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Last update: November 12, 2013.
1

Spectral difference analysis and airborne imaging classification for citrus greening infected trees  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus greening, also called Huanglongbing (HLB), became a devastating disease spread through citrus groves in Florida, since it was first found in 2005. Multispectral (MS) and hyperspectral (HS) airborne images of citrus groves in Florida were acquired to detect citrus greening infected trees in 20...

2

Factors affecting infection of citrus with Xanthomonas axonopodis pv citri.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Xanthomonas axonopodis pv citri (Xac) causes citrus canker and is now considered endemic in Florida. Factors affecting dispersal and infection of the bacteria need to be understood to help optimize disease management strategies. Wind (0-18 m/sec) was simulated outdoors using a fan to study infection...

3

Penicillium digitatum Suppresses Production of Hydrogen Peroxide in Host Tissue During Infection of Citrus Fruit  

Microsoft Academic Search

Macarisin, D., Cohen, L., Eick, A., Rafael, G., Belausov, E., Wisniewski, M., and Droby, S. 2007. Penicillium digitatum suppresses production of hydrogen peroxide in host tissue during infection of citrus fruit. Phytopathology 97:1491-1500. During the infection of citrus fruit by Penicillium digitatum there is little evidence of a host defense response. This suggests that P. digitatum has the ability to

D. Macarisin; L. Cohen; A. Eick; G. Rafael; E. Belausov; M. Wisniewski; S. Droby

2007-01-01

4

Quantitative Distribution of Candidatus Liberibacter asiaticus in Citrus Plants and Fruits Infected by Citrus Huanglongbing  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus huanglongbing (HLB), or greening disease, is caused by any of three non culturable Gram-negative bacteria belonging to Candidatus Liberibacter spp. The pathogens are transmitted by citrus psyllids to all commercial varieties of citrus. The diseases are lethal and have recently become widespr...

5

Response of Sweet Orange ( Citrus sinensis ) to ‘ Candidatus Liberibacter asiaticus’ Infection: Microscopy and Microarray Analyses  

Microsoft Academic Search

Kim, J.-S., Sagaram, U. S., Burns, J. K., Li, J.-L., and Wang, N. 2009. Response of sweet orange (Citrus sinensis) to 'Candidatus Liberibacter asiaticus' infection: Microscopy and microarray analyses. Phytopathology 99:50-57. Citrus greening or huanglongbing (HLB) is a devastating disease of citrus. HLB is associated with the phloem-limited fastidious prokaryotic ?-proteobacterium 'Candidatus Liberibacter spp.' In this report, we used sweet

Jeong-Soon Kim; Uma Shankar Sagaram; Jacqueline K. Burns; Jian-Liang Li; Nian Wang

2009-01-01

6

Near-Infrared Spectroscopy for discrimination of huanglongbing-infected citrus leaves from uninfected leaves  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus greening, also called Huanglongbing (HLB) or yellow dragon disease, is one of the more serious diseases of citrus and is a threat to the U.S. industry. An infected tree produces fruit that is unsuitable for sale as fresh fruit or for juice. The only definitive method of diagnosis of trees su...

7

PURIFICATION OF VIRUS-LIKE PARTICLES FROM CITRUS CHLOROTIC DWARF INFECTED CITRUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus chlorotic dwarf (CCD) is a new disease of citrus having been found in Turkey in the mid 1980s. Disease symptoms in the field consist of chlorotic leaf patterns, crinkling, leaf distortion, shoot malformation and stunting in young trees. CCD is vectored by the bayberry whitefly and is graft ...

8

Simultaneous determination of nickel, lead, zinc, and copper in citrus leaves and rice flour by liquid chromatography with hexamethylenedithiocarbamate extraction  

SciTech Connect

Reversed-phase liquid chromatography followed by solvent extraction with hexamethyleneammonium hexamethylenedithiocarbamate (HMA-HMDC) was carried out to determine Ni, Pb, Zn, and Cu in standard reference citrus leaves and rice flour. These samples (250 mg) were ashed with nitric acid and perchloric acid. The metals in the ash were extracted into chloroform as HMDC chelates which were then separated on a C 18 column and monitored at 260 nm. The microgram per gram levels of Ni, Pb, Zn, and Cu in the standard biological materials were simultaneously determined within 25 min. 22 references, 3 figures, 1 table.

Ichinoki, S.; Yamazaki, M.

1985-10-01

9

Detection and estimation of Citrus Tristeza Virus infection rates based on Elisa Assays of packing house fruit samples  

Microsoft Academic Search

Enzyme-linked immunosorbent assay (ELISA) proved to be a sensitive detector for citrus tristeza virus (CTV) in orange fruits\\u000a (Citrus sinensis (L.) Osbeck). Samples of five fruits were taken from 350-kg packing house containers and tested by ELISA to predict the infection\\u000a rate of CTV in two infected orange groves. The predicted infection rates, 1% and 11%, were in reasonable agreement

M. Bar-Joseph; J. M. Sacks; S. M. Garnsey

1978-01-01

10

The Influence of Glomus mosseae on Tylenchulus semipenetrans-Infected and Uninfected Citrus limon Seedlings.  

PubMed

Greenhouse studies have shown that when rough lemon (Citrus limon) seedlings infected with TyIenchulus semipenetrans were transplanted into soil infested with Glomus mosseae, the mycorrhizal fungus infection increased seedling growth compared to nonntycorrhizal seedlings. Tylenchulus semipenetrans significantly suppressed seedling growth below that of mycorrhizal seedlings. Histological observations of nematode-free mycorrhizal roots showed that hyphae penetrated the epidermis and invaded the cortex, giving rise to arbuscules and vesicles. Nematode infection sites in T. semipenetrans-infected roots grown in soil infested with G. mosseae did not show evidence of vesicle development in the cortex but did show arbuscule development. PMID:19300642

O'Bannon, J H; Inserra, R N; Nemec, S; Vovlas, N

1979-07-01

11

Heat treatment eliminates 'Candidatus Liberibacter asiaticus' from infected citrus trees under controlled conditions.  

PubMed

Huanglongbing (HLB) is one of the most destructive diseases of citrus worldwide. The three known causal agents of HLB are species of ?-proteobacteria: 'Candidatus Liberibacter asiaticus', 'Ca. L. africanus', and 'Ca. L. americanus'. Previous studies have found distinct variations in temperature sensitivity and tolerance among these species. Here, we describe the use of controlled heat treatments to cure HLB caused by 'Ca. L. asiaticus', the most prevalent and heat-tolerant species. Using temperature-controlled growth chambers, we evaluated the time duration and temperature required to suppress or eliminate the 'Ca. L. asiaticus' bacterium in citrus, using various temperature treatments for time periods ranging from 2 days to 4 months. Results of quantitative polymerase chain reaction (qPCR) after treatment illustrate significant decreases in the 'Ca. L. asiaticus' bacterial titer, combined with healthy vigorous growth by all surviving trees. Repeated qPCR testing confirmed that previously infected, heat-treated plants showed no detectable levels of 'Ca. L. asiaticus', while untreated control plants remained highly infected. Continuous thermal exposure to 40 to 42°C for a minimum of 48 h was sufficient to significantly reduce titer or eliminate 'Ca. L. asiaticus' bacteria entirely in HLB-affected citrus seedlings. This method may be useful for the control of 'Ca. Liberibacter'-infected plants in nursery and greenhouse settings. PMID:23035631

Hoffman, Michele T; Doud, Melissa S; Williams, Lisa; Zhang, Mu-Qing; Ding, Fang; Stover, Ed; Hall, David; Zhang, Shouan; Jones, Lisa; Gooch, Mark; Fleites, Laura; Dixon, Wayne; Gabriel, Dean; Duan, Yong-Ping

2013-01-01

12

Metabolomic analysis of citrus infection by 'Candidatus Liberibacter' reveals insight into pathogenicity.  

PubMed

Huanglongbing (HLB), considered the most serious citrus disease in the world, is associated with the nonculturable bacterium 'Candidatus Liberibacter asiaticus' (Las). Infection of citrus by this pathogen leads to reduced plant vigor and productivity, ultimately resulting in death of the infected tree. It can take up to two years following initial infection before outward symptoms become apparent, making detection difficult. The existing knowledge gap in our understanding of Las and its pathogenesis leading to HLB has stymied development of treatments and methods to mitigate the pathogen's influence. To evaluate the influence of Las on fruit quality in both symptomatic and asymptomatic fruit, and gain further insight into the pathogenesis of the disease, a 1H NMR metabolomics investigation, complemented with physicochemical and analyte-specific analyses, was undertaken. Comparison of the juice obtained from oranges gathered from Las+ (symptomatic and asymptomatic) and Las- (healthy) trees revealed significant differences in the concentrations of sugars, amino and organic acids, limonin glucoside, and limonin. This study demonstrates differing metabolic profiles in the juice of oranges from Las+ and Las- and proposes how Las may be able to evade citrus defense responses. PMID:22698301

Slisz, Anne M; Breksa, Andrew P; Mishchuk, Darya O; McCollum, Greg; Slupsky, Carolyn M

2012-07-02

13

Spatial Pattern Analysis of Citrus Canker-Infected Plantings in S?o Paulo, Brazil, and Augmentation of Infection Elicited by the Asian Leafminer  

Microsoft Academic Search

Gottwald, T. R., Bassanezi, R. B., Amorim, L., and Bergamin-Filho, A. 2007. Spatial pattern analysis of citrus canker-infected plantings in São Paulo, Brazil, and augmentation of infection elicited by the Asian leafminer. Phytopathology 97:674-683. Eradication of Asiatic citrus canker (ACC) has become increasingly difficult over the last decade, following the introduction of the Asian leafminer into Brazil and Florida, which

T. R. Gottwald; R. B. Bassanezi; L. Amorim; A. Bergamin-Filho

2007-01-01

14

Transcriptional and Microscopic Analyses of Citrus Stem and Root Responses to Candidatus Liberibacter asiaticus Infection  

PubMed Central

Huanglongbing (HLB) is the most destructive disease that affects citrus worldwide. The disease has been associated with Candidatus Liberibacter. HLB diseased citrus plants develop a multitude of symptoms including zinc and copper deficiencies, blotchy mottle, corky veins, stunting, and twig dieback. Ca. L. asiaticus infection also seriously affects the roots. Previous study focused on gene expression of leaves and fruit to Ca. L. asiaticus infection. In this study, we compared the gene expression levels of stems and roots of healthy plants with those in Ca. L. asiaticus infected plants using microarrays. Affymetrix microarray analysis showed a total of 988 genes were significantly altered in expression, of which 885 were in the stems, and 111 in the roots. Of these, 551 and 56 were up-regulated, while 334 and 55 were down-regulated in the stem and root samples of HLB diseased trees compared to healthy plants, respectively. Dramatic differences in the transcriptional responses were observed between citrus stems and roots to Ca. L. asiaticus infection, with only 8 genes affected in both the roots and stems. The affected genes are involved in diverse cellular functions, including carbohydrate metabolism, cell wall biogenesis, biotic and abiotic stress responses, signaling and transcriptional factors, transportation, cell organization, protein modification and degradation, development, hormone signaling, metal handling, and redox. Microscopy analysis showed the depletion of starch in the roots of the infected plants but not in healthy plants. Collapse and thickening of cell walls were observed in HLB affected roots, but not as severe as in the stems. This study provides insight into the host response of the stems and roots to Ca. L. asiaticus infection.

Aritua, Valente; Achor, Diann; Gmitter, Frederick G.; Albrigo, Gene; Wang, Nian

2013-01-01

15

Transcriptional and Microscopic Analyses of Citrus Stem and Root Responses to Candidatus Liberibacter asiaticus Infection.  

PubMed

Huanglongbing (HLB) is the most destructive disease that affects citrus worldwide. The disease has been associated with Candidatus Liberibacter. HLB diseased citrus plants develop a multitude of symptoms including zinc and copper deficiencies, blotchy mottle, corky veins, stunting, and twig dieback. Ca. L. asiaticus infection also seriously affects the roots. Previous study focused on gene expression of leaves and fruit to Ca. L. asiaticus infection. In this study, we compared the gene expression levels of stems and roots of healthy plants with those in Ca. L. asiaticus infected plants using microarrays. Affymetrix microarray analysis showed a total of 988 genes were significantly altered in expression, of which 885 were in the stems, and 111 in the roots. Of these, 551 and 56 were up-regulated, while 334 and 55 were down-regulated in the stem and root samples of HLB diseased trees compared to healthy plants, respectively. Dramatic differences in the transcriptional responses were observed between citrus stems and roots to Ca. L. asiaticus infection, with only 8 genes affected in both the roots and stems. The affected genes are involved in diverse cellular functions, including carbohydrate metabolism, cell wall biogenesis, biotic and abiotic stress responses, signaling and transcriptional factors, transportation, cell organization, protein modification and degradation, development, hormone signaling, metal handling, and redox. Microscopy analysis showed the depletion of starch in the roots of the infected plants but not in healthy plants. Collapse and thickening of cell walls were observed in HLB affected roots, but not as severe as in the stems. This study provides insight into the host response of the stems and roots to Ca. L. asiaticus infection. PMID:24058486

Aritua, Valente; Achor, Diann; Gmitter, Frederick G; Albrigo, Gene; Wang, Nian

2013-09-13

16

Transcriptional response of susceptible and tolerant citrus to infection with Candidatus Liberibacter asiaticus.  

