independent domestication model proposes that these two major rice types were domesticated separately and in different parts of the species range of wild rice. This latter view has gained much support from the observation of strong genetic differentiation between indica and japonica as well as several phylogenetic studies of rice domestication. We reexamine the evolutionary history of domesticated rice by resequencing 630 gene fragments on chromosomes 8, 10, and 12 from a diverse set of wild and domesticated rice accessions. Using patterns of SNPs, we identify 20 putative selective sweeps on these chromosomes in cultivated rice. Demographic modeling based on these SNP data and a diffusion-based approach provide the strongest support for a single domestication origin of rice. Bayesian phylogenetic analyses implementing the multispecies coalescent and using previously published phylogenetic sequence datasets also point to a single origin of Asian domesticated rice. Finally, we date the origin of domestication at ?8,200–13,500 y ago, depending on the molecular clock estimate that is used, which is consistent with known archaeological data that suggests rice was first cultivated at around this time in the Yangtze Valley of China.

Molina, Jeanmaire; Sikora, Martin; Garud, Nandita; Flowers, Jonathan M.; Rubinstein, Samara; Reynolds, Andy; Huang, Pu; Jackson, Scott; Schaal, Barbara A.; Bustamante, Carlos D.; Boyko, Adam R.; Purugganan, Michael D.

2011-01-01

124

The genetics of domestication of rice bean, Vigna umbellata  

PubMed Central

Background and Aims The Asian genus Vigna, to which four cultivated species (rice bean, azuki bean, mung bean and black gram) belong, is suitable for comparative genomics. The aims were to construct a genetic linkage map of rice bean, to identify the genomic regions associated with domestication in rice bean, and to compare these regions with those in azuki bean. Methods A genetic linkage map was constructed by using simple sequence repeat and amplified fragment length polymorphism markers in the BC1F1 population derived from a cross between cultivated and wild rice bean. Using this map, 31 domestication-related traits were dissected into quantitative trait loci (QTLs). The genetic linkage map and QTLs of rice bean were compared with those of azuki bean. Key Results A total of 326 markers converged into 11 linkage groups (LGs), corresponding to the haploid number of rice bean chromosomes. The domestication-related traits in rice bean associated with a few major QTLs distributed as clusters on LGs 2, 4 and 7. A high level of co-linearity in marker order between the rice bean and azuki bean linkage maps was observed. Major QTLs in rice bean were found on LG4, whereas major QTLs in azuki bean were found on LG9. Conclusions This is the first report of a genetic linkage map and QTLs for domestication-related traits in rice bean. The inheritance of domestication-related traits was so simple that a few major QTLs explained the phenotypic variation between cultivated and wild rice bean. The high level of genomic synteny between rice bean and azuki bean facilitates QTL comparison between species. These results provide a genetic foundation for improvement of rice bean; interchange of major QTLs between rice bean and azuki bean might be useful for broadening the genetic variation of both species.

Isemura, Takehisa; Kaga, Akito; Tomooka, Norihiko; Shimizu, Takehiko; Vaughan, Duncan Alexander

2010-01-01

125

Arsenic in Rice and Rice Products  

Center for Food Safety and Applied Nutrition (CFSAN)

... Arsenic in Rice and Rice Products Arsenic is present in the environment as a naturally occurring substance or as a result of contamination from ... More results from www.fda.gov/food/foodborneillnesscontaminants/metals

126

Soil clay contributing to determination of growing period in rainfed lowland rice  

Microsoft Academic Search

Rainfed lowland rice ecosystems in the Mekong region receive high annual rainfall, but the rice plants often encounter drought throughout the growing season because coarse-textured soils have large water losses due to deep percolation. Field water availability during the growing season, and the length of growing period (LGP) are measures used to provide the geographical dimensions of soil hydrological patterns

Thavone Inthavong; Mitsuru Tsubo; Shu Fukai

127

MANAGING TROPICAL RICE PESTS THROUGH CONSERVATION OF GENERALIST NATURAL ENEMIES AND ALTERNATIVE PREY1  

Microsoft Academic Search

The cultivation of tropical Asian rice, which may have originated 9000 yr ago, represents an agricultural ecosystem of unrivaled ecological complexity. We undertook a study of the community ecology of irrigated tropical rice fields on Java, Indonesia, as a supporting study for the Indonesian National Integrated Pest Management Programme, whose purpose is to train farmers to be better agronomists and

WILLIAM H. SETTLE; HARTIAHYO ARIAWAN; ARIEF LUKMAN HAKIM; DADAN HINDAYANA; SRI LESTARI

1996-01-01

128

EFFECTS OF UV-B AND GLOBAL CLIMATE CHANGE ON RICE RESEARCH PLAN  

EPA Science Inventory

Little is currently known about the response of rice plants to UV-B radiation, enriched CO2, or elevated temperature. ven less is known about the responses of important rice ecosystem components (pests, pathogens, weeds, nitrogen fixation, methanogenesis) to these factors. o accu...

129

Rice domestication: histories and mysteries.  

PubMed

Domesticated rice (Oryza sativa) is one of the world's most important food crops, culturally, nutritionally and economically (Khush 1997). Thus, it is no surprise that there is intense curiosity about its genetic and geographical origins, its response to selection under domestication, and the genetic structure of its wild relative, Oryza rufipogon. Studies of Oryza attempting to answer these questions have accompanied each stage of the development of molecular markers, starting with allozymes and continuing to genome sequencing. While many of these studies have been restricted to small sample sizes, in terms of either the number of markers used or the number and distribution of the accessions, costs are now low enough that researchers are including large numbers of molecular markers and accessions. How will these studies relate to previous findings and long-held assumptions about rice domestication and evolution? If the paper in this issue of Molecular Ecology (Huang et al. 2012) is any indication, there will be some considerable surprises in store. In this study, a geographically and genomically thorough sampling of O. rufipogon and O. sativa revealed two genetically distinct groups of wild rice and also indicated that only one of these groups appears to be related to domesticated rice. While this fits well with previous studies indicating that there are genetic subdivisions within O. rufipogon, it stands in contrast to previous findings that the two major varieties of O. sativa (indica and japonica) were domesticated from two (or more) subpopulations of wild rice. PMID:22967059

Gross, Briana L

2012-09-01

130

Bioengineered 'golden' indica rice cultivars with beta-carotene metabolism in the endosperm with hygromycin and mannose selection systems.  

PubMed

Vitamin-A deficiency (VAD) is a major malnutrition problem in South Asia, where indica rice is the staple food. Indica-type rice varieties feed more than 2 billion people. Hence, we introduced a combination of transgenes using the biolistic system of transformation enabling biosynthesis of provitamin A in the endosperm of several indica rice cultivars adapted to diverse ecosystems of different countries. The rice seed-specific glutelin promoter (Gt-1 P) was used to drive the expression of phytoene synthase (psy), while lycopene beta-cyclase (lcy) and phytoene desaturase (crtI), fused to the transit peptide sequence of the pea-Rubisco small subunit, were driven by the constitutive cauliflower mosaic virus promoter (CaMV35S P). Transgenic plants were recovered through selection with either CaMV35S P driven hph (hygromycin phosphotransferase) gene or cestrum yellow leaf curling virus promoter (CMP) driven pmi (phophomannose isomerase) gene. Molecular and biochemical analyses demonstrated stable integration and expression of the transgenes. The yellow colour of the polished rice grain evidenced the carotenoid accumulation in the endosperm. The colour intensity correlated with the estimated carotenoid content by spectrophotometric and HPLC analysis. Carotenoid level in cooked polished seeds was comparable (with minor loss of xanthophylls) to that in non-cooked seeds of the same transgenic line. The variable segregation pattern in T1 selfing generation indicated single to multiple loci insertion of the transgenes in the genome. This is the first report of using nonantibiotic pmi driven by a novel promoter in generating transgenic indica rice for possible future use in human nutrition. PMID:17147745

Datta, Karabi; Baisakh, Niranjan; Oliva, Norman; Torrizo, Lina; Abrigo, Editha; Tan, Jing; Rai, Mayank; Rehana, Sayda; Al-Babili, Salim; Beyer, Peter; Potrykus, Ingo; Datta, Swapan K

2003-03-01

131

Desert Ecosystems  

NSDL National Science Digital Library

The Desert Ecosystems site describes the geology and climate, plants and animals, and cultural history of the main U.S. desert regions including: the Mojave Desert, the Great Basin, and the Colorado/Sonoran desert. There are also descriptions and photos of water in the desert, coyotes, the desert tortoise, and the creosote bush.

132

Digital Ecosystems: Ecosystem-Oriented Architectures  

Microsoft Academic Search

We view Digital Ecosystems to be the digital counterparts of biological ecosystems. Here, we are concerned with the creation\\u000a of these Digital Ecosystems, exploiting the self-organising properties of biological ecosystems to evolve high-level software\\u000a applications. Therefore, we created the Digital Ecosystem, a novel optimisation technique inspired by biological ecosystems,\\u000a where the optimisation works at two levels: a first optimisation, migration

Gerard Briscoe; Suzanne Sadedin; Philippe De Wilde

2011-01-01

133

SOME PHYSIOLOGTICAL AND COMPETITIVE ADVANTAGES OF RED RICE OVER RICE  

Technology Transfer Automated Retrieval System (TEKTRAN)

In the southern U.S. and other rice-producing countries, red rice (Oryza sativa) is a troublesome weed in rice production. Red rice is highly competitive, reduces harvesting efficiency, and contaminates harvested grain with red kernels. Red rice problem spurs the herbicide-resistant rice (Clearfie...

134

SFRSF: Our Coastal Ecosystems  

NSDL National Science Digital Library

This South Florida Restoration Science Forum (SFRSF) page highlights the coastal ecosystems of southern Florida. Research displayed from poster presentations covers the coastal area habitats, sustaining and enhancing coastal waters, major coastal challenges, restoring and enhancing estuaries, and using science for effective resource management. The six estuaries discussed are the Caloosahatchee, Southwest Florida, Biscayne Bay, Florida Bay, Florida Keys, and St. Lucie estuaries. Specific issues concerning each estuary are covered, and links are provided for additional information.

135

Tolerance of anaerobic conditions caused by flooding during germination and early growth in rice (Oryza sativa L.)  

PubMed Central

Rice is semi-aquatic, adapted to a wide range of hydrologies, from aerobic soils in uplands to anaerobic and flooded fields in waterlogged lowlands, to even deeply submerged soils in flood-prone areas. Considerable diversity is present in native rice landraces selected by farmers over centuries. Our understanding of the adaptive features of these landraces to native ecosystems has improved considerably over the recent past. In some cases, major genes associated with tolerance have been cloned, such as SUB1A that confers tolerance of complete submergence and SNORKEL genes that control plant elongation to escape deepwater. Modern rice varieties are sensitive to flooding during germination and early growth, a problem commonly encountered in rainfed areas, but few landraces capable of germination under these conditions have recently been identified, enabling research into tolerance mechanisms. Major QTLs were also identified, and are being targeted for molecular breeding and for cloning. Nevertheless, limited progress has been made in identifying regulatory processes for traits that are unique to tolerant genotypes, including faster germination and coleoptile elongation, formation of roots and leaves under hypoxia, ability to catabolize starch into simple sugars for subsequent use in glycolysis and fermentative pathways to generate energy. Here we discuss the state of knowledge on the role of the PDC-ALDH-ACS bypass and the ALDH enzyme as the likely candidates effective in tolerant rice genotypes. Potential involvement of factors such as cytoplasmic pH regulation, phytohormones, reactive oxygen species scavenging and other metabolites is also discussed. Further characterization of contrasting genotypes would help in elucidating the genetic and biochemical regulatory and signaling mechanisms associated with tolerance. This could facilitate breeding rice varieties suitable for direct seeding systems and guide efforts for improving waterlogging tolerance in other crops.

Miro, Berta; Ismail, Abdelbagi M.

2013-01-01

136

Climate Change: Implications for the Yield of Edible Rice  

PubMed Central

Global warming affects not only rice yield but also grain quality. A better understanding of the effects of climate factors on rice quality provides information for new breeding strategies to develop varieties of rice adapted to a changing world. Chalkiness is a key trait of physical quality, and along with head rice yield, is used to determine the price of rice in all markets. In the present study, we show that for every ?1% decrease in chalkiness, an increase of ?1% in head rice yield follows, illustrating the dual impact of chalk on amount of marketable rice and its value. Previous studies in controlled growing conditions report that chalkiness is associated with high temperature. From 1980–2009 at IRRI, Los Baños, the Philippines, annual minimum and mean temperatures, and diurnal variation changed significantly. The objective of this study was to determine how climate impacts chalkiness in field conditions over four wet and dry seasons. We show that low relative humidity and a high vapour pressure deficit in the dry season associate with low chalk and high head rice yield in spite of higher maximum temperature, but in the opposite conditions of the wet season, chalk is high and head rice yield is low. The data therefore suggest that transpirational cooling is a key factor affecting chalkiness and head rice yield, and global warming per se might not be the major factor that decreases the amount and quality of rice, but other climate factors in combination, that enable the crop to maintain a cool canopy.

Zhao, Xiangqian; Fitzgerald, Melissa

2013-01-01

137

Nutritionally enhanced rice to combat malnutrition disorders of the poor.  

PubMed

Major deficiency disorders, including vitamin A deficiency, are especially common in countries in which rice is the staple food. In response to the devastating effects of vitamin A deficiency, which may include blindness and, even death, "Golden Rice" has been developed to deliver this nutrient to those populations who need it most. The case of Golden Rice is used to demonstrate the challenges of radical GMO opposition, consumer acceptance, and regulation of biotechnology-derived foods. PMID:12908739

Potrykus, Ingo

2003-06-01

138

Rice Drying Rates.  

National Technical Information Service (NTIS)

Rice is ordinarily harvested at moisture contents above safe storage levels, so additional drying is usually necessary. The purpose of the research discussed in this report was to determine the factors which affect rice drying rates. The basic approach us...

J. F. Robayo H. B. Pfost

1973-01-01

139

Effects of UV-B and global climate change on rice production: The EPA/IRRI Cooperative Research Plan  

SciTech Connect

The US Environmental Protection Agency and International Rice Research Institute are initiating a cooperative program on the effects of UV-B and global climate change (increased CO{sub 2} and temperature) on rice. Rice is the world's most important food crop and responds both to UV-B and climate change. The project will determine: (1) the effects of these stresses on the rice ecosystem, (2) the extent and intensity of those effects for Asia, (3) the importance of the rice ecosystem as a source of biogenic emissions such as methane and the impacts of environmental stress on those emissions, and (4) mitigation/adaptation options available to reduce any effects on rice yields and biogenic emissions.

Olszyk, D.M.; Ingram, K.T.

1990-01-01

140

Rice Production and Marketing.  

ERIC Educational Resources Information Center

|This guide contains lesson plans for use in secondary programs of agricultural education in geographical areas in which rice is produced. Six units and 13 problem areas are organized into teaching plans that cover the broad nature of rice production. The six units are: (1) determining the importance and history of rice production; (2) determining…

Briers, Gary; Lee, Jasper S.

141

Ethnobotanical investigation of 'wild' food plants used by rice farmers in Kalasin, Northeast Thailand  

PubMed Central

Background Wild food plants are a critical component in the subsistence system of rice farmers in Northeast Thailand. One of the important characteristics of wild plant foods among farming households is that the main collection locations are increasingly from anthropogenic ecosystems such as agricultural areas rather than pristine ecosystems. This paper provides selected results from a study of wild food conducted in several villages in Northeast Thailand. A complete botanical inventory of wild food plants from these communities and surrounding areas is provided including their diversity of growth forms, the different anthropogenic locations were these species grow and the multiplicity of uses they have. Methods Data was collected using focus groups and key informant interviews with women locally recognized as knowledgeable about contemporarily gathered plants. Plant species were identified by local taxonomists. Results A total of 87 wild food plants, belonging to 47 families were reported, mainly trees, herbs (terrestrial and aquatic) and climbers. Rice fields constitute the most important growth location where 70% of the plants are found, followed by secondary woody areas and home gardens. The majority of species (80%) can be found in multiple growth locations, which is partly explained by villagers moving selected species from one place to another and engaging in different degrees of management. Wild food plants have multiple edible parts varying from reproductive structures to vegetative organs. More than two thirds of species are reported as having diverse additional uses and more than half of them are also regarded as medicine. Conclusions This study shows the remarkable importance of anthropogenic areas in providing wild food plants. This is reflected in the great diversity of species found, contributing to the food and nutritional security of rice farmers in Northeast Thailand.

2011-01-01

142

Development of Desiccation Tolerance during Embryogenesis in Rice (Oryza sativa) and Wild Rice (Zizania palustris) (Dehydrin Expression, Abscisic Acid Content, and Sucrose Accumulation).  

PubMed

The ability of seeds to withstand desiccation develops during embryogenesis and differs considerably among species. Paddy rice (Oryza sativa L.) grains readily survive dehydration to as low as 2% water content, whereas North American wild rice (Zizania palustris var interior [Fasset] Dore) grains are not tolerant of water contents below 6% and are sensitive to drying and imbibition conditions. During embryogenesis, dehydrin proteins, abscisic acid (ABA), and saccharides are synthesized, and all have been implicated in the development of desiccation tolerance. We examined the accumulation patterns of dehydrin protein, ABA, and soluble saccharides (sucrose and oligosaccharides) of rice embryos and wild rice axes in relation to the development of desiccation tolerance during embryogenesis. Dehydrin protein was detected immunologically with an antibody raised against a conserved dehydrin amino acid sequence. Both rice and wild rice embryos accumulated a 21-kD dehydrin protein during development, and an immunologically related 38-kD protein accumulated similarly in rice. Dehydrin protein synthesis was detected before desiccation tolerance had developed in both rice embryos and wild rice axes. However, the major accumulation of dehydrin occurred after most seeds of both species had become desiccation tolerant. ABA accumulated in wild rice axes to about twice the amount present in rice embryos. There were no obvious relationships between ABA and the temporal expression patterns of dehydrin protein in either rice or wild rice. Wild rice axes accumulated about twice as much sucrose as rice embryos. Oligosaccharides were present at only about one-tenth of the maximum sucrose concentrations in both rice and wild rice. We conclude that the desiccation sensitivity displayed by wild rice grains is not due to an inability to synthesize dehydrin proteins, ABA, or soluble carbohydrates. PMID:12232094

Still, D. W.; Kovach, D. A.; Bradford, K. J.

1994-02-01

143

Molecular evolution of the rice blast resistance gene Pi-ta in invasive weedy rice in the USA.  

PubMed

The Pi-ta gene in rice has been effectively used to control rice blast disease caused by Magnaporthe oryzae worldwide. Despite a number of studies that reported the Pi-ta gene in domesticated rice and wild species, little is known about how the Pi-ta gene has evolved in US weedy rice, a major weed of rice. To investigate the genome organization of the Pi-ta gene in weedy rice and its relationship to gene flow between cultivated and weedy rice in the US, we analyzed nucleotide sequence variation at the Pi-ta gene and its surrounding 2 Mb region in 156 weedy, domesticated and wild rice relatives. We found that the region at and around the Pi-ta gene shows very low genetic diversity in US weedy rice. The patterns of molecular diversity in weeds are more similar to cultivated rice (indica and aus), which have never been cultivated in the US, rather than the wild rice species, Oryza rufipogon. In addition, the resistant Pi-ta allele (Pi-ta) found in the majority of US weedy rice belongs to the weedy group strawhull awnless (SH), suggesting a single source of origin for Pi-ta. Weeds with Pi-ta were resistant to two M. oryzae races, IC17 and IB49, except for three accessions, suggesting that component(s) required for the Pi-ta mediated resistance may be missing in these accessions. Signatures of flanking sequences of the Pi-ta gene and SSR markers on chromosome 12 suggest that the susceptible pi-ta allele (pi-ta), not Pi-ta, has been introgressed from cultivated to weedy rice by out-crossing. PMID:22043312

Lee, Seonghee; Jia, Yulin; Jia, Melissa; Gealy, David R; Olsen, Kenneth M; Caicedo, Ana L

2011-10-17

144

Molecular Evolution of the Rice Blast Resistance Gene Pi-ta in Invasive Weedy Rice in the USA  

PubMed Central

The Pi-ta gene in rice has been effectively used to control rice blast disease caused by Magnaporthe oryzae worldwide. Despite a number of studies that reported the Pi-ta gene in domesticated rice and wild species, little is known about how the Pi-ta gene has evolved in US weedy rice, a major weed of rice. To investigate the genome organization of the Pi-ta gene in weedy rice and its relationship to gene flow between cultivated and weedy rice in the US, we analyzed nucleotide sequence variation at the Pi-ta gene and its surrounding 2 Mb region in 156 weedy, domesticated and wild rice relatives. We found that the region at and around the Pi-ta gene shows very low genetic diversity in US weedy rice. The patterns of molecular diversity in weeds are more similar to cultivated rice (indica and aus), which have never been cultivated in the US, rather than the wild rice species, Oryza rufipogon. In addition, the resistant Pi-ta allele (Pi-ta) found in the majority of US weedy rice belongs to the weedy group strawhull awnless (SH), suggesting a single source of origin for Pi-ta. Weeds with Pi-ta were resistant to two M. oryzae races, IC17 and IB49, except for three accessions, suggesting that component(s) required for the Pi-ta mediated resistance may be missing in these accessions. Signatures of flanking sequences of the Pi-ta gene and SSR markers on chromosome 12 suggest that the susceptible pi-ta allele (pi-ta), not Pi-ta, has been introgressed from cultivated to weedy rice by out-crossing.

Lee, Seonghee; Jia, Yulin; Jia, Melissa; Gealy, David R.; Olsen, Kenneth M.; Caicedo, Ana L.

2011-01-01

145

Modelling the impacts of climate change and methane emission reductions on rice production: a review  

Microsoft Academic Search

Rice agriculture is not only affected by climate change, but also contributes to global warming through the release of methane into the atmosphere. In 1989, a major research project was initiated at the International Rice Research Institute in the Philippines to investigate relationships between climate change and rice production. A second project started in 1993 to investigate, in more detail,

Robin Matthews; Reiner Wassmann

2003-01-01

146

Speciation And Distribution Of Arsenic And Localization Of Nutrients In Rice Grains  

EPA Science Inventory

Arsenic (As) contamination of rice grains and the generally low concentration of micronutrients in rice have been recognized as a major concern for human health. Here, we investigated the speciation and localization of As and the distribution of (micro)nutrients in rice grains b...

147

Development of drought-resistant cultivars using physiomorphological traits in rice  

Microsoft Academic Search

Drought is a major problem for rice grown under rainfed lowland and upland conditions, but progress in breeding to improve drought resistance has been slow. This paper describes patterns of water-stress development in rice fields, reviews genetic variation in physio-morphological traits for drought resistance in rice, and suggests how knowledge of stress physiology can contribute to plant breeding programmes that

S. Fukai; M. Cooper

1995-01-01

148

Genetic Variation at the waxy locus associated with starch pasting properties in international rice germplasm  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rice starch pasting properties are used to characterize the processing and cooking qualities of rice (Oryza sativa L.). The Waxy gene on rice chromosome 6 encodes the granule-bound starch synthase enzyme, which controls much of the variation in grain amylose content, and reportedly has major effects...

149

SOME EFFECTS OF RICE QUALITY ON ROUGH RICE PRICES  

Microsoft Academic Search

ance markets on the western side of the Texas Quality discounts and premiums for rough Rice Belt (i.e., west of Houston). Previous rice in Texas rice bid\\/acceptance markets are research has indicated significant price dis- analyzed. The most important quality factors counts in Texas being associated with various determining the value of rough rice are head rice pests, including stinkbugs,

B. Wade Brorsen; M. Edward Rister

1988-01-01

150

Insect pest management in tropical Asian irrigated rice.  

PubMed

Abundant natural enemies in tropical Asian irrigated rice usually prevent significant insect pest problems. Integrated pest management (IPM) extension education of depth and quality is required to discourage unnecessary insecticide use that upsets this natural balance, and to empower farmers as expert managers of a healthy paddy ecosystem. Farmers' skill and collaboration will be particularly important for sustainable exploitation of the potential of new, higher-yielding and pest-resistant rice. IPM "technology transfer" through training and visit (T&V) extension systems failed, although mass media campaigns encouraging farmer participatory research can reduce insecticide use. The "farmer first" approach of participatory nonformal education in farmer field schools, followed by community IPM activities emphasizing farmer-training-farmer and research by farmers, has had greater success in achieving IPM implementation. Extension challenges are a key topic for rice IPM research, and new pest management technology must promote, rather than endanger, ecological balance in rice paddies. PMID:10761589

Matteson, P C

2000-01-01

151

Rice Trade Policies and Their Implications for Food Security  

Microsoft Academic Search

There is a strong linkage between the behavior of the rice market and the state of food security in many regions around the world, particularly in Asia, as made evident in the 2007-08 commodity crisis. Rice is a staple for the majority of the population in Asia, where roughly 60% of the close to one billion undernourished people live (FAO,

Alvaro Durand-Morat; Eric J. Wailes

2011-01-01

152

SIRBINT A NEW SIMULATION MODEL TO FORECAST RICE BLAST DISEASE  

Microsoft Academic Search

Abstract Pyricularia grisea (Cooke) Sacc. is the causal organism of blast, the most serious disease of rice because of its devastating nature, widespread distribution and existence of several physiologic races. It occurs in epiphytotic conditions in all major rice-growing regions of the world, as well asin Italy. Nowadays, no strategies in current use are based on the dynamics of airborne

Massimo Biloni; Marinella Rodolfi; Anna Maria Picco

153

Rice protein-based infant formula: current status and future development.  

PubMed

Rice is the world's leading staple cereal food and is the major source of protein for many parts of the world. Rice is among the first solid foods fed to infants in many cultures, in part because of its hypoallergenicity from lack of gluten. Nutritional quality of rice protein compares favorably with other cereal proteins including wheat, oat and barley. It is rich in methionine and cystine, although as is the case for other cereals, it is an incomplete protein source for human infants with lysine and threonine being the primary limiting amino acids. Fortification of rice proteins with these two limiting amino acids improves its protein quality. Rice protein-based infant formulas (RPF) were initially based on high protein rice flours, but more recently are based on rice protein concentrates, isolates or hydrolysates, fortified with lysine and threonine. Hypoallergenicity efficacy, particularly for hydrolyzed rice protein-based formulas, has been reported, and limited data indicated that rice protein based infant formula may provide potentially adequate alternative if standard milk- or soy protein-based formulas are not tolerated. Unlike the rice-protein based infant formula, rice beverage formulas made from rice flour are nutritionally inadequate for infants. Reports have indicated stunted growth in infants/children fed rice beverage formulas. Future development for the RPF include those based on genetically improved rice with high lysine and threonine content, supplementation with appropriate mineral and fat blend, and long-term clinical studies in infants to confirm its efficacy and safety. PMID:17301723

Koo, W W K; Lasekan, J B

2007-02-01

154

Genetic, Physiological, and Gene Expression Analyses Reveal That Multiple QTL Enhance Yield of Rice Mega-Variety IR64 under Drought  

PubMed Central

Background Rice (Oryza sativa L.) is a highly drought sensitive crop, and most semi dwarf rice varieties suffer severe yield losses from reproductive stage drought stress. The genetic complexity of drought tolerance has deterred the identification of agronomically relevant quantitative trait loci (QTL) that can be deployed to improve rice yield under drought in rice. Convergent evidence from physiological characterization, genetic mapping, and multi-location field evaluation was used to address this challenge. Methodology/Principal Findings Two pairs of backcross inbred lines (BILs) from a cross between drought-tolerant donor Aday Sel and high-yielding but drought-susceptible rice variety IR64 were produced. From six BC4F3 mapping populations produced by crossing the +QTL BILs with the ?QTL BILs and IR64, four major-effect QTL - one each on chromosomes 2, 4, 9, and 10 - were identified. Meta-analysis of transcriptome data from the +QTL/?QTL BILs identified differentially expressed genes (DEGs) significantly associated with QTL on chromosomes 2, 4, 9, and 10. Physiological characterization of BILs showed increased water uptake ability under drought. The enrichment of DEGs associated with root traits points to differential regulation of root development and function as contributing to drought tolerance in these BILs. BC4F3-derived lines with the QTL conferred yield advantages of 528 to 1875 kg ha?1 over IR64 under reproductive-stage drought stress in the targeted ecosystems of South Asia. Conclusions/Significance Given the importance of rice in daily food consumption and the popularity of IR64, the BC4F3 lines with multiple QTL could provide higher livelihood security to farmers in drought-prone environments. Candidate genes were shortlisted for further characterization to confirm their role in drought tolerance. Differential yield advantages of different combinations of the four QTL reported here indicate that future research should include optimizing QTL combinations in different genetic backgrounds to maximize yield advantage under drought.

Swamy B. P., Mallikarjuna; Ahmed, Helal Uddin; Henry, Amelia; Mauleon, Ramil; Dixit, Shalabh; Vikram, Prashant; Tilatto, Ram; Verulkar, Satish B.; Perraju, Puvvada; Mandal, Nimai P.; Variar, Mukund; S., Robin; Chandrababu, Ranganath; Singh, Onkar N.; Dwivedi, Jawaharlal L.; Das, Sankar Prasad; Mishra, Krishna K.; Yadaw, Ram B.; Aditya, Tamal Lata; Karmakar, Biswajit; Satoh, Kouji; Moumeni, Ali; Kikuchi, Shoshi; Leung, Hei; Kumar, Arvind

2013-01-01

155

[Advance on the cloning and functional analysis of disease resistance genes in rice].  

PubMed

Improving the disease resistance of rice is a major objective in rice breeding programs, which provides a basic guarantee for the good quality and high yield in rice. Recently, substantial progresses on the research of rice disease resistant mechanism had been made. Some important genes had been identified and cloned. The recent achievements in identification, cloning, and biological function analyses of these genes were summarized and their potential application in breeding was also discussed. PMID:19840921

E, Zhi-Guo; Wang, Lei

2009-10-01

156

Rice that Filipinos Grow and Eat  

Microsoft Academic Search

This paper introduces rice to the reader and analyzes the changes it has gone through these past 100 years in the shaping hands of varietal improvement science. Here, the richness of the crop as a genetic material and resource is revealed. Landrace rice, pureline selection rice, crossbred rice, semidwarf rice, hybrid rice, new plant type rice, designer rice - from

John C. de Leon

2005-01-01

157

Chesapeake Bay: Introduction to an Ecosystem.  

ERIC Educational Resources Information Center

|The Chesapeake Bay is the largest estuary in the contiguous United States. The Bay and its tidal tributaries make up the Chesapeake Bay ecosystem. This document, which focuses of various aspects of this ecosystem, is divided into four major parts. The first part traces the geologic history of the Bay, describes the overall physical structure of…

Environmental Protection Agency, Washington, DC.

158

PRESERVING BIODIVERSITY: SPECIES, ECOSYSTEMS, OR LANDSCAPES?  

Microsoft Academic Search

Efforts to preserve biological diversity must focus increasingly at the ecosystem level because of the immense number of species, the majority of which are currently unknown. An ecosystem approach is also the only way to conserve processes and habitats (such as forest canopies, belowground habitats, and hyporheic zones) that, with their constituent species, are poorly known. Continued concern with species

JERRY F. FRANKLIN

1993-01-01

159

ESRP approach to using final ecosystem services  

EPA Science Inventory

The U.S. Environmental Protection Agency has developed the ecosystem Services Research Program (ESRP) as one of its major research efforts. The goal of this program is to create â??A comprehensive theory and practice for quantifying ecosystem services so that their value and their...

160

Perceptions about varieties of brown rice: a qualitative study from Southern India.  

PubMed

Consumption of whole grains, such as brown rice, compared to white rice can decrease the risk of type 2 diabetes mellitus. This qualitative study conducted in 2009 sought to identify factors that can act as barriers to or promote acceptance of brown rice as a staple food among South Indian adults (n=65). Using purposeful sampling, eight focus groups were conducted among adults with normal body mass index and adults who were overweight, aged 24 to 47 years, living in slum and non-slum sites in Chennai, a city in Southern India. These focus groups, conducted in Tamil, the local language of Chennai, were homogenous by sex. The focus groups were audiotaped after obtaining consent. Results were transcribed and coded according to four major themes that emerged during the focus group discussions, including culture and dietary practices, factors influencing rice preferences, awareness and perceptions of brown rice, and barriers to and factors influencing acceptance of brown rice. Overall, the majority of participants favored eating rice and rice-based foods. Tradition largely dictated the specific form of rice that people consumed. Awareness about the nutritive properties of brown rice was poor and was cited as a major barrier to its acceptance. In addition, participants tended to consider cooked rice that was neither white nor long-grained to be inferior. However, they believed that although convincing people to switch to brown rice would be a slow process, promoting its healthful benefits could serve to popularize it. PMID:21963018

Kumar, Shuba; Mohanraj, Rani; Sudha, Vasudevan; Wedick, Nicole M; Malik, Vasanti; Hu, Frank B; Spiegelman, Donna; Mohan, Viswanathan

2011-10-01

161

Population diversity and ecosystem services  

Microsoft Academic Search

The current rate of biodiversity loss threatens to disrupt greatly the functioning of ecosystems, with potentially significant consequences for humanity. The magnitude of the loss is generally measured with the use of species extinction rates, an approach that understates the severity of the problem and masks some of its most important consequences. Here, we propose a major expansion of this

Gary W. Luck; Gretchen C. Daily; Paul R. Ehrlich

2003-01-01

162

Carbon sequestration and methane emission from a tropical rice field under intensive rice cultivation with long-term application of compost and inorganic fertilizer  

Microsoft Academic Search

The impact of long-term intensive rice-rice cropping system with different managements on soil organic carbon content (SOC) and methane emission was studied using a 36-year-old fertility experiment under tropical climate. Intensive rice production systems are important sinks of carbon but at the same time these are the major anthropogenic sources of atmospheric CH4, a major greenhouse gas. A significant increase

D. R. Nayak; J. Yeluriapti; T. K. Adhya

2009-01-01

163

40 CFR Table 1a to Subpart Zzzz of... - Emission Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE...  

Code of Federal Regulations, 2011 CFR

...Reconstructed Spark Ignition, 4SRB Stationary RICE > 500 HP Located at a Major Source of HAP...Reconstructed Spark Ignition, 4SRB Stationary RICE > 500 HP Located at a Major Source of HAP...new and reconstructed 4SRB stationary RICE >500 HP located at a major source of...

2011-07-01

164

Internet Geography: Ecosystems  

NSDL National Science Digital Library

This site about ecosystems and biomes contains a map of different ecosystems, and provides rainfall statistics for each biome. There are sections on tropical rainforest, taiga (or boreal forest), savanna, desert, and tundra ecosystems. Each section describes the biome and its origins, where it is found, and how humans impact it. In some cases, sustainable development of the ecosystem is explained.

165

The use of rice seeds to produce human pharmaceuticals for oral therapy.  

PubMed

Rice (Oryza sativa L.) is the major staple food consumed by half of the world's population. Rice seeds have gained recent attention as bioreactors for the production of human pharmaceuticals such as therapeutic proteins or peptides. Rice seed production platforms have many advantages over animal cell or microbe systems in terms of cost-effectiveness, scalability, safety, product stability and productivity. Rice seed-based human pharmaceuticals are expected to become innovative therapies as edible drugs. Therapeutic proteins can be sequestered within natural cellular compartments in rice seeds and protected from harsh gastrointestinal environments. This review presents the state-of-the-art on the construction of gene cassettes for accumulation of pharmaceutical proteins or peptides in rice seeds, the generation of transgenic rice plants, and challenges involved in the use of rice seeds to produce human pharmaceuticals. PMID:24092672

Wakasa, Yuhya; Takaiwa, Fumio

2013-09-17

166

Characterization of peptides generated in proteolytic digest of steamed rice grains by sake koji enzymes.  

PubMed

High-molecular-weight peptides (approximately 10-30 kDa) generated in a digest of steamed rice grains by sake koji enzymes were characterized. Among 13 major spots resolved by 2-D gel electrophoresis, 12 contained peptides having N-termini of rice glutelin as determined by mass fingerprinting analysis and/or MS/MS. The source of these peptides was presumed to be the acidic subunit of rice glutelin. An addition of up to 25% glucose in the digestion of an isolated rice protein body induced the accumulation of these peptides. The level of accumulation of these peptides in the digest of 70% polished rice samples correlated well with the crude protein content of the rice grains. The degree of accumulation of these peptides in Yamadanishiki and low-polish-rate rice was low, whereas that observed in 90% polished rice samples was extremely low. PMID:18023795

Hashizume, Katsumi; Okuda, Masaki; Numata, Mineyo; Zhou, Yan; Koseki, Takuya

2007-10-01

167

Mycotoxins in rice  

Microsoft Academic Search

Mycotoxin contamination in rice is usually lower as in wheat or corn. However, there are some reports that rice has been contaminated with mycotoxins such as aflatoxin B1, B2, G1, G2 (AFS), citrinin, deoxynivalenol (DON), fumonisin B1, B2, B3 (FMS), fusarenon-X (Fus.-X), nivalenol (NIV), ochratoxin A (OTA), sterigmatocystin (STE), and zearalenone. Rice in Japan is preserved in warehouses where moisture

Kenji Tanaka; Yuki Sago; Yazhi Zheng; Hiroyuki Nakagawa; Masayo Kushiro

2007-01-01

168

A selectively terminable transgenic rice line expressing human lactoferrin.  

PubMed

Human lactoferrin (hLF) is a multifunctional milk protein which could be utilized for promoting human health. Transgenic rice has been used as a bioreactor for mass production of recombinant hLF. However, one major concern over such transgenic rice is the risk of its unintended spreading into environment and into our food supplies. Here we report the development of selectively terminable transgenic rice expressing human lactoferrin in seeds. These transgenic rice plants could be selectively terminated by bentazon, a common herbicide used for rice weed control. The hLF expression cassette was constructed into a T-DNA containing the RNA interference cassette suppressing the expression of the rice gene CYP81A6 which detoxifies herbicide bentazon, and the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) cassette which confers to glyphosate tolerance. A transgenic line, named as G281, was identified for its high sensitivity to bentazon, high tolerance to glyphosate, and high expression of hLF. Southern analysis suggested G281 is a single copy insertion event. Field tests demonstrated that G281 plants can be completely killed by a single spray of bentazon at 1000 mg/L, which is safe to regular rice and represents only half of the dose recommended by manufacturer for rice field weed control. Therefore, any G281 contaminations in regular rice could be selectively terminated to make sure it will not enter food or feed supplies. PMID:20433928

Lin, Chaoyang; Nie, Peng; Lu, Wei; Zhang, Qing; Li, Jing; Shen, Zhicheng

2010-04-28

169

Modelling the Security Ecosystem - The Dynamics of (In)Security  

Microsoft Academic Search

by a wide variety of actors and pro- cesses which together make up a security ecosystem; here we examine this ecosystem, consolidating many as- pects of security that have hitherto been discussed only separately. First, we analyze the roles of the major ac- tors within this ecosystem and the processes they par- ticipate in, and the the paths vulnerability data

Stefan Frei; Dominik Schatzmann; Bernhard Plattner; Brian Trammell

170

Ecosystem type affects interpretation of soil nematode community measures  

Microsoft Academic Search

A better understanding of performance among major ecosystem types is necessary before nematode community indices can be applied at large geographic scales, ranging from regional to global. The objectives of this study were to: (1) determine the inherent variability in soil properties among and within wetland, forest and agricultural ecosystems; (2) compare nematode community composition among and within ecosystem types

D. A. Neher; J. Wub; M. E. Barbercheck; O. Anas

2005-01-01

171

Whole-Ecosystem Experiments: Replication Versus Realism: The Need for Ecosystem-Scale Experiments  

Microsoft Academic Search

The results of bottle and mesocosm experiments were compared with those obtained in whole-ecosystem experiments at the Experimental\\u000a Lakes Area. Unless they can be cleverly designed to mimic major ecosystem processes and community compositions, smaller-scale\\u000a experiments often give highly replicable, but spurious, answers. Problems with appropriate scaling are difficult to deduce\\u000a without direct comparisons with whole-ecosystem experiments. Reasons are many,

David W. Schindler

1998-01-01

172

Managing Marine Ecosystems and Development: Experiences from the Chesapeake Bay and Other Coastal Ecosystems in the United States  

Microsoft Academic Search

In order to maintain the biotic integrity and performance of coastal marine ecosystems affected by human population growth and economic development an ecosystem approach to management is required. This is par- ticularly challenging when, as is the case for many coastal ecosystems, development activities on land, often far removed from the coast, have a major impact on the coastal environment.

Donald F. Boesch

173

Toward a Cytological Characterization of the Rice Genome  

PubMed Central

Rice (Oryza sativa L.) will be the first major crop, as well as the first monocot plant species, to be completely sequenced. Integration of DNA sequence-based maps with cytological maps will be essential to fully characterize the rice genome. We have isolated a set of 24 chromosomal arm-specific bacterial artificial chromosomes to facilitate rice chromosome identification. A standardized rice karyotype was constructed using meiotic pachytene chromosomes of O. sativa spp. japonica rice var. Nipponbare. This karyotype is anchored by centromere-specific and chromosomal arm-specific cytological landmarks and is fully integrated with the most saturated rice genetic linkage maps in which Nipponbare was used as one of the mapping parents. An ideogram depicting the distribution of heterochromatin in the rice genome was developed based on the patterns of 4',6-diamidino-2-phenylindole staining of the Nipponbare pachytene chromosomes. The majority of the heterochromatin is distributed in the pericentric regions with some rice chromosomes containing a significantly higher proportion of heterochromatin than other chromosomes. We showed that pachytene chromosome-based fluorescence in situ hybridization analysis is the most effective approach to integrate DNA sequences with euchromatic and heterochromatic features.

Cheng, Zhukuan; Buell, C. Robin; Wing, Rod A.; Gu, Minghong; Jiang, Jiming

2001-01-01

174

Rice Cluster I, an Important Group of Archaea Producing Methane in Rice Fields  

NASA Astrophysics Data System (ADS)

Rice fields are an important source for the greenhouse gas methane. Methane is a major degradation product of organic matter in the anoxic soil, is partially oxidized in the rhizosphere and is emitted into the atmosphere through the aerenchyma system of the plants. Anaerobic degradation of organic matter by fermenting bacteria eventually results in the production of acetate and hydrogen, the two major substrates for microbial methanogenesis. The community of methanogenic archaea consists of several major orders or families including hydrogen-utilizing Rice Cluster-I (RC-I). Environmental conditions affect the methanogenic degradation process and the community structure of the methanogenic archaea in soil and rhizosphere. For example, populations of acetoclastic Methanosaetaceae and Methanosarcinaceae are enhanced by low and high acetate concentrations, respectively. Stable isotope probing of 16S rRNA showed that RC-I methanogens are mainly active on rice roots and at low H2 concentrations. Growth and population size is largely consistent with energetic conditions. RC-I methanogens on roots seem to be responsible for methane production from plant photosynthates that account for a major part of the emitted methane. Populations of RC-I methanogens in rice field soil are also enhanced at elevated temperatures (40-50°C). Moderately thermophilic members of RC-I methanogens or other methanogenic families were found to be ubiquitously present in soils from rice fields and river marshes. The genome of a RC-I methanogen was completely sequenced out of an enrichment culture using a metagenome approach. Genes found are consistent with life in the rhizosphere and in temporarily drained, oxic soil. We found that the methanogenic community structure on the rice roots is mainly determined by the respective community structure of the soil, but is in addition affected by the rice cultivar. Rice microcosms in which soil and rice roots are mainly colonized by RC-I methanogens produce and emit more methane than when inhabited by Methanomicrobiales, indicating that the methanogenic archaeal community is an important factor for methane emission from rice fields.

Conrad, R.

2006-12-01

175

The Evolution of Rice Production Practices  

Microsoft Academic Search

In this chapter, a summary of the evolution of major practices in rice production over the last 100 years in the country is presented. These practices essentially evolved out of the changes in the varieties introduced and planted by Filipino farmers, which have to change the manner by which production and postharvest operations have to be done in order to

Eulito U. Bautista; Evelyn F. Javier

2005-01-01

176

Project RICE (Responsive Inner City Education).  

ERIC Educational Resources Information Center

Project RICE (Responsive Inner City Education) prepared a cadre of 36 teachers drawn from majority and minority populations in 3 inner-city schools in Buffalo (New York) to complement mastery of subject matter with appropriate pedagogical styles. The project was designed to test the hypothesis that minority students in inner-city schools do not…

Mattai, P. Rudy

177

Isozymes and classification of Asian rice varieties  

Microsoft Academic Search

Enzyme variation detected by starch gel electrophoresis was used to investigate the genetic structure of Oryza sativa L. species. Fifteen polymorphic loci coding for 8 enzymes were surveyed among 1688 traditional rices from Asia. Multivariate analysis of the data resulted in identification of six varietal groups, with two major ones, groups I and VI, two minor ones, groups II and

J. C. Glaszmann

1987-01-01

178

Golden Rice - the Partitioning of Influence  

Microsoft Academic Search

In the past decade significant scientific progress has been made with the Golden Rice project. Significant increases in carotenoid have been achieved. Micronutrient malnutrition has been recognised as a major factor in total world malnutrition. What could be responsible for the continuing slow progress of the project? The answer may be related to the confluence of three influences on world

Adrian C Dubock

179

Rice Outlook, March 2008.  

National Technical Information Service (NTIS)

U.S. and global rice prices continue to soar. The February mid-month U.S. rough-rice cash price was reported at $12.20 per cwt, up 40 cents from January and the highest since July 1981. Prices have risen every month since September. This month, the 2007/0...

N. Childs

2008-01-01

180

Registration of 'Cybonnet' Rice  

Technology Transfer Automated Retrieval System (TEKTRAN)

‘Cybonnet’ rice is a high-yielding, short-season, long-grain cultivar. It originated form the cross ‘Cypress’//’Newbonnet’/’Katy’ made at the University of Arkansas Rice Research and Extension Center in Stuttgart, AR. Cybonnet is similar in maturity to ‘Kaybonnet’ and ‘Wells’, is a simidwarf culti...

181

Rice - A Nutraceutical  

Microsoft Academic Search

Rice is known as the grain of life, and is synonymous with food for Asians. In addition to being a staple food and an integral part of social rites, rituals, and festivals in almost all Asian countries, it has a medicinal value too, which was clearly recognized by the medicine systems of the region centuries ago. Rice is the main

Uma Ahuja; SC Ahuja; Rashmi Thakrar; RK Singh

2008-01-01

182

Kernel elongation in rice.  

PubMed

Kernel elongation after cooking is an important character of fine rice and most rice consumers prefer length-wise elongation. Although improvement of aromatic rice began early in the 1970s, until now the mechanisms and genetics of kernel elongation has remained unrevealed. Kernel elongation is considered as a physical phenomenon and is influenced by several physicochemical and genetic factors, including genotypes, aging temperature, aging time, water uptake, amylose content and gelatinization temperature. Recently the complete genetic map of fine rice has been created and the gene responsible for kernel length identified; moreover, this gene is tightly linked with the cooked kernel elongation trait. Several molecular markers linked with cooked kernel elongation have been developed. These tools will be helpful for the improvement of this important trait. For the proper study of cooked kernel elongation of rice, this review paper will provide the basis and directional materials for further studies. PMID:23238771

Golam, Faruq; Prodhan, Zakaria H

2012-12-12

183

The LANSCE RICE Control System Upgrade.  

SciTech Connect

The LANSCE (Los Alamos Neutron Science Center) control system upgrade program continues with the impending replacement of the RICE (Remote Instrumentation and Control Equipment) subsystem. The RICE subsystem upgrade is a challenge because of its technology (late 1960’s), number of channels (>10,000), and unique characteristics (all-modules data takes, timed/flavored data takes). The plan is to replace at least the non-timed data and the command portions of the subsystem with Programmable Logic Controllers (PLCs). We discuss motivations, technological challenges, proofof- principle, and planning. The boundary condition, as usual, is that we must implement these major changes on a running accelerator.

Oothoudt, Michael; Bjorklund, Eric; Burns, Mary; Carr, Gary; Faucett, John; Hayden, David; Lusk, Matthew; Merl, Robert; Potter, Jerry; Reynolds, Jerome; Romero, Dolores

2003-04-24

184

The importance of maintenance breeding: A case study of the first miracle rice variety-IR8  

Microsoft Academic Search

The green revolution was initiated by introduction of modern high yielding rice and wheat varieties in the 1960s. In recent years, however, there are signs of stagnating yields in major rice producing areas of Asia, which suggests a lack of genetic gain in yield potential in rice improvement program. We examined the grain yield of IR8, which was the first

Shaobing Peng; Jianliang Huang; Kenneth G. Cassman; Rebecca C. Laza; Romeo M. Visperas; Gurdev S. Khush

2010-01-01

185

Comparing rice production systems: A challenge for agronomic research and for the dissemination of knowledge-intensive farming practices  

Microsoft Academic Search

This article is a commentary on several research studies conducted on the prospects for aerobic rice production systems that aim at reducing the demand for irrigation water which in certain major rice producing areas of the world is becoming increasingly scarce. The research studies considered, as reported in published articles mainly under the aegis of the International Rice Research Institute

Willem A. Stoop; Abdoulaye Adam; Amir Kassam

2009-01-01

186

Monitoring rice cropping systems using China environment satellite data in Poyang Lake region  

NASA Astrophysics Data System (ADS)

Threshold method was utilized to discriminate rice cropping systems based on the noticeable variation of Normalized Difference Vegetation Index (NDVI) during key growth stages in Poyang Lake Region, China. This area is dominated by double- and single rice cropping systems which tend to change due to the frequent ecosystem management policies. We used a new satellite data from the CCD camera sensor with 30 m spatial resolution onboard the China Environmental Satellite HJ-1A and B. The HJ -1A/B with a better temporal resolution of four days provides more data options for effective and timely agriculture monitoring. The result showed that there is evident difference of NDVI between single and late rice during mid October when they are in different growth stages. The areas of single and late rice in 2011 were 2988.6 km2 and 3105.9 km2, respectively. Paddy field distribution map and local paddy rice calendar are requisite to move the threshold method into other multiple rice cropping regions. The study suggests that the China Environmental Satellite HJ-1A/B have the potential to rice cropping system in the double to triple rice cropping systems area. With many advantages of HJ-1A/B, like, finer spatial and temporal resolution, bigger imaging swath, it may make rice cropping system monitoring more feasible and operational.

Li, Peng; Jiang, Luguang; Feng, Zhiming

187

Effect of rice cultivation systems on indigenous arbuscular mycorrhizal fungal community structure.  

PubMed

Arbuscular mycorrhizal fungi (AMF) in an agricultural ecosystem are necessary for proper management of beneficial symbiosis. Here we explored how the patterns of the AMF community in rice roots were affected by rice cultivation systems (the system of rice intensification [SRI] and the conventional rice cultivation system [CS]), and by compost application during growth stages. Rice plants harvested from SRI-managed plots exhibited considerably higher total biomass, root dry weight, and seed fill than those obtained from conventionally managed plots. Our findings revealed that all AMF sequences observed from CS plots belonged (only) to the genus Glomus, colonizing in rice roots grown under this type of cultivation, while rice roots sown in SRI showed sequences belonging to both Glomus and Acaulospora. The AMF community was compared between the different cultivation types (CS and SRI) and compost applications by principle component analysis. In all rice growth stages, AMF assemblages of CS management were not separated from those of SRI management. The distribution of AMF community composition based on T-RFLP data showed that the AMF community structure was different among four cultivation systems, and there was a gradual increase of Shannon-Weaver indices of diversity (H') of the AMF community under SRI during growth stages. The results of this research indicated that rice grown in SRI-managed plots had more diverse AMF communities than those grown in CS plots. PMID:23719585

Watanarojanaporn, Nantida; Boonkerd, Nantakorn; Tittabutr, Panlada; Longtonglang, Aphakorn; Young, J Peter W; Teaumroong, Neung

2013-05-29

188

Methylated arsenic species in rice: geographical variation, origin, and uptake mechanisms.  

PubMed

Rice is a major source of inorganic arsenic (iAs) in the human diet because paddy rice is efficient at accumulating As. Rice As speciation is dominated by iAs and dimethylarsinic acid (DMA). Here we review the global pattern in rice As speciation and the factors causing the variation. Rice produced in Asia shows a strong linear relationship between iAs and total As concentration with a slope of 0.78. Rice produced in Europe and the United States shows a more variable, but generally hyperbolic relationship with DMA being predominant in U.S. rice. Although there is significant genotypic variation in grain As speciation, the regional variations are primarily attributed to environmental factors. Emerging evidence also indicates that methylated As species in rice are derived from the soil, while rice plants lack the As methylation ability. Soil flooding and additions of organic matter increase microbial methylation of As, although the microbial community responsible for methylation is poorly understood. Compared with iAs, methylated As species are taken up by rice roots less efficiently but are transported to the grain much more efficiently, which may be an important factor responsible for the spikelet sterility disorder (straight-head disease) in rice. DMA is a weak carcinogen, but the level of ingestion from rice consumption is much lower than that of concern. Questions that require further investigations are identified. PMID:23521218

Zhao, Fang-Jie; Zhu, Yong-Guan; Meharg, Andrew A

2013-04-10

189

Effects of arsenic compound amendment on arsenic speciation in rice grain.  

PubMed

Rice consumption is a major source of arsenic for Asian populations. Arsenic is present in rice grain both as inorganic arsenic and as dimethylarsinic acid (DMA). It is unclear whether DMA in rice is taken up from the soil or synthesized in planta. We investigated the effect of DMA, methylarsonic acid (MMA) and arsenite amendment on arsenic speciation in rice grain grown in soil and in solution culture. We also investigated the methylation of arsenic in solution culture under suppression of bacterial activity. When rice was grown under flooded conditions after the heading stage, DMA amendment to the soil resulted in higher DMA concentration in brown rice and rice straw. In the solution culture, not only DMA amendment but also MMA or arsenite amendment increased the DMA concentration in brown rice and rice straw. DMA was detected in the solution amended by MMA or arsenite with young rice plants. When the solution included the antibacterial agent chloramphenicol, DMA concentration in the solution decreased dramatically. When only the soil was incubated with MMA or arsenite, only a slight amount of DMA was detected in the soil. These results suggest that rice rhizosphere associated bacteria would be involved in the formation of DMA in brown rice. PMID:21247103

Arao, Tomohito; Kawasaki, Akira; Baba, Koji; Matsumoto, Shingo

2011-01-19

190

Climate change: implications for the yield of edible rice.  

PubMed

Global warming affects not only rice yield but also grain quality. A better understanding of the effects of climate factors on rice quality provides information for new breeding strategies to develop varieties of rice adapted to a changing world. Chalkiness is a key trait of physical quality, and along with head rice yield, is used to determine the price of rice in all markets. In the present study, we show that for every ?1% decrease in chalkiness, an increase of ?1% in head rice yield follows, illustrating the dual impact of chalk on amount of marketable rice and its value. Previous studies in controlled growing conditions report that chalkiness is associated with high temperature. From 1980-2009 at IRRI, Los Baños, the Philippines, annual minimum and mean temperatures, and diurnal variation changed significantly. The objective of this study was to determine how climate impacts chalkiness in field conditions over four wet and dry seasons. We show that low relative humidity and a high vapour pressure deficit in the dry season associate with low chalk and high head rice yield in spite of higher maximum temperature, but in the opposite conditions of the wet season, chalk is high and head rice yield is low. The data therefore suggest that transpirational cooling is a key factor affecting chalkiness and head rice yield, and global warming per se might not be the major factor that decreases the amount and quality of rice, but other climate factors in combination, that enable the crop to maintain a cool canopy. PMID:23776635

Zhao, Xiangqian; Fitzgerald, Melissa

2013-06-12

191

Mycotoxins in rice.  

PubMed

Mycotoxin contamination in rice is usually lower as in wheat or corn. However, there are some reports that rice has been contaminated with mycotoxins such as aflatoxin B1, B2, G1, G2 (AFS), citrinin, deoxynivalenol (DON), fumonisin B1, B2, B3 (FMS), fusarenon-X (Fus.-X), nivalenol (NIV), ochratoxin A (OTA), sterigmatocystin (STE), and zearalenone. Rice in Japan is preserved in warehouses where moisture content and temperature are regulated. Therefore, mycotoxin contamination from post harvest fungal growth occurs very seldom. Trichothecenes, aflatoxins, and STE in rice were recently analyzed in our laboratory. In 1998, a typhoon struck before rice harvesting in Japan, and the unpolished rice was found to be stained brown. Samples were collected and analyzed for the presence of trichothecenes. Mycotoxins DON, Fus.-X, and NIV were detected and confirmed with GC-MS. The quantity of trichothecenes was determined using GC-ECD. STE is a carcinogenic mycotoxin produced by Aspergillus versicolor and some other fungi. STE contamination of rice was studied in our laboratory since 1973. GC-MS, LC-MS, LC-MS/MS, and LC-UV methods for STE determination were examined, giving good results for the LC-UV method using a photo diode array detector. Different techniques for the extraction of STE from rice were also studied. Finally, brown rice was ground, and the ground rice was extracted with acetonitrile-water. An Autoprep MF-A 1000 column was used to clean up AFS and STE. The cleaned-up extract was analyzed with HPLC-UV. Forty-eight brown rice samples were analyzed, and none of them were contaminated with STE. These rice samples were also analyzed for AFS and FMS, and none of the samples were contaminated. The Ministry of Agriculture, Forestry and Fisheries in Japan is making the appropriate Institutes develop analytical methods for mycotoxins and survey mycotoxin contamination on rice as well as wheat, corn, and some other cereals. PMID:17913273

Tanaka, Kenji; Sago, Yuki; Zheng, Yazhi; Nakagawa, Hiroyuki; Kushiro, Masayo

2007-08-09

192

Landscape ecosystems of the University of Michigan Biological Station: Ecosystem diversity and ground-cover diversity  

SciTech Connect

The aim of this research is to provide an understanding of the three-dimensional (air-earth-organism) units of the landscape of the University of Michigan Biological Station (UMBS) that the author calls landscape ecosystem types, or simply ecosystems. Specifically, he has focused on the kinds, spatial location and patterns, and composition (physiography, soil, vegetation) of the local landscape ecosystem types of UMBS and Colonial Point. Future research on the functioning of these ecosystems together with inventories of their plant and animal life will add significantly to the landscape ecology research that has been initiated. A major reason for this research is to provide the conceptual basis and baseline data for understanding ecosystem change. Although it is popular to speak of climate change, entire ecosystems change; some components change faster than others.

Pearsall, D.R.

1995-12-31

193

ECOSYSTEM GROWTH AND DEVELOPMENT  

EPA Science Inventory

Thermodynamically, ecosystem growth and development is the process by which energy throughflow and stored biomass increase. Several proposed hypotheses describe the natural tendencies that occur as an ecosystem matures, and here, we consider five: minimum entropy production, maxi...

194

Physical and thermochemical properties of rice husk  

SciTech Connect

Rice husk a major by-product of the rice milling industry, is one of the most commonly available lignocellulosic materials that can be converted to different types of fuels and chemical feedstocks through a variety of thermochemical conversion processes. Proper understanding of the physical and thermochemical properties of rice husk is necessary for the design of thermochemical conversion systems. This study provides information on moisture content, bulk density, particle size, heating values, proximate analysis, ultimate analysis, ash composition, and ash fusibility characteristics for six rice husk varieties. The moisture content ranged from 8.68 to 10.44%, and the bulk density ranged from 86 to 114 kg/m{sup 3}. The results showed excessive volatile release of over 60%, high ash content ranging from 15.30 to 24.60% (dry weight basis), and high silica content of the ash ranging from 90 to 97%. The lower heating values ranged from 13.24 to 16.20 MJ/kg (dry weight basis). The ash fusion temperatures of all the varieties were found to be over 1,600 C. The differences in varietal characteristics have significant effects on the chemical properties of rice husk.

Mansaray, K.G.; Ghaly, A.E. [Technical Univ. of Nova Scotia, Halifax, Nova Scotia (Canada). Agricultural Engineering Dept.

1997-11-01

195

The short and the long of it: SD1 polymorphism and the evolution of growth trait divergence in U.S. weedy rice  

Technology Transfer Automated Retrieval System (TEKTRAN)

Growth related traits are thought to enhance competitiveness of agricultural weeds. U.S. weedy rice, a major conspecific weed of cultivated rice (Oryza sativa), displays variation for growth traits. Prior studies have shown that major U.S. weedy rice populations likely evolved from domesticated grou...

196

40 CFR Table 2b to Subpart Zzzz of... - Operating Limitations for New and Reconstructed 2SLB and Compression Ignition Stationary RICE...  

Code of Federal Regulations, 2011 CFR

...2SLB and Compression Ignition Stationary RICE >500 HP Located at a Major Source of...New and Reconstructed 4SLB Stationary RICE â¥250 HP Located at a Major Source of...Existing Compression Ignition Stationary RICE >500 HP, and Existing 4SLB...

2011-07-01

197

40 CFR Table 1b to Subpart Zzzz of... - Operating Limitations for Existing, New, and Reconstructed Spark Ignition 4SRB Stationary RICE...  

Code of Federal Regulations, 2011 CFR

...Reconstructed Spark Ignition 4SRB Stationary RICE >500 HP Located at a Major Source of...Existing Spark Ignition 4SRB Stationary RICE >500 HP Located at an Area Source of HAP...Reconstructed Spark Ignition 4SRB Stationary RICE >500 HP Located at a Major Source...

2011-07-01

198

The process of methylmercury accumulation in rice (Oryza sativa L.).  

PubMed

Recent studies have shown that rice consumption can be an important pathway of methylmercury (MeHg) exposure to humans in Hg mining areas and also in certain inland areas of Southwestern China. The seed of rice has the highest ability to accumulate MeHg compared to other tissues. The main objective of this study was to investigate the process of (MeHg) accumulation in rice seed (Oryza sativa L.) by monitoring MeHg levels in specific tissues of rice plants experiencing various levels of Hg multisource pollution during a full rice growing season. Four groups of experimental plantations were utilized, distributed among a rural artisanal Hg production site and a regional background control site. Our results suggest that the newly deposited Hg is more readily transformed to MeHg and accumulated in rice plants than Hg forms with an extended residence time in soil, and soil is the potential source of MeHg in the tissues of rice plants. MeHg in soil was first absorbed by roots and then translocated to the above-ground parts (leaf and stalk). During the full rice growing season only a very small amount of MeHg was retained in the root section. In the premature plant, the majority of MeHg is located in the leaf and stalk; however, most of this MeHg was transferred to seed during the ripening period. PMID:21366217

Meng, Bo; Feng, Xinbin; Qiu, Guangle; Liang, Peng; Li, Ping; Chen, Chunxiao; Shang, Lihai

2011-03-02

199

Biogeochemistry research needs: observations from the ecosystem studies program of The National Science Foundation  

Microsoft Academic Search

This comment presents current and emerging areas of research which the U.S. National Science Foundation believes have special promise for advancing ecosystem science. These areas are: (1) major element cycle interactions; (2) trace element and organic compound controls on ecosystem dynamics; (3) the role of consumers on ecosystem dynamics; (4) ecosystem dynamics in contrasting environments; (5) landscape ecology; and (6)

James R. Gosz

1986-01-01

200

A brief review of approaches using ciliated protists to assess aquatic ecosystem health  

Microsoft Academic Search

Ciliated protists are important components of marine and freshwater ecosystems. As such, their usefulness as indicators of aquatic ecosystem health has been recognized. Two major technical approaches have been employed: (1) community assessment, and (2) toxicological tests. Community assessment of an aquatic ecosystem must at least include comparisons to either baseline data on the ecosystem under study or to ‘pristine’

Denis H. Lynn; Guy L. Gilron

1992-01-01

201

Soil Carbon Turnover and the Net Ecosystem Carbon Balance of a Northern Hardwood Forest, Michigan, USA  

Microsoft Academic Search

Soils are a major reservoir of stored carbon (C) in forested ecosystems, containing up to 70% of total ecosystem C. Heterotrophic activity largely dictates the rate of soil C turnover and directly impacts ecosystem C balance. Reliable estimates of net ecosystem productivity (NEP) from ecophysiological and biometric data as well as the refinement of process-based models predicting belowground changes in

C. M. Gough; S. Biswas; C. S. Vogel; P. S. Curtis

2004-01-01

202

Populations and Ecosystems  

NSDL National Science Digital Library

This resource guide from the Middle School Portal 2 project, written specifically for teachers, provides links to exemplary resources including background information, lessons, career information, and related national science education standards. In this particular publications, students will explores topics such as different types of ecosystems, biological indicators, streams and life within them, micro ecosystems, terrestrial ecosystems, issues in ecology, and ecological footprints.

Lefever, Mary

2007-09-01

203

Biodiversity regulates ecosystem predictability  

Microsoft Academic Search

1-6 . Here we describe a previously unrecognized effect of biodiversity on ecosystem predictability, where predictability is inversely related to temporal and spatial variation in ecosystem properties. By manipulating biodiversity in aquatic microbial communities, we show that one process, ecosystem respiration, becomes more predictable as biodiversity increases. Analysis of similar patterns extracted from other studies 2,3,6 indicates that biodiversity also

Patricia M. Harris; Peter J. Morin

1997-01-01

204

40 CFR Table 1a to Subpart Zzzz of... - Emission Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE...  

Code of Federal Regulations, 2010 CFR

...Emission Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE >500 HP Located at a Major...Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE >500 HP Located at a...

2009-07-01

205

40 CFR Table 1a to Subpart Zzzz of... - Emission Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE...  

Code of Federal Regulations, 2010 CFR

...Emission Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE >500 HP Located at a Major...Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE >500 HP Located at a...

2010-07-01

206

40 CFR Table 1b to Subpart Zzzz of... - Operating Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE...  

Code of Federal Regulations, 2010 CFR

...Operating Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE >500 HP Located at a Major...Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE >500 HP Located at a...

2009-07-01

207

Developing rice mapping populations as a genetic resource for validation of GWAS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Asian rice (Oryza sativa L.) is divided into two major subspecies, Indica and Japonica with the temperate and tropical japonica subpopulations being part of Japonica. These two subpopulations encompass the majority of the rice grown in the USA. Recently, a genome-wide association study (GWAS) iden...

208

Rice research for food security and sustainable agricultural development in Asia: Achievements and future challenges  

Microsoft Academic Search

Rice is the major staple food of Asia, and an important source of employment and income in rural areas, particularly in low-income countries. Research has contributed significantly in achieving food security by increasing the yield potential of rice in irrigated systems, reducing the crop maturity period and achieving yield stability by developing resistance against major insects and diseases in the

K. S. Fischer

1995-01-01

209

Activation of eosinophils by rice-husk dust exposure: a possible mechanism for the aggravation of asthma during rice harvest.  