PubMed

Candidatus Liberibacter asiaticus (Las), a non-culturable phloem-limited bacterium, is the suspected causal agent of huanglongbing (HLB) in Florida. HLB is one of the most devastating diseases of citrus and no resistant cultivars have been identified to date, though tolerance has been observed in the genus Poncirus and some of its hybrids. This study compares transcriptional changes in tolerant US-897 (Citrus reticulata Blanco×Poncirus trifoliata L. Raf.) and susceptible 'Cleopatra' mandarin (C. reticulata) seedlings in response to infection with Las using the Affymetrix GeneChip citrus array, with the main objective of identifying genes associated with tolerance to HLB. Microarray analysis identified 326 genes which were significantly upregulated by at least 4-fold in the susceptible genotype, compared with only 17 genes in US-897. Exclusively upregulated in US-897 was a gene for a 2-oxoglutarate (2OG) and Fe(II)-dependant oxygenase, an important enzyme involved in the biosynthesis of plant secondary metabolites. More than eight hundred genes were expressed at much higher levels in US-897 independent of infection with Las. Among these, genes for a constitutive disease resistance protein (CDR1) were notable. The possible involvement of these and other detected genes in tolerance to HLB and their possible use for biotechnology are discussed. PMID:22325873

Albrecht, Ute; Bowman, Kim D

2011-10-01

17

Effect of Liberibacter infection (Huanglongbing or "greening" disease) of citrus on orange juice flavor quality by sensory evaluation  

Technology Transfer Automated Retrieval System (TEKTRAN)

There have been some anecdotal reports that Liberibacter asiaticus [(+) Las] infection of citrus trees, recently introduced in Florida, imparts off flavor to orange juice. It is of interest to the industry to know how much Liberibacter infection affects juice quality with respect to variety, maturit...

18

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

19

Processess involved in the dispersal of Xanthomonas citri pv. citri from canker-infected citrus canopies, and in the infection of citrus foliage  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus canker (Xanthomonas citri subsp. citri, Xcc) is now considered endemic in Florida, and epidemics result in yield loss and market penalties both in Florida and elsewhere, where the pathogen occurs and susceptible citrus is cultivated. The bacterium is dispersed in rain splash, and storms with...

20

The effects of ‘Candidatus Liberibacter asiaticus’ infection on the protein expression profiles and nutrient status of Citrus plants  

Technology Transfer Automated Retrieval System (TEKTRAN)

Huanglongbing (HLB) is a destructive disease of citrus plants causing significant yield loss within 4-6 years of initial infection. The etiology of HLB worldwide is associated with three insect-transmissible phloem-limited members of the bacterial group ‘Candidatus Liberibacter spp’, prevalently ‘Ca...

21

APHID TRANSMISSION OF STEM PITTING CITRUS TRISTEZA VIRUS FROM MIXED VIRUS INFECTIONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus tristeza virus (CTV), a phloem-limited closterovirus, contains a single-stranded, 20- kb RNA. Numerous isolates of the virus exist which produce a variety of symptoms in various citrus hosts. One of these symptoms is stem pitting (SP). SP does not occur in all citrus hosts but may cause lo...

22

First Report of Dodder Transmission of Huanglongbing from Naturally Infected Murraya paniculata to Citrus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Huanglongbing (HLB) or “greening” disease of citrus is caused by phloem-limited, uncultured bacteria in the genus “Candidatus Liberibacter”. HLB is one of the most destructive diseases of citrus worldwide and is considered so dangerous to a U.S. citrus production that the USDA has listed “Ca. Liberi...

23

Expression profiling of common and specific defense responses of rice to Magnaporthe oryzae infection using deep sequencing technologies  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rice blast caused by Magnaporthe oryzae is a serious disease in rice production. Wild type Nipponbare and transgenic rice plants (carrying the Pi9 blast resistance gene) were challenged with the rice blast strain KJ201 to identify the early, mid and late host responses to M. oryzae infection at the ...

24

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

25

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

26

Transmission of Rice Black-Streaked Dwarf Virus from Frozen Infected Leaves to Healthy Rice Plants by Small Brown Planthopper ( Laodelphax striatellus)  

Microsoft Academic Search

In order to preserve virus for identifying the resistance of rice varieties against rice black-streaked dwarf disease, a simple and reliable method was developed, through which virus-free small brown planthopper (SBPH) acquired rice black-streaked dwarf virus (RBSDV) from frozen infected leaves and the virus was transmitted to healthy rice plants. The experimental results showed that SBPH could obtain RBSDV from

Tong ZHOU; Li-juan WU; Ying WANG; Zhao-bang CHENG; Ying-hua JI; Yong-jian FAN; Yi-jun ZHOU

2011-01-01

27

RL-SAGE and microarray analysis of the rice defense transcriptome after Rhizoctonia solani infection  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sheath blight caused by the fungal pathogen Rhizoctonia solani is an emerging problem in rice production worldwide. To elucidate the molecular basis of rice defense to the pathogen, RNA isolated from R. solani-infected leaves of Jasmine 85 was used for both RL-SAGE library construction and microarra...

28

Rice body formation without rheumatic disease or tuberculosis infection: a case report and literature review.  

PubMed

Rice body formation is an uncommon inflammatory disorder associated with systemic disorders such as rheumatoid arthritis and tuberculosis infection. The pathophysiology of rice bodies is poorly understood. We describe a case of rice body formation in a 51-year-old male who presented with pain and swelling of the left wrist. The patient had no previous history of rheumatic disease, joint trauma, or infectious disease. He underwent a radical tenosynovectomy and had immediate improvement of symptoms. Despite extensive evaluation, the etiology of the rice bodies could not be identified. An increasing number of case reports have described rice body formation without a known cause suggesting an alternative, unidentified method of pathogenesis. We describe a unique case of rice body formation and a review of the literature with emphasis on theories of pathogenesis, diagnostic methods, and treatment. PMID:22941257

Forse, Catherine L; Mucha, Bernardo L; Santos, M Lauren Zabala; Ongcapin, Emelie H

2012-09-02

29

Global gene expression of Poncirus trifoliata, Citrus sunki and their hybrids under infection of Phytophthora parasitica  

Microsoft Academic Search

BACKGROUND: Gummosis and root rot caused by Phytophthora are among the most economically important diseases in citrus. Four F1 resistant hybrids (Pool R), and four F1 susceptible hybrids (Pool S) to P. parasitica, were selected from a cross between susceptible Citrus sunki and resistant Poncirus trifoliata cv. Rubidoux. We investigated gene expression in pools of four resistant and four susceptible

Leonardo P Boava; Mariângela Cristofani-Yaly; Valéria S Mafra; Karen Kubo; Luciano T Kishi; Marco A Takita; Marcelo Ribeiro-Alves; Marcos A Machado

2011-01-01

30

Callose deposition in the phloem plasmodesmata and inhibition of phloem transport in citrus leaves infected with "Candidatus Liberibacter asiaticus".  

PubMed

Huanglongbing (HLB) is a destructive disease of citrus trees caused by phloem-limited bacteria, Candidatus Liberibacter spp. One of the early microscopic manifestations of HLB is excessive starch accumulation in leaf chloroplasts. We hypothesize that the causative bacteria in the phloem may intervene photoassimilate export, causing the starch to over-accumulate. We examined citrus leaf phloem cells by microscopy methods to characterize plant responses to Liberibacter infection and the contribution of these responses to the pathogenicity of HLB. Plasmodesmata pore units (PPUs) connecting companion cells and sieve elements were stained with a callose-specific dye in the Liberibacter-infected leaf phloem cells; callose accumulated around PPUs before starch began to accumulate in the chloroplasts. When examined by transmission electron microscopy, PPUs with abnormally large callose deposits were more abundant in the Liberibacter-infected samples than in the uninfected samples. We demonstrated an impairment of symplastic dye movement into the vascular tissue and delayed photoassimilate export in the Liberibacter-infected leaves. Liberibacter infection was also linked to callose deposition in the sieve plates, which effectively reduced the sizes of sieve pores. Our results indicate that Liberibacter infection is accompanied by callose deposition in PPUs and sieve pores of the sieve tubes and suggest that the phloem plugging by callose inhibits phloem transport, contributing to the development of HLB symptoms. PMID:21874517

Koh, Eun-Ji; Zhou, Lijuan; Williams, Donna S; Park, Jiyoung; Ding, Ningyuan; Duan, Yong-Ping; Kang, Byung-Ho

2011-08-28

31

Study on Citrus Response to Huanglongbing Highlights a Down-Regulation of Defense-Related Proteins in Lemon Plants Upon 'Ca. Liberibacter asiaticus' Infection  

PubMed Central

Citrus huanglongbing (HLB) is a highly destructive disease of citrus presumably caused by ‘Candidatus Liberibacter asiaticus’ (Las), a gram-negative, insect-transmitted, phloem-limited ?-proteobacterium. Although almost all citrus plants are susceptible to HLB, reports have shown reduced susceptibility to Las infection in lemon (Citruslimon) plants. The aim of this study is to identify intra-species specific molecular mechanisms associated with Las-induced responses in lemon plants. To achieve this, comparative 2-DE and mass spectrometry, in addition to Inductively Coupled Plasma Spectroscopy (ICPS) analyses, were applied to investigate differences in protein accumulation and the concentrations of cationic elements in leaves of healthy and Las-infected lemon plants. Results showed a differential accumulation of 27 proteins, including an increase in accumulation of starch synthase but decrease in the production of photosynthesis-related proteins in Las-infected lemon plants compared to healthy plants. Furthermore, there was a 6% increase (P > 0.05) in K concentration in leaves of lemon plants upon Las infection, which support results from previous studies and might represent a common response pattern of citrus plants to Las infection. Interestingly, contrary to reports from prior studies, this study showed a general reduction in the production of defense-related pathogen-response proteins but a 128% increase in Zn concentration in lemon plants in response to Las infection. Taken together, this study sheds light on general and intra-species specific responses associated with the response of citrus plants to Las.

Nwugo, Chika C.; Duan, Yongping; Lin, Hong

2013-01-01

32

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

33

Lack of effect of feeding citrus by-products in reducing salmonella in experimentally infected weanling pigs.  

PubMed

The objective of the current research was to determine if feeding the citrus by-products(D) -limonene (DL) and citrus molasses would reduce the concentration and prevalence of Salmonella in weanling pigs experimentally infected with Salmonella Typhimurium. Twenty crossbred weanling pigs (average body weight [BW], 19.9 kg) were randomly assigned to one of four treatments: control, low-dose DL (1.5 ml/kg of BW per day), high-dose DL (3.0 ml/kg of BW per day), and citrus molasses (0.05 kg/kg of BW per day). Treatments were administered in the feed (twice daily) for 7 days, with one-half of the dose administered at each feeding. Fecal samples were collected twice daily (prior to administration of treatment) and cultured for quantitative and qualitative determination of the challenge strain of Salmonella. Upon termination of the study, pigs were euthanized and tissues from the stomach, ileum, cecum, spiral colon, and rectum, as well as luminal contents, were collected. In addition, the popliteal and ileocecal lymph nodes and liver, spleen, and tonsil tissue were collected for qualitative Salmonella culture. No significant treatment differences (P > 0.05) were observed among treatments for fecal concentration or prevalence of Salmonella throughout the 7-day collection period. Likewise, no treatment differences (P > 0.05) were observed for any of the tissue or luminal content samples collected. Salmonella was not cultured from the muscle-bound popliteal lymph node but was cultured from the mesenteric ileocecal lymph nodes. While there were no effects in the current experiment, future research may examine the effect of a lower challenge dose and/or different administration (dose or duration) of the citrus by-products. PMID:22410233

Farrow, R L; Edrington, T S; Krueger, N A; Genovese, K J; Callaway, T R; Anderson, R C; Nisbet, D J

2012-03-01

34

Observations on the Foliar Nematode, Aphelenchoides besseyi, Infecting Tuberose and Rice in India.  

PubMed

The foliar nematode Aphelenchoides besseyi causes white tip disease in rice (Oryza sativa L.) and floral malady in tuberose (Polianthes tuberosa L.). This nematode is widely distributed in the rice fields of many states of India, including West Bengal (WB), Andhra Pradesh (AP), Madhya Pradesh (MP) and Gujarat (GT). In order to generate information on intraspecific variations of A. besseyi as well as to confirm the identity of the nematode species infecting these important crops, morphological observation was undertaken of A. besseyi isolated from tuberose and rice from WB and rice from AP, MP and GT. The molecular study was only done for rice and tuberose populations from AP and WB. The variations were observed among the populations in the tail, esophageal and anterior regions, including the occurrence of four as well as six lateral lines in the lateral fields. The morphometrics of observed populations showed variations and those could be regarded as a consequence of host-induced or geographical variations. PCR amplification of the rDNA ITS 1 and 2 region of rice (AP) and tuberose (WB) populations of A. besseyi generated one fragment of approximately 830 bp, and the size of the ITS region was 788 bp and 791 bp for tuberose and rice population, respectively. Alignment of the two sequences showed almost 100% similarity. Blast analysis revealed a very high level of similarity of both the Indian strains to a Russian population. The Indian and Russian strains could be differentiated using restriction enzyme Bccl. Host tests revealed that rice (cv. IET 4094), oat (cv. OS-6) and teosinte (cv. TL-1) showed a typical distortion due to the infection of A. besseyi. Five germplasm lines of oat showed no infection of the nematode under field conditions. Local cultivars of onion, maize, chrysanthemum, gladiolus, and Sorghum halepense were also not infected by A. besseyi. PMID:23482906

Khan, Matiyar R; Handoo, Zafar A; Rao, Uma; Rao, S B; Prasad, J S

2012-12-01

35

Observations on the Foliar Nematode, Aphelenchoides besseyi, Infecting Tuberose and Rice in India  

PubMed Central

The foliar nematode Aphelenchoides besseyi causes white tip disease in rice (Oryza sativa L.) and floral malady in tuberose (Polianthes tuberosa L.). This nematode is widely distributed in the rice fields of many states of India, including West Bengal (WB), Andhra Pradesh (AP), Madhya Pradesh (MP) and Gujarat (GT). In order to generate information on intraspecific variations of A. besseyi as well as to confirm the identity of the nematode species infecting these important crops, morphological observation was undertaken of A. besseyi isolated from tuberose and rice from WB and rice from AP, MP and GT. The molecular study was only done for rice and tuberose populations from AP and WB. The variations were observed among the populations in the tail, esophageal and anterior regions, including the occurrence of four as well as six lateral lines in the lateral fields. The morphometrics of observed populations showed variations and those could be regarded as a consequence of host-induced or geographical variations. PCR amplification of the rDNA ITS 1 and 2 region of rice (AP) and tuberose (WB) populations of A. besseyi generated one fragment of approximately 830 bp, and the size of the ITS region was 788 bp and 791 bp for tuberose and rice population, respectively. Alignment of the two sequences showed almost 100% similarity. Blast analysis revealed a very high level of similarity of both the Indian strains to a Russian population. The Indian and Russian strains could be differentiated using restriction enzyme Bccl. Host tests revealed that rice (cv. IET 4094), oat (cv. OS-6) and teosinte (cv. TL-1) showed a typical distortion due to the infection of A. besseyi. Five germplasm lines of oat showed no infection of the nematode under field conditions. Local cultivars of onion, maize, chrysanthemum, gladiolus, and Sorghum halepense were also not infected by A. besseyi.

Khan, Matiyar R.; Handoo, Zafar A.; Rao, Uma; Rao, S. B.; Prasad, J. S.

2012-01-01

36

Effect of glyphosate on tryptamine production and Sekiguchi lesion formation in rice infected with Magnaporthe grisea  

Microsoft Academic Search

When exposed to light, the Sekiguchi lesion (sl) rice mutant has an enhanced resistance to Magnaporthe grisea infection responsible for Sekiguchi lesion formation and tryptamine accumulation. Glyphosate [N-(phosphonomethyl) glycine] pretreatment suppressed Sekiguchi lesion formation and tryptamine accumulation in the sl mutant after M. grisea infection even under light. This inhibition by glyphosate was blocked by the supply of exogenous tryptophan,

Atsuko Imaoka; Makoto Ueno; Junichi Kihara; Sakae Arase

2008-01-01

37

Processes involved in the dispersal of Xanthomonas citri pv. citri from canker-infectd citrus canopies, and in the infection of citrus foliage  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus canker (Xanthomonas citri subsp. citri, Xcc) is now considered endemic in Florida, and epidemics result in yield loss and market penalties both in Florida, and elsewhere where the pathogen occurs, and susceptible citrus is cultivated. The bacterium is dispersed in rain splash, and storms wit...

38

G Protein Regulation of Disease Resistance During Infection of Rice with Rice Blast Fungus  

NSDL National Science Digital Library

When the effects of specific pathogen-produced elicitor compounds on plant cells are recognized by specific plant resistance (R) gene products, a local defense response called the hypersensitive response is triggered. Production of reactive oxygen species (ROS) and induction of defense genes are components of this response. In rice cultivars harboring null mutations in the G protein α subunit, RGA1, ROS production and defense gene induction by the rice blast fungus Magnaporthe grisea and its sphingolipid elicitors are reduced or delayed. These results implicate heterotrimeric guanine nucleotide–binding proteins (G proteins) as important players in plant pathogen response.

Sarah M. Assmann (Penn State University;Biology Department REV)

2005-11-15

39

Detection of citrus canker in citrus plants using laser induced fluorescence spectroscopy  

Microsoft Academic Search

Citrus canker is a serious disease caused by Xanthomonas citri subsp. citri bacteria, which infects citrus plants (Citrus spp.) leading to a large economic loss in citrus production worldwide. In Brazil citrus canker control is done by an official\\u000a eradication campaign, therefore early detection of such disease is important to prevent greater economic losses. However,\\u000a detection is difficult and so

Emery C. Lins; José Belasque; Luis G. Marcassa

2009-01-01

40

Transcriptional response of susceptible and tolerant citrus to infection with Candidatus Liberibacter asiaticus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Candidatus Liberibacter asiaticus (Las), a non-culturable phloem-limited bacterium, is the suspected causal agent of Huanglongbing (HLB) in Florida. HLB is one of the most devastating diseases of citrus and no resistant cultivars have been identified to date, though tolerance has been observed in t...

41

Bacterial diversity analysis of Huanglongbing pathogen-infected citrus, using PhyloChip and 16S rRNA gene clone library sequencing  

SciTech Connect

The bacterial diversity associated with citrus leaf midribs was characterized 1 from citrus groves that contained the Huanglongbing (HLB) pathogen, which has yet to be cultivated in vitro. We employed a combination of high-density phylogenetic 16S rDNA microarray and 16S rDNA clone library sequencing to determine the microbial community composition of symptomatic and asymptomatic citrus midribs. Our results revealed that citrus leaf midribs can support a diversity of microbes. PhyloChip analysis indicated that 47 orders of bacteria from 15 phyla were present in the citrus leaf midribs while 20 orders from phyla were observed with the cloning and sequencing method. PhyloChip arrays indicated that nine taxa were significantly more abundant in symptomatic midribs compared to asymptomatic midribs. Candidatus Liberibacter asiaticus (Las) was detected at a very low level in asymptomatic plants, but was over 200 times more abundant in symptomatic plants. The PhyloChip analysis was further verified by sequencing 16S rDNA clone libraries, which indicated the dominance of Las in symptomatic leaves. These data implicate Las as the pathogen responsible for HLB disease. Citrus is the most important commercial fruit crop in Florida. In recent years, citrus Huanglongbing (HLB), also called citrus greening, has severely affected Florida's citrus production and hence has drawn an enormous amount of attention. HLB is one of the most devastating diseases of citrus (6,13), characterized by blotchy mottling with green islands on leaves, as well as stunting, fruit decline, and small, lopsided fruits with poor coloration. The disease tends to be associated with a phloem-limited fastidious {alpha}-proteobacterium given a provisional Candidatus status (Candidatus Liberobacter spp. later changed to Candidatus Liberibacter spp.) in nomenclature (18,25,34). Previous studies indicate that HLB infection causes disorder in the phloem and severely impairs the translocation of assimilates in host plants (5,27,40). Tatineni and colleagues discovered that the HLB bacteria were unevenly distributed in phloem of bark tissue, vascular tissue of the leaf midrib, roots, and different floral and fruit parts (43). Unsuccessful attempts in culturing the pathogen are notably hampering efforts to understand its biology and pathogenesis mechanism. Using a modified Koch's Postulates approach, Jagoueix and colleagues were able to re-infect periwinkle plants from a mixed microbial community harvested from HLB diseased plants (25). Emergence of the disease in otherwise healthy plants led to the conclusion that HLB was associated with Candidatus Liberibacter sp. based on its 16S rDNA sequence (18,25). Currently, three species of the pathogen are recognized from trees with HLB disease based on 16S rDNA sequence: Ca. Liberibacter asiaticus (Las), Ca. Liberibacter africanus (Laf), and Ca. Liberibacter americanus (Lam); Las is the most prevalent species among HLB diseased trees (5,12,18,25,44). Las is naturally transmitted to citrus by the psyllid, Diaphorina citri Kuwayama, and can be artificially transmitted by grafting from citrus to citrus and dodder (Cuscuta campestris) to periwinkle (Catharanthus roseus) or tobacco (Nicotiana tabacum Xanthi) (5). Based on current research regarding the associations of Liberibacter in planta there is not enough evidence to implicate Liberibacter as the definitive causal agent of HLB disease due to its resistance to cultivation in vitro. It is possible that HLB disease may be the result of complex etiology where Liberibacter interacts with other endophytic bacteria. However, there is not enough evidence regarding its association(s) in planta to make this conclusion, nor is it known whether associated microbial communities play a role in expression of pathogenic traits. The main objective of the study was to test the hypothesis that other bacteria besides Ca. Liberibacter spp. are associated with citrus greening disease. The differences between the relative abundance, species richness and phylogenetic diversity of the microbial communitie

Shankar Sagaram, U.; DeAngelis, K.M.; Trivedi, P.; Andersen, G.L.; Lu, S.-E.; Wang, N.

2009-03-01

42

A transcriptomic approach highlights induction of secondary metabolism in citrus fruit in response to Penicillium digitatum infection  

Microsoft Academic Search

BACKGROUND: Postharvest losses of citrus fruit due to green mold decay, caused by the fungus Penicillium digitaum, have a considerable economic impact. However, little is known about the molecular processes underlying the response of citrus fruit to P. digitatum. RESULTS: Here we describe the construction of a subtracted cDNA library enriched in citrus genes preferentially expressed in response to pathogen

Luis González-Candelas; Santiago Alamar; Paloma Sánchez-Torres; Lorenzo Zacarías; Jose F Marcos

2010-01-01

43

INFECTION OF WAMPEE AND LEMON BY THE CITRUS HUANGLONGBING PATHOGEN (CANDIDATUS LIBERIBACTER ASIATICUS) IN CHINA  

Microsoft Academic Search

SUMMARY Single-step and nested polymerase chain reactions (PCR) were used to determine the presence of Candida- tus Liberibacter asiaticus, the phloem-limited bacterial pathogen of Huanglongbing (HLB), in leaves of wampee (Clausena lansium (Lour.) Skeels), lemon (Cit- rus limon (L.) Burm.) and several other citrus species. Specific PCR products were obtained when single-step PCR and nested PCR were used to analyze

F. Ding; G. Wang; G. Yi; Y. Zhong; J. Zeng; B. Zhou

2005-01-01

44

Citrus Canker: The Pathogen and Its Impact  

NSDL National Science Digital Library

This resource is a review article about the Citrus Canker, an introduced plant disease. The article contains detailed background and overview and includes information on (1) Citrus Canker strain diversity, identification, diagnosis and characterization; (2) the symptoms and infection Process; (3) the epidemiology; (4) the management for prevention and control of Citrus Canker; (5) and the social, political, and legal ramifications of regulatory policy.

Tim R. Gottwald (USDA;); James H. Graham (University of Florida;); Tim S. Schubert (Florida Department of Agriculture and Consumer Services;)

2002-08-12

45

Citrus phenylpropanoids and defence against pathogens. Part II: gene expression and metabolite accumulation in the response of fruits to Penicillium digitatum infection.  

PubMed

The effect of infection of Citrus sinensis (var. Navelina) fruits with Penicillium digitatum was studied at gene expression and metabolite levels. In this study, expression of genes involved in the phenylpropanoid pathway was studied in the flavedo (outer coloured part of the peel) and albedo (inner white part) in response to pathogen infection. Results of the time-course experiment showed that maximal expression of 10 out of 17 phenylpropanoid genes analysed occurred at 48h post-inoculation, when decay symptoms started to appear, and mRNA levels either kept constant or decreased after 72h post-inoculation. To further investigate the putative involvement of the phenylpropanoid pathway in the defence of citrus fruit, changes in the metabolic profile of both tissues infected with P. digitatum was studied by means of HPLC-PDA-FD. Metabolite accumulation levels along the time course suggest that flavanones, flavones, polymethoxylated flavones and scoparone are induced in citrus fruit in response to P. digitatum infection, although with different trends depending on the tissue. PMID:23017425

Ballester, Ana-Rosa; Teresa Lafuente, M; González-Candelas, Luis

2012-08-16

46

Gene expression in Citrus sinensis (L.) Osbeck following infection with the bacterial pathogen Candidatus Liberibacter asiaticus causing Huanglongbing in Florida  

Microsoft Academic Search

Huanglongbing (HLB) (=citrus greening) is a destructive disease of citrus which is caused by a fastidious, phloem-inhabiting bacterium of the genus Candidatus Liberibacter. Large-scale analysis of gene expression changes in ‘Valencia’ orange leaves were studied during the course of 19 weeks after inoculation with Ca. L. asiaticus using the Affymetrix GeneChip® citrus genome array to provide new insights into the

Ute Albrecht; Kim D. Bowman

2008-01-01

47

An NADPH-dependent genetic switch regulates plant infection by the rice blast fungus.  