PubMed

Grain dust and other irritants affect the airway of allergic patients in rice-growing area during the harvest. The aim of this study was to elucidate the mechanism of airway hypersensitivity in rice-growing areas during the harvest. Firstly, the effect of rice-husk dust on eosinophil activation was studied. Secondary, the concentration of lipopolysaccharides (LPS), a potent activator of inflammatory cells, in rice-husk dust was measured. Since it is possible for LPS, a component of gram-negative bacterial cell wall, to adhere to the particle of smoke generated from rice-husk dust, LPS contained in the smoke was also measured. Furthermore, chemical irritants contained in the smoke generated from the rice-husk dust were analyzed. Microscopically, the dust contained fine thorns dropped off from the outer sheath of the rice, and irritated the skin, throat and eyes. The grain dust extract increased the expressions of eosinophil activation markers. These up-regulatory effects were largely dependent on LPS. The smoke contained LPS and several chemical irritants such as formaldehyde and acetaldehyde. Rice-husk dust and its smoke, hazardous air pollutants, probably play a major role in the aggravation of airway diseases in agricultural areas. PMID:15329460

Kayaba, Hiroyuki; Meguro, Hitomi; Muto, Hajime; Kamada, Yumiko; Adachi, Tetsuya; Yamada, Yoshiyuki; Kanda, Akira; Yamaguchi, Kazutoshi; Hamada, Kazuyuki; Ueki, Shigeharu; Chihara, Junichi

2004-09-01

210

Rice-based oral antibody fragment prophylaxis and therapy against rotavirus infection.  

PubMed

Rotavirus-induced diarrhea is a life-threatening disease in immunocompromised individuals and in children in developing countries. We have developed a system for prophylaxis and therapy against rotavirus disease using transgenic rice expressing the neutralizing variable domain of a rotavirus-specific llama heavy-chain antibody fragment (MucoRice-ARP1). MucoRice-ARP1 was produced at high levels in rice seeds using an overexpression system and RNAi technology to suppress the production of major rice endogenous storage proteins. Orally administered MucoRice-ARP1 markedly decreased the viral load in immunocompetent and immunodeficient mice. The antibody retained in vitro neutralizing activity after long-term storage (>1 yr) and boiling and conferred protection in mice even after heat treatment at 94°C for 30 minutes. High-yield, water-soluble, and purification-free MucoRice-ARP1 thus forms the basis for orally administered prophylaxis and therapy against rotavirus infections. PMID:23925294

Tokuhara, Daisuke; Álvarez, Beatriz; Mejima, Mio; Hiroiwa, Tomoko; Takahashi, Yuko; Kurokawa, Shiho; Kuroda, Masaharu; Oyama, Masaaki; Kozuka-Hata, Hiroko; Nochi, Tomonori; Sagara, Hiroshi; Aladin, Farah; Marcotte, Harold; Frenken, Leon G J; Iturriza-Gómara, Miren; Kiyono, Hiroshi; Hammarström, Lennart; Yuki, Yoshikazu

2013-08-08

211

Herbivory by resident geese: The loss and recovery of wild rice along the tidal Patuxent River  

USGS Publications Warehouse

Well known for a fall spectacle of maturing wild rice (Zizania aquatica) and migrant waterbirds, the tidal freshwater marshes of the Patuxent River, Maryland, USA, experienced a major decline in wild rice during the 1990s. We conducted experiments in 1999 and 2000 with fenced exclosures and discovered herbivory by resident Canada geese (Branta canadensis). Grazing by geese eliminated rice outside exclosures, whereas protected plants achieved greater size, density, and produced more panicles than rice occurring in natural stands. The observed loss of rice on the Patuxent River reflects both the sensitivity of this annual plant to herbivory and the destructive nature of an overabundance of resident geese on natural marsh vegetation. Recovery of rice followed 2 management actions: hunting removal of approximately 1,700 geese during a 4-year period and reestablishment of rice through a large-scale fencing and planting program.

Haramis, G. M.; Kearns, G.D.

2007-01-01

212

Rice-based oral antibody fragment prophylaxis and therapy against rotavirus infection  

PubMed Central

Rotavirus-induced diarrhea is a life-threatening disease in immunocompromised individuals and in children in developing countries. We have developed a system for prophylaxis and therapy against rotavirus disease using transgenic rice expressing the neutralizing variable domain of a rotavirus-specific llama heavy-chain antibody fragment (MucoRice-ARP1). MucoRice-ARP1 was produced at high levels in rice seeds using an overexpression system and RNAi technology to suppress the production of major rice endogenous storage proteins. Orally administered MucoRice-ARP1 markedly decreased the viral load in immunocompetent and immunodeficient mice. The antibody retained in vitro neutralizing activity after long-term storage (>1 yr) and boiling and conferred protection in mice even after heat treatment at 94°C for 30 minutes. High-yield, water-soluble, and purification-free MucoRice-ARP1 thus forms the basis for orally administered prophylaxis and therapy against rotavirus infections.

Tokuhara, Daisuke; ?lvarez, Beatriz; Mejima, Mio; Hiroiwa, Tomoko; Takahashi, Yuko; Kurokawa, Shiho; Kuroda, Masaharu; Oyama, Masaaki; Kozuka-Hata, Hiroko; Nochi, Tomonori; Sagara, Hiroshi; Aladin, Farah; Marcotte, Harold; Frenken, Leon G.J.; Iturriza-Gomara, Miren; Kiyono, Hiroshi; Hammarstrom, Lennart; Yuki, Yoshikazu

2013-01-01

213

Consideration of Ecosystem for ICME  

SciTech Connect

As the Integrated Computational Materials Engineering (ICME) emerges as a hot topic, computation, experimentation, and digital database are identified as its three major components. Efforts are being actively made from various aspects to bring ICME to reality. However, many factors that would affect ICEM development still remain vague. This paper is an attempt to discuss the needs for establishing a database centered ecosystem to facilitate ICEM development.

Ren, Weiju [ORNL

2013-01-01

214

Environments and Ecosystems  

NSDL National Science Digital Library

Students explore the biosphere and its associated environments and ecosystems in the context of creating a model ecosystem, learning along the way about the animals and resources. Students investigate different types of ecosystems, learn new vocabulary, and consider why a solid understanding of oneâs environment and the interdependence of an ecosystem can inform the choices we make and the way we engineer our communities. This lesson is part of a series of six lessons in which students use their growing understanding of various environments and the engineering design process, to design and create their own model biodome ecosystems.

Integrated Teaching And Learning Program

215

Landscape Modeling for Everglades Ecosystem Restoration  

Microsoft Academic Search

A major environmental restoration effort is under way that will affect the Everglades and its neighboring ecosystems in southern\\u000a Florida. Ecosystem and population-level modeling is being used to help in the planning and evaluation of this restoration.\\u000a The specific objective of one of these modeling approaches, the Across Trophic Level System Simulation (ATLSS), is to predict\\u000a the responses of a

Donald L. DeAngelis; Louis J. Gross; Michael A. Huston; Wilfried F. Wolff; D. Martin Fleming; E. Jane Comiskey; Scott M. Sylvester

1998-01-01

216

Conservation and Management of Tropical Coastal Ecosystems  

Microsoft Academic Search

All major coastal ecosystems in the tropics are being degraded. The problems include losses of biodiversity, reduced ecosystem\\u000a functions, and costs to coastal human societies. Declines in species’ abundances, and habitat loss and modification are the\\u000a result of the demands for aquaculture, port construction, trawling, excessive nutrient loads, overfishing and collecting,\\u000a sedimentation from catchment activities, invasive species, and climate change.

William Gladstone

217

Innate immunity in rice  

PubMed Central

Advances in studies of rice innate immunity have led to the identification and characterization of host sensors encoding receptor kinases that perceive conserved microbial signatures. The non-RD domain, a newly recognized hallmark of these receptor kinases is highly expanded in rice (Oryza sativa) compared with Arabidopsis (Arabidopsis thaliana). Researchers have also identified a diverse array of microbial effectors from bacterial and fungal pathogens that triggers immune responses upon perception. These include both, effectors that indirectly target host Nucleotide binding site/Leucine rice repeat (NBS-LRR) proteins and transcription activator-like (TAL) effectors that directly bind promoters of host genes. Here we review the recognition and signaling events that govern rice innate immunity.

Chen, Xuewei; Ronald, Pamela C.

2011-01-01

218

Herbicide sensitivity of Echinochloa spp. accessions in Italian rice fields  

Microsoft Academic Search

Echinochloa species are listed among the major weeds in rice worldwide. A greenhouse study was carried out on 80 accessions of Echinochloa collected in Italian rice fields to assess difference in response to azimsulfuron, bensulfuron-methyl, cyhalofop-butyl, molinate, propanil and quinclorac. The accessions were classified as Echinochloa crus-galli (L.) Beauv. (48 accessions; 60% of total), E. erecta (Pollacci) Pignatti (23 accessions;

F. Vidotto; F. Tesio; M. Tabacchi; A. Ferrero

2007-01-01

219

A PRELIMINARY CHARACTERIZATION OF THE RICE BLAST FUNGUS ON 'BANKS' RICE  

Technology Transfer Automated Retrieval System (TEKTRAN)

'Banks', named after Heartsill G. Banks (the first UA Rice Research and Extension Center (RREC) director in 1926), was released to seed growers during 2004. Developed at the RREC, Banks is a high yielding variety with the major blast resistance (R) gene Pi-ta and offers a primary advantage over LaG...

220

[Usefulness of hypoallergenic rice (AFT-R 1) and analysis of the salt insoluble rice allergen molecule].  

PubMed

An involvement of rice allergy in development and exacerbation of recalcitrant atopic dermatitis (AD) has been suggested in some cases, and it has been also known that elimination diet of rice results in improvement of AD and reduction of the doses of steroid ointment and anti-allergic drugs used for the treatment. We prepared the hypoallergenic rice grain, AFT-R 1 (Allergen-free Technology Lab. Inc.-Rice 1), with alkali treatment from the rice material, Koshihikari, which is popular in Japan. Its usefulness was evaluated clinically and serologically. The serological study with IgE-ELISA showed that the major allergic protein were remarkably reduced to less than 1/6400 of them in the AFT-R 1. Then it was applied to the clinical trial, and evaluated as useful by the clinical effect in 14 (93%) out of 15 patients, who were diagnosed to have rice allergy by the elimination (in 15 case) and ingestion (in 12 cases) of the regular rice. The serum taken from the patient, whom the AFT-R 1 was evaluated as unuseful in the clinical trial, was shown to have IgE antibodies reactive to the remaining protein in AFT-R 1 by IgE-ELISA, and the 60 kd protein band was detected as an IgE-binding component of AFT-R 1 by IgE-immunoblotting with the same serum. This 60 kd rice protein was identified as ADP (UDP)-glucose-starch glycosyl transferase (EC: 2.4.1.21) by N-terminal amino acid analysis. These results indicated that AFT-R 1 is very useful as a substitute of rice in many AD patients with rice allergy, although IgE-binding component such as the 60 kd protein is remaining in one. PMID:10331306

Ikezawa, Z; Tsubaki, K; Osuna, H; Shimada, T; Moteki, K; Sugiyama, H; Katumata, K; Anzai, H; Amano, S

1999-01-01

221

CELL BIOLOGY & MOLECULAR GENETICS Performance of Backcrosses Involving Transgressant Doubled Haploid Lines in Rice under Contrasting Moisture Regimes: Yield Components and Marker Heterozygosity  

Microsoft Academic Search

tomary statistical analyses are found to be inadequate in discerning the effects of different yield components Improvement of grain yield in the rainfed lowland rice (Oryza on yield (Zobel et al., 1989). Hence, studying grain yield sativa L.) ecosystem is important because that ecosystem covers a under varying moisture conditions and employing more considerable area. The objectives of this study

Mahmoud Toorchi; H. E. Shashidhar; T. M. Gireesha; Shailaja Hittalmani

222

Seeing Red: The Origin of Grain Pigmentation in US Weedy Rice  

PubMed Central

Weedy forms of crop species infest agricultural fields worldwide and are a leading cause of crop losses, yet little is known about how these weeds evolve. Red rice (Oryza sativa), a major weed of cultivated rice fields in the US, is recognized by the dark-pigmented grain that gives it its common name. Studies using neutral molecular markers have indicated a close relationship between US red rice and domesticated rice, suggesting that the weed may have originated through reversion of domesticated rice to a feral form. We have tested this reversion hypothesis by examining molecular variation at Rc, the regulatory gene responsible for grain pigmentation differences between domesticated and wild rice. Loss-of-function mutations at Rc account for the absence of proanthocyanidin pigments in cultivated rice grains, and the major rc domestication allele has been shown to be capable of spontaneous reversion to a functional form through additional mutations at the Rc locus. Using a diverse sample of 156 weedy, domesticated, and wild Oryzas, we analyzed DNA sequence variation at Rc and its surrounding 4 Mb genomic region. We find that reversion of domestication alleles does not account for the pigmented grains of weed accessions; moreover, we find that haplotypes characterizing the weed are either absent or very rare in cultivated rice. Sequences from genomic regions flanking Rc are consistent with a genomic footprint of the rc selective sweep in cultivated rice, and are compatible with a close relationship of red rice to Asian Oryzas that have never been cultivated in the US.

Gross, Briana L.; Reagon, Michael; Hsu, Shih-Chung; Caicedo, Ana L.; Jia, Yulin; Olsen, Kenneth M.

2010-01-01

223

Terrestrial Ecosystems of the Conterminous United States  

USGS Publications Warehouse

The U.S. Geological Survey (USGS), with support from NatureServe, has modeled the potential distribution of 419 terrestrial ecosystems for the conterminous United States using a comprehensive biophysical stratification approach that identifies distinct biophysical environments and associates them with known vegetation distributions (Sayre and others, 2009). This standardized ecosystem mapping effort used an ecosystems classification developed by NatureServe (Comer and others, 2003). The ecosystem mapping methodology was developed for South America (Sayre and others, 2008) and is now being implemented globally (Sayre and others, 2007). The biophysical stratification approach is based on mapping the major structural components of ecosystems (land surface forms, topographic moisture potential, surficial lithology, isobioclimates and biogeographic regions) and then spatially combining them to produce a set of unique biophysical environments. These physically distinct areas are considered as the fundamental structural units ('building blocks') of ecosystems, and are subsequently aggregated and labeled using the NatureServe classification. The structural footprints were developed from the geospatial union of several base layers including biogeographic regions, isobioclimates (Cress and others, 2009a), land surface forms (Cress and others, 2009b), topographic moisture potential (Cress and others, 2009c), and surficial lithology (Cress and others, in press). Among the 49,168 unique structural footprint classes that resulted from the union, 13,482 classes met a minimum pixel count threshold (20,000 pixels) and were aggregated into 419 NatureServe ecosystems using a semiautomated labeling process based on rule-set formulations for attribution of each ecosystem. The resulting ecosystems are those that are expected to occur based on the combination of the bioclimate, biogeography, and geomorphology. Where land use by humans has not altered land cover, natural vegetation assemblages are expected to occur, and these are described in the ecosystems classification. The map does not show the distribution of urban and agricultural areas - these will be masked out in subsequent analyses to depict the current land cover in addition to the potential distribution of natural ecosystems. This map depicts the smoothed and generalized image of the terrestrial ecosystems dataset. Additional information about this map and any data developed for the ecosystems modeling of the conterminous United States is available online at: http://rmgsc.cr.usgs.gov/ecosystems/.

Sayre, Roger; Comer, Patrick; Cress, Jill; Warner, Harumi

2010-01-01

224

A draft sequence of the rice ( Oryza sativa ssp. indica ) genome  

Microsoft Academic Search

The sequence of the rice genome holds fundamental information for its biology, including physiology, genetics, development,\\u000a and evolution, as well as information on many beneficial phenotypes of economic significance. Using a “whole genome shotgun”\\u000a approach, we have produced a draft rice genome sequence ofOryza sativa ssp.indica, the major crop rice subspecies in China and many other regions of Asia. The

Jun Yu; Songnian Hu; Jun Wang; Songgang Li; Ka-Shu Gane Wong; Bin Liu; Yajun Deng; Li Dai; Yan Zhou; Xiuqing Zhang; Mengliang Cao; Jing Liu; Jiandong Sun; Jiabin Tang; Yanjiong Chen; Xiaobing Huang; Wei Lin; Chen Ye; Wei Tong; Lijuan Cong; Jianing Geng; Yujun Han; Lin Li; Wei Li; Guangqiang Hu; Xiangang Huang; Wenjie Li; Jian Li; Zhanwei Liu; Long Li; Jianping Liu; Qiuhui Qi; Jinsong Liu; Li Li; Xuegang Wang; Hong Lu; Tingting Wu; Miao Zhu; Peixiang Ni; Hua Han; Wei Dong; Xiaoyu Ren; Xiaoli Feng; Peng Cui; Xianran Li; Hao Wang; Xin Xu; Wenxue Zhai; Zhao Xu; Jinsong Zhang; Sijie He; Jianguo Zhang; Jichen Xu; Kunlin Zhang; Xianwu Zheng; Jianhai Dong; Wanyong Zeng; Lin Tao; Xuewei Chen; Jun He; Daofeng Liu; Wei Tian; Chaoguang Tian; Hongai Xia; Gang Li; Hui Gao; Ping Li; Wei Chen; Xudong Wang; Yong Zhang; Jianfei Hu; Jing Wang; Song Liu; Jian Yang; Guangyu Zhang; Yuqing Xiong; Zhijie Li; Long Mao; Chengshu Zhou; Zhen Zhu; Runsheng Chen; Bailin Hao; Weimou Zheng; Shouyi Chen; Wei Guo; Guojie Li; Siqi Liu; Guyang Huang; Ming Tao; Jian Wang; Lihuang Zhu; Longping Yuan; Huanming Yang

2001-01-01

225

Succession of methanogenic archaea in rice straw incorporated into a Japanese rice field: estimation by PCR-DGGE and sequence analyses  

PubMed Central

The succession and phylogenetic profiles of methanogenic archaeal communities associated with rice straw decomposition in rice-field soil were studied by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis followed by 16S rDNA sequencing. Nylon bags containing either leaf sheaths or blades were buried in the plowed layer of a Japanese rice field under drained conditions during the off-crop season and under flooded conditions after transplanting. In addition, rice straw samples that had been buried in the rice field under drained conditions during the off-crop season were temporarily removed during spring plowing and then re-buried in the same rice field under flooded conditions at transplanting. Populations of methanogenic archaea were examined by amplification of the 16S rRNA genes in the DNA extracted from the rice straw samples. No PCR product was produced for samples of leaf sheath or blade prior to burial or after burial under drained conditions, indicating that the methanogen population was very small during decomposition of rice straw under oxic conditions. Many common bands were observed in rice straw samples of leaf sheath and blade during decomposition of rice straw under flooded conditions. Cluster analysis based on DGGE patterns divided methanogenic archaeal communities into two groups before and after the mid-season drainage. Sequence analysis of DGGE bands that were commonly present were closely related to Methanomicrobiales and Rice cluster I. Methanomicrobiales, Rice cluster I and Methanosarcinales were major members before the mid-season drainage, whereas the DGGE bands that characterized methanogenic archaeal communities after the mid-season drainage were closely related to Methanomicrobiales. These results indicate that mid-season drainage affected the methanogenic archaeal communities irrespective of their location on rice straw (sheath and blade) and the previous history of decomposition during the off-crop season.

Sugano, Atsuo; Tsuchimoto, Hidetaka; Cho, Tun Cho; Kimura, Makoto; Asakawa, Susumu

2005-01-01

226

Current status and future prospects in biological control of rice sheath blight in Mekong Delta  

Microsoft Academic Search

This research paper addresses the beneficial bacteria covering the aspects of biological control and plant growth promotion in terms of sheath blight (ShB) disease control. Six strains of beneficial bacteria (NF1, NF3, NF 52, NF 49, CT 6- 37, and W 23) were selected from 300 strains isolated from seeds and other components of the rice ecosystem in Mekong Delta.

Lai Van E; Nguyen Thi; Phong Lan; Pham Van Du; T. W. Mew

227

Global Conservation of Biodiversity and Ecosystem Services  

NSDL National Science Digital Library

This peer-reviewed article from the November 2007 issue of BioScience examines conservation strategies to preserve biodiversity and ecosystem services.Habitat destruction has driven much of the current biodiversity extinction crisis, and it compromises the essential benefits, or ecosystem services, that humans derive from functioning ecosystems. Securing both species and ecosystem services might be accomplished with common solutions. Yet it is unknown whether these two major conservation objectives coincide broadly enough worldwide to enable global strategies for both goals to gain synergy. In this article, we assess the concordance between these two objectives, explore how the concordance varies across different regions, and examine the global potential for safeguarding biodiversity and ecosystem services simultaneously. We find that published global priority maps for biodiversity conservation harbor a disproportionate share of estimated terrestrial ecosystem service value (ESV). Overlap of biodiversity priorities and ESV varies among regions, and in areas that have high biodiversity priority but low ESV, specialized conservation approaches are necessary. Overall, however, our findings suggest opportunities for safeguarding both biodiversity and ecosystem services. Sensitivity analyses indicate that results are robust to known limitations of available ESV data. Capitalizing on these opportunities will require the identification of synergies at fine scales, and the development of economic and policy tools to exploit them.

Will Turner (University of the Philippines;World Agroforestry Center); Katrina Brandon (University of the Philippines;World Agroforestry Center); Thomas Brooks (University of the Philippines;World Agroforestry Center); Robert Constanza (University of Vermont;Gund Institute for Ecological Economics); Gustavo da Fonseca (Federal University of Minas Gerais;); Rosimeiry Portela (;)

2007-11-01

228

Ecosystem Services - Water Purification  

NSDL National Science Digital Library

This lesson, provided by Science NetLinks, teaches students the importance of healthy ecosystems by investigating the example of natural water purification. Students will learn how ecosystems remove pollution from the water and how much it costs humans to do this artificially once ecosystems are no longer healthy. The class will then create a "River Newspaper" reporting on the condition of the local environment.

Science Netlinks;

2002-06-30

229

The Molecular Biology of Rice  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. New developments in rice molecular biology are enabling its use as a paradigmatical model for monocotyledonous plants. K. Shimamoto discusses progress in the Rice Genome Project, the first positional cloning of a rice gene [also reported in this issue of Science (Song et al., p. 1804)], and new cloning and transformation methods for rice.

Ko Shimamoto (Nara Institute of Science and Technology (NAIST);Laboratory of Plant Molecular Genetics)

1995-12-15

230

Genetic diversity of the two cultivated rice species ( O. sativa & O. glaberrima ) in Maritime Guinea. Evidence for interspecific recombination  

Microsoft Academic Search

In Maritime Guinea, the interpenetration of upland, lowland and mangrove rice growing ecosystems has found expression in the\\u000a cohabitation of the two rice cultivated species. Recent changes in cropping practices may lead to the replacement of local\\u000a varieties by modern high-yielding varieties. In the framework build-up of a strategy for the preservation of local varieties,\\u000a we analysed the extent, the

M. B. Barry; J. L. Pham; J. L. Noyer; C. Billot; B. Courtois; N. Ahmadi

2007-01-01

231

Riparian Ecosystems: A Preliminary Assessment of Their Importance, Status, and Needs.  

National Technical Information Service (NTIS)

This document was synthesized from an option paper developed by the Fish and Wildlife Service in May 1978 to assess major fish and wildlife issues associated with riparian ecosystems. The document contains chapters on ecosystems, fish and wildlfe dependen...

1980-01-01

232

Issues in Ecology, Issue 02: Ecosystem Services  

NSDL National Science Digital Library

This report defines ecosystem services as a strategy for the conservation of biodiversity. The production of ecosystem goods as it relates to the generation and maintenance of biodiversity is described. Ecosystem services such as flood and drought mitigation, services supplied by soil, pollination, pest control, and seed dispersal are described. Threats to ecosystem services are discussed, as well as their aesthetic, intellectual, and spiritual values. Issues in Ecology is an ongoing series of reports designed to present major ecological issues in an easy-to-read manner. This Issue summarizes the consensus of a panel of scientific experts based on the information that was current and available at the time of its publication in 1997.

Alexander, Susan

2010-02-16

233

Business modeling for service ecosystems  

Microsoft Academic Search

In this paper, we mainly propose a business model under the modeling framework for service ecosystems. We analyze the progress in modeling business ecosystems, digital ecosystems and service ecosystems. We point out the research gaps in modeling service ecosystems, especially those resulted from overlooking the essence of service. To address those gaps, we present an architecture of modeling framework for

Pingfeng Liu; Peilu Zhang; Guihua Nie

2010-01-01

234

Parallel Computing for Terrestrial Ecosystem Carbon Modeling  

SciTech Connect

Terrestrial ecosystems are a primary component of research on global environmental change. Observational and modeling research on terrestrial ecosystems at the global scale, however, has lagged behind their counterparts for oceanic and atmospheric systems, largely because the unique challenges associated with the tremendous diversity and complexity of terrestrial ecosystems. There are 8 major types of terrestrial ecosystem: tropical rain forest, savannas, deserts, temperate grassland, deciduous forest, coniferous forest, tundra, and chaparral. The carbon cycle is an important mechanism in the coupling of terrestrial ecosystems with climate through biological fluxes of CO{sub 2}. The influence of terrestrial ecosystems on atmospheric CO{sub 2} can be modeled via several means at different timescales. Important processes include plant dynamics, change in land use, as well as ecosystem biogeography. Over the past several decades, many terrestrial ecosystem models (see the 'Model developments' section) have been developed to understand the interactions between terrestrial carbon storage and CO{sub 2} concentration in the atmosphere, as well as the consequences of these interactions. Early TECMs generally adapted simple box-flow exchange models, in which photosynthetic CO{sub 2} uptake and respiratory CO{sub 2} release are simulated in an empirical manner with a small number of vegetation and soil carbon pools. Demands on kinds and amount of information required from global TECMs have grown. Recently, along with the rapid development of parallel computing, spatially explicit TECMs with detailed process based representations of carbon dynamics become attractive, because those models can readily incorporate a variety of additional ecosystem processes (such as dispersal, establishment, growth, mortality etc.) and environmental factors (such as landscape position, pest populations, disturbances, resource manipulations, etc.), and provide information to frame policy options for climate change impact analysis.

Wang, Dali [ORNL; Post, Wilfred M [ORNL; Ricciuto, Daniel M [ORNL; Berry, Michael [University of Tennessee, Knoxville (UTK)

2011-01-01

235

Rice irrigation and schistosomiasis in savannah and forest areas of Côte d'Ivoire.  

PubMed

Prevalence and intensity of infection of Schistosoma haematobium and Schistosoma mansoni were studied in relation to irrigated rice cultivation in Côte d'Ivoire. Urine and stool samples were collected from 4 to 15-year-old children in 24 villages in the savannah zone and 21 villages in the forest zone. Villages were classified according to surrounding inland valleys into three agro-ecosystems: (R2) full or partial water control allowing two rice cycles per year; (R1) no or partial water control allowing one harvest per year and (R0) absence of rice growing. In the savannah zone, S. haematobium prevalence was 4.8%, 2.3% and 0.7% and S. mansoni prevalence was 16.1%, 11.9% and 2.1% in R2, R1 and R0, respectively. In the forest zone, S. haematobium prevalence was 0.9%, 4.4% and 1.7% and S. mansoni prevalence was 61.3%, 46.6% and 17.5% in R2, in R1 and R0, respectively. Prevalences of S. mansoni adjusted for village effects were significantly different between agro-ecosystems in both zones. Significance of differences between agro-ecosystems of S. haematobium infection were strongly influenced by outlying villages. In savannah rice growing villages, negative binomial regression on infection intensity of each species showed significant positive relations to the surface of rice cultivated inland valleys, whereas uncultivated inland valleys showed no significant relation. However, in forest rice growing villages, S. mansoni infection intensity showed significant positive relations to the surface of uncultivated inland valleys, whereas surface water on rice cultivated land showed significant negative relations with infection intensity of each schistosomiasis species. PMID:15652334

Yapi, Y G; Briët, O J T; Diabate, S; Vounatsou, P; Akodo, E; Tanner, M; Teuscher, T

2004-12-22

236

Tagging and mapping of a rice gall midge resistance gene, Gm8 , and development of SCARs for use in marker-aided selection and gene pyramiding  

Microsoft Academic Search

Using amplified fragment length polymorphisms (AFLPs) and random amplified polymorphic DNAs (RAPDs), we have tagged and mapped Gm8, a gene conferring resistance to the rice gall midge ( Orseolia oryzae), a major insect pest of rice, onto rice chromosome 8. Using AFLPs, two fragments, AR257 and AS168, were identified that were linked to the resistant and susceptible phenotypes, respectively. Another

A. Jain; R. Ariyadasa; A. Kumar; M. N. Srivastava; M. Mohan; S. Nair

2004-01-01

237

40 CFR Table 2a to Subpart Zzzz of... - Emission Limitations for New and Reconstructed 2SLB and Compression Ignition Stationary RICE >500...  

Code of Federal Regulations, 2011 CFR

...Reconstructed 2SLB and Compression Ignition Stationary RICE >500 HP and New and Reconstructed 4SLB Stationary RICE â¥250 HP Located at a Major Source of HAP...Reconstructed 2SLB and Compression Ignition Stationary RICE >500 HP and New and Reconstructed 4SLB...

2011-07-01

238

Applying stable isotope probing of phospholipid fatty acids and rRNA in a Chinese rice field to study activity and composition of the methanotrophic bacterial communities in situ  

Microsoft Academic Search

Methanotrophs in the rhizosphere play an important role in global climate change since they attenuate methane emission from rice field ecosystems into the atmosphere. Most of the CH4 is emitted via transport through the plant gas vascular system. We used this transport for stable isotope probing (SIP) of the methanotrophs in the rhizosphere under field conditions and pulse-labelled rice plants

Qiongfen Qiu; Matthias Noll; Wolf-Rainer Abraham; Yahai Lu; Ralf Conrad

2008-01-01

239

Earth on Edge: Ecosystems  

NSDL National Science Digital Library

This site provides information about the six ecosystems on which life on Earth most heavily depends: agricultural, forest, freshwater, grassland, coastal, and urban. It is part of a Public Broadcasting System (PBS) project, which includes a discussion guide. Ecosystems are described as communities of interacting organisms and the physical environment in which they live. The goods and services that ecosystems provide are said to form the foundation of human economies. Ecosystems purify air and water, help to control climate, and produce valuable soil-services. Site users may access a discussion guide to accompany the broadcast of the video/television program, which can be used in colleges, secondary schools, and in community groups. Case studies are taken from the companion book, World Resources 2000-2001: Ecosystems and People: The Fraying Web of Life, and from Pilot Analysis of Global Ecosystems: Agroecosystems (World Resources Institute). This online text includes profiles, case studies, and ecosystem assessments with references to ecosystems around the world. A list of additional resources includes links to environmental organizations, books, and periodicals.

Overton, Janet

240

Ecosystems emerging: 1. conservation  

Microsoft Academic Search

This second paper in the series on Ecosystems Emerging treats some properties of ecosystems derivable from the single elementary principle of conservation. These go beyond the mere balancing out of the matter and forces of nature.A brief sketch of a conservationless world is given, followed by an elementary background review of energy, matter and information. The main conservative quantities are

Bernard C. Patten; Milan Straškraba; Sven E. Jørgensen

1997-01-01

241

Science Sampler: Ecosystem Jenga!  

NSDL National Science Digital Library

To give students a tangible model of an ecosystem and have them experience what could happen if a component of that ecosystem were removed; the authors developed a hands-on, inquiry-based activity that visually demonstrates the concept of a delicately bal

Leslie-Pelecky, Diandra L.; Rousseau, Joe; Umphlett, Natalie; Laungani, Ramesh; Brosius, Tierney

2009-09-01

242

What Is Ecosystem Management?  

Microsoft Academic Search

The evolving concept of ecosystem management is the focus of much current debate. To clarify discussion and provide a frammork for implementatiotq I trace the histor- ical development of ecosystem management, provide a working definitioq and summarize dominant themes taken from an extensive literature reuiew. The general goal of maintaining ecological integ?Yty is discussed along with five specific goals: maintaining

R. Edward Grumbine

1994-01-01

243

Molecular evolution of shattering loci in U.S. weedy rice  

PubMed Central

Cultivated rice fields worldwide are plagued with weedy rice, a conspecific weed of cultivated rice (Oryza sativa L.). The persistence of weedy rice has been attributed, in part, to its ability to shatter (disperse) seed prior to crop harvesting. In the United States, separately evolved weedy rice groups have been shown to share genomic identity with exotic domesticated cultivars. Here, we investigate the shattering phenotype in a collection of U.S. weedy rice accessions, as well as wild and cultivated relatives. We find that all U.S. weedy rice groups shatter seeds easily, despite multiple origins, and in contrast to a decrease in shattering ability seen in cultivated groups. We assessed allelic identity and diversity at the major shattering locus, sh4, in weedy rice; we find that all cultivated and weedy rice, regardless of population, share similar haplotypes at sh4, and all contain a single derived mutation associated with decreased seed shattering. Our data constitute the strongest evidence to date of an evolution of weeds from domesticated backgrounds. The combination of a shared cultivar sh4 allele and a highly shattering phenotype, suggests that U.S. weedy rice have re-acquired the shattering trait after divergence from their progenitors through alternative genetic mechanisms.