PubMed

To cause rice blast disease, the fungus Magnaporthe oryzae breaches the tough outer cuticle of the rice leaf by using specialized infection structures called appressoria. These cells allow the fungus to invade the host plant and proliferate rapidly within leaf tissue. Here, we show that a unique NADPH-dependent genetic switch regulates plant infection in response to the changing nutritional and redox conditions encountered by the pathogen. The biosynthetic enzyme trehalose-6-phosphate synthase (Tps1) integrates control of glucose-6-phosphate metabolism and nitrogen source utilization by regulating the oxidative pentose phosphate pathway, the generation of NADPH, and the activity of nitrate reductase. We report that Tps1 directly binds to NADPH and, thereby, regulates a set of related transcriptional corepressors, comprising three proteins, Nmr1, Nmr2, and Nmr3, which can each bind NADP. Targeted deletion of any of the Nmr-encoding genes partially suppresses the nonpathogenic phenotype of a ?tps1 mutant. Tps1-dependent Nmr corepressors control the expression of a set of virulence-associated genes that are derepressed during appressorium-mediated plant infection. When considered together, these results suggest that initiation of rice blast disease by M. oryzae requires a regulatory mechanism involving an NADPH sensor protein, Tps1, a set of NADP-dependent transcriptional corepressors, and the nonconsuming interconversion of NADPH and NADP acting as signal transducer. PMID:21115813

Wilson, Richard A; Gibson, Robert P; Quispe, Cristian F; Littlechild, Jennifer A; Talbot, Nicholas J

2010-11-29

48

Callose deposition and inhibited symplastic transport in the phloem of citrus leaves infected with Candidatus Liberibacter asiaticus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Huanglongbing (HLB) is a lethal disease of citrus, damaging citrus agriculture worldwide. A phloem-limited, alpha proteobacterium, Candidatus Liberibacter asiaticus (Las) is associated with HLB in North America. We examined Lasinfected (Las+) leaf phloem cells by microscopy methods to characterize p...

49

Differential stylet penetration behaviors of two Aphis gossypii biotypes in relation to host or vector infection with Citrus tristeza virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus tristeza virus (CTV) is one of the most important citrus disease agents worldwide. The impact of CTV on American agriculture has been significant, affecting 50 million trees with economic losses of several hundred million dollars. In California, this virus is predominantly transmitted by tw...

50

Transcriptional responses and carbohydrate metabolism of citrus infected with Candidatus Liberibacter asiaticus, the causal agent of Huanglongbing in Florida  

Technology Transfer Automated Retrieval System (TEKTRAN)

Huanglongbing (HLB) is a devastating disease of citrus occurring in most citrus growing regions worldwide. It is caused by a phloem-limited, fastidious bacterium of the genus Candidatus Liberibacter, which is transmitted through insect vectors. HLB causes the decline of trees within few years afte...

51

Gene expression in Citrus sinensis (L.) Osbeck following infection with the bacterial pathogen Candidatus Liberibacter asiaticus causing Huanglongbing in Florida  

Technology Transfer Automated Retrieval System (TEKTRAN)

Hunglongbing (HLB) (=citrus greening) is a destructive disease of citrus which is caused by a fastidious, phloem-inhabiting bacterium of the genus Candidatus Liberibacter. Large-scale analysis of gene expression changes in ‘Valencia’ orange leaves were studied during the course of 19 weeks after in...

52

NADPH oxidases regulate septin-mediated cytoskeletal remodeling during plant infection by the rice blast fungus  

PubMed Central

The rice blast fungus Magnaporthe oryzae infects plants with a specialized cell called an appressorium, which uses turgor to drive a rigid penetration peg through the rice leaf cuticle. Here, we show that NADPH oxidases (Nox) are necessary for septin-mediated reorientation of the F-actin cytoskeleton to facilitate cuticle rupture and plant cell invasion. We report that the Nox2–NoxR complex spatially organizes a heteroligomeric septin ring at the appressorium pore, required for assembly of a toroidal F-actin network at the point of penetration peg emergence. Maintenance of the cortical F-actin network during plant infection independently requires Nox1, a second NADPH oxidase, which is necessary for penetration hypha elongation. Organization of F-actin in appressoria is disrupted by application of antioxidants, whereas latrunculin-mediated depolymerization of appressorial F-actin is competitively inhibited by reactive oxygen species, providing evidence that regulated synthesis of reactive oxygen species by fungal NADPH oxidases directly controls septin and F-actin dynamics.

Ryder, Lauren S.; Dagdas, Yasin F.; Mentlak, Thomas A.; Kershaw, Michael J.; Thornton, Christopher R.; Schuster, Martin; Chen, Jisheng; Wang, Zonghua; Talbot, Nicholas J.

2013-01-01

53

Current status of Citrus tristeza virus in Central California  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Lindcove Research and Extension Center (LREC), Exeter, CA has 51 ha of citrus and is the field site and screenhouses for the University of California Citrus Clonal Protection Program (CCPP). LREC maintains a zero tolerance of Citrus tristeza virus (CTV) infected trees to protect the CCPP and re...

54

Identification of defence-related genes expressed in coffee and citrus during infection by Xylella fastidiosa  

Microsoft Academic Search

One of the phytosanitary problems of coffee cultivation in Brazil is Coffee Leaf Scorch (CLS) disease, caused by the phytopathogenic\\u000a bacterium Xylella fastidiosa. Due to the economic importance of coffee to Brazil and the losses caused by X. fastidiosa, a cDNA library (RX1) was constructed using infected coffee stems. This library is one of the 37 coffee EST libraries constructed

Marcelo F. Carazzolle; Fernanda R. Rabello; Natália F. Martins; Alessandra A. de Souza; Alexandre M. do Amaral; Juliana Freitas-Astua; Gonçalo A. G. Pereira; Marcos A. Machado; Angela Mehta

55

Confirmation of the sequence of 'Candidatus Liberibacter asiaticus' and assessment of microbial diversity in Huanglongbing-infected citrus phloem using a metagenomic approach.  

PubMed

The citrus disease Huanglongbing (HLB) is highly destructive in many citrus-growing regions of the world. The putative causal agent of this disease, 'Candidatus Liberibacter asiaticus', is difficult to culture, and Koch's postulates have not yet been fulfilled. As a result, efforts have focused on obtaining the genome sequence of 'Ca. L. asiaticus' in order to give insight on the physiology of this organism. In this work, three next-generation high-throughput sequencing platforms, 454, Solexa, and SOLiD, were used to obtain metagenomic DNA sequences from phloem tissue of Florida citrus trees infected with HLB. A culture-independent, polymerase chain reaction (PCR)-independent analysis of 16S ribosomal RNA sequences showed that the only bacterium present within the phloem metagenome was 'Ca L. asiaticus'. No viral or viroid sequences were identified within the metagenome. By reference assembly, the phloem metagenome contained sequences that provided 26-fold coverage of the 'Ca. L. asiaticus' contigs in GenBank. By the same approach, phloem metagenomic data yielded less than 0.2-fold coverage of five other alphaproteobacterial genomes. Thus, phloem metagenomic DNA provided a PCR-independent means of verifying the presence of 'Ca L. asiaticus' in infected tissue and strongly suggests that no other disease agent was present in phloem. Analysis of these metagenomic data suggest that this approach has a detection limit of one 'Ca. Liberibacter' cell for every 52 phloem cells. The phloem sample sequenced here is estimated to have contained 1.7 'Ca. Liberibacter' cells per phloem cell. PMID:19888827

Tyler, Heather L; Roesch, Luiz F W; Gowda, Siddarame; Dawson, William O; Triplett, Eric W

2009-12-01

56

Nitric oxide generated by the rice blast fungus Magnaporthe oryzae drives plant infection.  

PubMed

Plant-derived nitric oxide (NO) triggers defence, priming the onset of the hypersensitive response and restricting pathogen ingress during incompatibility. However, little is known about the role of pathogen-produced NO during pre-infection development and infection. We sought evidence for NO production by the rice blast fungus during early infection. NO production was measured using fluorescence of DAR-4M and the role of NO assessed using NO scavengers. The synthesis of NO was investigated by targeted knockout of genes potentially involved in NO synthesis, including nitric oxide synthase-like genes (NOL2 and NOL3) and nitrate (NIA1) and nitrite reductase (NII1), generating single and double ?nia1?nii1, ?nia1?nol3, and ?nol2?nol3 mutants. We demonstrate that Magnaporthe oryzae generates NO during germination and in early development. Removal of NO delays germling development and reduces disease lesion numbers. NO is not generated by the candidate proteins tested, nor by other arginine-dependent NO systems, by polyamine oxidase activity or non-enzymatically by low pH. Furthermore, we show that, while NIA1 and NII1 are essential for nitrate assimilation, NIA1, NII1, NOL2 and NOL3 are all dispensable for pathogenicity. Development of M. oryzae and initiation of infection are critically dependent on fungal NO synthesis, but its mode of generation remains obscure. PMID:23072575

Samalova, Marketa; Johnson, Jasper; Illes, Mary; Kelly, Steven; Fricker, Mark; Gurr, Sarah

2012-10-16

57

Characterization of Rice Black-Streaked Dwarf Virus- and Rice Stripe Virus-Derived siRNAs in Singly and Doubly Infected Insect Vector Laodelphax striatellus  

PubMed Central

Replication of RNA viruses in insect cells triggers an antiviral defense that is mediated by RNA interference (RNAi) which generates viral-derived small interfering RNAs (siRNAs). However, it is not known whether an antiviral RNAi response is also induced in insects by reoviruses, whose double-stranded RNA genome replication is thought to occur within core particles. Deep sequencing of small RNAs showed that when the small brown planthopper (Laodelphax striatellus) was infected by Rice black-streaked dwarf virus (RBSDV) (Reoviridae; Fijivirus), more viral-derived siRNAs accumulated than when the vector insect was infected by Rice stripe virus (RSV), a negative single-stranded RNA virus. RBSDV siRNAs were predominantly 21 and 22 nucleotides long and there were almost equal numbers of positive and negative sense. RBSDV siRNAs were frequently generated from hotspots in the 5?- and 3?-terminal regions of viral genome segments but these hotspots were not associated with any predicted RNA secondary structures. Under laboratory condition, L. striatellus can be infected simultaneously with RBSDV and RSV. Double infection enhanced the accumulation of particular genome segments but not viral coat protein of RBSDV and correlated with an increase in the abundance of siRNAs derived from RBSDV. The results of this study suggest that reovirus replication in its insect vector potentially induces an RNAi-mediated antiviral response.

Shen, Jiangfeng; Lv, Yuanda; Ji, Yongqiang; Sun, Liying; Chen, Jianping

2013-01-01

58

The effect of 'Candidatus Liberibacter asiaticus' infection on the proteomic profiles and nutritional status of pre-symptomatic and symptomatic grapefruit (Citrus paradisi) plants.  

PubMed

BACKGROUND: Huanglongbing (HLB) is a highly destructive citrus disease which threatens citrus production worldwide and 'Candidatus Liberibacter asiaticus' (Las), a non-culturable phloem-limited bacterium, is an associated causal agent of the disease. To better understand the physiological and molecular processes involved in host responses to Las, 2-DE and mass spectrometry analyses, as well as ICP spectroscopy analysis were employed to elucidate the global protein expression profiles and nutrient concentrations in leaves of Las-infected grapefruit plants at pre-symptomatic or symptomatic stages for HLB. RESULTS: This study identified 123 protein spots out of 191 spots that showed significant changes in the leaves of grapefruit plants in response to Las infection and all identified spots matched to 69 unique proteins/peptides. A down-regulation of 56 proteins including those associated with photosynthesis, protein synthesis, and metabolism was correlated with significant reductions in the concentrations of Ca, Mg, Fe, Zn, Mn, and Cu in leaves of grapefruit plants in response to Las infection, particularly in symptomatic plants. Oxygen-evolving enhancer (OEE) proteins, a PSI 9 kDa protein, and a Btf3-like protein were among a small group of proteins that were down-regulated in both pre-symptomatic and symptomatic plants in response to Las infection. Furthermore, a Las-mediated up-regulation of 13 grapefruit proteins was detected, which included Cu/Zn superoxide dismutase, chitinases, lectin-related proteins, miraculin-like proteins, peroxiredoxins and a CAP 160 protein. Interestingly, a Las-mediated up-regulation of granule-bound starch synthase was correlated with an increase in the K concentrations of pre-symptomatic and symptomatic plants. CONCLUSIONS: This study constitutes the first attempt to characterize the interrelationships between protein expression and nutritional status of Las-infected pre-symptomatic or symptomatic grapefruit plants and sheds light on the physiological and molecular mechanisms associated with HLB disease development. PMID:23578104

Nwugo, Chika C; Lin, Hong; Duan, Yongping; Civerolo, Edwin L

2013-04-11

59

The effect of 'Candidatus Liberibacter asiaticus' infection on the proteomic profiles and nutritional status of pre-symptomatic and symptomatic grapefruit (Citrus paradisi) plants  

PubMed Central

Background Huanglongbing (HLB) is a highly destructive citrus disease which threatens citrus production worldwide and ‘Candidatus Liberibacter asiaticus’ (Las), a non-culturable phloem-limited bacterium, is an associated causal agent of the disease. To better understand the physiological and molecular processes involved in host responses to Las, 2-DE and mass spectrometry analyses, as well as ICP spectroscopy analysis were employed to elucidate the global protein expression profiles and nutrient concentrations in leaves of Las-infected grapefruit plants at pre-symptomatic or symptomatic stages for HLB. Results This study identified 123 protein spots out of 191 spots that showed significant changes in the leaves of grapefruit plants in response to Las infection and all identified spots matched to 69 unique proteins/peptides. A down-regulation of 56 proteins including those associated with photosynthesis, protein synthesis, and metabolism was correlated with significant reductions in the concentrations of Ca, Mg, Fe, Zn, Mn, and Cu in leaves of grapefruit plants in response to Las infection, particularly in symptomatic plants. Oxygen-evolving enhancer (OEE) proteins, a PSI 9 kDa protein, and a Btf3-like protein were among a small group of proteins that were down-regulated in both pre-symptomatic and symptomatic plants in response to Las infection. Furthermore, a Las-mediated up-regulation of 13 grapefruit proteins was detected, which included Cu/Zn superoxide dismutase, chitinases, lectin-related proteins, miraculin-like proteins, peroxiredoxins and a CAP 160 protein. Interestingly, a Las-mediated up-regulation of granule-bound starch synthase was correlated with an increase in the K concentrations of pre-symptomatic and symptomatic plants. Conclusions This study constitutes the first attempt to characterize the interrelationships between protein expression and nutritional status of Las-infected pre-symptomatic or symptomatic grapefruit plants and sheds light on the physiological and molecular mechanisms associated with HLB disease development.