Thurber, Carrie S.; Reagon, Michael; Gross, Briana L.; Olsen, Kenneth M.; Jia, Yulin; Caicedo, Ana L.

2010-01-01

244

Molecular evolution of shattering loci in U.S. weedy rice.  

PubMed

Cultivated rice fields worldwide are plagued with weedy rice, a conspecific weed of cultivated rice (Oryza sativa L.). The persistence of weedy rice has been attributed, in part, to its ability to shatter (disperse) seed prior to crop harvesting. In the United States, separately evolved weedy rice groups have been shown to share genomic identity with exotic domesticated cultivars. Here, we investigate the shattering phenotype in a collection of U.S. weedy rice accessions, as well as wild and cultivated relatives. We find that all U.S. weedy rice groups shatter seeds easily, despite multiple origins, and in contrast to a decrease in shattering ability seen in cultivated groups. We assessed allelic identity and diversity at the major shattering locus, sh4, in weedy rice; we find that all cultivated and weedy rice, regardless of population, share similar haplotypes at sh4, and all contain a single derived mutation associated with decreased seed shattering. Our data constitute the strongest evidence to date of an evolution of weeds from domesticated backgrounds. The combination of a shared cultivar sh4 allele and a highly shattering phenotype, suggests that U.S. weedy rice have re-acquired the shattering trait after divergence from their progenitors through alternative genetic mechanisms. PMID:20584132

Thurber, Carrie S; Reagon, Michael; Gross, Briana L; Olsen, Kenneth M; Jia, Yulin; Caicedo, Ana L

2010-06-24

245

Southern rice black-streaked dwarf virus: a white-backed planthopper-transmitted fijivirus threatening rice production in Asia  

PubMed Central

Southern rice black-streaked dwarf virus (SRBSDV), a non-enveloped icosahedral virus with a genome of 10 double-stranded RNA segments, is a novel species in the genus Fijivirus (family Reoviridae) first recognized in 2008. Rice plants infected with this virus exhibit symptoms similar to those caused by Rice black-streaked dwarf virus. Since 2009, the virus has rapidly spread and caused serious rice losses in East and Southeast Asia. Significant progress has been made in recent years in understanding this disease, especially about the functions of the viral genes, rice–virus–insect interactions, and epidemiology and control measures. The virus can be efficiently transmitted by the white-backed planthopper (WBPH, Sogatella furcifera) in a persistent circulative propagative manner but cannot be transmitted by the brown planthopper (Nilaparvata lugens) and small brown planthopper (Laodelphax striatellus). Rice, maize, Chinese sorghum (Coix lacryma-jobi) and other grass weeds can be infected via WBPH. However, only rice plays a major role in the virus infection cycle because of the vector’s preference. In Southeast Asia, WBPH is a long-distance migratory rice pest. The disease cycle can be described as follows: SRBSDV and its WBPH vector overwinter in warm tropical or sub-tropical areas; viruliferous WBPH adults carry the virus from south to north via long-distance migration in early spring, transmit the virus to rice seedlings in the newly colonized areas, and lay eggs on the infected seedlings; the next generation of WBPHs propagate on infected seedlings, become viruliferous, disperse, and cause new disease outbreaks. Several molecular and serological methods have been developed to detect SRBSDV in plant tissues and individual insects. Control measures based on protection from WBPH, including seedbed coverage, chemical seed treatments, and chemical spraying of seedlings, have proven effective in China.

Zhou, Guohui; Xu, Donglin; Xu, Dagao; Zhang, Maoxin

2013-01-01

246

Overview on current status of biotechnological interventions on yellow stem borer Scirpophaga incertulas (Lepidoptera: Crambidae) resistance in rice.  

PubMed

Yellow stem borer (YSB), Scirpophaga incertulas (Lepidoptera: Crambidae), a monophagous pest of paddy is considered as most important pest of rain fed low land and flood prone rice eco-systems. Breeding of yellow stem borer resistance in rice is difficult owing to the complex genetics of the trait, inherent difficulties in screening and poor understanding of the genetics of resistance. On the other hand, a good level of resistance against the widespread yellow stem borer has been rare in the rice germplasm. Resistance to insects has been demonstrated in transgenic plants expressing genes for delta-endotoxins from Bacillus thuringiensis (Bt), protease inhibitors, enzymes and plant lectins. The performance of insect resistant GM rice in trials in China has been quite impressive. The present review is an attempt to assess the current state of development in biotechnological intervention for yellow stem borer resistance in rice. PMID:19811767

Deka, Sikha; Barthakur, Sharmistha

247

Coral Reef Ecosystems  

NASA Astrophysics Data System (ADS)

Coral reefs are geological structures of significant dimensions, constructed over millions of years by calcifying organisms. The present day reef-builders are hard corals belonging to the order Scleractinia, phylum Cnidaria. The greatest concentrations of coral reefs are in the tropics, with highest levels of biodiversity situated in reefs of the Indo-West Pacific region. These ecosystems have provided coastal protection and livelihood to human populations over the millennia. Human activities have caused destruction of these habitats, the intensity of which has increased alarmingly since the latter decades of the twentieth century. The severity of this impact is directly related to exponential growth rates of human populations especially in the coastal areas of the developing world. However, a more recently recognized phenomenon concerns disturbances brought about by the changing climate, manifested mainly as rising sea surface temperatures, and increasing acidification of ocean waters due to greater drawdown of higher concentrations of atmospheric carbon dioxide. Management efforts have so far not kept pace with the rates of degradation, so that the spatial extent of damaged reefs and the incidences of localized extinction of reef species are increasing year after year. The major management efforts to date consist of establishing marine protected areas and promoting the active restoration of coral habitats.

Yap, Helen T.

248

SEVEN PILLARS OF ECOSYSTEM MANAGEMENT  

EPA Science Inventory

Ecosystem management is widely proposed in the popular and professional literature as the modern and preferred way of managing natural resources and ecosystems. Advocates glowingly describe ecosystem management as an approach that will protect the environment, maintain healthy ec...

249

Quantitative trait loci for root-penetration ability and root thickness in rice: comparison of genetic backgrounds.  

PubMed

Drought is the major abiotic stress limiting rice (Oryza sativa) production and yield stability in rainfed lowland and upland ecosystems. Root systems play an important role in drought resistance. Incorporation of root selection criteria in drought resistance improvement is difficult due to lack of reliable and efficient screening techniques. Using a wax-petrolatum layer system simulated to compacted soil layers, root traits were evaluated in a doubled haploid (DH) population derived from the cross between 'IR64' and 'Azucena'. Twelve putative QTLs (quantitative trait loci) were detected by interval mapping comprising four QTLs for root-penetration ability, four QTLs for root thickness, two QTLs for penetrated root number, and two QTLs for total root number. These QTLs individually explained 8.4% to 16.4% of the phenotypic variation. No QTL was detected for maximum penetrated root length by interval mapping. One QTL located between RG104 and RG348 was found to influence both root-penetration ability and root thickness. QTLs for root-penetration ability and root thickness were compared across two populations, 'IR64'-'Azucena' and 'CO39'-'Moroberekan', and different testing conditions. The identified consistent QTLs could be used for marker-assisted selection for deep and thick roots with high root-penetration ability in rice. PMID:10701113

Zheng, H G; Babu, R C; Pathan, M S; Ali, L; Huang, N; Courtois, B; Nguyen, H T

2000-02-01

250

Seeing red: The origin of grain pigmentation in US weedy rice  

Technology Transfer Automated Retrieval System (TEKTRAN)

Red rice (Oryza sativa L.) is the major weed of cultivated rice fields in the US, where it causes tens of millions of dollars in crop losses annually. This weedy crop-relative is characterized by several traits that are typical of wild Oryza species, including the anthocyanin-pigmented pericarp tha...

251

Arsenic content of various types of rice as determined by plasma-based techniques  

Microsoft Academic Search

The determination of total As in rice is of special importance because rice forms a major dietary staple for many populations and contains a relatively high amount of this element as compared to other foodstuffs. Arsenic is in fact abundant in many minerals and its compounds are frequently employed in the chemical industry for producing pharmaceuticals, agricultural chemicals (herbicides, fungicides,

S. D'Ilio; M. Alessandrelli; R. Cresti; G. Forte; S. Caroli

2002-01-01

252

Weed suppression potential of 'Rondo' and other indica rice germplasm lines  

Technology Transfer Automated Retrieval System (TEKTRAN)

A high-yielding indica rice, 'Rondo' (4484-1693; PI 657830) which carries resistances to major rice diseases, was previously developed. We evaluated the weed suppression potential of Rondo, a sister line (4484-1665), and other indica lines against barnyardgrass in field plots in Stuttgart, AR, using...

253

Effects of abscisic acid on ozone tolerance of rice ( Oryza sativa L.) seedlings  

Microsoft Academic Search

Ozone is one of the major gaseous pollutants detrimental to crop growthand metabolism. The objective of this research was to study how ABA amelioratesthe effects of ozone on rice seedlings. Seedlings of two rice cultivars withdifferent sensitivities to ozone (Tainung 67, tolerant; and Taichung Native 1,sensitive) were treated with 400 ppb of ozone or ABA and 400ppb of ozone to

Dai-Ing Lin; Huu-Sheng Lur; Chun Chu

2001-01-01

254

Grain yield responses to moisture regimes in a rice population: association among traits and genetic markers  

Microsoft Academic Search

Drought is a major constraint to rice (Oryza sativa L.) production in rainfed and poorly irrigated environments. Identifying genomic regions influencing the response of yield and its components to water deficits will aid our understanding of the genetic mechanism of drought tolerance (DT) of rice and the development of DT varieties. Grain yield (GY) and its components of a recombinant

G. H. Zou; H. W. Mei; H. Y. Liu; G. L. Liu; S. P. Hu; X. Q. Yu; M. S. Li; J. H. Wu; L. J. Luo

2005-01-01

255

Evaluation of Commercially Available PGPR for Control of Rice Sheath Blight Caused by Rhizoctonia solani  

Microsoft Academic Search

Sheath blight disease of rice caused by Rhizoctonia solani is a major production constraint in all rice producing areas of the world. The annual losses due to sheath blight are estimated to be 25 % under optimum conditions of disease development. Disease management is currently focused on extensive use of fungicides which has created concerns about environmental pollution, pathogen resistance

K. Vijay Krishna Kumar; S. Krishnam Raju; M. S. Reddy; J. W. Kloepper; K. S. Lawrence; D. E. Groth; M. E. Miller; H. Sudini; Binghai Du

2009-01-01

256

Simulating the fate of molinate in rice paddies using the RICEWQ model  

Microsoft Academic Search

The contamination of drainage channels and creeks with pesticides used in the production of rice is of concern in south eastern Australia. Of major concern is the molinate that at times has been detected in over 25% of water samples from surface drains and creeks. The objective of this study was to evaluate the rice pesticide model RICEWQ version 1.7.2

Evan W. Christen; Sang-Ok Chung; Wendy Quayle

2006-01-01

257

Yield and Soil Nutrient Changes in a Long-Term Rice-Wheat Rotation in India  

Microsoft Academic Search

ganic nutrient sources on yield trends of rice and wheat, nutrient balances, and soil nutrient pools, and (ii) iden- Major improvements in the productivity of rice (Oryza sativa L.) tify reasons for the yield trends observed. and wheat (Triticum aestivum L.) have occurred in South Asia since 1965-1966 when the Green Revolution began. However, after the 1980s, yield stagnated or

A. L. Bhandari; J. K. Ladha; H. Pathak; A. T. Padre; D. Dawe; R. K. Gupta

2002-01-01

258

Quantitative trait loci analysis for rice seed vigor during the germination stage*  

PubMed Central

Seed vigor is an important characteristic of seed quality, and rice cultivars with strong seed vigor are desirable in direct-sowing rice production for optimum stand establishment. In the present study, the quantitative trait loci (QTLs) of three traits for rice seed vigor during the germination stage, including germination rate, final germination percentage, and germination index, were investigated using one recombinant inbred line (RIL) population derived from a cross between japonica Daguandao and indica IR28, and using the multiple interval mapping (MIM) approach. The results show that indica rice presented stronger seed vigor during the germination stage than japonica rice. A total of ten QTLs, and at least five novel alleles, were detected to control rice seed vigor, and the amount of variation (R 2) explained by an individual QTL ranged from 7.5% to 68.5%, with three major QTLs with R 2>20%. Most of the QTLs detected here are likely to coincide with QTLs for seed weight, seed size, or seed dormancy, suggesting that the rice seed vigor might be correlated with seed weight, seed size, and seed dormancy. At least five QTLs are novel alleles with no previous reports of seed vigor genes in rice, and those major or minor QTLs could be used to significantly improve the seed vigor by marker-assisted selection (MAS) in rice.

Wang, Zhou-fei; Wang, Jian-fei; Bao, Yong-mei; Wang, Fu-hua; Zhang, Hong-sheng

2010-01-01

259

Red Rices - Past, Present, and Future  

Microsoft Academic Search

Rices with a red bran layer are called red rices. This paper briefly reviews the history, definition, and types of red rices; the uses of red rices as food and medicine, and their role in cultural and religious ceremonies; the varieties of red rices, areas of cultivation, and their use in breeding programs for the improvement of cultivated varieties; and

Uma Ahuja; SC Ahuja; Narender Chaudhary; Rashmi Thakrar

260

Arsenic, Organic Foods, and Brown Rice Syrup  

PubMed Central

Background: Rice can be a major source of inorganic arsenic (Asi) for many sub-populations. Rice products are also used as ingredients in prepared foods, some of which may not be obviously rice based. Organic brown rice syrup (OBRS) is used as a sweetener in organic food products as an alternative to high-fructose corn syrup. We hypothesized that OBRS introduces As into these products. Objective: We determined the concentration and speciation of As in commercially available brown rice syrups and in products containing OBRS, including toddler formula, cereal/energy bars, and high-energy foods used by endurance athletes. Methods: We used inductively coupled plasma mass spectrometry (ICP-MS) and ion chromatography coupled to ICP-MS to determine total As (Astotal) concentrations and As speciation in products purchased via the Internet or in stores in the Hanover, New Hampshire, area. Discussion: We found that OBRS can contain high concentrations of Asi and dimethyl-arsenate (DMA). An “organic” toddler milk formula containing OBRS as the primary ingredient had Astotal concentrations up to six times the U.S. Environmental Protection Agency safe drinking water limit. Cereal bars and high-energy foods containing OBRS also had higher As concentrations than equivalent products that did not contain OBRS. Asi was the main As species in most food products tested in this study. Conclusions: There are currently no U.S. regulations applicable to As in food, but our findings suggest that the OBRS products we evaluated may introduce significant concentrations of Asi into an individual’s diet. Thus, we conclude that there is an urgent need for regulatory limits on As in food.

Taylor, Vivien F.; Karagas, Margaret R.; Punshon, Tracy; Cottingham, Kathryn L.

2012-01-01

261

Recovery of marine animal populations and ecosystems.  

PubMed

Many marine populations and ecosystems have experienced strong historical depletions, yet reports of recoveries are increasing. Here, we review the growing research on marine recoveries to reveal how common recovery is, its magnitude, timescale and major drivers. Overall, 10-50% of depleted populations and ecosystems show some recovery, but rarely to former levels of abundance. In addition, recovery can take many decades for long-lived species and complex ecosystems. Major drivers of recovery include the reduction of human impacts, especially exploitation, habitat loss and pollution, combined with favorable life-history and environmental conditions. Awareness, legal protection and enforcement of management plans are also crucial. Learning from historical recovery successes and failures is essential for implementing realistic conservation goals and promising management strategies. PMID:21852017

Lotze, Heike K; Coll, Marta; Magera, Anna M; Ward-Paige, Christine; Airoldi, Laura

2011-08-17

262

The Logic and Realism of the Hypothesis of Exploitation Ecosystems  

Microsoft Academic Search

Hypotheses on trophic dynamics in terrestrial ecosystems fall into two major categories: those in which plants are assumed to be invulnerable to their consumers and those in which the build-up of plant biomass is assumed to require top-down control of folivores. The hypothesis of exploitation ecosystems (EEH) belongs to the latter category and focuses particularly on the consequences of the

Lauri Oksanen; Tarja Oksanen

2000-01-01

263

An introduction to the European Terrestrial Ecosystem Modelling Activity  

Microsoft Academic Search

The objective of the European Terrestrial Eco- system Modelling Activity (ETEMA) was to address some of the major challenges in developing generalized models to examine responses of natural and seminatural ecosystems to environmental change at the regional to European scale. The approach described herein was to break down the totality of ecosystem functioning into its key components, each with its

MARTIN T. SYKES; I. COLIN PRENTICE; BENJAMIN SMITH; WOLFGANG CRAMER; SERGEY VENEVSKY; Max Planck

2001-01-01

264

El Niño effects on the dynamics of terrestrial ecosystems  

Microsoft Academic Search

New studies are showing that the El Niño Southern Oscillation (ENSO) has major implications for the functioning of different ecosystems, ranging from deserts to tropical rain forests. ENSO-induced pulses of enhanced plant productivity can cascade upward through the food web invoking unforeseen feedbacks, and can cause open dryland ecosystems to shift to permanent woodlands. These insights suggest that the predicted

Milena Holmgren; Marten Scheffer; Exequiel Ezcurra; Julio R. Gutiérrez; Godefridus M. J. Mohren

2001-01-01

265

Rice Outlook, July 2008.  

National Technical Information Service (NTIS)

There were several revisions to the 2008/09 U.S. rough-rice balance sheet this month. First, the season-average farm price (SAFP) was lowered 20 cents per hundredweight (cwt) on both the high and low ends to $16.30-$17.30 per cwt, still the highest on rec...

N. Childs

2008-01-01

266

Rice Outlook, December 2007.  

National Technical Information Service (NTIS)

There were no supply-side revisions this month. Total U.S. rice supplies in 2007/08 are projected to be up slightly from a year earlier, as a larger crop and record imports more than offset a smaller carryin. Medium/short-grain account for all of the supp...

N. Childs

2007-01-01

267

Rice Outlook, January 2008.  

National Technical Information Service (NTIS)

The only supply-side revision this month was a 0.5 million cwt reduction in the 2007/08 rough-rice crop estimate to 197.5 million, a result of a lower yield estimate. Despite the downward revision, the average field yield is the highest on record. Yields ...

N. Childs

2008-01-01

268

Rice Outlook, April 2008.  

National Technical Information Service (NTIS)

The March 2008 'Prospective Plantings' report indicated 2008 U.S. rice plantings at 2.77 million acres, an increase of just 9,000 acres from a year earlier and the second smallest since 1989. Both long- and combined medium/short-grain plantings were indic...

N. Childs

2008-01-01

269

RICE MICROSTRUCTURE - COMPARING CULTIVARS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The microstructures of short, medium, long and waxy grain rices were compared for microstructural characteristics using scanning electron and light microscopies. The cultivars in this study included three short grain (Akitakamachi, Koshihikari and S102); three medium grain (Bengal, M202 and M401); f...

270

RICE STRAW CHARACTERIZATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

The structure of rice straw is described using scanning electron and light microscopy. The monocotyledonous plant consists of multiple leaf structures which sheath an interior, hollow stem. All tissues have large air spaces and many of the cells are lignified. The exterior surfaces contain multiple ...

271

Direct Seeding of Rice  

Microsoft Academic Search

Rice (Oryza sativa L.), a staple food for more than half of the world population, is commonly grown by transplanting seedlings into puddled soil (wet tillage) in Asia. This production system is labor-, water-, and energy-intensive and is becoming less profitable as these resources are becoming increasingly scarce. It also deteriorates the physical properties of soil, adversely affects the performance

Virender Kumar; Jagdish K. Ladha

2011-01-01

272

MULTIPLE INLET RICE IRRIGATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Conventional flooded rice production consists of a well or riser in the highest-elevation portion of the field. Contour levees are constructed at approximately every 0.2 ft in elevation drop and adjustable spills are placed in the levees. When water is released from the well or riser, it flows over ...

273

Exploring Japan through Rice.  

ERIC Educational Resources Information Center

Explores the role of rice in Japanese culture by presenting historical background and teaching activities in a variety of categories, such as language, sociology, history, and contemporary politics. Suggests teachers create cross-cultural comparisons; for example, the role of corn in the United States. Provides a list of teacher resources. (CMK)

Wojtan, Linda S.

1998-01-01

274

One-step multiplex reverse transcription-polymerase chain reaction for the simultaneous detection of three rice viruses.  

PubMed

Rice stripe virus (RSV), Rice black-streaked dwarf virus (RBSDV), and Rice dwarf virus (RDV) are major rice-infecting viruses in Korea that can cause serious crop losses. A one-step multiplex reverse transcription-polymerase chain reaction (mRT-PCR) was developed for the simultaneous detection of these rice viruses. Three sets of specific primers targeted to the capsid protein coding genes of RSV, RBSDV, and RDV were used to amplify fragments that were 703bp, 485bp, and 252bp, respectively. The one-step mRT-PCR assay proved to be a sensitive and rapid method for detecting the three rice viruses. This method could be used to facilitate better control of rice viruses. PMID:23850700

Cho, Sang-Yun; Jeong, Rae-Dong; Yoon, Young-Nam; Lee, Su-Heon; Shin, Dong Bum; Kang, Hang-Won; Lee, Bong Choon

2013-07-11

275

Lessons on River Ecosystems  

NSDL National Science Digital Library

The lesson activity titles are: What are systems? (Purpose: to have students understand what a "system" is, in the broadest sense) How is the natural environment of the tribal community a system? (Purpose: to tie what students learned during the year about the tribal community and its natural environment to the concept of what a "system" is) How did settlers of European descent change the tribe's ecosystem? (Purpose: to explore the connections between what European settlers did to the tribe's ecosystem and what the effects have been on the ecosystem) What can be done? What should be done? (Purpose: to explore and evaluate policy options for future environmental sustenance)

Zalles, Dan

276

Modulating rice stress tolerance by transcription factors.  

PubMed

Plants are non-mobile organisms and have to adapt to environmental stresses mostly by modulating their growth and development in addition to physiological and biochemical changes. Transcription factors (TFs) regulate genome expression in response to environmental and physiological signals, and some of them switch on plant adaptive developmental and physiological pathways. One TF is encoded by a single gene but regulates the expression of several other genes leading to the activation of complex adaptive mechanisms and hence represents major molecular targets to genetically improve the tolerance of crop plants against different stresses. In this review an updated account of the discovery of TFs involved in biotic and abiotic stress tolerance in the model monocotyledonous plant, rice (Oryza sativa L.) is presented. We illustrate how the elucidation of the function of these TFs can be used to set up genetic engineering strategies and to rationalize molecular breeding using molecular assisted selection towards enhancement of rice tolerance to various stresses. Attempts have also been made to provide information on the molecular mechanisms involved in stress resistance or tolerance processes. We discuss how the comparison of the action of TFs isolated from the dicotyledonous model plant Arabidopsis thaliana in rice and vice versa can contribute to determine whether common or divergent mechanisms underlie stress tolerance in the two plant species. Lastly, we discuss the necessity to discover TFs controlling specifically the root adaptive development which constitutes a major way for the plant to escape to several stresses such as water deficit or mineral nutrient deficiency. PMID:21412363

Khong, Giang; Richaud, Frédérique; Coudert, Yoan; Pati, Pratap K; Santi, Carole; Périn, Christophe; Breitler, Jean-Christophe; Meynard, Donaldo; Vinh, Do N; Guiderdoni, Emmanuel; Gantet, Pascal

2008-01-01

277

[Ecosystem evolution: main stages and potential mechanisms].  

PubMed

Major differences between the Western and "Russian" (Zavarzin, 1995) paradigms in ecology and evolutionary biology are described. The "Russian" paradigm suggests that there exist two, rather than one, quite independent lineages--species evolution and ecosystem evolution. This is based on the idea that life may exist just as a nutrient cycle. The main terms and concepts of the "Russian" paradigm are defined more exactly. An attempt is made to develop this paradigm so that it would be possible to describe not only phenomenology, but also mechanisms of ecosystem evolution. To simplify evolutionary phenomena logically, it is suggested to use the concept of conditionally complete causal explanation (Lekevicius, 1984; 1985), i.e. deduce evolutionary mechanisms from major principles of functioning. This methodology is adapted to model the main stages of the evolution of nutrient cycles (3.8-2.0 bln. y.a.) and the appearance and evolution of biophagy (1.7-0 bln. y.a.). Based on a multitude of examples, it is shown that these are functional constraints that are the forces directing evolution; those constraints emerge during the interaction of organisms and while the latter interact with the abiotic environment. Since the structure of an ecosystem is non-rigid, each species is able to accumulate features useful to both an ecosystem and itself. Those are individuals that die and reproduce, whereas all structures, from macromolecules to ecosystems, evolve. PMID:14598527

Lekiavichius, E

278

Broader perspective on ecosystem sustainability: consequences for decision making.  

PubMed

Although the concept of ecosystem sustainability has a long-term focus, it is often viewed from a static system perspective. Because most ecosystems are dynamic, we explore sustainability assessments from three additional perspectives: resilient systems; systems where tipping points occur; and systems subject to episodic resetting. Whereas foundations of ecosystem resilience originated in ecology, recent discussions have focused on geophysical attributes, and it is recognized that dynamic system components may not return to their former state following perturbations. Tipping points emerge when chronic changes (typically anthropogenic, but sometimes natural) push ecosystems to thresholds that cause collapse of process and function and may become permanent. Ecosystem resetting occurs when episodic natural disasters breach thresholds with little or no warning, resulting in long-term changes to environmental attributes or ecosystem function. An example of sustainability assessment of ecosystem goods and services along the Gulf Coast (USA) demonstrates the need to include both the resilient and dynamic nature of biogeomorphic components. Mountain road development in northwest Yunnan, China, makes rivers and related habitat vulnerable to tipping points. Ecosystems reset by natural disasters are also presented, emphasizing the need to understand the magnitude frequency and interrelationships among major disturbances, as shown by (i) the 2011 Great East Japan Earthquake and resulting tsunami, including how unsustainable urban development exacerbates geodisaster propagation, and (ii) repeated major earthquakes and associated geomorphic and vegetation disturbances in Papua New Guinea. Although all of these ecosystem perturbations and shifts are individually recognized, they are not embraced in contemporary sustainable decision making. PMID:23686583

Sidle, Roy C; Benson, William H; Carriger, John F; Kamai, Toshitaka

2013-05-17

279

Stabilizing Unmilled Brown Rice by Ethanol Extraction.  

National Technical Information Service (NTIS)

The invention is drawn to a highly advantageous and unobvious process for stabilizing unmilled brown rice comprising, contacting unmilled brown rice with ethanol under conditions providing extraction of 15% or less of brown rice oil from the unmilled brow...

E. T. Champagne R. J. Hron G. Abraham

1990-01-01

280

Major depression  

MedlinePLUS

Depression - major; Unipolar depression; Major depressive disorder ... The exact cause of depression is not known. Many researchers believe it is caused by chemical changes in the brain. This may be due to ...

281

Characterization of volatile aroma compounds in cooked black rice.  

PubMed

Black rice ( Oryza sativa L.), an aromatic specialty rice popular in Asia, has a unique flavor, the volatile chemistry of which has not been reported. The objectives of this research were to study volatile profiles of cooked black rice and to characterize the odor-active compounds. Thirty-five volatile compounds were identified by gas chromatography-mass spectrometry using a dynamic headspace system with Tenax trapping. Aldehydes and aromatics were quantitatively in the greatest abundance, accounting for 80.1% of total relative concentration of volatiles. The concentration of 2-acetyl-1-pyrroline (2-AP) was high, exceeded only by hexanal, nonanal, and 2-pentylfuran. A total of 25 odor-active compounds, determined by gas chromatography-olfactometry, were applied to principal component analysis, demonstrating significant differences between a black and a traditional white rice cultivar in terms of aroma and explaining 93.0% of the total variation. 2-AP, guaiacol, indole, and p-xylene largely influenced the difference between the aroma in cooked black and white rice. 2-AP and guaiacol were major contributors to the unique character of black rice based on odor thresholds, relative concentrations, and olfactometry. PMID:18081248

Yang, Dong Sik; Lee, Kyu-Seong; Jeong, O-Young; Kim, Kee-Jong; Kays, Stanley J

2007-12-15

282

[Transgenic rice breeding for abiotic stress tolerance--present and future].  

PubMed

Environmental stresses and the continuing deterioration of arable land, along with an explosive increase in world population, pose serious threats to global agricultural production and food security. Improving the tolerance of the major crop plants to abiotic stresses has been a main goal in agriculture for a long time. As rice is considered one of the major crops, the development of new cultivars with enhanced abiotic stress-tolerance will undoubtedly have an important effect on global food production. The transgenic approach offers an attractive alternative to conventional techniques for the genetic improvement of rice cultivars. In recent years, an array of stress-related genes has already been transferred to rice to improve its resistance against abiotic stresses. Many transgenic rice plants with enhanced abiotic stress-tolerance have been obtained. This article focuses on the progress in the study of abiotic stress tolerance in transgenic rice breeding. PMID:17366880

Zhao, Feng-Yun; Zhang, Hui

2007-01-01

283

Ecosystems in the Laboratory  

ERIC Educational Resources Information Center

|Describes the materials and laboratory techniques for the study of food chains and food webs, pyramids of numbers and biomass, energy pyramids, and oxygen gradients. Presents a procedure for investigating the effects of various pollutants on an entire ecosystem. (GS)|

Madders, M.

1975-01-01

284

Light Pollution and Ecosystems  

NSDL National Science Digital Library

Artificial light at night acts as a pollutant, with significant and adverse impacts to ecosystems. It can, for example, cause disorientation or act as an unnatural stimulus to wildlife, and disrupt reproduction for many species.

Travis Longcore (University of Southern California;)

2010-05-20

285

Principles of Ecosystem Management.  

National Technical Information Service (NTIS)

The protection of estuarine ecosystems requires a comprehensive coastal zone management program with specific environmental controls set within this larger framework. The coastal flood-plain may be designated an area of environmental concern, or conservat...

J. Clark P. J. Sarokwash

1975-01-01

286

Limiting Factors in Ecosystems  

NSDL National Science Digital Library

This unit, designed to span two class periods, helps students understand that physical factors, particularly temperature and precipitation, limit the growth of plant ecosystems. The activity begins with a discussion in which students develop their own ideas about the role of temperature, precipitation, and environment on plant growth. They will then examine X-Y graphs of vegetation growth, temperature, and precipitation versus month for four diverse ecosystems to determine which climatic factor is limiting growth. A worksheet and scoring rubric are provided.

287

Delineation of ecosystem regions  

Microsoft Academic Search

As a means of developing reliable estimates of ecosystem productivity, ecosystem classification needs to be placed within a geographical framework of regions or zones. This paper explains the basis for the regions delineated on the 1976 mapEcoregions of the United States. Four ecological levels are discussed—domain, division, province, and section—based on climatic and vegetational criteria. Statistical tests are needed to

Robert G. Bailey; Fort Collins

1983-01-01

288

Ecosystem thresholds with hypoxia  

Microsoft Academic Search

Hypoxia is one of the common effects of eutrophication in coastal marine ecosystems and is becoming an increasingly prevalent\\u000a problem worldwide. The causes of hypoxia are associated with excess nutrient inputs from both point and non-point sources,\\u000a although the response of coastal marine ecosystems is strongly modulated by physical processes such as stratification and\\u000a mixing. Changes in climate, particularly temperature,

Daniel J. Conley; Jacob Carstensen; Raquel Vaquer-Sunyer; Carlos M. Duarte

2009-01-01

289

General Equilibrium of an Ecosystem  

Microsoft Academic Search

Ecosystems and economies are inextricably linked: ecosystem models and economic models are not linked. Consequently, using either type of model to design policies for preserving ecosystems or improving economic performance omits important information. Improved policies would follow from a model that links the systems and accounts for the mutual feedbacks by recognizing how key ecosystem variables influence key economic variables,

JOHN TSCHIRHART

2000-01-01

290

Agrobacterium-mediated co-transformation of rice using two selectable marker genes derived from rice genome components.  

PubMed

A method for Agrobacterium-mediated co-transformation of rice (Oryza sativa L.) was developed using rice-derived selection markers. Two T-DNAs were efficiently introduced into separate loci using selectable marker gene cassettes consisting of the mutated acetolactate synthase gene (mALS) under the control of the callus-specific promoter (CSP) (CSP:mALS) and the ferredoxin nitrite reductase gene (NiR) under the control of its own promoter (NiR P:NiR). The CSP:mALS gene cassette confers sulfonylurea herbicide resistance to transgenic rice callus. The NiR P:NiR construct complements NiR-deficient mutant cultivars such as 'Koshihikari', which are defective in the regulation of nitrogen metabolism. In the present study, the CaMV35S:GUS and CaMV35S:GFP gene cassettes were co-introduced into the 'Koshihikari' genome using our system. Approximately 5-10 independent transgenic lines expressing both the GUS and GFP reporters were obtained from 100 Agrobacterium co-inoculated calli. Furthermore, transgenic 'Koshihikari' rice lines with reduced content of two major seed allergen proteins, the 33 and 14-16 kDa allergens, were generated by this co-transformation system. The present results indicate that the generation of selectable antibiotic resistance marker gene-free transgenic rice is possible using our rice-derived selection marker co-transformation system. Key message An improved rice transformation method was developed based on Agrobacterium-mediated co-transformation using two rice genome-derived selectable marker gene cassettes. PMID:22843026

Wakasa, Yuhya; Ozawa, Kenjirou; Takaiwa, Fumio

2012-07-28

291

Climate Change As An Ecosystem Architect: Implications To Rare ...  

Treesearch

Title: Climate Change As An Ecosystem Architect: Implications To Rare Plant ... Research Center USDA Forest Service, Pacific Southwest Research Station ... major migrations, range shifts, and population extirpations and colonizations (up to ...

292

On the generality of stability–complexity relationships in Lotka–Volterra ecosystems  

Microsoft Academic Search

Understanding how complexity persists in nature is a long-standing goal of ecologists. In theoretical ecology, local stability is a widely used measure of ecosystem persistence and has made a major contribution to the ecosystem stability–complexity debate over the last few decades. However, permanence is coming to be regarded as a more satisfactory definition of ecosystem persistence and has relatively recently

Sunny E. Townsend; Daniel T. Haydon; Louise Matthews

2010-01-01

293

Estimates of ecosystem productions from coordinated flux measurements and satellite data  

Microsoft Academic Search

Carbon cycle of terrestrial ecosystem is a fundamental process that shape biogeochemical cycles and land-atmosphere interactions at global and regional scales. Gross primary production and net ecosystem production are important parameters of carbon cycle of terrestrial ecosystems. Over past years, major achievements have been made to estimate primary productions with satellite data at global scales. However, those estimates were often

G. Jia; H. Wang; A. Zhang

2010-01-01

294

Anti-oxidative analysis, and identification and quantification of anthocyanin pigments in different coloured rice.  

PubMed

Anthocyanin pigments in coloured rice cultivars were isolated and identified using high-performance liquid chromatography techniques. Two black rice cultivars (Asamurasaki, Okunomurasaki) contained three major anthocyanins: cyanidin-3-glucoside, peonidin-3-glucoside and malvidin. Chinakuromai (black) rice additionally contained a fourth anthocyanin, petunidin-3-glucoside. Four red rice cultivars contained only malvidin. The total anthocyanin content varied greatly among black rice cultivars (79.5-473.7 mg/100g), but was lower in red rice (7.9-34.4 mg/100g). Total phenolic content was similar between red (460.32-725.69 mg/100g) and black (417.11-687.24 mg/100g) rice. The oxygen radical absorbing capacity was ranked as follows: red (69.91-130.32 ?mol Trolox/g)>black (55.49-64.85 ?mol Trolox/g)>green (35.32 ?mol Trolox/g)>white (21.81 ?mol Trolox/g) rice. The antioxidant capacity resulted mainly from the seed capsule, not the endosperm. The anthocyanin pigments contributed little to the total antioxidant capacity of red (0.03-0.1%) and black (0.5-2.5%) rice cultivars. Hence, the antioxidant capacity is derived mainly from other phenolic compounds. PMID:22980872

Chen, Xiao Qiong; Nagao, Norio; Itani, Tomio; Irifune, Kohei

2012-07-06

295

Ecosystems, Biomes, and Watersheds: Definitions and Use  

NSDL National Science Digital Library

This paper discusses the meaning and applications of the term "ecosystem" and of the related terms "watershed" and "biome". It discusses the pros and cons of all three as organizing principles for land management, and the major issues likely to arise in the debate over ecosystem management as an approach to management of land and water resources, natural resources, and biological diversity. This paper, a Congressional Research Service (CRS) Report, is produced to provide nonpartisan research reports to members of the U. S. Congress, and is also made available to the public.

Corn, M.

296

Molecular evolution of the TAC1 gene from rice (Oryza sativa L.).  

PubMed

Tiller angle is a key feature of the architecture of cultivated rice (Oryza sativa), since it determines planting density and influences rice yield. Our previous work identified Tiller Angle Control 1 (TAC1) as a major quantitative trait locus that controls rice tiller angle. To further clarify the evolutionary characterization of the TAC1 gene, we compared a TAC1-containing 3164-bp genomic region among 113 cultivated varieties and 48 accessions of wild rice, including 43 accessions of O. rufipogon and five accessions of O. nivara. Only one single nucleotide polymorphism (SNP), a synonymous substitution, was detected in TAC1 coding regions of the cultivated rice varieties, whereas one synonymous and one nonsynonymous SNP were detected among the TAC1 coding regions of wild rice accessions. These data indicate that little natural mutation and modification in the TAC1 coding region occurred within the cultivated rice and its progenitor during evolution. Nucleotide diversities in the TAC1 gene regions of O. sativa and O. rufipogon of 0.00116 and 0.00112, respectively, further indicate that TAC1 has been highly conserved during the course of rice domestication. A functional nucleotide polymorphism (FNP) of TAC1 was only found in the japonica rice group. A neutrality test revealed strong selection, especially in the 3'-flanking region of the TAC1 coding region containing the FNP in the japonica rice group. However, no selection occurred in the indica and wild-rice groups. A phylogenetic tree derived from TAC1 sequence analysis suggests that the indica and japonica subspecies arose independently during the domestication of wild rice. PMID:23089365

Jiang, Jiahuan; Tan, Lubin; Zhu, Zuofeng; Fu, Yongcai; Liu, Fengxia; Cai, Hongwei; Sun, Chuanqing

2012-09-16

297

Neglecting Rice Milling Yield and Quality Underestimates Economic Losses from High-Temperature Stress  

PubMed Central

Future increases in global surface temperature threaten those worldwide who depend on rice production for their livelihoods and food security. Past analyses of high-temperature stress on rice production have focused on paddy yield and have failed to account for the detrimental impact of high temperatures on milling quality outcomes, which ultimately determine edible (marketable) rice yield and market value. Using genotype specific rice yield and milling quality data on six common rice varieties from Arkansas, USA, combined with on-site, half-hourly and daily temperature observations, we show a nonlinear effect of high-temperature stress exposure on yield and milling quality. A 1°C increase in average growing season temperature reduces paddy yield by 6.2%, total milled rice yield by 7.1% to 8.0%, head rice yield by 9.0% to 13.8%, and total milling revenue by 8.1% to 11.0%, across genotypes. Our results indicate that failure to account for changes in milling quality leads to understatement of the impacts of high temperatures on rice production outcomes. These dramatic losses result from reduced paddy yield and increased percentages of chalky and broken kernels, which together decrease the quantity and market value of milled rice. Recently published estimates show paddy yield reductions of up to 10% across the major rice-producing regions of South and Southeast Asia due to rising temperatures. The results of our study suggest that the often-cited 10% figure underestimates the economic implications of climate change for rice producers, thus potentially threatening future food security for global rice producers and consumers.

Lyman, Nathaniel B.; Jagadish, Krishna S. V.; Nalley, L. Lanier; Dixon, Bruce L.; Siebenmorgen, Terry

2013-01-01

298

Water management affects arsenic and cadmium accumulation in different rice cultivars.  

PubMed

Paddy rice (Oryza sativa L.) is a staple food and one of the major sources of dietary arsenic (As) and cadmium (Cd) in Asia. A field experiment was conducted to investigate the effects of four water management regimes (aerobic, intermittent irrigation, conventional irrigation and flooding) on As and Cd accumulation in seven major rice cultivars grown in Zhejiang province, east China. With increasing irrigation from aerobic to flooded conditions, the soil HCl-extractable As concentrations increased significantly and the HCl-extractable Cd concentrations decreased significantly. These trends were consistent with the As and Cd concentrations in the straw, husk and brown rice. Water management both before and after the full tillering stage affected As and Cd accumulation in the grains. The intermittent and conventional treatments produced higher grain yields than the aerobic and flooded treatments. Cd concentrations in brown rice varied 13.1-40.8 times and As varied 1.75-8.80 times among the four water management regimes. Cd and As accumulation in brown rice varied among the rice cultivars, with Guodao 6 (GD6) was a low Cd but high-As-accumulating cultivar while Indonesia (IR) and Yongyou 9 (YY9) were low As but high-Cd-accumulating cultivars. Brown rice Cd and As concentrations in the 7 cultivars were significantly negatively correlated. The results indicate that As and Cd accumulated in rice grains with opposite trends that were influenced by both water management and rice cultivar. Production of 'safe' rice with respect to As and Cd might be possible by balancing water management and rice cultivar according to the severity of soil pollution. PMID:23719663

Hu, Pengjie; Huang, Jiexue; Ouyang, Younan; Wu, Longhua; Song, Jing; Wang, Songfeng; Li, Zhu; Han, Cunliang; Zhou, Liqiang; Huang, Yujuan; Luo, Yongming; Christie, Peter

2013-05-30

299

Retrotransposon families in rice  

Microsoft Academic Search

Three families of retrotransposons of rice (Tos1,Tos2, andTos3) were isolated by using a method based on the sequence conservation of the primer binding site for reverse transcription. This method should be generally applicable for cloning retrotransposons of other plants. One retrotransposon,Tos3-1, was studied in detail.Tos3-1 is 5.2 kb long, has structures common to retrotransposons, such as long terminal repeats (LTR),

Hirohiko Hirochika; Atsushi Fukuchi; Fumio Kikuchi

1992-01-01

300

Analysis of rice ( Oryza sativa L.) genome using pulsed-field gel electrophoresis and rare-cutting restriction endonucleases  

Microsoft Academic Search

TheOryza sativa (rice) genome is small (600 to 900 megabase pairs) when compared to that of other monocotyledonous plants. Rice was the first\\u000a of the major cereals to be successfully transformed and regenerated. An RFLP map with approximately 300 markers is readily\\u000a available, and the DNA content per map unit is only two to three times that ofArabidopsis thaliana. Rice

Bruno W. S. Sobral; Rhonda J. Honeycutt; Alan G. Atherly; Michael McClelland

1990-01-01

301

Sodium and potassium uptake of rice panicles as affected by salinity and season in relation to yield and yield components  

Microsoft Academic Search

Salinity is a major yield-reducing stress in many arid and\\/or coastal irrigation systems for rice. Past studies on salt stress\\u000a have mainly addressed the vegetative growth stage of rice, and little is known on salt effects on the reproductive organs.\\u000a Sodium and potassium uptake of panicles was studied for eight rice cultivars in field trials under irrigation with saline\\u000a and

Folkard Asch; Michael Dingkuhn; Christine Wittstock; Karl Doerffling

1999-01-01

302

Energy flow in an arctic aquatic ecosystem  

SciTech Connect

This project has been using natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. We are processing samples collected at the R4D intensive site over the past three years and are comparing these data with similar samples collected from the coastal plain. Our approach is to determine if carbon is accumulating in upland and coastal tundra; to determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers.

Schell, D.M.

1993-05-01

303

Energy flow in an arctic aquatic ecosystem  

SciTech Connect

This project has been using natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. We are processing samples collected at the R4D intensive site over the past three years and are comparing these data with similar samples collected from the coastal plain. Our approach is to determine if carbon is accumulating in upland and coastal tundra; to determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers.

Schell, D.M.

1993-01-01

304

Isotopic disequilibrium between carbon assimilated and respired in a rice paddy as influenced by methanogenesis from CO2  

Microsoft Academic Search

Temporal variability in the carbon isotope composition of ecosystem respiration (?R) has been closely related to environmental variables that influence photosynthetic isotope discrimination (?). We show that belowground methanogenesis has a strong impact on ?R and leads to a partial decoupling between ?R and ?. The ?R, observed in a Japanese rice paddy, varied from ?26.3‰ to ?22.8‰ over the

G. H. Han; H. Yoshikoshi; H. Nagai; T. Yamada; K. Ono; M. Mano; A. Miyata

2007-01-01

305

Comparison of partial and complete soil K budgets under intensive rice cropping in the Mekong Delta, Vietnam  

Microsoft Academic Search

Crop response to added fertilizer K was often found to be small in trials conducted on favorable soils of tropical rice ecosystems. Hence, applications of only fertilizer N and P were recommended. This has resulted in soil K mining in intensive cropping systems in China, India and other Asian countries. Prediction of possible K deficiency in the future requires knowledge

Nguyen My Hoa; Bert H. Janssen; Oene Oenema; Achim Dobermann

2006-01-01

306

STORAGE BEHAVIOR OF RICE AND RICE BRAN IN HERMETICALLY SEALED CONTAINER  

Microsoft Academic Search

This paper discusses results of laboratory trials exploring benefits derived from hermetic storage of brown rice, milled rice at various milling degrees and rice bran. Thirty three glass jars containing one kilogram of rice and rice bran were used as hermetic storage vessels. Metal jar covers were modified to create a \\

CECILIA V. DE DIOS; DANILO G. NATIVIDAD; EVANGELINE A. TAMPOC; LARRY G. JAVIER

307

Conservation of rice genetic resources: the role of the International Rice Genebank at IRRI  

Microsoft Academic Search

Rice genetic resources, comprising landrace varieties, modern and obsolete varieties, genetic stocks, breeding lines, and the wild rices, are the basis of world food security. The International Rice Genebank at the International Rice Research Institute in the Philippines conserves the largest and most diverse collection of rice germplasm. The facilities of the genebank ensure the long-term preservation of this important

Michael T. Jackson

1997-01-01

308

Effects of acetic acid on the rice gelatinization and pasting properties of rice starch during cooking  

Microsoft Academic Search

The mechanism of the textural changes such as increase in stickiness of rice cooked with acetic acid was studied focusing on the gelatinization and rheological properties of both rice starch and rice flour. The results of swelling power and solubility of rice starch indicated that acetic acid promoted water absorption of amylopectin in rice starch. It was shown by DSC

Kyoko Ohishi; Midori Kasai; Atsuko Shimada; Keiko Hatae

2007-01-01

309

Comparison of chemical compositions and bioactive compounds of germinated rough rice and brown rice  

Microsoft Academic Search

The aim of the study was to compare changes in the chemical compositions and bioactive compounds of germinated rough rice and germinated brown rice. Ungerminated rice (brown rice) and germinated rice extract powder were also prepared, for comparison purposes. In general, the concentration of crude protein, total free amino acids, ?-tocopherol, ?-oryzanol, thiamine, niacin and pyridoxine, in the germinated rough

Anuchita Moongngarm; Nattawat Saetung

2010-01-01

310

[Exposure degree of important non-target arthropods to Cry2Aa in Bt rice fields].  

PubMed

Based on the principle of "risk = hazard x exposure", the selected representative nontarget organisms in the assessment of the potential effects of insect-resistant genetically modified (GM) crops on non-target arthropods in laboratory are generally the arthropod species highly exposed to the insecticidal proteins expressed by the GM crops in farmland ecosystem. In order to understand the exposure degree of the important arthropod species to Cry proteins in Bt rice fields, and to select the appropriate non-target arthropods in the risk assessment of insect-resistant GM crops, the enzyme-linked immunosorbent assay (ELISA) was conducted to measure the Cry2Aa protein concentration in the arthropods collected from the cry2Aa rice fields at different rice growth stages. The results showed that there was a significant difference in the Cry2Aa content protein concentration in different arthropod species. Some species did not contain Cry2Aa protein, while some species contained larger amounts of Cry2Aa protein. Relative to the arthropods colleted after rice anthesis, the arthropods colleted in rice anthesis contained relative higher concentrations of Cry2Aa protein, especially for the predacious arthropods. No Cry proteins were detected in parasitic arthropods. This study provided references for the laboratory assessment of the effects of GM rice on nontarget arthropods. PMID:24066553

Zhang, Qing-Ling; Li, Yun-He; Hua, Hong-Xia; Yang, Chang-Ju; Wu, Hong-Jin; Peng, Yu-Fa

2013-06-01

311

The African Contribution to Rice Cultivation in the Americas  

Microsoft Academic Search

In the last three decades, successive books by Peter H. Wood, Daniel C. Littlefield and Judith A. Carney have progressively made the case that the major export crop of eighteenth-century South Carolina and Georgia was predominantly a creation of Africans. This African contribution to New World agriculture is epitomized by the arresting title of Carney's book: Black Rice. A direct

David Eltis; Philip Morgan; David Richardson

312

Mitochondrial DNA modifications associated with cytoplasmic male sterility in rice  

Microsoft Academic Search

Mitochondrial DNA was isolated from fertile and cytoplasmic male sterile lines of rice. Restriction analysis showed specific modifications in the male sterile cytoplasm. In addition to the major mitochondrial DNA, three small plasmid-like DNA molecules were detected by agarose gel electrophoresis in both cytoplasms. An additional molecule was specifically found in the sterile cytoplasm. These mitochondrial DNA modifications support the

H. Mignouna; S. S. Virmani; M. Briquet

1987-01-01

313

DEVELOPMENT OF MOLECULAR STRATEGIES TO CONTROL RICE SHEATH BLIGHT DISEASE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Little is known about mechanisms of molecular interaction of host with the necrotrophic pathogen Rhizoctonia solani. After a detailed analysis of the pathogen population in the major rice producing state, Arkansas, the most virulent field isolate was identified among 124 characterized isolates. Th...

314

A hydroponic rice seedling culture model system for investigating proteome of salt stress in rice leaf.  

PubMed

By using an in vivo hydroponic rice seedling culture system, we investigated the physiological and biochemical responses of a model rice japonica cultivar Nipponbare to salt stress using proteomics and classical biochemical methods. Yoshida's nutrient solution (YS) was used to grow rice seedlings. YS-grown 18-day-old seedlings manifested highly stable and reproducible symptoms, prominently the wilting and browning of the 3rd leaf, reduced photosynthetic activity, inhibition in overall seedling growth, and failure to develop new (5th) leaf, when subjected to salt stress by transferring them to YS containing 130 mM NaCl for 4 days. As leaf response to salt stress is least investigated in rice by proteomics, we used the 3rd leaf as source material. A comparison of 2-DE protein profiles between the untreated control and salt-stressed 3rd leaves revealed 55 differentially expressed CBB-stained spots, where 47 spots were increased over the control. Of these changed spots, the identity of 33 protein spots (27 increased and 5 decreased) was determined by nESI-LC-MS/MS. Most of these identified proteins belonged to major metabolic processes like photosynthetic carbon dioxide assimilation and photorespiration, suggesting a good correlation between salt stress-responsive proteins and leaf morphology. Moreover, 2-DE immunoblot and enzymatic activity analyses of 3rd leaves revealed remarkable changes in the key marker enzymes associated with oxidative damage to salt stress: ascorbate peroxidase and lipid peroxidation were induced, and catalase was suppressed. These results demonstrate that hydroponic culture system is best suited for proteomics of salt stress in rice seedling. PMID:16315177

Kim, Dea-Wook; Rakwal, Randeep; Agrawal, Ganesh Kumar; Jung, Young-Ho; Shibato, Junko; Jwa, Nam-Soo; Iwahashi, Yumiko; Iwahashi, Hitoshi; Kim, Du Hyun; Shim, Ie-Sung; Usui, Kenji

2005-12-01

315

Ecosystem Structure and Survival  

NASA Astrophysics Data System (ADS)

Ecosystem survival through chronic and/or episodic water stress requires not only physiological adaptations by the vegetation to the water stress but also an accessible store of water removed from environmental evaporative demand. The existence of such a store at depth is corroborated by recent observations from many biomes, including the seasonally-dry Amazon, which show enhanced productivity during the dry season thanks to hydraulic redistribution of soil water resources by deep-rooted trees. Additionally, we present new hydrologic observations from a small, steep, temperate forested watershed along the Northern Californian coast. The differences between upslope and downslope hydrology and ecosystem dynamics suggest that ecosystem resilience may be dependent on diverse functional and structural attributes of plants, which are species dependent. These plant attributes may, in addition, reflect plant adaptation to, and plant modification of, the local hydrologic setting that feeds back on other biogeochemical cycles and even on climate.

Fung, I.; Lee, J.; Dawson, T. E.

2008-12-01

316

RICE: Rapid interconnect circuit evaluator  

Microsoft Academic Search

This paper describes RICE, an RLC interconnect evaluation tool based upon the moment-matching teehnique of Asymptotic Waveform Evaluation (AWE). The RLC circuit moments are calculated by a path-tracing algorithm which enables the analysis of large interconnect models several thousand times faster than a circuit simulation while requiring 5 to 10 times less memory. RICE also includes anew approach for determining

Curtis L. Ratzlaff; Nanda Gopal; Lawrence T. Pillage

1991-01-01

317

Simulating Leaf Appearance in Rice  

Microsoft Academic Search

Most rice (Oryza sativa L.) simulation models assume that only temperature aff ects leaf appearance rate (LAR). Th is assumption ignores results from controlled environment studies that show that LAR in rice is not constant with time (calendar days) under constant temperature. Th e Streck model, which takes into account age eff ects on LAR, improved the prediction of leaf

Nereu Augusto Streck; Leosane Cristina Bosco; Isabel Lago

2008-01-01

318

Panicle Rice Mite Program Manual.  

National Technical Information Service (NTIS)

Panicle Rice Mite Program Manual is used as a guide when designing a program to detect, monitor, control, contain, or eradicate an infestation of this pest. If panicle rice mite (Steneotarsonemus spinki Smiley) (PRM) is detected in the United States, PPQ ...

2009-01-01

319

MILLED RICE FISSURE FORMATION KINETICS  

Microsoft Academic Search

Milled rice samples at various moisture contents (MCs) were exposed to air inside a chamber that was equipped with a video camera and monitoring system that enabled observation of fissure formation over a 24-h exposure duration. The effects of milled rice kernel MC (11%, 12%, 13%, or 14%), cultivar (Bengal, Wells, and CL161), air relative humidity (RH; 10%, 20%, 30%,

T. J. Siebenmorgen; M. I. Saleh; R. C. Bautista

320

Hydraulic conductivity of rice roots  

Microsoft Academic Search

A pressure chamber and a root pressure probe technique have been used to measure hydraulic conductivities of rice roots (root Lpr per m 2 of root surface area). Young plants of two rice (Oryza sativa L.) varieties (an upland variety, cv. Azucena and a lowland variety, cv. IR64) were grown for 31-40 d in 12 h days with 500 mmol

Naoko Miyamoto; Ernst Steudle; Tadashi Hirasawa; Renee Lafitte

2001-01-01

321

Construction of rice cybrid plants  

Microsoft Academic Search

The mitochondrial genomes of rice cells were transferred to a fertile rice variety (N8) from a cytoplasmic male sterile variety (CMS) by asymmetric protoplast fusion based on metabolic complementation. Protoplasts derived from CMS were X-irradiated (125 krad) and electrofused with protoplasts which had been treated with iodoacetamide. Metabolic complementation, presumably between nuclear and cytoplasmic compartments, enabled fused protoplasts to form

Hiromori Akagi; Masahiro Sakamoto; Tomoko Negishi; Tatsuhito Fujimura

1989-01-01

322

Columbia River Estuary Ecosystem Classification Ecosystem Complex  

USGS Publications Warehouse

Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub-catena". The extent of detailed mapping is the interpreted Holocene geologic floodplain of the tidal Columbia River and its tributaries to the estimated head of tide. The extent of this dataset also includes tributary valleys that are not mapped in detail. The upstream extents of tributary valleys are an estimation of the limit of Columbia River influence and are for use as containers in future analyses. The geologic floodplain is the geomorphic surface that is actively accumulating sediment through occasional overbank deposition. Most features within the geologic floodplain are considered to be formed during the recent (Holocene-epoch) climatic regime. There are bedrock and pre-Holocene sedimentary deposits included where they are surrounded by Holocene sediment accumulations or have been shaped by Holocene floods. In some places, Holocene landforms such as landslides, tributary fans, and coastal dunes are mapped that extend outside of the modern floodplain. This map is not a floodplain hazard map or delineation of actual flood boundaries. Although wetlands are included in the Classification, they are based on different criteria than jurisdictional wetlands. The extent of mapping may differ from the actual limit of tidal influence.

Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith Marcoe

2012-01-01

323

LAX and SPA: Major regulators of shoot branching in rice  

Microsoft Academic Search

The aerial architecture of plants is determined primarily by the pattern of shoot branching. Although shoot apical meristem initiation during embryogenesis has been extensively studied by molecular genetic approaches using Arabidopsis, little is known about the genetic mechanisms controlling axillary meristem initiation, mainly because of the insufficient number of mutants that specifically alter it. We identified the LAX PANICLE (LAX)

Keishi Komatsu; Masahiko Maekawa; Shin Ujiie; Yuzuki Satake; Ikuyo Furutani; Hironobu Okamoto; Ko Shimamoto; Junko Kyozuka

2003-01-01

324

Major Programs  

Cancer.gov

The Division of Cancer Prevention supports major scientific collaborations and research networks at more than100 sites across the United States; investigator-initiated grants; postdoctoral training; and specialized resources for researchers.

325

21 CFR 137.350 - Enriched rice.  

Code of Federal Regulations, 2010 CFR

(a) The foods for which definitions and standards of identity are prescribed by this section are forms of milled rice (except rice coated with talc and glucose and known as coated rice), to which nutrients have been added so that each pound of the rice contains: (1) Not less than...

2010-04-01

326

Association of Alcaligenes faecalis with wetland rice  

Microsoft Academic Search

Alcaligenes faecalis isolated from rice roots is widespread in paddy soil of China. It was found to be a close association with rice.A. faecalis accumulate on the rice root surface, and part of them could enter into the rice root. It can grow in the intercellular space, especially inside the root cells, and multiply and fix dinitrogen there.A. faecalis could

C. B. You; W. Song; H. X. Wang; J. P. Li; M. Lin; W. L. Hai

1991-01-01

327

QUALITY CHARACTERIZATION OF CALIFORNIA PUBLIC RICE VARIETIES  

Technology Transfer Automated Retrieval System (TEKTRAN)

A set of 14 rice varieties were grown at the Rice Experiment Station (RES) in2000 and analyzed under a battery of physicochemical tests. The tests, indicators of cooking and processing characteristics, were conducted by the Rice End-Use Quality Research Laboratory at the USDA-ARS-Rice Research Unit...

328

Protein requirements of preschool children consuming rice-milk, rice-toasted mung bean, and rice diets  

Microsoft Academic Search

Rice-milk and rice-toasted mung bean diets, and a high-protein rice (IR58 milled rice) were evaluated as part of a study on the protein requirements of toddlers consuming rice-based diets following the multilevel N balance method. Milk or mung bean contributed 1\\/3 of dietary N. At a daily energy intake of 418 kJ\\/kg body weight, weight losses were observed for all

Maria A. Isabel Cabrera-Santiago; Carmen L. L. Intengan; Benigan V. Roxas; Bienvenido O. Juliano; Consuelo M. Perez; Anacleta S. Loyola; Emma R. Alejandro; Jovina N. Abadilla; Gracia FE B. Yu; Aida C. Mallillin

1986-01-01

329

Formation and emission of methane in rice soils: Experimental determination and modeling analysis. Final report  

SciTech Connect

Rice paddy soils have been identified as a major source of methane emissions contributing to the observed atmospheric increase in methane. This points to the need for a method of quantifying and predicting methane emissions for the widely varying conditions used in rice agriculture throughout the world. In the present work, a mathematical model for estimating the emission of methane from rice paddy soils is developed and refined. Kinetic parameters for methanogenesis in a Louisiana rice soil are determined from laboratory data on methane production from acetic acid substrate. Use of a stirred reactor allows simultaneous measurement of acetate consumption and methane production while minimizing mass transfer limitations. An existing model for rice plant growth is utilized to provide data on the availability of root exudates as a carbon source for the methanogens. The final methane model includes the kinetic parameters, plant data, and estimated transport parameters. With adjustments in these parameters, it provides an acceptable match to field data.

Law, V.J.; Bhattacharya, S.K.

1993-08-31

330

Isolation and identification of DPPH radical scavenging compounds in Kurosu (Japanese unpolished rice vinegar).  

PubMed

Dihydroferulic acid (DFA) and dihydrosinapic acid (DSA) were isolated from Kurosu (unpolished rice vinegar) as the major constituents responsible for Kurosu's radical scavenging activity. The levels of antioxidative activity of DFA and DSA in DPPH radical scavenging were higher than those of their respective structurally related compounds, ferulic acid and sinapic acid. The concentrations of DFA and DSA were low in common rice vinegar (polished rice vinegar), suggesting that Kurosu is more advantageous than rice vinegars as an antioxidative food item. As the concentrations of DFA and DSA were low in unpolished rice, too, these acids are thought to be produced in Kurosu through the process of the fermentation from ferulic acid and sinapic acid, respectively. PMID:12381140

Shimoji, Yumi; Tamura, Yoshitaka; Nakamura, Yoshimasa; Nanda, Kumiko; Nishidai, Shoko; Nishikawa, Yasushi; Ishihara, Nobuhiro; Uenakai, Kazuo; Ohigashi, Hajime

2002-10-23

331

Genomewide SNP variation reveals relationships among landraces and modern varieties of rice  

PubMed Central

Rice, the primary source of dietary calories for half of humanity, is the first crop plant for which a high-quality reference genome sequence from a single variety was produced. We used resequencing microarrays to interrogate 100 Mb of the unique fraction of the reference genome for 20 diverse varieties and landraces that capture the impressive genotypic and phenotypic diversity of domesticated rice. Here, we report the distribution of 160,000 nonredundant SNPs. Introgression patterns of shared SNPs revealed the breeding history and relationships among the 20 varieties; some introgressed regions are associated with agronomic traits that mark major milestones in rice improvement. These comprehensive SNP data provide a foundation for deep exploration of rice diversity and gene–trait relationships and their use for future rice improvement.

McNally, Kenneth L.; Childs, Kevin L.; Bohnert, Regina; Davidson, Rebecca M.; Zhao, Keyan; Ulat, Victor J.; Zeller, Georg; Clark, Richard M.; Hoen, Douglas R.; Bureau, Thomas E.; Stokowski, Renee; Ballinger, Dennis G.; Frazer, Kelly A.; Cox, David R.; Padhukasahasram, Badri; Bustamante, Carlos D.; Weigel, Detlef; Mackill, David J.; Bruskiewich, Richard M.; Ratsch, Gunnar; Buell, C. Robin; Leung, Hei; Leach, Jan E.

2009-01-01

332

Energy flow in an arctic aquatic ecosystem  

SciTech Connect

Natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. Our overall goals are to a determine if carbon is accumulating in upland and coastal tundra; determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers. Past work on fishes, birds, and the prey species of insects and aquatic crustaceans has shown that peat carbon is very important in the energy supply supporting the food webs over the course of the year. Obligate freshwater fishes from the coastal lakes and Colville River have been shown to contain up to 60 percent peat carbon at the end of the winter season. In contrast, migratory shorebirds and passerines contained much smaller radiocarbon abundances in summer, indicating a major shift to recent in situ primary production in pond and stream ecosystems in summer months. For the past two years, we have narrowed our focus to the processes supplying carbon to the beaded stream system at MS-117 and have concentrated on determining the transfer and accumulation rates of carbon in the watershed.

Schell, D.M.

1988-01-01

333

Energy flow in an arctic aquatic ecosystem  

SciTech Connect

Natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. Our overall goals are to a determine if carbon is accumulating in upland and coastal tundra; determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers. Past work on fishes, birds, and the prey species of insects and aquatic crustaceans has shown that peat carbon is very important in the energy supply supporting the food webs over the course of the year. Obligate freshwater fishes from the coastal lakes and Colville River have been shown to contain up to 60 percent peat carbon at the end of the winter season. In contrast, migratory shorebirds and passerines contained much smaller radiocarbon abundances in summer, indicating a major shift to recent in situ primary production in pond and stream ecosystems in summer months. For the past two years, we have narrowed our focus to the processes supplying carbon to the beaded stream system at MS-117 and have concentrated on determining the transfer and accumulation rates of carbon in the watershed.

Schell, D.M.

1988-12-31

334

Remotely Sensed Rice Yield Prediction Using Multi-Temporal NDVI Data Derived from NOAA's-AVHRR  

PubMed Central

Grain-yield prediction using remotely sensed data have been intensively studied in wheat and maize, but such information is limited in rice, barley, oats and soybeans. The present study proposes a new framework for rice-yield prediction, which eliminates the influence of the technology development, fertilizer application, and management improvement and can be used for the development and implementation of provincial rice-yield predictions. The technique requires the collection of remotely sensed data over an adequate time frame and a corresponding record of the region's crop yields. Longer normalized-difference-vegetation-index (NDVI) time series are preferable to shorter ones for the purposes of rice-yield prediction because the well-contrasted seasons in a longer time series provide the opportunity to build regression models with a wide application range. A regression analysis of the yield versus the year indicated an annual gain in the rice yield of 50 to 128 kg ha?1. Stepwise regression models for the remotely sensed rice-yield predictions have been developed for five typical rice-growing provinces in China. The prediction models for the remotely sensed rice yield indicated that the influences of the NDVIs on the rice yield were always positive. The association between the predicted and observed rice yields was highly significant without obvious outliers from 1982 to 2004. Independent validation found that the overall relative error is approximately 5.82%, and a majority of the relative errors were less than 5% in 2005 and 2006, depending on the study area. The proposed models can be used in an operational context to predict rice yields at the provincial level in China. The methodologies described in the present paper can be applied to any crop for which a sufficient time series of NDVI data and the corresponding historical yield information are available, as long as the historical yield increases significantly.

Huang, Jingfeng; Wang, Xiuzhen; Li, Xinxing; Tian, Hanqin; Pan, Zhuokun

2013-01-01

335

Arsenic in Rice: Full Analytical Results from Rice/Rice Product ...  