2013-01-01

60

Analysis of the Structure of the AVR1-CO39 Avirulence Locus in Virulent Rice-Infecting Isolates of Magnaporthe grisea  

Technology Transfer Automated Retrieval System (TEKTRAN)

The AVR1-CO39 gene that came from a Magnaporthe grisea isolate from weeping lovegrass controls avirulence on the rice cultivar CO39. AVR1-CO39 was not present in the genome of the rice-infecting M. grisea isolate Guy11 from French Guyana, suggesting that the gene had been deleted. Molecular analysis...

61

Characterization of the microbial community structure in Candidatus Liberibacter asiaticus-infected citrus plants treated with antibiotics in the field  

PubMed Central

Background Huanglongbing (HLB) is a worldwide devastating disease of citrus. There are no effective control measures for this newly emerging but century-old disease. Previously, we reported a combination of Penicillin G and Streptomycin was effective in eliminating or suppressing the associated bacterium, ‘Candidatus Liberibacter asiaticus’ (Las). Results Here we report the bacterial composition and community structure in HLB-affected citrus plants during a growing season and while being treated with antibiotic combinations PS (Penicillin G and Streptomycin) and KO (Kasugamycin and Oxytetracycline) using the Phylochip™ G3 array. Both antibiotic treatments resulted in significantly lower Las bacterial titers (Pr<0.05) and hybridization scores. Of the 50,000+ available operational taxonomic units (OTUs) on PhyloChip™ G3, 7,028 known OTUs were present in citrus leaf midribs. These OTUs were from 58 phyla, of which five contained 100 or more OTUs, Proteobacteria (44.1%), Firmicutes (23.5%), Actinobacteria (12.4%), Bacteroidetes (6.6%) and Cyanobacteria (3.2%). In the antibiotic treated samples, the number of OTUs decreased to a total of 5,599. The over-all bacterial diversity decreased with the antibiotic treatments, as did the abundance of 11 OTUs within Proteobacteria, Firmicutes, Bacteroidetes and Planctomycetes. Within the Proteobacteria, ten OTUs representing the class ?-proteobacteria increased in abundance after four months of treatment, when the Las bacterium was at its lowest level in the HLB-affected citrus field plants. Conclusions Our data revealed that Proteobacteria was constantly the dominant bacterial phylum recovered from citrus leaf midribs, with the ?-proteobacterial and the ?-proteobacterial classes vying for prevalence. In addition, the level of bacterial diversity found in the leaf midribs of field citrus was greater than previously described. Bacterial cells in close proximity may be able to modify their microenvironment, making the composition of the microbial community an important factor in the ability of Las to cause HLB progression. A low Las level was seen as an annual fluctuation, part of the bacterial population dynamics, and as a response to the antibiotic treatments.

2013-01-01

62

The decline in quantity of bacteria of Xanthomonas axonopodis pv citri dispersed from canker-infected citrus plants during wind/rain events  

Technology Transfer Automated Retrieval System (TEKTRAN)

Background and objectives. Citrus canker (caused by Xanthomonas axonopodis pv. citri, Xac) is an important disease of citrus in several tropical and sub-tropical citrus growing regions. Canker damaged trees produce less yield and the blemished fruit is unfit for fresh sale, so processing becomes the...

63

Screening molecules for control of citrus Huanglongbing (HLB) using an optimized regeneration system for 'Candidatus Liberibacter asiaticus' infected periwinkle (Catharunthus roseus) cuttings  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus huanglongbing (HLB) ( also known as citrus greening) is one of the most destructive diseases of citrus worldwide. The disease is associated with three different species of Candidatus Liberibacter, of which, ‘Ca. L. asiaticus’ (Las) is the most widely-distributed. An improved system using HLB-...

64

Citrus aurantium  

Microsoft Academic Search

\\u000a Citrus aurantium has enjoyed a rich history of uses in food, cosmetics, and medicine Recent misuse of this product for weight loss, however,\\u000a is threatening to tarnish the holistic reputation of this fruit Manufacturers are isolating and concentrating the synephnne\\u000a content from the 0 33 mg\\/g contained in the pulp of whole fruit to 20 mg\\/g in some dietary supplements,

Anders Westanmo

65

Evaluation of Protocol for Assessing the Reaction of Rice and Wheat Germplasm to Infection by Meloidogyne graminicola  

PubMed Central

Root-knot nematode (Meloidogyne graminicola), an important and widespread pathogen, causes high yield losses in rice with limited information on wheat and on efficient management. Absence of uniform screening protocols is contributing to slow progress of host resistance development. To develop an efficient screening protocol, several greenhouse studies were conducted, and effects of incubation period, inoculum level, inoculation method, seedling age, and their interactions on root-galling severity (RGS) ratings and reproductive factor (RF) values of M. graminicola were determined. At 2 eggs/cm3 soil, significantly lower RGS but higher RF values were observed at 60 days than at 45 days of incubation. Meloidogyne graminicola reproduced six times more on rice than on wheat where the RGS index in both crops increased steadily with increasing inoculum levels, but RF increased at lower levels and decreased beyond a maximum at medium inoculum levels. Inoculum level, container size, seedling age, inoculation method, and their interactions impacted nematode infection and reproduction. The protocol was verified on eleven rice germplasm lines and seven wheat cultivars using the resistance index (RI) calculated from RGS and RF, to screen rice and wheat germplasm.

Pokharel, Ramesh R.; Duxbury, John M.; Abawai, George

2012-01-01

66

Transcriptome profiling of the rice blast fungus during invasive plant infection and in vitro stresses  

Microsoft Academic Search

BACKGROUND: Rice blast is the most threatening disease to cultivated rice. Magnaporthe oryzae, its causal agent, is likely to encounter environmental challenges during invasive growth in its host plants that require shifts in gene expression to establish a compatible interaction. Here, we tested the hypothesis that gene expression patterns during in planta invasive growth are similar to in vitro stress

Sandra M Mathioni; André Beló; Christopher J Rizzo; Ralph A Dean; Nicole M Donofrio

2011-01-01

67

Bacterial diversity analysis of Huanglongbing pathogen-infected citrus, using PhyloChip and 16S rRNA gene clone library sequencing  

Microsoft Academic Search

The bacterial diversity associated with citrus leaf midribs was characterized 1 from citrus groves that contained the Huanglongbing (HLB) pathogen, which has yet to be cultivated in vitro. We employed a combination of high-density phylogenetic 16S rDNA microarray and 16S rDNA clone library sequencing to determine the microbial community composition of symptomatic and asymptomatic citrus midribs. Our results revealed that

Uma Shankar Sagaram; Kristen M. DeAngelis; Pankaj Trivedi; Gary L. Andersen; Shi-En Lu; Nian Wang

2009-01-01

68

Transcriptome Profiling of Citrus Fruit Response to Huanglongbing Disease  

Microsoft Academic Search

Huanglongbing (HLB) or “citrus greening” is the most destructive citrus disease worldwide. In this work, we studied host responses of citrus to infection with Candidatus Liberibacter asiaticus (CaLas) using next-generation sequencing technologies. A deep mRNA profile was obtained from peel of healthy and HLB-affected fruit. It was followed by pathway and protein-protein network analysis and quantitative real time PCR analysis

Federico Martinelli; Sandra L. Uratsu; Ute Albrecht; Russell L. Reagan; My L. Phu; Monica Britton; Vincent Buffalo; Joseph Fass; Elizabeth Leicht; Weixiang Zhao; Dawei Lin; Raissa DSouza; Cristina E. Davis; Kim D. Bowman; Abhaya M. Dandekar

2012-01-01

69

Morphology, Ultrastructure, and Bacteriophage Infection of the Helical Mycoplasma-Like Organism (Spiroplasma citri gen. nov., sp. nov.) Cultured from "Stubborn" Disease of Citrus  

PubMed Central

The mycoplasma-like organism Spiroplasma citri gen. nov., sp. nov., isolated from citrus infected with “Stubborn” disease and carried in serial cultures in several media, was examined by dark-field microscopy and electron microscopy of negatively-stained and shadowed preparations and of sections. It grows as motile, helical filaments in liquid, but as nonmotile, nonhelical filaments and round bodies in agar cultures. Helicity and motility are lost in old broth cultures and upon addition of a variety of negative stains, fixatives, and other solutions. No organelles accounting for motility are present, but a layer of surface projections is present on the surface of the single, bounding membrane. The mycoplasma produces a tailed, type B bacteriophage which appear to attach to the outer layer. Helical filaments are preserved in ammonium molybdate, but not in sodium phosphotungstate, and by fixation in Formalin or glutaraldehyde made up in medium, but not by osmium nor by glutaraldehyde in cacodylate buffer. This mycoplasma appears similar to the noncultured helical microorganism in corn stunt-diseased tissues and is probably a representative of a new group of mycoplasmas which are in possession of surface projections, rotary motility, and bacteriophage infection. Images

Cole, Roger M.; Tully, Joseph G.; Popkin, Terry J.; Bove, Joseph M.

1973-01-01

70

Carotenoid inhibitors reduce strigolactone production and Striga hermonthica infection in rice.  

PubMed

The strigolactones are internal and rhizosphere signalling molecules in plants that are biosynthesised through carotenoid cleavage. They are secreted by host roots into the rhizosphere where they signal host-presence to the symbiotic arbuscular mycrorrhizal (AM) fungi and the parasitic plants of the Orobanche, Phelipanche and Striga genera. The seeds of these parasitic plants germinate after perceiving these signalling molecules. After attachment to the host root, the parasite negatively affects the host plant by withdrawing water, nutrients and assimilates through a direct connection with the host xylem. In many areas of the world these parasites are a threat to agriculture but so far very limited success has been achieved to minimize losses due to these parasitic weeds. Considering the carotenoid origin of the strigolactones, in the present study we investigated the possibilities to reduce strigolactone production in the roots of plants by blocking carotenoid biosynthesis using carotenoid inhibitors. Hereto the carotenoid inhibitors fluridone, norflurazon, clomazone and amitrole were applied to rice either through irrigation or through foliar spray. Irrigation application of all carotenoid inhibitors and spray application of amitrole significantly decreased strigolactone production, Striga hermonthica germination and Striga infection, also in concentrations too low to affect growth and development of the host plant. Hence, we demonstrate that the application of carotenoid inhibitors to plants can affect S. hermonthica germination and attachment indirectly by reducing the strigolactone concentration in the rhizosphere. This finding is useful for further studies on the relevance of the strigolactones in rhizosphere signalling. Since these inhibitors are available and accessible, they may represent an efficient technology for farmers, including poor subsistence farmers in the African continent, to control these harmful parasitic weeds. PMID:20732294

Jamil, Muhammad; Charnikhova, Tatsiana; Verstappen, Francel; Bouwmeester, Harro

2010-08-21

71

Expression of defense-related genes in response to mechanical wounding and Phytophthora parasitica infection in Poncirus trifoliata and Citrus sunki  

Microsoft Academic Search

Phytophthora parasitica have caused severe damage in Citrus nurseries and orchards worldwide. The purpose of these experiments was to determine how plant defense pathways are induced by P. parasitica and if induction differs in susceptible (Citrus sunki) and resistant (Poncirus trifoliata) interactions. Furthermore, to test the effect of simple wounding on the induction of defense-related genes, plants were mechanically wounded and

Leonardo P. Boava; Mariângela Cristofani-Yaly; Rodrigo M. Stuart; Marcos A. Machado

2011-01-01

72

Increased tryptophan decarboxylase and monoamine oxidase activities induce Sekiguchi lesion formation in rice infected with Magnaporthe grisea.  