Center for Food Safety and Applied Nutrition (CFSAN)

... 721856A, Rice (non-Basmati), Whole Grain Red, USA, 126, 88, 26, 0, 4.0. ... 719997B, Rice Cakes, Apple Cinnamon, NR, 263, 171, 127, TR, 5.1. ... More results from www.fda.gov/food/foodborneillnesscontaminants/metals

336

Natural ecosystem design and control imperatives for sustainable ecosystem services  

Microsoft Academic Search

Sustainability of ecosystem services to humanity will depend on knowledge of how ecosystems work in their natural states, which can then be carried over to managed states. The objective of this paper is to describe four properties of ecosystems taken as natural conditions to be maintained under exploitation. Three of these are design properties: near-steady-state or extremal dynamics, dominance of

Bernard C. Patten

2010-01-01

337

Golden rice: introgression, breeding, and field evaluation  

Microsoft Academic Search

Considerable progress has been made on the genetic engineering of rice for improved nutritional content involving micronutrients\\u000a and carotenoid content. Golden Rice, developed by genetic engineering (Agrobacterium and biolistic transformation) was used in rice breeding for the transfer of high-nutritional value to the local rice cultivars.\\u000a Simultaneously, commercial Asian indica rice cultivars were also developed with expression of high-carotenoid levels.

Swapan K. Datta; Karabi Datta; Vilas Parkhi; Mayank Rai; Niranjan Baisakh; Gayatri Sahoo; Sayeda Rehana; Anindya Bandyopadhyay; Editha Abrigo; Norman Oliva; Lina Torrizo

2007-01-01

338

BIOGEOCHEMICAL INDICATORS IN AQUATIC ECOSYSTEMS  

EPA Science Inventory

Loadings of excess organic wastes and associated nutrients to aquatic systems has numerous deleterious consequences with respect to the ecosystem services provided by these important ecosystems including perturbation of organic matter and nutrient cycling rates, reduction in diss...

339

Ecosystem Restoration Research at GWERD  

EPA Science Inventory

Ground Water and Ecosystems Restoration Division, Ada, OK Mission: Conduct research and technical assistance to provide the scientific basis to support the development of strategies and technologies to protect and restore ground water, surface water, and ecosystems impacted b...

340

Rice crop duration and leaf appearance rate in a variable thermal environment. III. Heritability of photothermal traits  

Microsoft Academic Search

In arid, irrigated, rice environments, crop duration is highly variable, resulting in uncertain crop calendars for double cropping. The main causes of this variability are varying temperature and daylength. Breeding for stable crop duration in such environments might make a major contribution to rice production. A previous study established genetic differences in phenological responses to temperature and photoperiod, based on

M Sié; M Dingkuhn; M. C. S Wopereis; K. M Miezan

1998-01-01

341

Efficacy of bacillus biocontrol agents for management of sheath blight and narrow brown leaf spot in organic rice  

Technology Transfer Automated Retrieval System (TEKTRAN)

Organic rice production has significantly increased in the U. S. over the last decade. Growers lack effective tools to manage sheath blight, caused by Rhizoctonia solani, and narrow brown leaf spot (NBLS), caused by Cercospora janseana, two major diseases affecting organic rice production. An experi...

342

Seeing red: the origin of grain pigmentation in US weedy rice.  

PubMed

Weedy forms of crop species infest agricultural fields worldwide and are a leading cause of crop losses, yet little is known about how these weeds evolve. Red rice (Oryza sativa), a major weed of cultivated rice fields in the US, is recognized by the dark-pigmented grain that gives it its common name. Studies using neutral molecular markers have indicated a close relationship between US red rice and domesticated rice, suggesting that the weed may have originated through reversion of domesticated rice to a feral form. We have tested this reversion hypothesis by examining molecular variation at Rc, the regulatory gene responsible for grain pigmentation differences between domesticated and wild rice. Loss-of-function mutations at Rc account for the absence of proanthocyanidin pigments in cultivated rice grains, and the major rc domestication allele has been shown to be capable of spontaneous reversion to a functional form through additional mutations at the Rc locus. Using a diverse sample of 156 weedy, domesticated and wild Oryzas, we analysed DNA sequence variation at Rc and its surrounding 4 Mb genomic region. We find that reversion of domestication alleles does not account for the pigmented grains of weed accessions; moreover, we find that haplotypes characterizing the weed are either absent or very rare in cultivated rice. Sequences from genomic regions flanking Rc are consistent with a genomic footprint of the rc selective sweep in cultivated rice, and they are compatible with a close relationship of red rice to Asian Oryzas that have never been cultivated in the US. PMID:20584133

Gross, Briana L; Reagon, Michael; Hsu, Shih-Chung; Caicedo, Ana L; Jia, Yulin; Olsen, Kenneth M

2010-06-24

343

One Grain of Rice  

NSDL National Science Digital Library

Beginning with the famous story of the village girl trying to feed her people, the lesson involves students in the mathematics of exponential growth. Students work collaboratively to come up with a bargaining plan to trick a raja into feeding the village using algebra and estimation. The complete activity includes the development of an exponential equation, but just following the growth of the number of rice grains throughout the story gives a good introduction to exponential growth. Questions for students and ideas for assessment are provided.

Simon, Christy

2000-01-01

344

Biocomplexity in mangrove ecosystems.  

PubMed

Mangroves are an ecological assemblage of trees and shrubs adapted to grow in intertidal environments along tropical coasts. Despite repeated demonstration of their economic and societal value, more than 50% of the world's mangroves have been destroyed, 35% in the past two decades to aquaculture and coastal development, altered hydrology, sea-level rise, and nutrient overenrichment. Variations in the structure and function of mangrove ecosystems have generally been described solely on the basis of a hierarchical classification of the physical characteristics of the intertidal environment, including climate, geomorphology, topography, and hydrology. Here, we use the concept of emergent properties at multiple levels within a hierarchical framework to review how the interplay between specialized adaptations and extreme trait plasticity that characterizes mangroves and intertidal environments gives rise to the biocomplexity that distinguishes mangrove ecosystems. The traits that allow mangroves to tolerate variable salinity, flooding, and nutrient availability influence ecosystem processes and ultimately the services they provide. We conclude that an integrated research strategy using emergent properties in empirical and theoretical studies provides a holistic approach for understanding and managing mangrove ecosystems. PMID:21141670

Feller, I C; Lovelock, C E; Berger, U; McKee, K L; Joye, S B; Ball, M C

2010-01-01

345

Thermodynamic stability of ecosystems  

Microsoft Academic Search

The stability of ecosystems during periods of stasis in their macro-evolutionary trajectory is studied from a non-equilibrium thermodynamic perspective. Individuals of the species are considered as units of entropy production and entropy exchange in an open thermodynamic system. Within the framework of the classical theory of irreversible thermodynamics, and under the condition of constant external constraints, such a system will

K. Michaelian

2005-01-01

346

Valuing Ecosystem Services  

Microsoft Academic Search

The value of the services provided top human societies by natural ecosystems and biogeochemical cycles has recently been the topic of discussion and research. Here I review some of the basic economic principles necessary for understanding some of the questions that arise in this area. I argue that even with the best possible data and scientific understanding, the sense in

Geoffrey M. Heal

2001-01-01

347

Limiting Factors in Ecosystems  

NSDL National Science Digital Library

The purpose of this resource is to understand that physical factors - temperature and precipitation - limit the growth of vegetative ecosystems. Students observe and record seasonal changes in their local study site. They establish that these phenomena follow annual cycles and conclude the activity by creating displays that illustrate the repeating pattern associated with the appearance and disappearance of seasonal markers.

The GLOBE Program, University Corporation for Atmospheric Research (UCAR)

2003-08-01

348

Ecosystem Services: A Primer  

NSDL National Science Digital Library

The issue-focused reprint explains how natural ecosystems produce services upon which we are dependent. For example, they: provide us with clean water and air, pollinate our crops and disperse seeds, protect us from extreme weather and ultraviolet light, and control pests and disease-carrying organisms.

Ecological Society of America (;)

2000-06-01

349

Boston Harbor Ecosystems  

NSDL National Science Digital Library

This United States Geological Survey (USGS) site is designed to summarize and make available results of scientific research conducted in Boston Harbor, Massachusetts since 1985. A computer image of the harbor indicates ecosystem zones with descriptions (watershed, estuary, inner shelf, and basin), sewage outfall sites, and rock types. Links are provided for more information on this region.

350

Methane emission from fields with three various rice straw treatments in Taiwan paddy soils.  

PubMed

Flooded rice fields are one of the major biogenic methane sources. In this study, the effects of straw residual treatments on methane emission from paddy fields were discussed. The experimental field was located at Tainan District Agricultural Improvement Station in Chia-Yi county (23 degrees 25'08''N, 120degrees16'26''E) of southern Taiwan throughout the first and the second crop seasons in 2000. The seasonal methane fluxes in the first crop season with rice stubble removed, rice straw burned and rice straw incorporated were 4.41, 3.78 and 5.27 g CH4 m(-2), and the values were 32.8, 38.9 and 75.1 g CH4 m(-2) in the second crop season, respectively. In comparison of three management methods of rice straw residue, the incorporation of rice straw residue should show a significant tendency for enhancing methane emission in the second crop season. Moreover, stubble removed and straw burned treatments significantly reduced CH4 emissions by 28 approximately 56% emissions compared to straw incorporated plot. Concerning for air quality had led to legislation restricting rice straw burning, removing of rice stubble might be an appropriate methane mitigation strategy in Taiwan paddy soils. PMID:12856932

Liou, Rey-May; Huang, Shan-Ney; Lin, Chin-Wei; Chen, Shin-Hsiung

2003-07-01

351

Comparative analyses reveal high levels of conserved colinearity between the finger millet and rice genomes.  

PubMed

Finger millet is an allotetraploid (2n = 4x = 36) grass that belongs to the Chloridoideae subfamily. A comparative analysis has been carried out to determine the relationship of the finger millet genome with that of rice. Six of the nine finger millet homoeologous groups corresponded to a single rice chromosome each. Each of the remaining three finger millet groups were orthologous to two rice chromosomes, and in all the three cases one rice chromosome was inserted into the centromeric region of a second rice chromosome to give the finger millet chromosomal configuration. All observed rearrangements were, among the grasses, unique to finger millet and, possibly, the Chloridoideae subfamily. Gene orders between rice and finger millet were highly conserved, with rearrangements being limited largely to single marker transpositions and small putative inversions encompassing at most three markers. Only some 10% of markers mapped to non-syntenic positions in rice and finger millet and the majority of these were located in the distal 14% of chromosome arms, supporting a possible correlation between recombination and sequence evolution as has previously been observed in wheat. A comparison of the organization of finger millet, Panicoideae and Pooideae genomes relative to rice allowed us to infer putative ancestral chromosome configurations in the grasses. PMID:17619853

Srinivasachary; Dida, Mathews M; Gale, Mike D; Devos, Katrien M

2007-07-10

352

Field response of aboveground non-target arthropod community to transgenic Bt-Cry1Ab rice plant residues in postharvest seasons.  

PubMed

Risk assessments of ecological effects of transgenic rice expressing lepidoptera-Cry proteins from Bacillus thuringiensis (Bt) on non-target arthropods have primarily focused on rice plants during cropping season, whereas few studies have investigated the effects in postharvest periods. Harvested rice fallow fields provide a critical over-wintering habitat for arthropods in the Chinese rice ecosystems, particularly in the southern region of the country. During 2006-08, two independent field trials were conducted in Chongqing, China to investigate the effects of transgenic Cry1Ab rice residues on non-target arthropod communities. In each trial, pitfall traps were used to sample arthropods in field plots planted with one non-Bt variety and two Bt rice lines expressing the Cry1Ab protein. Aboveground arthropods in the trial plots during the postharvest season were abundant, while community densities varied significantly between the two trials. A total of 52,386 individual insects and spiders, representing 93 families, was captured in the two trials. Predominant arthropods sampled were detritivores, which accounted for 91.9% of the total captures. Other arthropods sampled included predators (4.2%), herbivores (3.2%), and parasitoids (0.7%). In general, there were no significant differences among non-Bt and Bt rice plots in all arthropod community-specific parameters for both trials, suggesting no adverse impact of the Bt rice plant residues on the aboveground non-target arthropod communities during the postharvest season. The results of this study provide additional evidence that Bt rice is safe to non-target arthropod communities in the Chinese rice ecosystems. PMID:22252123

Bai, Yao-Yu; Yan, Rui-Hong; Ye, Gong-Yin; Huang, Fangneng; Wangila, David S; Wang, Jin-Jun; Cheng, Jia-An

2012-01-18

353

Machine Learning in Ecosystem Informatics  

Microsoft Academic Search

The emerging eld of Ecosystem Informatics applies meth- ods from computer science and mathematics to address fundamental and applied problems in the ecosystem sciences. The ecosystem sciences are in the midst of a revolution driven by a combination of emerging tech- nologies for improved sensing and the critical need for better science to help manage global climate change. This paper

Thomas G. Dietterich

2007-01-01

354

Ecosystems in the Learning Environment  

ERIC Educational Resources Information Center

|Habitats, ecology and evolution are a few of the many metaphors commonly associated with the domain of biological ecosystems. Surprisingly, these and other similar biological metaphors are proving to be equally associated with a phenomenon known as digital ecosystems. Digital ecosystems make a direct connection between biological properties and…

Louviere, Gregory

2011-01-01

355

Investigating Ecosystems in a Biobottle  

ERIC Educational Resources Information Center

|Biobottles are miniature ecosystems made from 2-liter plastic soda bottles. They allow students to explore how organisms in an ecosystem are connected to each other, examine how biotic and abiotic factors influence plant and animal growth and development, and discover how important biodiversity is to an ecosystem. This activity was inspired by an…

Breene, Arnica; Gilewski, Donna

2008-01-01

356

International Year of Rice 2004  

NSDL National Science Digital Library

The importance of rice as a basic foodstuff to over half of the world's populations can not be underestimated, and it was with this fact in mind that the International Rice Research Institute first developed the idea for the International Year of Rice in 1999. Working in tandem with the United Nations General Assembly, the Institute set up a number of partnerships, conferences, lectures, and research agendas to take place throughout the year 2004 and beyond. The site contains links to numerous important papers, such as the collection available here from the recent conference titled Rice in Global Markets and Sustainable Production Systems, which was held in Rome. Beyond various scholarly and policy-oriented resources, visitors can learn about the rice photography contest, submit recipes to a forthcoming rice-themed cookbook, and explore a kids section that offers some basic facts about rice, along with a short quiz. The site is available in a number of different languages, including Italian, Spanish, French, Arabic, and Japanese.

357

Effects of water management, connectivity, and surrounding land use on habitat use by frogs in rice paddies in Japan.  

PubMed

In Japan, rice paddies play an important role as a substitute habitat for wetland species, and support rich indigenous ecosystems. However, since the 1950s, agricultural modernization has altered the rice paddy environment, and many previously common species are now endangered. It is urgently necessary to evaluate rice paddies as habitats for conservation. Among the species living in rice paddies, frogs are representative and are good indicator species, so we focused on frog species and analyzed the influence of environmental factors on their habitat use. We found four frog species and one subspecies (Hyla japonica, Pelophylax nigromaculatus, Glandirana rugosa, Lithobates catesbeianus, and Pelophylax porosa brevipoda) at our study sites in Shiga prefecture. For all but L. catesbeianus, we analyzed the influence of environmental factors related to rice paddy structure, water management and availability, agrochemical use, connectivity, and land use on breeding and non-breeding habitat use. We constructed generalized additive mixed models with survey date as the smooth term and applied Akaike's information criterion to choose the bestranked model. Because life histories and biological characteristics vary among species, the factors affecting habitat use by frogs are also expected to differ by species. We found that both breeding and non-breeding habitat uses of each studied species were influenced by different combinations of environmental factors and that in most cases, habitat use showed seasonality. For frog conservation in rice paddies, we need to choose favorable rice paddy in relation to surrounding land use and apply suitable management for target species. PMID:22943781

Naito, Risa; Yamasaki, Michimasa; Lmanishi, Ayumi; Natuhara, Yosihiro; Morimoto, Yukihiro

2012-09-01

358

Soil microbial biomass as affected by non-flooded plastic mulching cultivation in rice  

Microsoft Academic Search

The long-term field experiments were initiated in 2001 on five sites in Zhejiang province of China to monitor the impacts of non-flooded plastic mulching management on rice soil microbial biomass for sustainable agro-ecosystem. The three treatments were plastic film mulching with no flooding (PM), no plastic film mulching and no flooding (UM), and the traditional flooding management (TF). Microbial biomass

Yong-Shan Li; Liang-Huan Wu; Xing-Hua Lu; Li-Mei Zhao; Qiao-Lan Fan; Fu-Suo Zhang

2006-01-01

359

Contribution of plant photosynthates to dissolved organic carbon in a flooded rice soil  

Microsoft Academic Search

Dissolved organic C (DOC) plays important roles in nutrient cycling and methane production in flooded rice ecosystem. The microcosm experiment was carried out to measure directly the contribution of photosynthates to DOC by using a 13C pulse-chase labeling technique. DOC was operationally divided into water-extractable organic C (WEOC) and salt-extractable organic C (SEOC) by successive extraction firstly with deionized water

Yahai Lu; Akira Watanabe; Makoto Kimura

2005-01-01

360

40 CFR Table 2b to Subpart Zzzz of... - Operating Limitations for New and Reconstructed 2SLB and CI Stationary RICE >500 HP Located at a...  

Code of Federal Regulations, 2013 CFR

...Stationary RICE >500 HP Located at a Major Source of HAP Emissions, New and Reconstructed...Stationary RICE â¥250 HP Located at a Major Source of HAP Emissions, Existing CI Stationary...STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED)...

2013-07-01

361

Terrestrial ecosystem responses to global change: A research strategy  

SciTech Connect

Uncertainty about the magnitude of global change effects on terrestrial ecosystems and consequent feedbacks to the atmosphere impedes sound policy planning at regional, national, and global scales. A strategy to reduce these uncertainties must include a substantial increase in funding for large-scale ecosystem experiments and a careful prioritization of research efforts. Prioritization criteria should be based on the magnitude of potential changes in environmental properties of concern to society, including productivity; biodiversity; the storage and cycling of carbon, water, and nutrients; and sensitivity of specific ecosystems to environmental change. A research strategy is proposed that builds on existing knowledge of ecosystem responses to global change by (1) expanding the spatial and temporal scale of experimental ecosystem manipulations to include processes known to occur at large scales and over long time periods; (2) quantifying poorly understood linkages among processes through the use of experiments that manipulate multiple interacting environmental factors over a broader range of relevant conditions than did past experiments; and (3) prioritizing ecosystems for major experimental manipulations on the basis of potential positive and negative impacts on ecosystem properties and processes of intrinsic and/or utilitarian value to humans and on feedbacks of terrestrial ecosystems to the atmosphere.

NONE

1998-09-01

362

Drought tolerance genes in rice.  

PubMed

Quantitative trait loci (QTLs) for drought tolerance (DT) can be readily identified in available databases and in this paper, these QTLs were summarized in the form of a consensus map. An in silico strategy was then deployed to mine for candidate genes associated with DT QTLs using rice dbEST and rice genome databases. DT QTLs on rice chromosomes 1, 2, 4, 8, and 9 were selected to test the method. The result showed candidate genes associated with DT could be readily identified. PMID:16552602

Zeng, Huazong; Zhong, Yang; Luo, Lijun

2006-03-22

363

7 CFR 868.310 - Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice...  

Code of Federal Regulations, 2013 CFR

...the classes Long Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled...Section 868.310 Agriculture Regulations of the Department of Agriculture...classes Long Grain Milled Rice, Medium Grain Milled Rice, Short Grain...

2013-01-01

364

Seasonality of ecosystem respiration in a double-cropping paddy field in Bangladesh  

NASA Astrophysics Data System (ADS)

Ecosystem respiration (RE) from cultivated ecosystems is important for understanding the role of these ecosystems in the global carbon balance. To evaluate carbon dynamics in a double-rice cropping paddy field, we conducted long-term measurements at Mymensingh, Bangladesh in 2007 using a tower-based eddy covariance technique. The study objectives were to investigate the diurnal and seasonal variations in RE and to develop and evaluate empirical models for predicting variations in RE using environmental parameters. We found that the diurnal pattern of RE was driven by soil temperature (Ts) whereas the seasonal variation in RE was controlled primarily by Ts and soil water content (SWC). Under high biomass conditions, Ts plays a dominant role in the magnitude of CO2 release. Both the amount and magnitude of RE variation were larger in the "Boro" dry-season rice growing period from late winter to mid-summer than in the "Aman" wet-season rice growing period from late summer to early winter. Annually, the ratio of RE to gross primary production (GPP) was 0.67, indicating a net sink of carbon; the two growing seasons had RE/GPP ratios of 0.58 and 0.52. A model using Ts, SWC, and aboveground biomass predicted daily RE with R2 values of 0.87 and 0.62 for the Boro and Aman seasons, respectively.

Hossen, M. S.; Mano, M.; Miyata, A.; Baten, M. A.; Hiyama, T.

2011-08-01

365

Continental Margins: Linking Ecosystems  

NASA Astrophysics Data System (ADS)

Impacts of Global, Local and Human Forcings on Biogeochemical Cycles and Ecosystems, IMBER/LOICZ Continental Margins Open Science Conference; Shanghai, China, 17-21 September 2007; More than 100 scientists from 25 countries came together to address global, regional, local, and human pressures interactively affecting continental margin biogeochemical cycles, marine food webs, and society. Continental margins cover only 12% of the global ocean area yet account for more than 30% of global oceanic primary production. In addition, continental margins are the most intensely used regions of the world's ocean for natural commodities, including productive fisheries and mineral and petroleum resources. The land adjacent to continental margins hosts about 50% of the world's population, which will bear many direct impacts of global change on coastal margins. Understanding both natural and human-influenced alterations of biogeochemical cycles and ecosystems on continental margins and the processes (including feedbacks) that threaten sustainability of these systems is therefore of global interest.

Kelly-Gerreyn, Boris; Rabalais, Nancy; Middelburg, Jack; Roy, Sylvie; Liu, Kon-Kee; Thomas, Helmuth; Zhang, Jing

2008-02-01

366

The Ecosystem Services Framework and Natural Capital Conservation  

Microsoft Academic Search

Work at the interface of ecology and economics has inspired a major transformation in the way people think about the environment.\\u000a Increasingly, ecosystems are seen as capital assets, with the potential to generate a stream of vital life-support services\\u000a meriting careful evaluation and investment. We first present the concepts underpinning the ecosystem services framework (ESF),\\u000a laying out the scope and

R. K. Turner; G. C. Daily

2008-01-01

367

A Method for Assessing Hydrologic Alteration within Ecosystems  

Microsoft Academic Search

Abstract: Hydrologic regimes play a major role in determining the biotic composition, structure, and function of aquatic, wetland, and riparian ecosystems. However, human land and water uses are substantially altering hydrologic regimes around the world. Improved quantitative evaluations of human-inducedhydrologic changes,are needed,to advance research on the biotic implications of hydrologic alteration, and to support ecosystem,management,and restoration plans. To facilitate such

Brian D. Richter; Jeffrey V. Baumgartner; Jennifer Powell; David P. Braun

1996-01-01

368

Development of casparian strip in rice cultivars  

PubMed Central

The development of Casparian strips (CSs) on the endo- and exodermis and their chemical components in roots of three cultivars of rice (Oryza sativa) with different salt tolerance were compared using histochemistry and Fourier transform infrared (FTIR) spectroscopy. The development and deposition of suberin lamellae of CSs on the endo- and exodermis in the salt-tolerant cultivar Liaohan 109 was earlier than in the moderately tolerant cultivar Tianfeng 202 and the sensitive cultivar Nipponbare. The detection of chemical components indicated major contributions to the structure of the outer part from aliphatic suberin, lignin and cell wall proteins and carbohydrates to the rhizodermis, exodermis, sclerenchyma and one layer of cortical cells in series (OPR) and the endodermal Casparian strip. Moreover, the amounts of these major chemical components in the outer part of the Liaohan 109 root were higher than in Tianfeng 202 and Nipponbare, but there was no distinct difference in endodermal CSs among the three rice cultivars. The results suggest that the exodermis of the salt-tolerant cultivar Liaohan 109 functions as a barrier for resisting salt stress.

Cai, Xia; Chen, Tong; Zhou, QingYuan; Xu, Lei; Qu, LeQing; Hua, XueJun

2011-01-01

369

Western Hemlock Ecosystem  

Microsoft Academic Search

We report measurements of rates of sap flow in dominant trees, changes in soil moisture, and evaporation from coarse woody debris in an old- growth Douglas-fir-western hemlock ecosystem at Wind River, Washington, USA, during dry periods in summer. The measurements are compared with eddy-covariance measurements of water-vapor fluxes above the forest (Ee) and at the forest floor (Eu) to examine

Michael H. Unsworth; Kyaw Tha

370

Recovery in complex ecosystems  

Microsoft Academic Search

Current ecosystem theory has a deceptively simple representation of recovery. In actual practice,recovery is affected by the\\u000a frequency and extent of disturbances and by the spatial heterogeneity of the ecological system. Environmental changes may\\u000a pass through thresholds causing recovery to a different plant and animal community. The sheer complexity of the system combined\\u000a with unanticipated synergistic effects can make recovery

Robert V. O‘Neill

1998-01-01

371

Application of a terrestrial ecosystem model to assess ecosystem services in Asia  

NASA Astrophysics Data System (ADS)

Net primary production (NPP) is a measure of the production rate of organic matter and the gross rate of carbon fixation. NPP is considered as appropriate concept for analyzing variations of the ecosystems induced by land use. Human appropriation of net primary production (HANPP) is a major indicator of human pressures on ecosystems. Land use induced changes in the productivity affect the processes and functions of ecosystems and they are associated with the provision of ecosystem services, such as the provision of biomass through agriculture and forestry, and the regulation services such as the absorption capacity for GHG emissions. A number of studies have been assessed the amount of human induced changes of NPP in the global level and calculated in spatially explicit way. However, the analysis of socio-economic drivers of the changes is still remaining as the main topic in the field. The interrelations between HANPP and social structures and processes are priority of global change research. The methodologies for credible HANPP assessment have been established in the previous studies. The proposed three parameters are (1)NPPptn: NPP of the vegetation that would be assumed to prevail in the absence of human use (potential vegetation), (2)NPPact: NPP of the currently prevailing vegetation (actual vegetation), (3)NPPh: human harvest of NPP (e.g., through agriculture and forestry). We estimated these parameters in Asia using a process-based ecosystem model that describes carbon and nitrogen dynamics of plants and soils for terrestrial ecosystems of the globe. The socio-economic data on crop and timber harvest was applied to estimate the amount of human harvest of NPP. The parameters were calculated for each political unit to discuss social structures responding to various ecosystems. Based on the estimated parameters, we suggest the effective methodology combining spatially explicit gridded data and socio-economic statistical data.

Shoyama, K.; Yamagata, Y.; Ito, A.; Kohyama, T.

2011-12-01

372

Genetic Diversity and Population Structure of Rice Pathogen Ustilaginoidea virens in China  

PubMed Central

Rice false smut caused by the fungal pathogen Ustilaginoideavirens is becoming a destructive disease throughout major rice-growing countries. Information about its genetic diversity and population structure is essential for rice breeding and efficient control of the disease. This study compared the genome sequences of two U. virens isolates. Three SNP-rich genomic regions were identified as molecular markers that could be used to analyze the genetic diversity and population structure of U. virens in China. A total of 56 multilocus sequence types (haplotypes) were identified out of 162 representative isolates from 15 provinces covering five major rice-growing areas in China. However, the phylogeny, based on sequences at individual SNP-rich regions, strongly conflicted with each other and there were significant genetic differences between different geographical populations. Gene flow between the different geographical populations and genetic differentiation within each geographical population were also detected. In addition, genetic recombination and genetic isolation resulting from geographic separation was also found.

Tan, Xinqiu; Yu, Yufei; He, Haiyong; Zhang, Xinyu; Liu, Yongfeng; Wang, Shu; Sun, Wenxian; Cai, Lei; Li, Shaojie

2013-01-01

373

Interactions among rice ORC subunits.  

PubMed

The origin recognition complex (ORC) is composed of six subunits and plays an important role in DNA replication in all eukaryotes. The ORC subunits OsORC6 as well as the other five ORC subunits in rice were experimentally isolated and sequenced. It indicated that there also exist six ORC subunits in rice. Results of RT-PCR indicated that expression of all the rice ORC genes are no significant difference under 26°C and 34°C. Yeast two hybridization indicated that OsORC2, -3, -5 interact with each other. OsORC5 can then bind OsORC4 to form the OsORC2, -3,-4,-5 core complex. It suggested that the basic interactions have been conserved through evolution. No binding of OsORC1 and OsORC6 with the other subunits were observed. A model of ORC complex in rice is proposed. PMID:23733064

Tan, Deyong; Lv, Qundan; Chen, Xinai; Shi, Jianghua; Ren, Meiyan; Wu, Ping; Mao, Chuanzao

2013-05-17

374

Obscuring ecosystem function with application of the ecosystem services concept.  

PubMed

Conservationists commonly have framed ecological concerns in economic terms to garner political support for conservation and to increase public interest in preserving global biodiversity. Beginning in the early 1980s, conservation biologists adapted neoliberal economics to reframe ecosystem functions and related biodiversity as ecosystem services to humanity. Despite the economic success of programs such as the Catskill/Delaware watershed management plan in the United States and the creation of global carbon exchanges, today's marketplace often fails to adequately protect biodiversity. We used a Marxist critique to explain one reason for this failure and to suggest a possible, if partial, response. Reframing ecosystem functions as economic services does not address the political problem of commodification. Just as it obscures the labor of human workers, commodification obscures the importance of the biota (ecosystem workers) and related abiotic factors that contribute to ecosystem functions. This erasure of work done by ecosystems impedes public understanding of biodiversity. Odum and Odum's radical suggestion to use the language of ecosystems (i.e., emergy or energy memory) to describe economies, rather than using the language of economics (i.e., services) to describe ecosystems, reverses this erasure of the ecosystem worker. Considering the current dominance of economic forces, however, implementing such solutions would require social changes similar in magnitude to those that occurred during the 1960s. Niklas Luhmann argues that such substantive, yet rapid, social change requires synergy among multiple societal function systems (i.e., economy, education, law, politics, religion, science), rather than reliance on a single social sphere, such as the economy. Explicitly presenting ecosystem services as discreet and incomplete aspects of ecosystem functions not only allows potential economic and environmental benefits associated with ecosystem services, but also enables the social and political changes required to ensure valuation of ecosystem functions and related biodiversity in ways beyond their measurement on an economic scale. PMID:19659684

Peterson, Markus J; Hall, Damon M; Feldpausch-Parker, Andrea M; Peterson, Tarla Rai

2009-07-29

375

Dynamics of computational ecosystems  

NASA Astrophysics Data System (ADS)

Recently, Huberman and Hogg [in The Ecology of Computation, edited by B. A. Huberman (North-Holland, 1988), pp. 77-115] analyzed the dynamics of resource allocation in a model of computational ecosystems which incorporated many of the features endemic to large distributed processing systems, including distributed control, asynchrony, resource contention, and cooperation among agents and the concomitant problems of incomplete knowledge and delayed information. In this paper we supplement an analysis of several simple examples of computational ecosystems with computer simulations to gain insight into the effects of time delays, cooperation, multiple resources, inhomogeneity, etc. The simulations verify Huberman and Hogg's prediction of persistent oscillations and chaos, and confirm the Ceccatto-Huberman [Proc. Natl. Acad. Sci. U.S.A. 86, 3443 (1989)] prediction of extremely long-lived metastable states in computational ecosystems. Extending the analysis to inhomogeneous systems, we show that they can be more stable than homogeneous systems because agents with different computational needs settle into different strategic niches, and that overly clever local decision-making algorithms can induce chaotic behavior.

Kephart, J. O.; Hogg, T.; Huberman, B. A.

1989-07-01

376

Molecular mapping of rice chromosomes  

Microsoft Academic Search

We report the construction of an RFLP genetic map of rice (Oryza sativa) chromosomes. The map is comprised of 135 loci corresponding to clones selected from a PstI genomic library. This molecular map covers 1,389 cM of the rice genome and exceeds the current classical maps by more than 20%. The map was generated from F2 segregation data (50 individuals)

S. R. McCouch; G. Kochert; Z. H. Yu; Z. Y. Wang; G. S. Khush; W. R. Coffman; S. D. Tanksley

1988-01-01

377

Rice Bowl Journals  

NSDL National Science Digital Library

Over the past few years, a number of online journal communities have been created on the web to facilitate group dialogue around a variety of issues. As one might surmise from its title, the Rice Bowl Journals website is aimed at primarily serving the Asian online journal community. The diarists featured on the site can be examined by ethnicity and location, and visitors may also wish to browse the journals by category. Perhaps of equal interest are the online discussion forums, which allow visitors to offer commentary on current events, campus life, and the art of online journaling. The site is rounded out by a FAQ area and a place for visitors to leave feedback.

2005-01-01

378

Rice University: Colvin Group  

NSDL National Science Digital Library

The Colvin Group at Rice University deals with the control and understanding of material properties on nanometer length scales. Some members of the group work to "develop new chemical approaches to forming uniform nanocrystals, and highly ordered porous solids" while "others focus on using these materials as tools for answering fundamental questions about nature, such as the characteristic length scales in glasses and liquids." Researchers can learn about the numerous projects undertaken by the group including understanding the superprism phenomena, the preparation of perfect nanocrystals of metal oxides, and the synthesis of quartz particles in the sub-micron to nanoscale size regime. Students and educators can find helpful tutorials describing the nanoscience field of study. The website also provides many of the group's published papers.