PubMed

Sekiguchi lesion (sl)-mutant rice infected with Magnaporthe grisea showed increased light-dependent tryptophan decarboxylase (TDC) and monoamine oxidase (MAO) activities. TDC and MAO activities were observed before the penetration of M. grisea to rice cells and maintained high levels even after Sekiguchi lesion formation. Light-dependent expression of TDC gene was observed in leaves inoculated with M. grisea before Sekiguchi lesion formation. Spore germination fluid (SGF) of M. grisea also induced Sekiguchi lesion formation accompanied by increased enzymes activities and tryptamine accumulation. Sekiguchi lesion was also induced by treatments with tryptamine and beta-phenylethylamine, which are substrates for MAO, but was not induced by non-substrates such as indole-3-propionic acid, (+/-)-phenylethylamine and tryptophan under light. Light-dependent induction of Sekiguchi lesion by tryptamine was significantly inhibited in the presence of MAO inhibitors, metalaxyl and semicarbazide, and H2O2-scavengers, ascorbic acid and catalase. H2O2 in M. grisea-infected leaves with and without Sekiguchi lesions was demonstrated directly in situ by strong 3,3'-diaminobenzidine (DAB) staining. On the other hand, H2O2 induced Sekiguchi lesions on leaves of cv. Sekiguchi-asahi under light, but not in darkness. This difference was associated with the decrease of catalase activity in infected leaves under light and the absence of decrease in darkness. We hypothesize that the H2O2-induced breakdown of cellular organelles such as chloroplasts and mitochondria in mesophyll cells may cause high TDC and MAO activities and the development of Sekiguchi lesion, and that the sl gene products in wild-type rice may function as a suppressor of organelle breakdown caused by chemical or environmental stress. PMID:14535886

Ueno, Makoto; Shibata, Hitoshi; Kihara, Junichi; Honda, Yuichi; Arase, Sakae

2003-10-01

73

Dramatic Change in Citrus tristeza virus populations in the Dominican Republic  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus tristeza virus (CTV) is the most destructive viral pathogen of citrus and has been an important concern for the citrus industry in the Dominican Republic. Earlier studies documented widespread distribution of mild isolates of the T30 genotype, which caused no disease in the infected trees, an...

74

DISTANCE OF SPREAD OF ASIAN CITRUS CANKER FROM SOURCE OF INFECTION IN COMMERCIAL PLANTINGS IN SAO PAULO, BRAZIL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Xanthomonas axonopodis pv. citri (Xac)-infected trees continued to occur in São Paulo commercial plantings previously subjected to eradication, indicating that removing all trees within a 30-m radius of known Xac-infected trees was insufficient to eradicate the disease within infected orchards. Pos...

75

Diversity of endophytic bacterial populations and their interaction with Xylella fastidiosa in citrus plants  

Microsoft Academic Search

Citrus variegated chlorosis (CVC) is caused by Xylella fastidiosa, a phytopathogenic bacterium that can infect all Citrus sinensis cultivars. The endophytic bacterial communities of healthy, resistant, and CVC-affected citrus plants were studied by using cultivation as well as cultivation-independent techniques. The endophytic communities were assessed in surface-disinfected citrus branches by plating and denaturing gradient gel electrophoresis (DGGE). Dominant isolates were

Welington L. Araujo; Joelma Marcon; Walter Maccheroni; Elsas van J. D; Vuurde van J. W. L; Azevedo de J. L

2002-01-01

76

Towards Defining Nutrient Conditions Encountered by the Rice Blast Fungus during Host Infection  

PubMed Central

Fungal diseases cause enormous crop losses, but defining the nutrient conditions encountered by the pathogen remains elusive. Here, we generated a mutant strain of the devastating rice pathogen Magnaporthe oryzae impaired for de novo methionine biosynthesis. The resulting methionine-requiring strain grew strongly on synthetic minimal media supplemented with methionine, aspartate or complex mixtures of partially digested proteins, but could not establish disease in rice leaves. Live-cell-imaging showed the mutant could produce normal appressoria and enter host cells but failed to develop, indicating the availability or accessibility of aspartate and methionine is limited in the plant. This is the first report to demonstrate the utility of combining biochemical genetics, plate growth tests and live-cell-imaging to indicate what nutrients might not be readily available to the fungal pathogen in rice host cells.

Wilson, Richard A.; Fernandez, Jessie; Quispe, Cristian F.; Gradnigo, Julien; Seng, Anya; Moriyama, Etsuko; Wright, Janet D.

2012-01-01

77

Genetic Transformation in Citrus  

PubMed Central

Citrus is one of the world's important fruit crops. Recently, citrus molecular genetics and biotechnology work have been accelerated in the world. Genetic transformation, a biotechnological tool, allows the release of improved cultivars with desirable characteristics in a shorter period of time and therefore may be useful in citrus breeding programs. Citrus transformation has now been achieved in a number of laboratories by various methods. Agrobacterium tumefaciens is used mainly in citrus transformation studies. Particle bombardment, electroporation, A. rhizogenes, and a new method called RNA interference are used in citrus transformation studies in addition to A. tumefaciens. In this review, we illustrate how different gene transformation methods can be employed in different citrus species.

Donmez, Dicle; Simsek, Ozhan; Izgu, Tolga; Aka Kacar, Yildiz; Yalcin Mendi, Yesim

2013-01-01

78

Clues into the metagenome of huanglongbing infected citrus by analysis of ancillary sequences from Ion Torrent whole genome Candidatus Liberibacter asiaticus sequencing  

Technology Transfer Automated Retrieval System (TEKTRAN)

Huanglongbing (HLB) is a globally devastating disease of citrus. Presently, three etiological agents are associated with HLB and include; Candidatus Liberibacter asiaticus (CLas), Candidatus Liberibacter americanus; and Candidatus Liberibacter africanus. Attempts to determine alternate (non-Liberi...

79

Improved frequency of transformation in rice and maize by treatment of immature embryos with centrifugation and heat prior to infection with Agrobacterium tumefaciens  

Microsoft Academic Search

The efficiency of transformation was improved by treating immature embryos with heat and centrifugation before infection with Agrobacterium tumefaciens in rice and maize. Because the effects were detected both in the levels of transgene expression after co-cultivation and in the number of independent transgenic plants obtained per embryo, conditions were first optimized based on the transgene expression, and then transformants

Yukoh Hiei; Yuji Ishida; Keisuke Kasaoka; Toshihiko Komari

2006-01-01

80

High activities and mRNA expression of pyrophosphate-fructose-6-phosphate-phosphotransferase and 6-phosphofructokinase are induced as a response to Rhizoctonia solani infection in rice leaf sheaths  

Microsoft Academic Search

Rice sheath blight disease caused by Rhizoctonia solani Kuhn results in significant yield and quality losses in rice growing areas worldwide. The glycolytic pathway is important in the resistance response to R. solani infection in rice. This study examined one of the regulatory steps in this pathway catalyzed by pyrophosphate- fructose-6-phosphate-phosphotransferase (PFP) and 6-phosphofructokinase (PFK). PFP and PFK activity in

J. M. Mutuku; A. Nose

81

The MET13 Methylenetetrahydrofolate Reductase Gene Is Essential for Infection-Related Morphogenesis in the Rice Blast Fungus Magnaporthe oryzae  

PubMed Central

Methylenetetrahydrofolate reductases (MTHFRs) play a key role in the biosynthesis of methionine in both prokaryotic and eukaryotic organisms. In this study, we report the identification of a novel T-DNA-tagged mutant WH672 in the rice blast fungus Magnaporthe oryzae, which was defective in vegetative growth, conidiation and pathogenicity. Analysis of the mutation confirmed a single T-DNA insertion upstream of MET13, which encodes a 626-amino-acid protein encoding a MTHFR. Targeted gene deletion of MET13 resulted in mutants that were non-pathogenic and significantly impaired in aerial growth and melanin pigmentation. All phenotypes associated with ?met13 mutants could be overcome by addition of exogenous methionine. The M. oryzae genome contains a second predicted MTHFR-encoding gene, MET12. The deduced amino acid sequences of Met13 and Met12 share 32% identity. Interestingly, ?met12 mutants produced significantly less conidia compared with the isogenic wild-type strain and grew very poorly in the absence of methionine, but were fully pathogenic. Deletion of both genes resulted in ?met13?met12 mutants that showed similar phenotypes to single ?met13 mutants. Taken together, we conclude that the MTHFR gene, MET13, is essential for infection-related morphogenesis by the rice blast fungus M. oryzae.

Wang, Hong; Wang, Congcong; Li, Ya; Yue, Xiaofeng; Ma, Zhonghua; Talbot, Nicholas J.; Wang, Zhengyi

2013-01-01

82

The MET13 Methylenetetrahydrofolate Reductase Gene Is Essential for Infection-Related Morphogenesis in the Rice Blast Fungus Magnaporthe oryzae.  

PubMed

Methylenetetrahydrofolate reductases (MTHFRs) play a key role in the biosynthesis of methionine in both prokaryotic and eukaryotic organisms. In this study, we report the identification of a novel T-DNA-tagged mutant WH672 in the rice blast fungus Magnaporthe oryzae, which was defective in vegetative growth, conidiation and pathogenicity. Analysis of the mutation confirmed a single T-DNA insertion upstream of MET13, which encodes a 626-amino-acid protein encoding a MTHFR. Targeted gene deletion of MET13 resulted in mutants that were non-pathogenic and significantly impaired in aerial growth and melanin pigmentation. All phenotypes associated with ?met13 mutants could be overcome by addition of exogenous methionine. The M. oryzae genome contains a second predicted MTHFR-encoding gene, MET12. The deduced amino acid sequences of Met13 and Met12 share 32% identity. Interestingly, ?met12 mutants produced significantly less conidia compared with the isogenic wild-type strain and grew very poorly in the absence of methionine, but were fully pathogenic. Deletion of both genes resulted in ?met13?met12 mutants that showed similar phenotypes to single ?met13 mutants. Taken together, we conclude that the MTHFR gene, MET13, is essential for infection-related morphogenesis by the rice blast fungus M. oryzae. PMID:24116181

Yan, Xia; Que, Yawei; Wang, Hong; Wang, Congcong; Li, Ya; Yue, Xiaofeng; Ma, Zhonghua; Talbot, Nicholas J; Wang, Zhengyi

2013-10-07

83

Silicon enhances photochemical efficiency and adjusts mineral nutrient absorption in Magnaporthe oryzae infected rice plants  

Microsoft Academic Search

Silicon (Si) has been verified to play an important role in enhancing plant resistance against pathogens, but the exact mechanisms\\u000a remain unclear. Two near-isogenic lines of rice (Oryza sativa L.), CO39 (blast susceptible), and C101LAC (Pi-1) (blast resistant), were hydroponically grown to study the effects of exogenous silicon application on the changes of disease\\u000a incidence, mineral nutrient concentrations, chlorophyll content,

Dan Gao; Kunzheng Cai; Jining Chen; Shiming Luo; Rensen Zeng; Jianyuan Yang; Xiaoyuan Zhu

2011-01-01

84

Transcriptome profiling of the rice blast fungus during invasive plant infection and in vitro stresses  

PubMed Central

Background Rice blast is the most threatening disease to cultivated rice. Magnaporthe oryzae, its causal agent, is likely to encounter environmental challenges during invasive growth in its host plants that require shifts in gene expression to establish a compatible interaction. Here, we tested the hypothesis that gene expression patterns during in planta invasive growth are similar to in vitro stress conditions, such as nutrient limitation, temperature up shift and oxidative stress, and determined which condition most closely mimicked that of in planta invasive growth. Gene expression data were collected from these in vitro experiments and compared to fungal gene expression during the invasive growth phase at 72 hours post-inoculation in compatible interactions on two grass hosts, rice and barley. Results We identified 4,973 genes that were differentially expressed in at least one of the in planta and in vitro stress conditions when compared to fungal mycelia grown in complete medium, which was used as reference. From those genes, 1,909 showed similar expression patterns between at least one of the in vitro stresses and rice and/or barley. Hierarchical clustering of these 1,909 genes showed three major clusters in which in planta conditions closely grouped with the nutrient starvation conditions. Out of these 1,909 genes, 55 genes and 129 genes were induced and repressed in all treatments, respectively. Functional categorization of the 55 induced genes revealed that most were either related to carbon metabolism, membrane proteins, or were involved in oxidoreduction reactions. The 129 repressed genes showed putative roles in vesicle trafficking, signal transduction, nitrogen metabolism, or molecular transport. Conclusions These findings suggest that M. oryzae is likely primarily coping with nutrient-limited environments at the invasive growth stage 72 hours post-inoculation, and not with oxidative or temperature stresses.

2011-01-01

85

Nature of resistance in rice ( Oryza sativa L) to the root-knot nematode ( Meloidogyne graminicola Golden and Birchfield) II. Histopathology of nematode infection in rice varieties  

Microsoft Academic Search

Disruption and hypertrophy of cortical cells due to the migration and movement of larvae ofMeloidogyne graminicola partly contributed to the development of knots in rice roots. Hyperplasia of protophloem and abnormal xylem proliferation\\u000a caused swelling of stele at sites of nematode attack and establishment. In tolerant rice varieties, poor giant cell formation\\u000a caused delay in nematode development and in the

Rabindra Narayan Jena; Y Seshagiri Rao

1977-01-01

86

Gene expression in Citrus sinensis fruit tissues harvested from huanglongbing-infected trees: comparison with girdled fruit.  