379

Expansins in deepwater rice internodes  

SciTech Connect

Cell walls of deepwater rice internodes undergo long-term extension (creep) when placed under tension in acidic buffers. This is indicative of the action of the cell wall-loosening protein expansion. Wall extension had a pH optimum of around 4.0 and was abolished by boiling. Acid-induced extension of boiled cell walls could be reconstituted by addition of salt-extracted rice or cucumber cell wall proteins. Cucumber expansion antibody recognized a single protein band of 24.5-kD apparent molecular mass on immunoblots of rice cell wall proteins. Expansions were partially purified by concanavalin A affinity chromatography and sulfopropyl (SP) cation-exchange chromatography. The latter yielded two peaks with extension activity (SP20 and SP29), and immunoblot analysis showed that both of these active fractions contained expansion of 24.5-kD molecular mass. The N-terminal amino acid sequence of SP20 expansion is identical to that deduced from the rice expansion cDNA Os-EXP1. The N-terminal amino acid sequence of SP29 expansion matches that deduced from the rice expansion cDNA Os-EXP2 in six of eight amino acids. Our results show that two expansions occur in the cell walls of rice internodes and that they may mediate acid-induced wall extension.

Cho, Hyung-Taeg; Kende, H. [Michigan State Univ., East Lansing, MI (United States)

1997-04-01

380

Impact of Seed Voucher System on Rice Farmers’ Welfare in Nigeria: A Randomized Control Trial Approach  

Microsoft Academic Search

This study adopted Randomized Control Trial to examine the impact of seed voucher system on farming households’ welfare in Nigeria using cross-sectional data of 600 rice farmers randomly selected from the three major rice ecologies of Nigeria. The WALD estimate reveals that the use of seed voucher increased household Per Capita Expenditure (PCE) by N14705.91. While the result of the

Bola Amoke Awotide; Taiwo Timothy Awoyemi; Aliou Diagne; Vivian E. T. Ojehomon

2012-01-01

381

Integrated rice insect pest control in the Guangdong Province of China  

Microsoft Academic Search

There are about 13 species of rice insect pests which are common and of major significance in Guangdong Province, China. Rice\\u000a pest management in China is based on cultural practices, biological control, insecticides, light traps, varietal resistance\\u000a and other control methods. Natural control by preservation of natural enemies of pests plays a very positive role in the integrated\\u000a control of

Li Li-Ying

1982-01-01

382

Priming of field-sown rice seed enhances germination, seedling establishment, allometry and yield  

Microsoft Academic Search

Poor seedling establishment is a major deterrent in adopting direct seeding of rice. Seed priming to obtain better crop stand could be an attractive approach. The objective of this study was to determine the effectiveness of seed priming strategies on the improved agronomic characters of direct-sown rice. Seed priming strategies were: hydropriming for 48 h, osmohardening with KCl or CaCl2 for

Muhammad Farooq; Shahzad M. A. Barsa; Abdul Wahid

2006-01-01

383

Economic Analysis of Planting Forests on Rice Lands in Texas: Sequestering Carbon and Avoiding Methane Production  

Microsoft Academic Search

Global climate change is predicted due to increases in greenhouse gasses (i.e. CO2, CH4, CFCs, N2O, O3) in the atmosphere caused by human activities. The atmospheric concentration of methane (CH4), which absorbs and retains heat 21 times more effectively than CO2, has increased. Anaerobic bacterial activity in rice paddies constitutes one of major emission sources of CH4. The rice fields

G. D. Kronrad; C. Huang

2005-01-01

384

Inheritance of early elongation ability in floating rice revealed by diallel and QTL analyses  

Microsoft Academic Search

In floating rice, stem elongation begins much earlier than in non-floating rice, which is the major survival mechanism for flooding. Inheritance of this early elongation ability was studied using diallel and quantitative trait locus (QTL) analyses. The diallel analysis was undertaken using a set of 6×6 half-diallel crosses involving four floating (‘Goai’, ‘Habiganj Aman VIII’, ‘Badal 106’, and Oryza rufipogon

K. Nemoto; Y. Ukai; D.-Q. Tang; Y. Kasai; M. Morita

2004-01-01

385

Genetic engineering approaches to improve the bioavailability and the level of iron in rice grains  

Microsoft Academic Search

Iron deficiency is the most widespread micronutrient deficiency world-wide. A major cause is the poor absorption of iron from\\u000a cereal and legume-based diets high in phytic acid. We have explored three approaches for increasing the amount of iron absorbed\\u000a from rice-based meals. We first introduced a ferritin gene from Phaseolus vulgaris into rice grains, increasing their iron content up to

P. Lucca; R. Hurrell; I. Potrykus

2001-01-01

386

Highly asymmetric rice genomes  

PubMed Central

Background Individuals in the same species are assumed to share the same genomic set. However, it is not unusual to find an orthologous gene only in small subset of the species, and recent genomic studies suggest that structural rearrangements are very frequent between genomes in the same species. Two recently sequenced rice genomes Oryza sativa L. var. Nipponbare and O. sativa L. var. 93-11 provide an opportunity to systematically investigate the extent of the gene repertoire polymorphism, even though the genomic data of 93-11 derived from whole-short-gun sequencing is not yet as complete as that of Nipponbare. Results We compared gene contents and the genomic locations between two rice genomes. Our conservative estimates suggest that at least 10% of the genes in the genomes were either under presence/absence polymorphism (5.2%) or asymmetrically located between genomes (4.7%). The proportion of these "asymmetric genes" varied largely among gene groups, in which disease resistance (R) genes and the RLK kinase gene group had 11.6 and 7.8 times higher proportion of asymmetric genes than housekeeping genes (Myb and MADS). The significant difference in the proportion of asymmetric genes among gene groups suggests that natural selection is responsible for maintaining genomic asymmetry. On the other hand, the nucleotide diversity in 17 R genes under presence/absence polymorphism was generally low (average nucleotide diversity = 0.0051). Conclusion The genomic symmetry was disrupted by 10% of asymmetric genes, which could cause genetic variation through more unequal crossing over, because these genes had no allelic counterparts to pair and then they were free to pair with homologues at non-allelic loci, during meiosis in heterozygotes. It might be a consequence of diversifying selection that increased the structural divergence among genomes, and of purifying selection that decreased nucleotide divergence in each R gene locus.

Ding, Jing; Araki, Hitoshi; Wang, Qiang; Zhang, Pengfei; Yang, Sihai; Chen, Jian-Qun; Tian, Dacheng

2007-01-01

387

7 CFR 319.55a - Administrative instructions relating to entry of rice straw and rice hulls into Guam.  

Code of Federal Regulations, 2013 CFR

...to entry of rice straw and rice hulls into Guam. 319.55a Section 319.55a Agriculture...to entry of rice straw and rice hulls into Guam. Rice straw and rice hulls may be imported into Guam without further permit, other...

2013-01-01

388

Use of a conceptual model of societal drivers of ecological change in South Florida: Implications of an ecosystem management scenario  

Microsoft Academic Search

Human-dominated ecosystems such as in South Florida's Everglades region are greatly affected by societal actions and choices, and efforts to restore degraded ecosystems must take into account the societal drivers of ecosystem change. A conceptual model of societal-ecological interactions within the region illustrates connections between major societal drivers, such as water management and land use, and ecological stressors, such as

Christine C. Harwell; Christopher W. Deren; George H. Snyder; William D. Solecki; James Wilson; Mark A. Harwell

1999-01-01

389

A collection of glycosyltransferases from rice (Oryza sativa) exposed to atrazine.  

PubMed

The rice (Oryza sativa) GTs belong to a super family possibly with hundreds of members. However, which GTs are involved in plant response to toxic chemicals is unknown. Here, we demonstrated 59 novel GT genes screened from our recent genome-wide sequencing datasets of rice crops exposed to atrazine (a herbicide persistent in ecosystems). Analysis of GT genes showed that most of the GTs contain functional domains typically found in proteins transferring glycosyl moieties to their target compounds. A phylogenetic analysis revealed that many GT genes from different families have diverse cis-elements necessary for response to biotic and environmental stresses. Experimental validation for the GTs was undertaken through a microarray, and 36 GT genes were significantly detected with an expression pattern similar to that from deep-sequencing datasets. Furthermore, 12 GT genes were randomly selected and confirmed by quantitative real-time RT-PCR. Finally, the special activity of total GTs was determined in rice roots and shoots, with an increased activity under the atrazine exposure. This response was closely associated with atrazine absorption in the rice tissues. These results indicate that exposure to atrazine can trigger specific GT genes and enzyme activities in rice. PMID:24042130

Lu, Yi Chen; Yang, Sheng Ning; Zhang, Jing Jing; Zhang, Jia Jun; Tan, Li Rong; Yang, Hong

2013-09-13

390

Integrating Climate and Ecosystems Science to Inform Marine Ecosystem Management  

NASA Astrophysics Data System (ADS)

Climate change has consistently been identified as a top threat to sensitive marine ecosystems such as coral reefs. However, such assessments are made largely by reference to coarse-scale global climate models and limited empirical research from single disciplines. This paper describes a NOAA-wide effort to bring together climatologists, ecologists, oceanographers, and ecosystem managers to identify critical climate-ecosystem connections, and to develop a suite of integrated information products that will improve an ecosystem manager's ability to identify potential climate impacts and variability at scales relevant to the ecosystems they manage. This Integrated Marine Protected Area Climate Tools (IMPACT) project references historical climatologies against ecological impacts to provide more relevant, quantified information to ecosystem stewards seeking to understand and plan for future environmental stresses.

Shein, K. A.; Marzin, C.; Hendee, J.; Pirhalla, D.; Causey, B.; Brandon, T. B.

2011-12-01

391

A Historical Analysis of the Relationship Between Rice Production and PDSI Values in Sri Lanka  

NASA Astrophysics Data System (ADS)

As world population grows, there are ever increasing demands being placed on the food production systems throughout the world. Climate change is complicating these stressors even further through more frequent severe weather events. In the developing world, where there are fewer resources to mitigate the effects of climate change, the combination of these two factors can have drastic consequences. In Sri Lanka, farmers in major rice production areas of the country are already struggling to produce enough rice, a staple food of the local diet, and a severe wet or dry spell could be ruinous. Faced with a changing climate and a growing demand for rice, it is important to be able to anticipate how climatic changes will affect rice production. By examining how extreme wet and dry spells have historically affected rice production, decision makers may be better able to predict and prepare for potential food shortages. We conducted an analysis of historic temperature, precipitation, and rice production statistics in order to determine the effects of extreme wet and dry spells on rice production. We also created a timeline of major developments in Sri Lankan agriculture in order to compare effects on rice production due to changes in agricultural practices with meteorological changes. Historical temperature and precipitation data were used to calculate the Palmer Drought Severity Index (PDSI) for a number of stations distributed throughout the Mahaweli river basin. The basin, the largest in the country, contains three different climatic regions - dry, intermediate, and wet - that all receive different amounts of annual precipitation. The PDSI values were used to quantify drought and wetness during the Yala (April-September) and Maha (October-March) growing seasons. Analysis of historical PDSI values, agricultural advances, and rice production statistics shows great promise for anticipating and mitigating future food shortages.

Jacobi, J. H.; Hornberger, G. M.

2011-12-01

392

Land Floras: The Major Late Phanerozoic Atmospheric Carbon Dioxide\\/Oxygen Control  

Microsoft Academic Search

Since at least the late Mesozoic, the abundance of terrestrial vegetation has been the major factor in atmospheric carbon dioxide\\/oxygen fluctuations. Of modern ecosystem types occupying more than 1 percent of the earth's surface, productivity\\/area ratios of terrestrial ecosystems (excepting tundra and alpine meadow, desert scrub, and rock, ice, and sand) exceed those of marine ecosystems and probably have done

Dewey M. McLean

1978-01-01

393

Adaptation to flooding during emergence and seedling growth in rice and weeds, and implications for crop establishment  

PubMed Central

Background and aims Direct seeding of rice is being adopted in rainfed and irrigated lowland ecosystems because it reduces labour costs in addition to other benefits. However, early flooding due to uneven fields or rainfall slows down seed germination and hinders crop establishment. Conversely, early flooding helps suppress weeds and reduces the costs of manual weeding and/or dependence on herbicides; however, numerous weed species are adapted to lowlands and present challenges for the use of flooding to control weeds. Advancing knowledge on the mechanisms of tolerance of flooding during germination and early growth in rice and weeds could facilitate the development of improved rice varieties and effective weed management practices for direct-seeded rice. Principal results Rice genotypes with a greater ability to germinate and establish in flooded soils were identified, providing opportunities to develop varieties suitable for direct seeding in flooded soils. Tolerance of flooding in these genotypes was mostly attributed to traits associated with better ability to mobilize stored carbohydrates and anaerobic metabolism. Limited studies were undertaken in weeds associated with lowland rice systems. Remaining studies compared rice and weeds and related weed species such as Echinochloa crus-galli and E. colona or compared ecotypes of the same species of Cyperus rotundus adapted to either aerobic or flooded soils. Conclusions Tolerant weeds and rice genotypes mostly developed similar adaptive traits that allow them to establish in flooded fields, including the ability to germinate and elongate faster under hypoxia, mobilize stored starch reserves and generate energy through fermentation pathways. Remarkably, some weeds developed additional traits such as larger storage tubers that enlarge further in deeper flooded soils (C. rotundus). Unravelling the mechanisms involved in adaptation to flooding will help design management options that will allow tolerant rice genotypes to adequately establish in flooded soils while simultaneously suppressing weeds.

Ismail, Abdelbagi M.; Johnson, David E.; Ella, Evangelina S.; Vergara, Georgina V.; Baltazar, Aurora M.

2012-01-01

394

Processing conditions, rice properties, health and environment.  

PubMed

Rice is the staple food for nearly two-thirds of the world's population. Food components and environmental load of rice depends on the rice form that is resulted by different processing conditions. Brown rice (BR), germinated brown rice (GBR) and partially-milled rice (PMR) contains more health beneficial food components compared to the well milled rice (WMR). Although the arsenic concentration in cooked rice depends on the cooking methods, parboiled rice (PBR) seems to be relatively prone to arsenic contamination compared to that of untreated rice, if contaminated water is used for parboiling and cooking. A change in consumption patterns from PBR to untreated rice (non-parboiled), and WMR to PMR or BR may conserve about 43-54 million tons of rice and reduce the risk from arsenic contamination in the arsenic prone area. This study also reveals that a change in rice consumption patterns not only supply more food components but also reduces environmental loads. A switch in production and consumption patterns would improve food security where food grains are scarce, and provide more health beneficial food components, may prevent some diseases and ease the burden on the Earth. However, motivation and awareness of the environment and health, and even a nominal incentive may require for a method switching which may help in building a sustainable society. PMID:21776212

Roy, Poritosh; Orikasa, Takahiro; Okadome, Hiroshi; Nakamura, Nobutaka; Shiina, Takeo

2011-06-03

395

Processing Conditions, Rice Properties, Health and Environment  

PubMed Central

Rice is the staple food for nearly two-thirds of the world’s population. Food components and environmental load of rice depends on the rice form that is resulted by different processing conditions. Brown rice (BR), germinated brown rice (GBR) and partially-milled rice (PMR) contains more health beneficial food components compared to the well milled rice (WMR). Although the arsenic concentration in cooked rice depends on the cooking methods, parboiled rice (PBR) seems to be relatively prone to arsenic contamination compared to that of untreated rice, if contaminated water is used for parboiling and cooking. A change in consumption patterns from PBR to untreated rice (non-parboiled), and WMR to PMR or BR may conserve about 43–54 million tons of rice and reduce the risk from arsenic contamination in the arsenic prone area. This study also reveals that a change in rice consumption patterns not only supply more food components but also reduces environmental loads. A switch in production and consumption patterns would improve food security where food grains are scarce, and provide more health beneficial food components, may prevent some diseases and ease the burden on the Earth. However, motivation and awareness of the environment and health, and even a nominal incentive may require for a method switching which may help in building a sustainable society.

Roy, Poritosh; Orikasa, Takahiro; Okadome, Hiroshi; Nakamura, Nobutaka; Shiina, Takeo

2011-01-01

396

Red Yeast Rice Prepared from Thai Glutinous Rice and the Antioxidant Activities  

Microsoft Academic Search

Red yeast rice which is a product of solid fermentation was prepared from several kinds of Thai glutinous rice (Oryza sativa L.) cv. Korkor 6 (RD6), Kam (Kam) and Sanpatong1 (SPT1). Monascus purpureus CMU001 isolated from available Chinese red yeast rice was used as the fermentation starter. The analysis for the presence of antioxidant activity in red yeast rice was

Em-on Chairote; Griangsak Chairote; Saisamorn Lumyong

397

Factors influencing ALS-resistant gene transfer from CL (tm) rice to red rice.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Red rice (Oryza sativa L.) is hard to control due to its genetic similarity to cultivated rice. Herbicide-resistant Clearfield ™ (CL) rice now offers an excellent option for red rice control. However, sustainability of CL technology at the producers’ level will be dictated by various factors. Promi...

398

Antioxidant activity and nutritional quality of traditional red-grained rice varieties containing proanthocyanidins.  

PubMed

Proanthocyanidin-containing rice varieties have been rarely reported. Antioxidant capacity, major antioxidant components, and nutritional parameters of eight traditional red-grained rice varieties containing proanthocyanidins grown in Sri Lanka were investigated. The tested traditional red varieties, on the average, had over sevenfold higher both total antioxidant capacity and phenolic content than three light brown-grained new-improved rice varieties. Major antioxidant phenolic compounds identified in this study included proanthocyanidins, phenolic acids and ?-oryzanols (ferulic acid derivatives). Proanthocyanidins were detected only in the traditional red varieties, but not found in new-improved ones. Most traditional red varieties also contained significantly higher levels of protein with well balanced amino acids and higher contents of fat, fibre and vitamin E (tocopherols and tocotrienols) than the new-improved ones. Great variations in antioxidant capacity, major phenolics, and nutritional parameters were observed among different rice varieties. These Sri Lankan traditional red-grained rice varieties containing proanthocyanidins may be used as important genetic sources for rice breeding. PMID:23411226

Gunaratne, Anil; Wu, Kao; Li, Dongqin; Bentota, Amitha; Corke, Harold; Cai, Yi-Zhong

2012-12-08

399

Water consumption of agriculture and natural ecosystems at the Amu Darya in Lebap Province, Turkmenistan  

NASA Astrophysics Data System (ADS)

The Amu Darya is the main water source for whole Turkmenistan, but also for the regions Khorezm and Karakalpakistan in Uzbekistan. Due to the arid climate in the Amu Darya river basin, agriculture depends on irrigation with river water being the major source of water. Also the natural ecosystems depend on river water. Until end of the 1970s, the Amu Darya flew into the Aral Sea and, together with the Syr Darya, sustained its water level. From the 1960s until today the area under irrigation has been strongly enlarged. During Soviet Union times, mainly cotton was planted on the newly reclaimed land. After independence, new land was reclaimed, in order to grow wheat. In the course of this land reclamation, the downstream section of the Amu Darya, i.e. in Karakalpakistan faces severe water shortage. Today, the Amu Darya only occasionally reaches the previous shore line of the Aral Sea. Against this background, it is necessary that water consumption along the Amu Darya is limited and water is used efficiently, in order to ensure water supply for downstream water users. The province Lebap in Turkmenistan is located at the middle reaches of the Amu Darya. Thus, it is an example of an administrative unit, which consumes water from the Amu Darya and which should release a sufficient amount of water downstream. Furthermore, Lebap harbours one of the last near-natural riparian forests of Central Asia, i.e. the Amu Darya State Reserve, which also is a water consumer. Therefore, we estimate the water consumption of agriculture (cotton, wheat, rice, and house gardens) and the natural ecosystems within Lebap Province. Water consumption refers to the actual evapo-transpiration. We use Landsat ETM and TM satellite images, in order to produce maps of the actual evapo-transpiration. Afterwards, a land cover map is laid over the ETa maps, in order to retrieve the ETa of the different crops and natural ecosystems. These results are compared with the water norms and quotas given for Lebap Province.

Thevs, Niels; Ovezmuradov, Kurban

2013-04-01

400

Resistance to green leafhopper ( Nephotettix virescens) and brown planthopper ( Nilaparvata lugens) in transgenic rice expressing snowdrop lectin ( Galanthus nivalis agglutinin; GNA)  

Microsoft Academic Search

Transgenic rice plants expressing snowdrop lectin (Galanthus nivalis agglutinin; GNA) were screened for resistance to green leafhopper (Nephotettix virescens; GLH), a major homopteran pest of rice. Survival was reduced by 29% and 53% (P<0.05) respectively, on plants where GNA expression was tissue-specific (phloem and epidermal layer) or constitutive. Similar levels of resistance in GNA-expressing transgenic rice were previously reported for

Xavier Foissac; Nguyen Thi Loc; Paul Christou; Angharad M. R. Gatehouse; John A. Gatehouse

2000-01-01

401

FDA: Low Levels of Arsenic in Rice  

MedlinePLUS

... enable JavaScript. FDA: Low Levels of Arsenic in Rice Agency still studying effects of long-term consumption ... HealthDay News) -- The levels of arsenic found in rice aren't high enough to be a short- ...

402

Production of Crayfish in Rice Fields.  

National Technical Information Service (NTIS)

A study was conducted to determine how rice (Oryza sativa) and crayfish (Procambarus clarkii) affect each other in the field and to determine optimal stocking rates of crayfish. High rice production correlated with large numbers of adult crayfish present ...

Y. H. Chien J. W. Avault

1980-01-01

403

Blue-Green Algae and Rice.  

National Technical Information Service (NTIS)

Rising costs of the chemical fertilizers used to provide the combined nitrogen needed for rice production have prompted rice researchers to turn their attention to biological nitrogen sources such as blue-green (BGA). Although BGA produced nitrogen when i...

P. A. Roger S. A. Kulasooriya

1980-01-01

404

The Tragedy of Ecosystem Services  

Microsoft Academic Search

Brief Abstract. Current economic,incentives encourage the development,of private lands for marketable commodities,at the expense of ecosystem services. Reinforcing this market failure, property law assigns no legal rights to ecosystem services. Abstract.Derived from funds of natural capital, ecosystem services contribute greatly to human welfare yet are rarely traded in markets. Supporting, regulating, and some cultural and provisioningecosystem services are decliningdue to

Christopher L. Lant; J. B. Ruhl; Steven E. Kraft

2008-01-01

405

Ecosystem engineering, experiment, and evolution  

Microsoft Academic Search

This paper argues that philosophers should pay more attention to the idea of ecosystem engineering and to the scientific literature\\u000a surrounding it. Ecosystem engineering is a broad but clearly delimited concept that is less subject to many of the “it encompasses too much” criticisms that philosophers\\u000a have directed at niche construction. The limitations placed on the idea of ecosystem engineering

Trevor Pearce

406

Illustrations of Interconnectedness in Ecosystems  

NSDL National Science Digital Library

This module introduces the idea of interconnectedness among ecosystem components and describes a number of scenarios that illustrate the concept. Interconnectedness is a fundamental ecological concept, a common theme in natural resource/environmental science programs and a foundational component of ecosystem-based management of natural resources. Two introductory activities require students to diagram ecosystem interconnections. Brief descriptions of 13 additional scenarios are provided, along with references to and descriptions of supporting video, print and web-based resources.

Cudmore, Wynn

2010-08-20

407

Genetic dissection of the biotic stress response using a genome-scale gene network for rice  

PubMed Central

Rice is a staple food for one-half the world's population and a model for other monocotyledonous species. Thus, efficient approaches for identifying key genes controlling simple or complex traits in rice have important biological, agricultural, and economic consequences. Here, we report on the construction of RiceNet, an experimentally tested genome-scale gene network for a monocotyledonous species. Many different datasets, derived from five different organisms including plants, animals, yeast, and humans, were evaluated, and 24 of the most useful were integrated into a statistical framework that allowed for the prediction of functional linkages between pairs of genes. Genes could be linked to traits by using guilt-by-association, predicting gene attributes on the basis of network neighbors. We applied RiceNet to an important agronomic trait, the biotic stress response. Using network guilt-by-association followed by focused protein–protein interaction assays, we identified and validated, in planta, two positive regulators, LOC_Os01g70580 (now Regulator of XA21; ROX1) and LOC_Os02g21510 (ROX2), and one negative regulator, LOC_Os06g12530 (ROX3). These proteins control resistance mediated by rice XA21, a pattern recognition receptor. We also showed that RiceNet can accurately predict gene function in another major monocotyledonous crop species, maize. RiceNet thus enables the identification of genes regulating important crop traits, facilitating engineering of pathways critical to crop productivity.

Lee, Insuk; Seo, Young-Su; Coltrane, Dusica; Hwang, Sohyun; Oh, Taeyun; Marcotte, Edward M.; Ronald, Pamela C.

2011-01-01

408

BGI-RIS: an integrated information resource and comparative analysis workbench for rice genomics.  

PubMed

Rice is a major food staple for the world's population and serves as a model species in cereal genome research. The Beijing Genomics Institute (BGI) has long been devoting itself to sequencing, information analysis and biological research of the rice and other crop genomes. In order to facilitate the application of the rice genomic information and to provide a foundation for functional and evolutionary studies of other important cereal crops, we implemented our Rice Information System (BGI-RIS), the most up-to-date integrated information resource as well as a workbench for comparative genomic analysis. In addition to comprehensive data from Oryza sativa L. ssp. indica sequenced by BGI, BGI-RIS also hosts carefully curated genome information from Oryza sativa L. ssp. japonica and EST sequences available from other cereal crops. In this resource, sequence contigs of indica (93-11) have been further assembled into Mbp-sized scaffolds and anchored onto the rice chromosomes referenced to physical/genetic markers, cDNAs and BAC-end sequences. We have annotated the rice genomes for gene content, repetitive elements, gene duplications (tandem and segmental) and single nucleotide polymorphisms between rice subspecies. Designed as a basic platform, BGI-RIS presents the sequenced genomes and related information in systematic and graphical ways for the convenience of in-depth comparative studies (http://rise.genomics.org.cn/). PMID:14681438

Zhao, Wenming; Wang, Jing; He, Ximiao; Huang, Xiaobing; Jiao, Yongzhi; Dai, Mingtao; Wei, Shulin; Fu, Jian; Chen, Ye; Ren, Xiaoyu; Zhang, Yong; Ni, Peixiang; Zhang, Jianguo; Li, Songgang; Wang, Jian; Wong, Gane Ka-Shu; Zhao, Hongyu; Yu, Jun; Yang, Huanming; Wang, Jun

2004-01-01

409

Global value of GM rice: a review of expected agronomic and consumer benefits.  

PubMed

Unlike the other major crops, no genetically modified (GM) varieties of rice have been commercialized at a large scale. Within the next 2-3 years new transgenic rice varieties could be ready for regulatory approval and subsequent commercialization, though. Given the importance of rice as staple crop for many of the world's poorest people, this will have implications for the alleviation of poverty, hunger and malnutrition. Thus, policy-makers need to be aware of the potential benefits of GM rice. We provide an overview of the literature and discuss the evidence on expected agronomic and consumer benefits of genetically engineered rice. We find that while GM rice with improved agronomic traits could deliver benefits similar to already commercialized biotechnology crops, expected benefits of consumer traits could be higher by an order of magnitude. By aggregating the expected annual benefits, we estimate the global value of GM rice to be US$64 billion per year. This is only an indicative value, as more GM varieties will become available in future. Nevertheless, such a figure can help guide policy-makers when deciding on the approval or funding of biotechnology crops and it may also raise awareness among consumers about what is at stake for their societies. PMID:23628812

Demont, Matty; Stein, Alexander J

2013-04-26

410

Quality of head and chalky rice and deterioration of eating quality by chalky rice  

Microsoft Academic Search

Chalk, an opaque area in the rice grain, is an important quality characteristic in rice and occurs most commonly when grains\\u000a are exposed to high temperatures during development. Chalky rice decreases the value of rice because of its undesirable appearance\\u000a and eating quality for consumers. We investigated the chemical composition, morphological structure, cooking, texture properties\\u000a of cooked rice, and pasting

Areum Chun; Jin Song; Kee-Jong Kim; Ho-Jin Lee

2009-01-01

411

Concentration of chlorine in rice plant components  

Microsoft Academic Search

Rice plants were grown in an experimental field and separated at harvest into different components, including polished rice,\\u000a rice bran, hull, straw and root. The distribution of chlorine in these components was determined by instrumental neutron activation\\u000a analysis. The concentration of chlorine in the roots was the highest (4800 mg·kg?1 dry wt.) and that in the polished rice was the

H. Tsukada; A. Takeda

2008-01-01

412

Dynamic fragility of oceanic coral reef ecosystems  

PubMed Central

As one of the most diverse and productive ecosystems known, and one of the first ecosystems to exhibit major climate-warming impacts (coral bleaching), coral reefs have drawn much scientific attention to what may prove to be their Achilles heel, the thermal sensitivity of reef-building corals. Here we show that climate change-driven loss of live coral, and ultimately structural complexity, in the Seychelles results in local extinctions, substantial reductions in species richness, reduced taxonomic distinctness, and a loss of species within key functional groups of reef fish. The importance of deteriorating physical structure to these patterns demonstrates the longer-term impacts of bleaching on reefs and raises questions over the potential for recovery. We suggest that isolated reef systems may be more susceptible to climate change, despite escaping many of the stressors impacting continental reefs.

Graham, Nicholas A. J.; Wilson, Shaun K.; Jennings, Simon; Polunin, Nicholas V. C.; Bijoux, Jude P.; Robinson, Jan

2006-01-01

413

Organic carbon hidden in urban ecosystems  

PubMed Central

Urbanization is widely presumed to degrade ecosystem services, but empirical evidence is now challenging these assumptions. We report the first city-wide organic carbon (OC) budget for vegetation and soils, including under impervious surfaces. Urban soil OC storage was significantly greater than in regional agricultural land at equivalent soil depths, however there was no significant difference in storage between soils sampled beneath urban greenspaces and impervious surfaces, at equivalent depths. For a typical U.K. city, total OC storage was 17.6?kg m?2 across the entire urban area (assuming 0?kg m?2 under 15% of land covered by buildings). The majority of OC (82%) was held in soils, with 13% found under impervious surfaces, and 18% stored in vegetation. We reveal that assumptions underpinning current national estimates of ecosystem OC stocks, as required by Kyoto Protocol signatories, are not robust and are likely to have seriously underestimated the contributions of urban areas.

Edmondson, Jill L.; Davies, Zoe G.; McHugh, Nicola; Gaston, Kevin J.; Leake, Jonathan R.

2012-01-01

414

Natural hazards and genetic diversity in rice  

Microsoft Academic Search

Rice crop diversity hasdecreased dramatically in the recent past.Understanding the causes that underlie theevident genetic erosion is critical for thefood security of subsistence rice farmers andbiodiversity. Our study shows that farmers inthe northeastern Philippines had a markedreduction in rice diversity from 1996 to 1998.The ultimate causes were a drought resultingfrom the El Niño phenomenon in 1997 andflooding due to two

Stephen R. Morin; Marlon Calibo; Marilyn Garcia-Belen; Jean-Louis Pham; Florencia Palis

2002-01-01

415

Is Growth in Bangladesh's Rice Production Sustainable?  

Microsoft Academic Search

The current level of per capita production of rice in Bangladesh can be sustained only through increased yields of modern rice varieties.The recent growth of foodgrain (primarily rice) production in Bangladesh has outpaced population growth largely because of the spread of green revolution technology. The transition from being labeled a \\

John Baffes; Madhur Gautam

1996-01-01

416

Rice phytochemical identification and genetic diversity  

Technology Transfer Automated Retrieval System (TEKTRAN)

Whole-grain rice, especially the dark color bran rice, contains high phenolic content and antioxidant capacity, which have potential in disease prevention. However, little information is available regarding the differences in phytochemical profiles of rice of different bran color. Studies indicated ...

417

CO-PRODUCTS FROM RICE PROCESSING  

Technology Transfer Automated Retrieval System (TEKTRAN)

The first unit operation in milling of rice removes the hull to produce brown rice. The hull is the least nutritious part of rice containing about 20% silica. Until now, limited commercial uses of hulls include steam generation, filtration media, and poultry bedding material. New uses being deve...

418

WARM: A SCIENTIFIC GROUP ON RICE MODELLING  

Microsoft Academic Search

This paper is an open letter aiming at inviting all researchers and technicians working on rice and\\/or on modelling aspects that can be related to rice to participate to a scientific exchange group. The WARM (Water Accounting Rice Model) model is currently the result of an unofficial cooperation among researchers working at the Joint Research Centre of the European Commission

Roberto Confalonieri; Marco Acutis; Marcello Donatelli; Gianni Bellocchi; Luigi Mariani; Mirco Boschetti; Daniela Stroppiana; Stefano Bocchi; Francesco Vidotto; Dario Sacco; Carlo Grignani

2005-01-01

419

CAN INDONESIA TRUST THE WORLD RICE MARKET?  