PubMed

Distribution of viable Candidatus Liberibacter asiaticus (CaLas) in sweet orange fruit and leaves ('Hamlin' and 'Valencia') and transcriptomic changes associated with huanglongbing (HLB) infection in fruit tissues are reported. Viable CaLas was present in most fruit tissues tested in HLB trees, with the highest titre detected in vascular tissue near the calyx abscission zone. Transcriptomic changes associated with HLB infection were analysed in flavedo (FF), vascular tissue (VT), and juice vesicles (JV) from symptomatic (SY), asymptomatic (AS), and healthy (H) fruit. In SY 'Hamlin', HLB altered the expression of more genes in FF and VT than in JV, whereas in SY 'Valencia', the number of genes whose expression was changed by HLB was similar in these tissues. The expression of more genes was altered in SY 'Valencia' JV than in SY 'Hamlin' JV. More genes were also affected in AS 'Valencia' FF and VT than in AS 'Valencia' JV. Most genes whose expression was changed by HLB were classified as transporters or involved in carbohydrate metabolism. Physiological characteristics of HLB-infected and girdled fruit were compared to differentiate between HLB-specific and carbohydrate metabolism-related symptoms. SY and girdled fruit were smaller than H and ungirdled fruit, respectively, with poor juice quality. However, girdling did not cause misshapen fruit or differential peel coloration. Quantitative PCR analysis indicated that many selected genes changed their expression significantly in SY flavedo but not in girdled flavedo. Mechanisms regulating development of HLB symptoms may lie in the host disease response rather than being a direct consequence of carbohydrate starvation. PMID:22407645

Liao, Hui-Ling; Burns, Jacqueline K

2012-03-09

87

Gene expression in Citrus sinensis fruit tissues harvested from huanglongbing-infected trees: comparison with girdled fruit  

PubMed Central

Distribution of viable Candidatus Liberibacter asiaticus (CaLas) in sweet orange fruit and leaves (‘Hamlin’ and ‘Valencia’) and transcriptomic changes associated with huanglongbing (HLB) infection in fruit tissues are reported. Viable CaLas was present in most fruit tissues tested in HLB trees, with the highest titre detected in vascular tissue near the calyx abscission zone. Transcriptomic changes associated with HLB infection were analysed in flavedo (FF), vascular tissue (VT), and juice vesicles (JV) from symptomatic (SY), asymptomatic (AS), and healthy (H) fruit. In SY ‘Hamlin’, HLB altered the expression of more genes in FF and VT than in JV, whereas in SY ‘Valencia’, the number of genes whose expression was changed by HLB was similar in these tissues. The expression of more genes was altered in SY ‘Valencia’ JV than in SY ‘Hamlin’ JV. More genes were also affected in AS ‘Valencia’ FF and VT than in AS ‘Valencia’ JV. Most genes whose expression was changed by HLB were classified as transporters or involved in carbohydrate metabolism. Physiological characteristics of HLB-infected and girdled fruit were compared to differentiate between HLB-specific and carbohydrate metabolism-related symptoms. SY and girdled fruit were smaller than H and ungirdled fruit, respectively, with poor juice quality. However, girdling did not cause misshapen fruit or differential peel coloration. Quantitative PCR analysis indicated that many selected genes changed their expression significantly in SY flavedo but not in girdled flavedo. Mechanisms regulating development of HLB symptoms may lie in the host disease response rather than being a direct consequence of carbohydrate starvation.

Liao, Hui-Ling; Burns, Jacqueline K.

2012-01-01

88

An Inexpensive and Safe Experiment to Demonstrate Koch's Postulates Using Citrus Fruit  

ERIC Educational Resources Information Center

|Citrus fruit (oranges, tangerines, grapefruit or lemons) purchased in a grocery store can be experimentally infected with readily-available sources of "Penicillium digitatum" to demonstrate the four basic steps of Koch's postulates, also known as proof of pathogenicity. The mould is isolated from naturally-infected citrus fruit into pure culture…

Jakobi, Steven

2010-01-01

89

Phaeoramularia fruit and leaf spot of citrus with special reference to Kenya  

Microsoft Academic Search

Fruit and leaf spot of citrus caused by Phaeoramularia angolensis was first observed in Angola and Mozambique in 1952. The disease has now spread to 15 countries, south of Sahara, and recently to Yemen, in the Arabian Peninsula. All citrus species are affected with grapefruit, with orange being the most susceptible. P. angolensis infects foliage, fruit and stems. Severe infection

A. A. Seif; R. J. Hillocks

1993-01-01

90

Wind speed effects on the quantity of Xanthomonas citri subsp. citri dispersed downwind from canopies of grapefruit trees infected with citrus canker  

Technology Transfer Automated Retrieval System (TEKTRAN)

The epidemic of citrus canker (Xanthomonas citri subsp. citri, Xcc) in Florida continues to expand since termination of the eradication program in 2006. Storms are known to be associated with disease spread, but little information exists on the interaction of fundamental physical and biological proc...

91

SPATIAL PATTERN ANALYSIS OF CITRUS CANKER INFECTED PLANTINGS IN SÃO PAULO BRAZIL AND IMPLICATION OF THE ASIAN LEAFMINER ON THE POTENTIAL DISPERSAL PROCESSES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Eradication of Asiatic Citrus Canker (ACC) has become increasingly difficult over the last decade following the introduction of the Asian leafminer into Brazil and Florida, which lead to changes in the eradication protocols. The present study, undertaken in Brazil, was aimed at characterizing the s...

92

Common Genetic Pathways Regulate Organ-Specific Infection-Related Development in the Rice Blast Fungus[W  

PubMed Central

Magnaporthe oryzae is the most important fungal pathogen of rice (Oryza sativa). Under laboratory conditions, it is able to colonize both aerial and underground plant organs using different mechanisms. Here, we characterize an infection-related development in M. oryzae produced on hydrophilic polystyrene (PHIL-PS) and on roots. We show that fungal spores develop preinvasive hyphae (pre-IH) from hyphopodia (root penetration structures) or germ tubes and that pre-IH also enter root cells. Changes in fungal cell wall structure accompanying pre-IH are seen on both artificial and root surfaces. Using characterized mutants, we show that the PMK1 (for pathogenicity mitogen-activated protein kinase 1) pathway is required for pre-IH development. Twenty mutants with altered pre-IH differentiation on PHIL-PS identified from an insertional library of 2885 M. oryzae T-DNA transformants were found to be defective in pathogenicity. The phenotypic analysis of these mutants revealed that appressorium, hyphopodium, and pre-IH formation are genetically linked fungal developmental processes. We further characterized one of these mutants, M1373, which lacked the M. oryzae ortholog of exportin-5/Msn5p (EXP5). Mutants lacking EXP5 were much less virulent on roots, suggesting an important involvement of proteins and/or RNAs transported by EXP5 during M. oryzae root infection.

Tucker, Sara L.; Besi, Maria I.; Galhano, Rita; Franceschetti, Marina; Goetz, Stephan; Lenhert, Steven; Osbourn, Anne; Sesma, Ane

2010-01-01

93

Development of real-time PCR systems based on SYBR ® Green I and TaqMan ® technologies for specific quantitative detection of Phoma tracheiphila in infected Citrus  

Microsoft Academic Search

Real-time PCR assays based on SYBR® Green I and TaqMan® technologies were developed for in planta detection and quantification of Phoma tracheiphila, the mitosporic fungus causing ‘mal secco’ disease on citrus. Primers and a hybridization probe were designed on the basis\\u000a of the internal transcribed spacer (ITS) region of the nuclear rRNA genes. The real-time PCR assays were compared with

Maria Antonietta Demontis; Santa Olga Cacciola; Marcella Orrù; Virgilio Balmas; Valentina Chessa; Bianca Elena Maserti; Laura Mascia; Francesco Raudino; Gaetano Magnano di San Lio; Quirico Migheli

2008-01-01

94

Micropropagation of Citrus  

Microsoft Academic Search

\\u000a The genus Citrus is cultured in more than 100 countries making it one of the most important commercial fruit crops in terms\\u000a of economic value and human nutrition (Barlass and Skene, 1986). Fresh fruits and juice are the most significant citrus products,\\u000a but essential oils, pectin, and marmalade, as well as candied and dried rinds, also have commercial value (Barlass

Francesco Carimi; Fabio De Pasquale

95

Screening USDA Citrus Germplasm for Resistance to Citrus Canker  

Technology Transfer Automated Retrieval System (TEKTRAN)

Asiatic citrus canker (Acc) (causal organism Xanthomonas citri subspc. citri (Xcc) is threatening sustainability of the Florida citrus industry. Resistant cultivars, whether developed through conventional breeding or genetic transformation, will be he best solution for dealint with Acc. In Florida...

96

Citrus huanglongbing: a newly relevant disease presents unprecedented challenges.  

PubMed

Citrus huanglongbing (HLB) is one of the oldest citrus diseases and has been known for over a century. HLB is caused by 'Candidatus Liberibacter' spp. that are phloem-limited, fastidious ?-proteobacteria and infect hosts in different Kingdoms (i.e., Animalia and Plantae). When compared with well-characterized, cultivatable plant-pathogenic Gram-negative bacteria, the interactions of uncultured insect-vectored plant-pathogenic bacteria, including 'Ca. Liberibacter' spp., with their hosts remain poorly understood. 'Ca. Liberibacter' spp. have been known to cause HLB, which has been rapidly spreading worldwide, resulting in dramatic economic losses. HLB presents an unprecedented challenge to citrus production. In this review, we focus on the most recent research on citrus, 'Candidatus Liberibacter asiaticus', and psyllid interactions, specifically considering the following topics: evolutionary relationships among 'Ca. Liberibacter' spp., genetic diversity, host range, genome analysis, transmission, virulence mechanisms, and the ecological importance of HLB. Currently, no efficient management strategy is available to control HLB, although some promising progress has been made. Further studies are needed to understand citrus, 'Ca. L. asiaticus', and psyllid interactions to design innovative management strategies. Although HLB has been problematic for over a century, we can only win the battle against HLB with a coordinated and deliberate effort by the citrus industry, citrus growers, researchers, legislatures, and governments. PMID:23441969

Wang, Nian; Trivedi, Pankaj

2013-07-01

97

Modeling huanglongbing transmission within a citrus tree.  

PubMed

The citrus disease huanglongbing (HLB), associated with an uncultured bacterial pathogen, is threatening the citrus industry worldwide. A mathematical model of the transmission of HLB between its psyllid vector and citrus host has been developed to characterize the dynamics of the vector and disease development, focusing on the spread of the pathogen from flush to flush (a newly developing cluster of very young leaves on the expanding terminal end of a shoot) within a tree. This approach differs from that of prior models for vector-transmitted plant diseases where the entire plant is the unit of analysis. Dynamics of vector and host populations are simulated realistically as the flush population approaches complete infection. Model analysis indicates that vector activity is essential for initial infection but is not necessary for continued infection because infection can occur from flush to flush through internal movement in the tree. Flush production, within-tree spread, and latent period are the most important parameters influencing HLB development. The model shows that the effect of spraying of psyllids depends on time of initial spraying, frequency, and efficacy of the insecticides. Similarly, effects of removal of symptomatic flush depend on the frequency of removal and the time of initiation of this practice since the start of the epidemic. Within-tree resistance to spread, possibly affected by inherent or induced resistance, is a major factor affecting epidemic development, supporting the notion that alternate routes of transmission besides that by the vector can be important for epidemic development. PMID:22783015

Chiyaka, Christinah; Singer, Burton H; Halbert, Susan E; Morris, J Glenn; van Bruggen, Ariena H C

2012-07-10

98

Irrigation of Citrus with Citrus Processing Waste Water.  

National Technical Information Service (NTIS)

Several citrus scion-rootstock combinations were grown in greenhouses for 3 years and irrigated with treated waste water from two citrus processing plants in central Florida. No harmful effects were observed from the use of treated citrus waste water. Sup...

R. C. J. Koo

1974-01-01

99

Treatment of Citrus Processing Wastes.  

National Technical Information Service (NTIS)

Plant scale studies were performed to determine operational and treatment parameters for citrus processing wastewaters. Part I discusses treatment of concentrated citrus processing wastwaters combined with domestic sewage using a modified activated sludge...

J. B. Goodson J. J. Smith

1970-01-01

100

Citrus greening detection using airborne hyperspectral and multispectral imaging techniques  

Technology Transfer Automated Retrieval System (TEKTRAN)

Hyperspectral imaging can provide unique spectral signatures for diseased vegetation. Airborne multispectral and hyperspectral imaging can be used to detect potentially infected trees over a large area for rapid detection of infected zones. This paper proposes a method to detect the citrus greening...

101

Cloning and Sequencing of Candidatus liberibacter asiaticus Isolated from Citrus Trees in Malaysia  

Microsoft Academic Search

Candidatus liberibacter asiaticus, a causal agent of huanglongbing (HLB) disease of citrus in Malaysia, was detected in infected leaf samples collected from citrus growing areas in Selangor and Terangganu. The HLB bacterium was cloned and sequenced. The nucleotide sequences were 1324 and 1337 bp for GFB (greening fastidious bacterium) -T and-S isolate, respectively including the upstream and downstream nucleotides. It

A. KHAIRULMAZMI; S. KAMARUZAMAN; H. HABIBUDDIN; JUGAH KADIR; SYED OMAR; SYED RASTAN

102

Genome assembly of citrus leprosis virus nuclear type reveals a close association with orchid fleck virus.  

PubMed

The complete genome of citrus leprosis virus nuclear type (CiLV-N) was identified by small RNA sequencing utilizing leprosis-affected citrus samples collected from the state of Querétaro, Mexico. The nucleotide identity and phylogenetic analysis indicate that CiLV-N is very closely related to orchid fleck virus, which typically infects Cymbidium species. PMID:23887919

Roy, Avijit; Stone, Andrew; Otero-Colina, Gabriel; Wei, Gang; Choudhary, Nandlal; Achor, Diann; Shao, Jonathan; Levy, Laurene; Nakhla, Mark K; Hollingsworth, Charla R; Hartung, John S; Schneider, William L; Brlansky, Ronald H

2013-07-25

103

Citrus Proteins for Use in Field Detection of Citrus Blight Using Immunological Techniques.  