Microsoft Academic Search

Geography suggests that Indonesia will continue as a net rice importer for the foreseeable future, because it is an island nation without dominant river deltas providing abundant water and flat land suitable for rice growing. Yet policy makers remain reluctant to use the world rice market to achieve domestic food security goals for at least two reasons. First, there is

David Dawe

2008-01-01

420

Global climate changes and rice food security  

Microsoft Academic Search

Reducing hunger and poverty are the key United Nations Millenium Development Goals. This was the main reason for the UN declaration of the International Year of Rice 2004. In 2002, rice was the source of more than 500 calories per person per day for over 3 billion people (FAOSTAT). Furthermore, rice cultivation is the principal activity and source of income

N. V. Nguyen

421

INSIGHTS INTO THE PARENTAGE OF RICE/RED RICE CROSSES USING SSR ANALYSIS OF U.S. RICE CULTIVARS AND RED RICE POPULATIONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Since the introduction of herbicide (imidazolinone)-resistant rice cultivars into the southern U.S. in 2002, the land area planted to these cultivars has increased steadily, primarily due to the dramatic improvement in control of red rice. At the same time, however, the rice industry has become inc...

422

THE HYDROLOGIC SYSTEM: GEOMORPHIC AND HYDROGEOLOGIC CONTROLS ON SURFACE AND SUBSURFACE FLOW REGIMES IN RIPARIAN MEADOW ECOSYSTEMS IN THE CENTRAL GREAT BASIN  

EPA Science Inventory

Riparian corridors in upland watersheds in the Great Basin of central Nevada contain the majority of the region's biodiversity. Water, in both surface and subsurface flow regimes, is an important resource sustaining these sensitive ecosystems and other similar riparian ecosystem...

423

POLLUTION AND ECOSYSTEM HEALTH - ASSESSING ECOLOGICAL CONDITION OF COASTAL ECOSYSTEMS  

EPA Science Inventory

Summers, Kevin. 2004. Pollution and Ecosystem Health - Assessing Ecological Condition of Coastal Ecosystems. Presented at the White Water to Blue Water (WW2BW) Miami Conference, 21-26 March 2004, Miami, FL. 1 p. (ERL,GB R973). Throughout the coastal regions and Large Mari...

424

ECOSYSTEM SERVICES: Benefits Supplied to Human Societies by Natural Ecosystems  

Microsoft Academic Search

SUMMARY Human societies derive many essential goods from natural ecosystems, including seafood, game animals, fodder, fuelwood, timber, and pharmaceutical products. These goods represent important and familiar parts of the economy. What has been less appreciated until recently is that natural ecosystems also perform fundamental life-support services without which human civilizations would cease to thrive. These include the purification of air

Gretchen C. Daily; Susan Alexander; Paul R. Ehrlich; Larry Goulder; Jane Lubchenco; Pamela A. Matson; Harold A. Mooney; Sandra Postel; Stephen H. Schneider; David Tilman; George M. Woodwell

1997-01-01

425

Ecosystem Services Research Program: LTG 4: Ecosystem specific studies: wetlands  

EPA Science Inventory

Includes review of ecosystem services derived from marine coastal, Great Lakes coastal, and isolated wetlands. Of particular interest is the development of guidelines to implement the 2008 EPA and ACE rules which require, for the first time, that specific ecosystem services be c...

426

Identification and quantification of anthocyanin pigments in colored rice.  

PubMed

Anthocyanin pigments from varieties of black, red and wild rice were identified and quantified to evaluate their potential as nutritional function, natural colorants or functional food ingredients. Anthocyanin extraction was conducted with acidified methanol with 0.1M HCl (85:15, v/v) and identification of anthocyanin, aglycone and sugar moieties was conducted by comparison with purified standards by HPLC, Ultraviolet-Visible absorption spectrophotometer and paper chromatography. Black and wild rice showed three different types of pigments by HPLC whereas red rice variety did not show any anthocyanins. Out of three pigments detected, one (peak 2) was characterized as cyanidin-3-glucoside (C3G) by comparison of spectroscopic and chromatographic properties with an authentic standard, and another (peak 3) was tentatively identified as cyanidin-fructoside on the basis of spectroscopic properties with lambda(max) of aglycone in 1% HCl methanol at 537 nm, electrospray ionization mass spectra with major ions at 449 and 287 m/z and chromatographic properties. But another pigment (peak 1) has not been characterized. The most abundant anthocyanin in black and wild rice was C3G. PMID:20126365

Kim, Min-Kyoung; Kim, Han-Ah; Koh, Kwangoh; Kim, Hee-Seon; Lee, Young Sang; Kim, Yong Ho

2008-03-31

427

Detection and diagnosis of rice-infecting viruses  

PubMed Central

Rice-infecting viruses have caused serious damage to rice production in Asian, American, and African countries, where about 30 rice viruses and diseases have been reported. To control these diseases, developing accurate, quick methods to detect and diagnose the viruses in the host plants and any insect vectors of the viruses is very important. Based on an antigen–antibody reaction, serological methods such as latex agglutination reaction and enzyme-linked immunosorbent assay have advanced to detect viral particles or major proteins derived from viruses. They aid in forecasting disease and surveying disease spread and are widely used for virus detection at plant protection stations and research laboratories. From the early 2000s, based on sequence information for the target virus, several other methods such as reverse transcription-polymerase chain reaction (RT-PCR) and reverse transcription-loop-mediated isothermal amplification have been developed that are sensitive, rapid, and able to differentiate closely related viruses. Recent techniques such as real-time RT-PCR can be used to quantify the pathogen in target samples and monitor population dynamics of a virus, and metagenomic analyses using next-generation sequencing and microarrays show potential for use in the diagnosis of rice diseases.

Uehara-Ichiki, Tamaki; Shiba, Takuya; Matsukura, Keiichiro; Ueno, Takanori; Hirae, Masahiro; Sasaya, Takahide

2013-01-01

428

Effect of rice cultivars on root-associated methanotrophic communities  

NASA Astrophysics Data System (ADS)

Rice agriculture represents a major source of the greenhouse gas methane. However, a large amount of methane is oxidized by methanotrophic bacteria before being released to the atmosphere. Methanotrophs are characterized by their unique ability to use methane as sole source for carbon and energy. They are located at oxic-anoxic interfaces where methane and oxygen are present, such as the rhizosphere. Although they have been studied extensively in the past, only little is known about natural or anthropogenic factors influencing their large diversity. In this study, we investigated the effect of 20 different rice cultivars on methanotrophic communities associated with the roots of rice plants. The pmoA gene encoding a subunit of the particulate methane monooxygenase (catalyzing the first step of methane oxidation) was used as a functional and phylogenetic marker and analyzed using two different fingerprinting methods. The well established terminal restriction fragment length polymorphism (T-RFLP) analysis was compared to results obtained using a diagnostic pmoA microarray. Both methods indicated that type Ib (Methylococcus/Methylocaldum) and type II (Methylosinus/Methylocystis) were the predominat methanotrophs located on rice roots. Interestingly, analysis of pmoA transcripts suggested Methylobacter/Methylomonas (type Ia) to present the actively methane oxidizing population in this environment.

Lüke, C.; Frenzel, P.

2009-04-01

429

Identification and quantification of anthocyanin pigments in colored rice  

PubMed Central

Anthocyanin pigments from varieties of black, red and wild rice were identified and quantified to evaluate their potential as nutritional function, natural colorants or functional food ingredients. Anthocyanin extraction was conducted with acidified methanol with 0.1M HCl (85:15, v/v) and identification of anthocyanin, aglycone and sugar moieties was conducted by comparison with purified standards by HPLC, Ultraviolet-Visible absorption spectrophotometer and paper chromatography. Black and wild rice showed three different types of pigments by HPLC whereas red rice variety did not show any anthocyanins. Out of three pigments detected, one (peak 2) was characterized as cyanidin-3-glucoside (C3G) by comparison of spectroscopic and chromatographic properties with an authentic standard, and another (peak 3) was tentatively identified as cyanidin-fructoside on the basis of spectroscopic properties with ?max of aglycone in 1% HCl methanol at 537 nm, electrospray ionization mass spectra with major ions at 449 and 287 m/z and chromatographic properties. But another pigment (peak 1) has not been characterized. The most abundant anthocyanin in black and wild rice was C3G.

Kim, Min-Kyoung; Kim, Han-ah; Koh, Kwangoh; Lee, Young Sang; Kim, Yong Ho

2008-01-01

430

Methane production in rice soil is inhibited by cyanobacteria.  

PubMed

The present study was aimed at understanding the role of cyanobacteria and Azolla in methane production and oxidation in laboratory simulation experiments using soil samples from rice fields. All the seven cyanobacterial strains tested effected a significant decrease in the headspace concentration of methane in flooded soil, incubated under light. Synechocystis sp. was the most effective in retarding methane concentration by 10-20 fold over that in controls without cyanobacteria. The decrease in the headspace concentration of methane was negligible in nonsterile soil samples, inoculated with Synechocystis sp. and then incubated under dark. Moist soil cores (0-5 cm depth), collected from rice fields that had been treated with urea in combination with a cyanobacterial mixture, Azolla microphylla, or cyanobacterial mixture plus A. microphylla, effected distinctly more rapid decrease in the headspace concentration of methane added at 200 microl(-1) than did the soil cores from plots treated with urea alone (30, 60, 90 and 120 kg N ha(-1)), irrespective of the rate of chemical nitrogen applied to rice fields. Besides, soil cores from plots treated with urea alone at 60, 90 and 120 kg N ha(-1) oxidised methane more rapidly than did the core samples from plots treated with urea alone at 30kg N ha(-1). Cyanobacteria and A. microphylla, applied to flood water, appear to play a major role in mitigation of methane emission from rice fields-through enhanced methane oxidation. PMID:11911608

Prasanna, Radha; Kumar, Vinod; Kumar, Sushil; Yadav, Ashok Kumar; Tripathi, Upasana; Singh, Atul Kumar; Jain, M C; Gupta, Prabhat; Singh, P K; Sethunathan, N

2002-01-01

431

Genome-wide transcriptional changes and defence-related chemical profiling of rice in response to infestation by the rice striped stem borer Chilo suppressalis.  

PubMed

How rice defends itself against pathogen infection is well documented, but little is known about how it defends itself against herbivore attack. We measured changes in the transcriptome and chemical profile of rice when the plant is infested by the striped stem borer (SSB) Chilo suppressalis. Infestation by SSBs resulted in changes in the expression levels of 4545 rice genes; this number accounts for about 8% of the genome and is made up of 18 functional groups with broad functions. The largest group comprised genes involved in metabolism, followed by cellular transport, transcription and cellular signaling. Infestation by SSBs modulated many genes responsible for the biosynthesis of plant hormones and plant signaling. Jasmonic acid (JA), salicylic acid (SA) and ethylene were the major hormones that shaped the SSB-induced defence responses of rice. Many secondary signal transduction components, such as those involved in Ca²? signaling and G-protein signaling, receptor and non-receptor protein kinases, and transcription factors were involved in the SSB-induced responses of rice. Photosynthesis and ATP synthesis from photophosphorylation were restricted by SSB feeding. In addition, SSB infestation induced the accumulation of defence compounds, including trypsin proteinase inhibitors (TrypPIs) and volatile organic compounds. These results demonstrate that SSB-induced defences required rice to reconfigure a wide variety of its metabolic, physiological and biochemical processes. PMID:21534978

Zhou, Guoxin; Wang, Xia; Yan, Feng; Wang, Xia; Li, Ran; Cheng, Jiaan; Lou, Yonggen

2011-06-09

432

Formation and structure of silicon carbide whiskers from rice hulls  

Microsoft Academic Search

A study of the distribution of Si in rice hulls was carried out to aid in understanding the observed formation of SiC whiskers by the thermal decomposition and reaction of these natural materials. Scanning electron microscopy, Auger electron spectroscopy, and energy-dispersive X-ray analysis confirm the presence of a major amount of Si in the inner and outer epidermal regions of

N. K. Sharma; WENDELL S. WILLIAMS; A. Zangvil

1984-01-01

433

Anti-complement activity of essential oils from red and black rice bran.  

PubMed

The volatile essential oils from red and black rice bran were obtained by hydrodistillation using a clevenger-type apparatus, and the components of that oil were analyzed by capillary gas chromatography-mass spectroscopy (GC-MS). The present study involved characterizing the chemical compositions, their amounts and the anti-complement activities of red and black rice bran. The red rice bran essential oils yield was 0.031%, and GC-MS analysis revealed that its major constituents were (E)-?-ocimene (3.12%), nonanal (11.32%), (2E, 4E)-decadienal (2.54%), myristic acid (41.32%), geranyactone (2.41%) and methyl oleate (2.46%). The black rice bran essential oils yield was 0.053%, and GC-MS analysis revealed that its major constituents were nonanal (8.31%), acrylic acid (3.21%), 2-hydroxy-6-methylbenzaldehyde (2.81%), pelargonic acid (4.21%) and myrisitc acid (28.07%). The essential oils showed inhibitory activity against complement system with 50% inhibitory concentrations (IC(50)) values of 246 ppm (red rice bran) and 193 ppm (black rice bran). Also, myristic acid, nonanal, (E)-?-ocimene and pelargonic acid were tested against complement system. Pelargonic acid was shown to moderate activity (50% inhibitory concentration = 132 ?M). PMID:20673187

Chung, Ill-Min; Yeo, Min-A; Kim, Sun-Jin; Moon, Hyung-In

2010-08-02

434

Using C4 photosynthesis to increase the yield of rice-rationale and feasibility.  

PubMed

90% of the world's rice is grown and consumed in Asia, with each hectare of rice-producing land providing food for 27 people. By 2050, because of population growth and increasing urbanisation, each remaining hectare will have to feed at least 43 people. This means that yields must be increased by at least 50% over the next 40 years to prevent mass malnutrition for the 700 million Asians that currently rely on rice for more than 60% of their daily calorific intake. Since predictive models suggest that yield increases of this magnitude can only be achieved by improving photosynthesis, and because evolution has increased photosynthetic efficiency by 50% in the form of the C4 pathway, one solution is to generate C4 rice. However, this is an ambitious goal that requires proof of concept before any major investment of time and money. Here, we discuss approaches that should allow proof of concept to be tested. PMID:18203653

Hibberd, Julian M; Sheehy, John E; Langdale, Jane A

2008-01-18

435

Emergy-based urban ecosystem health assessment: A case study of Baotou, China  

NASA Astrophysics Data System (ADS)

Ecosystem health has been a hot topic of ecosystem management research for years. Considering the urban area as a complex ecosystem consisted of natural, societal and economic entities, urban ecosystem health assessment is necessary to be conducted for the scientific management and proper ecological restoration. Combining with the ecosystem service function of the urban ecosystem, theoretical framework and methodology of the urban ecosystem health assessment based on emergy are proposed and the temporal variation of the health level of the city are also outlined in this paper. Following the principle of ecosystem health assessment, four major factors, including vigor (V), organizational structure (O), resilience (R) and function maintenance (F), are integrated to construct a novel emergy-based urban ecosystem health index (EUEHI). Based on the EUEHI and comparing with those of five other typical Chinese cities, the case study of Baotou city shows that its urban ecosystem health level is steadily arising despite the year 2001 as a turning point. Due to the emphasis on the resource structure adjustment and utilization efficiency, Baotou has obtained a better organizational structure and service function for the total urban ecosystem.

Liu, G. Y.; Yang, Z. F.; Chen, B.; Zhang, Y.; Zhang, L. X.; Zhao, Y. W.; Jiang, M. M.

2009-03-01

436

Ecotoxicology of tropical marine ecosystems  

Microsoft Academic Search

The negative effects of chemical contaminants on tropical marine ecosystems are of increasing concern as human populations expand adjacent to these communities. Watershed streams and ground water carry a variety of chemicals from agricultural, industrial, and domestic activities, while winds and currents transport pollutants from atmospheric and oceanic sources to these coastal ecosystems. The implications of the limited information available

Esther C. Peters; Nancy J. Gassman; Julie C. Firman; Robert H. Richmond; Elizabeth A. Power

1997-01-01

437

Fronts in Large Marine Ecosystems  

Microsoft Academic Search

Oceanic fronts shape marine ecosystems; therefore front mapping and characterization are among the most important aspects of physical oceanography. Here we report on the first global remote sensing survey of fronts in the Large Marine Ecosystems (LME). This survey is based on a unique frontal data archive assembled at the University of Rhode Island. Thermal fronts were automatically derived with

Igor M. Belkin; Peter C. Cornillon; Kenneth Sherman

2009-01-01

438

Understanding ecosystems using statistical physics  

Microsoft Academic Search

I will show, based on analytic theory and computer simulations, that ecosystems are organized in the vicinity of a new type of phase transition quite akin to Bose-Einstein condensation but occurring in a living system without quantum features. A special case of our model is akin to neutral theory, which postulates that an ecosystem can be characterized by random birth

Igor Volkov

2005-01-01

439

Glacier Lakes Ecosystem Experiments Site.  

National Technical Information Service (NTIS)

The Glacier Lakes Ecosystem Experiment Site (GLEES), a 600 ha research watershed at 3200-3400 m elevation in the Snowy Range of SE Wyoming, has been established to examine the effects of atmospheric deposition on alpine and subalpine ecosystems. This docu...

R. C. Musselman

1994-01-01

440

Biodiversity and aquatic ecosystem functioning  

Microsoft Academic Search

Ecosystem functioning depends on multiple interactions between physical, chemical and biological determinants. Indeed, ecosystem processes (productivity and nutrient recycling) result directly from the diversity of functional traits in the biotic communities, which is in turn determined by the species composition and diversity. This species diversity results from both biotic introductions and environmental pressures. As a result, changes in biodiversity in

J.-F. Humbert; U. Dorigo

441

Climate Change and Arctic Ecosystems  

NSDL National Science Digital Library

In this activity, students learn about how climate change is affecting the Arctic ecosystem and then investigate how this change is impacting polar bear populations. Students analyze maps of Arctic sea ice, temperature graphs, and polar bear population data to answer questions about the impact of climate change on the Arctic ecosystem.

Change, Project A.; University, Purdue

442

Describing Services for Service Ecosystems  

Microsoft Academic Search

Service ecosystems are electronic market places and emerge as a result of the shift toward service economies. The aim of service ecosystems is to trade services over the internet. There are still obstacles that impede this new form of market places. Two of these challenges are addressed in this paper: (1) identication of appropriate service proper- ties to specify service

Gregor Scheithauer; Stefan Augustin; Guido Wirtz

2008-01-01

443

Differentially expressed genes distributed over chromosomes and implicated in certain biological processes for site insertion genetically modified rice Kemingdao.  

PubMed

Release of genetically modified (GM) plants has sparked off intensive debates worldwide partly because of concerns about potential adverse unintended effects of GM plants to the agro system and the safety of foods. In this study, with the aim of revealing the molecular basis for unintended effects of a single site insertion GM Kemingdao (KMD) rice transformed with a synthetic cry1Ab gene, and bridging unintended effects of KMD rice through clues of differentially expressed genes, comparative transcriptome analyses were performed for GM KMD rice and its parent rice of Xiushui11 (XS11). The results showed that 680 differentially expressed transcripts were identified from 30-day old seedlings of GM KMD rice. The absolute majority of these changed expression transcripts dispersed and located over all rice chromosomes, and existed physical distance on chromosome from the insertion site, while only two transcripts were found to be differentially expressed within the 21 genes located within 100 kb up and down-stream of the insertion site. Pathway and biology function analyses further revealed that differentially expressed transcripts of KMD rice were involved in certain biological processes, and mainly implicated in two types of pathways. One type was pathways implicated in plant stress/defense responses, which were considerably in coordination with the reported unintended effects of KMD rice, which were more susceptible to rice diseases compared to its parent rice XS11; the other type was pathways associated with amino acids metabolism. With this clue, new unintended effects for changes in amino acids synthesis of KMD rice leaves were successfully revealed. Such that an actual case was firstly provided for identification of unintended effects in GM plants by comparative transciptome analysis. PMID:22811617

Liu, Zhi; Li, Yunhe; Zhao, Jie; Chen, Xiuping; Jian, Guiliang; Peng, Yufa; Qi, Fangjun

2012-07-12

444

Hydraulic conductivity of rice roots.  

PubMed

A pressure chamber and a root pressure probe technique have been used to measure hydraulic conductivities of rice roots (root Lp(r) per m(2) of root surface area). Young plants of two rice (Oryza sativa L.) varieties (an upland variety, cv. Azucena and a lowland variety, cv. IR64) were grown for 31-40 d in 12 h days with 500 micromol m(-2) s(-1) PAR and day/night temperatures of 27 degrees C and 22 degrees C. Root Lp(r) was measured under conditions of steady-state and transient water flow. Different growth conditions (hydroponic and aeroponic culture) did not cause visible differences in root anatomy in either variety. Values of root Lp(r) obtained from hydraulic (hydrostatic) and osmotic water flow were of the order of 10(-8) m s(-1) MPa(-1) and were similar when using the different techniques. In comparison with other herbaceous species, rice roots tended to have a higher hydraulic resistance of the roots per unit root surface area. The data suggest that the low overall hydraulic conductivity of rice roots is caused by the existence of apoplastic barriers in the outer root parts (exodermis and sclerenchymatous (fibre) tissue) and by a strongly developed endodermis rather than by the existence of aerenchyma. According to the composite transport model of the root, the ability to adapt to higher transpirational demands from the shoot should be limited for rice because there were minimal changes in root Lp(r) depending on whether hydrostatic or osmotic forces were acting. It is concluded that this may be one of the reasons why rice suffers from water shortage in the shoot even in flooded fields. PMID:11520872

Miyamoto, N; Steudle, E; Hirasawa, T; Lafitte, R

2001-09-01

445

Iron Biofortification of Myanmar Rice  

PubMed Central

Iron (Fe) deficiency elevates human mortality rates, especially in developing countries. In Myanmar, the prevalence of Fe-deficient anemia in children and pregnant women are 75 and 71%, respectively. Myanmar people have one of the highest per capita rice consumption rates globally. Consequently, production of Fe-biofortified rice would likely contribute to solving the Fe-deficiency problem in this human population. To produce Fe-biofortified Myanmar rice by transgenic methods, we first analyzed callus induction and regeneration efficiencies in 15 varieties that are presently popular because of their high-yields or high-qualities. Callus formation and regeneration efficiency in each variety was strongly influenced by types of culture media containing a range of 2,4-dichlorophenoxyacetic acid concentrations. The Paw San Yin variety, which has a high-Fe content in polished seeds, performed well in callus induction and regeneration trials. Thus, we transformed this variety using a gene expression cassette that enhanced Fe transport within rice plants through overexpression of the nicotianamine synthase gene HvNAS1, Fe flow to the endosperm through the Fe(II)-nicotianamine transporter gene OsYSL2, and Fe accumulation in endosperm by the Fe storage protein gene SoyferH2. A line with a transgene insertion was successfully obtained. Enhanced expressions of the introduced genes OsYSL2, HvNAS1, and SoyferH2 occurred in immature T2 seeds. The transformants accumulated 3.4-fold higher Fe concentrations, and also 1.3-fold higher zinc concentrations in T2 polished seeds compared to levels in non-transgenic rice. This Fe-biofortified rice has the potential to reduce Fe-deficiency anemia in millions of Myanmar people without changing food habits and without introducing additional costs.

Aung, May Sann; Masuda, Hiroshi; Kobayashi, Takanori; Nakanishi, Hiromi; Yamakawa, Takashi; Nishizawa, Naoko K.

2013-01-01

446

Community and Ecosystems  

NSDL National Science Digital Library

This eight-week investigation of ecology and community asks groups of students to make computer presentations to communicate information they have found from the Internet and other sources. Topics include interrelationships between ecosystems, factors affecting nature's balance, habitats, and possible solutions to environmental problems. Students use the scientific method, data collection and analysis, and problem solving techniques to construct their projects. The site provides rubrics, research links, activities to help students along the way and teacher notes about using this project in the curriculum. This project was designed by K-12 teachers to demonstrate engaged learning and effective use of technology. It is structured in such a way that students are responsible for their own learning, and is collaborative, student-driven, and technology dependent.

Dove, Cheryl

1998-05-01

447

Evaluation of estimated daily intake (EDI) of cadmium and lead for rice (Oryza sativa L.) in calcareous soils.  

PubMed

The excessive amounts of cadmium and lead in food chain can cause health problems for humans and ecosystem. Rice is an important food in human diet. Therefore this study was conducted in order to investigate cadmium and Lead concentrations in seed rice (Oryza saliva) of paddy fields in southwest of Iran. A total of 70 rice seed samples were collected from paddy fields in five regions of Khuzestan province, Southwest Iran, during harvesting time. In the samples cadmium and Lead concentrations were measured. To assess the daily intake of Cadmium and Lead by rice, daily consumption of rice was calculated. The results showed that average concentrations of Cadmium and Lead in rice seeds were 273.6 and 121.8??g/kg, respectively. Less than 72% of rice seed samples had Cadmium concentrations above 200??g/kg (i.e. Guide value for cadmium); and less than 3% had Lead concentrations above 150??g/kg (i.e. Guide value for Lead). The estimated daily intakes of cadmium by the local population was calculated to 0.59??g/day?kg bw, which corresponds to 59% of the tolerable daily intakes (i.e. 1??g/day?kg bw). Eleven out of 70 samples (15.71%) exceed the tolerable daily intakes. The dietary intakes for Lead in the local population ranged from 0.22 to 0.47??g/day?kg bw. Tolerable daily intakes for Lead is 3.6??g/day?kg bw. As a whole, long term consumption of the local rice may bear high risk of heavy metal exposure to the consumer in the study region. PMID:23566692

Chamannejadian, Ali; Sayyad, Gholamabbas; Moezzi, Abdolamir; Jahangiri, Alireza

2013-04-08

448

Characterisation of a novel softened rice product.  

PubMed

We developed a novel softened rice by permeating rice with enzymes that catalyse its decomposition. Herein, we characterised the softened rice (SR) and compared it to normal cooked rice (CR) and rice gruel (RG). SR resembled CR but not RG in appearance. Texture analysis showed that SR was the least firm, adhesive, and cohesive of the three rice preparations. SR contained almost the same amount of nutrition per unit mass as CR and twofold as much as RG. Analysis of digests of energy-equivalent amounts of the three rice preparations indicated that SR digests had the lowest quantity of residue and highest quantity of dissolved carbohydrate, maltose and glucose. The molecular weight (MW) range of SR constituents was 10(3)-10(5), whilst those of CR and RG constituents were mainly 10(5)-10(6). These results suggested that enzymatic decomposition of SR improves ease of eating, nutrition value, and digestibility at once. PMID:24128491

Hayashi, Masahiro; Kato, Kumiko; Umene, Shingo; Masunaga, Hiroaki

2013-08-27

449

Nitrogen Application in Irrigated Rice Grown in Mediterranean Conditions: Effects on Grain Yield, Dry Matter Production, Nitrogen Uptake, and Nitrogen Use Efficiency  

Microsoft Academic Search

Field experiments were conducted in the major rice growing area of Chile to evaluate the effects of nitrogen (N) fertilization and site on grain yield and some yield components, dry matter production, N uptake, and N use efficiency in rice cultivar ‘Diamante’. Two sites (indicated as sites 1 and 2) and six N rates (0, 50, 100, 150, 200, and

Pamela Artacho; Claudia Bonomelli; Francisco Meza

2009-01-01

450

Molecular aspects of rice blast disease resistance: Insights from structural and functional analysis of the Pi-ta and AVR-Pita gene pair  

Technology Transfer Automated Retrieval System (TEKTRAN)

Improved resistance to blast disease can benefit from molecular characterization of major blast R genes. The Pi-ta gene in rice prevents the infections of races of the rice blast fungus Magnaporthe grisea containing the corresponding avirulence AVR-Pita gene. Pi-ta, a single copy gene encodes a pr...

451

New insights into the complex and coordinated transcriptional regulation networks underlying rice seed development through cDNA chip-based analysis  

Microsoft Academic Search

Transcription factors (TFs) are major, crucial factors for developmental control. To elucidate the effects of TFs on rice seed development, we generated a cDNA chip containing 325 rice cDNA clones, which are from flowering stage and encode known or putative TFs belonging to 12 different families, and used this chip for expression profiling at 8 continuous seed developmental stages. The

Ke Duan; Yong-Hai Luo; Da Luo; Zhi-Hong Xu; Hong-Wei Xue

2005-01-01

452

High-resolution mapping of Rsn1, a locus controlling sensitivity of rice to a necrosis-inducing phytotoxin from Rhizoctonia solani AG1-IA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rhizoctonia solani is a necrotrophic fungal pathogen that causes disease on all major crop-plant species. Anastomosis group 1-IA is the causal agent of sheath blight of rice (Oryza sativa), one of the most important rice diseases worldwide. R. solani AG-IA produces a necrosis-inducing phytotoxin a...

453

Assessment of Impact of Insecticides on Anagrus nilaparvatae (Pang et Wang) (Hymenoptera: Mymanidae), an Egg Parasitoid of the Rice Planthopper, Nilaparvata lugens (Hemiptera: Delphacidae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

The parasitoid Anagrus Nilaparvatae (Pang et Wang) (Hymenoptera: Mymanidae) is a major natural enemy of the rice planthopper Nilaparvata lugens (Hemiptera: Delphacidae). It plays an important role in the IPM of the rice planthopper. Contact and oral toxicity and residual effect of fourteen pesticide...

454

A Classroom Exercise for Testing Urban Myth: Does Wedding Rice Cause Birds to Explode or Were Ann Landers, Martha Stewart & Bart Simpson Wrong?  

ERIC Educational Resources Information Center

|In this article, the author first provides the history of the wedding rice myth. He then details an interactive class activity that involved students in his large, non-majors biology classes. These students developed a series of experiments that scientifically determined if rice could be harmful to birds. Finally, he provides suggestions on how…

Krupa, James J.

2005-01-01

455

Role of blue green algae biofertilizer in ameliorating the nitrogen demand and fly-ash stress to the growth and yield of rice ( Oryza sativa L.) plants  

Microsoft Academic Search

Rice is a major food crop throughout the world; however, accumulation of toxic metals and metalloids in grains in contaminated environments is a matter of growing concern. Field experiments were conducted to analyze the growth performance, elemental composition (Fe, Si, Zn, Mn, Cu, Ni, Cd and As) and yield of the rice plants (Oryza sativa L. cv. Saryu-52) grown under

R. D. Tripathi; S. Dwivedi; M. K. Shukla; S. Mishra; S. Srivastava; R. Singh; U. N. Rai; D. K. Gupta

2008-01-01

456

Modeling complex ecosystems with the Biome-BGC ecosystem process model  

NASA Astrophysics Data System (ADS)

The WLEF tall tower near Park Falls, WI, provides a unique look at regional-scale carbon fluxes. As part of a suite of 8 towers in the Chequamegon Ecosystem Atmosphere Study (ChEAS), it is a valuable control on upscaling methods such as ecosystem process models. We use the Biome-BGC ecosystem process model over an area within a 4.5-km radius of the tower to test the model's ability to capture the dynamics of this complex ecosystem (30% wetlands). Results suggest that the standard Biome-BGC model is not adequate for estimating the carbon balance of this landscape. There are two reasons for the limitations of the current model: (1) disturbance (e.g., logging) has affected a portion of the landscape, replacing mature forests with rapidly growing smaller forests and (2) wetlands within the region, which include both sedge-dominated and moss-dominated systems. In addition, the ChEAS suite of flux towers provides a valuable test bed for the models, allowing us to explore their similarities, and more importantly, their differences. Some of the features in these models are slated to become part of the new BGC5, the next major model release, and, as such, we must understand the effects of these models on modeled outputs.

Heinsch, F. A.; Cook, B. D.; Mu, Q.; Bond-Lamberty, B.; Bolstad, P. V.; Davis, K. J.; Running, S. W.

2007-05-01

457

Long term flux ecosystem exchange over a Mediterranean shrubland ecosystem  

NASA Astrophysics Data System (ADS)

Only a few long-term studies on inter-annual variability in energy and mass exchanges of Mediterranean shrubland ecosystems have been recently published. Since maquis ecosystems experience a wide variation in inter-annual rainfall and temperature, inter-annual differences in CO2 fluxes are expected. Mediterranean-type ecosystems normally show two main peaks of growth (in spring and fall) and experience sometimes pronounced summer drought periods. Consequently, Mediterranean-type ecosystem behavior is even more complex and responds more dramatically to perturbations in water conditions. In this paper, six years of energy and mass fluxes measured using eddy covariance (EC) technique over a secondary succession shrubland ecosystem (maquis) located in Sardinia, Italy are reported. The main objectives are to understand dynamics of ecosystem carbon cycling and to identify the driving factors affecting ecosystem exchanges. Eddy flux and meteorological data are presented along with soil respiration information. Footprint analysis, friction velocity method, and other turbulent parameters were calculated to verify the accuracy of the eddy covariance CO2 measurements. The energy partitioning exhibited clear seasonal patterns with increasing Bowen ratio values during the drought season. Peak CO2 uptake occurred during spring and autumn showing an evident decrease in summer. The estimate of NEE showed differences among years depending on drought and temperature conditions. The surface conductance was clearly depressed during long-term drought period. In general, NEE was relatively low compared to other forest ecosystems. A good relationship was found between GPP and LE. Our data show that the inter-annual differences in NEE of the maquis ecosystem depend mainly on seasonal climate rather than on mean annual air temperature or precipitation. In addition, extreme weather events can also contribute to NEE inter-annual variability.

Spano, D.; Sirca, C.; Marras, S.; Carta, M.; Zara, P.; Arca, A.; Duce, P.

2011-12-01