National Technical Information Service (NTIS)

The invention relates to purified and isolated citrus blight leaf proteins which are specific indicators of the presence of citrus blight. The isolated and purified citrus blight leaf proteins are extracted from citrus blighted leaves and have a molecular...

M. G. Bausher

1991-01-01

104

7 CFR 301.76-2 - Regulated articles for Asian citrus psyllid and citrus greening.  

Code of Federal Regulations, 2013 CFR

...Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE...DOMESTIC QUARANTINE NOTICES Citrus Greening and Asian Citrus...regulated articles for Asian citrus psyllid and citrus greening: (a) All plants and plant parts...

2013-01-01

105

Rice SERK1 gene positively regulates somatic embryogenesis of cultured cell and host defense response against fungal infection  

Microsoft Academic Search

Here we report on the isolation and characterization of a somatic embryogenesis receptor-like kinase (OsSERK1) gene in rice (Oryza sativa). The OsSERK1 gene belongs to a small subfamily of receptor-like kinase genes in rice and shares a highly conserved gene structure and extensive sequence homology with previously reported plant SERK genes. Though it has a basal level of expression in

H. Hu; L. Xiong; Y. Yang

2005-01-01

106

Citrus Leafminer Mating Disruption  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mating disruption targets a specific pest and has no negative impact on natural enemies, the environment, or agricultural workers. A flowable wax dispenser was tested for releasing the female sex pheromone of the citrus leafminer, Phyllocnistis citrella. These dispensers are biodegradable, inexpens...

107

Citrus stubborn disease (CSD)  

Technology Transfer Automated Retrieval System (TEKTRAN)

CSD is caused by Spiroplasma citri, a phloem-limited, cell-wall-less bacterium. S. citri is transmitted in a propagative, circulative manner by several leafhoppers including Circulifer tenellus and Scaphytopius nitridus in citrus-growing regions of California and Arizona and by C. haematoceps (syn....

108

Citrus tristeza virus-host interactions  

PubMed Central

Citrus tristeza virus (CTV) is a phloem-limited virus whose natural host range is restricted to citrus and related species. Although the virus has killed millions of trees, almost destroying whole industries, and continually limits production in many citrus growing areas, most isolates are mild or symptomless in most of their host range. There is little understanding of how the virus causes severe disease in some citrus and none in others. Movement and distribution of CTV differs considerably from that of well-studied viruses of herbaceous plants where movement occurs largely through adjacent cells. In contrast, CTV systemically infects plants mainly by long-distance movement with only limited cell-to-cell movement. The virus is transported through sieve elements and occasionally enters an adjacent companion or phloem parenchyma cell where virus replication occurs. In some plants this is followed by cell-to-cell movement into only a small cluster of adjacent cells, while in others there is no cell-to-cell movement. Different proportions of cells adjacent to sieve elements become infected in different plant species. This appears to be related to how well viral gene products interact with specific hosts. CTV has three genes (p33, p18, and p13) that are not necessary for infection of most of its hosts, but are needed in different combinations for infection of certain citrus species. These genes apparently were acquired by the virus to extend its host range. Some specific viral gene products have been implicated in symptom induction. Remarkably, the deletion of these genes from the virus genome can induce large increases in stem pitting (SP) symptoms. The p23 gene, which is a suppressor of RNA silencing and a regulator of viral RNA synthesis, has been shown to be the cause of seedling yellows (SY) symptoms in sour orange. Most isolates of CTV in nature are populations of different strains of CTV. The next frontier of CTV biology is the understanding how the virus variants in those mixtures interact with each other and cause diseases.

Dawson, W. O.; Garnsey, S. M.; Tatineni, S.; Folimonova, S. Y.; Harper, S. J.; Gowda, S.

2013-01-01

109

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

110

Chemical compounds effective against the citrus Huanglongbing bacterium 'Candidatus Liberibacter asiaticus' in planta.  

PubMed

Citrus Huanglongbing (HLB) is one of the most destructive diseases of citrus worldwide and is threatening the survival of the Floridian citrus industry. Currently, there is no established cure for this century-old and emerging disease. As a possible control strategy for citrus HLB, therapeutic compounds were screened using a propagation test system with 'Candidatus Liberibacter asiaticus'-infected periwinkle and citrus plants. The results demonstrated that the combination of penicillin and streptomycin (PS) was effective in eliminating or suppressing the 'Ca. L. asiaticus' bacterium and provided a therapeutically effective level of control for a much longer period of time than when administering either antibiotic separately. When treated with the PS, 'Ca. L. asiaticus'-infected periwinkle cuttings achieved 70% of regeneration rates versus <50% by other treatments. The 'Ca. L. asiaticus' bacterial titers in the infected periwinkle plants, as measured by quantitative real-time polymerase chain reaction, decreased significantly following root soaking or foliar spraying with PS. Application of the PS via trunk injection or root soaking also eliminated or suppressed the 'Ca. L. asiaticus' bacterium in the HLB-affected citrus plants. This may provide a useful tool for the management of citrus HLB and other Liberibacter-associated diseases. PMID:21834727

Zhang, Muqing; Powell, Charles A; Zhou, Lijuan; He, Zhenli; Stover, Ed; Duan, Yongping

2011-09-01

111

Pathogenesis and Ecology of Panicle Branch Blast of Rice Plant.  

National Technical Information Service (NTIS)

Contents: Development of diseases -- appearance of branch blast of rice plant from the beginning of disease to death of rice plant, effects of infected parts of panicle on death of panicle branch; Observations at experimental stations; Anatomical observat...

K. Hirano K. Goto

1966-01-01

112

Certification Programs for Citrus  

Microsoft Academic Search

Certification programs are important for the long term sustainability of citrus and other crops which are vegetatively propagated.\\u000a The certification program provides a basic platform for all integrated pest management practices, it is important for the\\u000a management of insect and fungal pests, and the program ensures that the grower is planting healthy germplasm of the highest\\u000a horticultural quality. Graft transmissible

Richard F. Lee

113

Studies of Seedling Yellows Amelioration of Citrus tristeza virus Strain Mixtures to Elucidate Mechanisms of Cross Protection  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus tristeza virus (CTV) cross-protection involves a mild strain of CTV preventing or interfering with infection or symptom expression by a severe strain. It is used to protect citrus when virulent stem pitting strains of CTV and efficient aphid vectors are endemic. However, the mode of action ...

114

Detection of a phytoplasma in citrus showing Huanglongbing (yellow shoot disease) symptoms in Guangdong, P. R. China  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus Huanglongbing (HLB) or yellow shoot disease (ex. greening disease) is highly destructive to citrus production worldwide. Understanding the etiology of HLB is critical for managing the disease. HLB is currently known to be associated with infection by Candidatus Liberibacter asiaticus in China...

115

Potential nutritional benefits of current citrus consumption  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus contains various nutrients and phytochemicals that may be beneficial for health. We collected citrus production and consumption data and estimated the amount of these compounds that are currently consumed. We then compared the amount of citrus and citrus-derived compounds that have been use...

116

A stable RNA virus-based vector for citrus trees  

SciTech Connect

Virus-based vectors are important tools in plant molecular biology and plant genomics. A number of vectors based on viruses that infect herbaceous plants are in use for expression or silencing of genes in plants as well as screening unknown sequences for function. Yet there is a need for useful virus-based vectors for woody plants, which demand much greater stability because of the longer time required for systemic infection and analysis. We examined several strategies to develop a Citrus tristeza virus (CTV)-based vector for transient expression of foreign genes in citrus trees using a green fluorescent protein (GFP) as a reporter. These strategies included substitution of the p13 open reading frame (ORF) by the ORF of GFP, construction of a self-processing fusion of GFP in-frame with the major coat protein (CP), or expression of the GFP ORF as an extra gene from a subgenomic (sg) mRNA controlled either by a duplicated CTV CP sgRNA controller element (CE) or an introduced heterologous CE of Beet yellows virus. Engineered vector constructs were examined for replication, encapsidation, GFP expression during multiple passages in protoplasts, and for their ability to infect, move, express GFP, and be maintained in citrus plants. The most successful vectors based on the 'add-a-gene' strategy have been unusually stable, continuing to produce GFP fluorescence after more than 4 years in citrus trees.

Folimonov, Alexey S.; Folimonova, Svetlana Y. [Department of Plant Pathology, University of Florida, Citrus Research and Education Center, 700 Experiment Station Road, Lake Alfred, FL 33850 (United States); Bar-Joseph, Moshe [The Volcani Center, Bet-Dagan 50259 (Israel); Dawson, William O. [Department of Plant Pathology, University of Florida, Citrus Research and Education Center, 700 Experiment Station Road, Lake Alfred, FL 33850 (United States)], E-mail: wodtmv@crec.ifas.ufl.edu

2007-11-10

117

7 CFR 301.76-3 - Quarantined areas; citrus greening and Asian citrus psyllid.  

Code of Federal Regulations, 2013 CFR

...quarantined for citrus greening or Asian citrus psyllid on the Plant Protection and Quarantine (PPQ) Web site: (http://www.aphis.usda.gov/plant_health/plant_pest_info/citrus_greening/index.shtml )....

2013-01-01

118

Enhancement of anti-complementary and radical scavenging activities in the submerged culture of Cordyceps sinensis by addition of citrus peel.  

PubMed

To investigate the optimal conditions for the production of Cordyceps sinensis by the submerged culture method, glucosamine and exopolysaccharide (EPS) productivities were determined in culture broth containing different carbon sources, principally rice bran and citrus peel. An optimal medium composition (1.5% rice bran, 0.5% molasses, 3% CSL, 0.1% KH(2)PO(4), and 0.05% MgSO(4)) and the optimal condition (25 degrees C and 5-6 d culture time) for high EPS productivity with potent immune-stimulating activities were obtained. The addition of citrus peel to the culture of C. sinensis under the optimized conditions improved EPS productivity and glucosamine content. Furthermore, anti-complementary activity was higher (58.0-80.8%) using citrus peel as compared to no addition of citrus peel (48.2-68.7%). Antioxidant activity (AEAC value) of the citrus peel culture was high (284.3-384.6 mg/100g) compared to that of the culture without citrus peel (142.8-219.5mg/100g), indicating that the citrus peel helped enhance the anti-complementary and antioxidant activities of C. sinensis. PMID:20299211

Choi, Jang Won; Ra, Kyung Soo; Kim, Seong Yeong; Yoon, Taek Joon; Yu, Kwang-Won; Shin, Kwang-Soon; Lee, Sam Pin; Suh, Hyung Joo

2010-03-17

119

Detection of mechanical and disease stresses in citrus plants by fluorescence spectroscopy  

NASA Astrophysics Data System (ADS)

We have investigated the detection of mechanical and disease stresses in citrus plants (Citrus limonia [L.] Osbeck) using laser-induced fluorescence spectroscopy. Due to its economic importance we have chosen to investigate the citrus canker disease, which is caused by the Xanthomonas axonopodis pv. citri bacteria. Mechanical stress was also studied because it plays an important role in the plant's infection by such bacteria. A laser-induced fluorescence spectroscopy system, composed of a spectrometer and a 532 nm10 mW excitation laser was used to perform fluorescence spectroscopy. The ratio of two chlorophyll fluorescence bands allows us to detect and discriminate between mechanical and disease stresses. This ability to discriminate may have an important application in the field to detect citrus canker infected trees.

Belasque, J., Jr.; Gasparoto, M. C. G.; Marcassa, L. G.

2008-04-01

120

Flavonoids in tropical citrus species.  

PubMed

HPLC with PDA and MS(2) detection was used to identify and quantify flavonoids in the tropical citrus species Citrus microcarpa , Citrus hystrix , Citrus medica var. 1 and 2, and Citrus suhuiensis . Most of these species contained high amounts of flavones, flavanones, and dihydrochalcone C- and/or O-glycosides, which were identified on the basis of HPLC retention times, cochromatography with available authentic standards, absorbance spectra, and mass spectral fragmentation patterns. Among the major compounds detected were apigenin-6,8-di-C-glucoside, apigenin-8-C-glucosyl-2?-O-rhamnoside, phloretin-3',5'-di-C-glucoside, diosmetin-7-O-rutinoside, hesperetin-7-O-neohesperidoside, and hesperetin-7-O-rutinoside. Most of the dihydrochalcone and flavone C-glycosides have not previously been detected in tropical citrus. C. microcarpa contained a high amount of phloretin-3',5'-di-C-glucoside. Most of the tropical citrus flavanones were neohesperidoside conjugates, which are responsible for imparting a bitter taste to the fruit. Only C. suhuiensis fruit contains rutinoside, a nonbitter conjugate. PMID:21978223

Roowi, Suri; Crozier, Alan

2011-10-19

121

Citrus Canker: Alternatives for Control  

NSDL National Science Digital Library

What do you do when county officials show up to cut down the orange trees in your backyard? What causes citrus canker and how is it spread? This plant pathogen was the first microbe to have its genome sequenced outside of the US. There is much to investigate before deciding on the best alternative for control. * examine international alternatives for the control of citrus canker

Linda Weinland (Edison College;Biology); Peter Woodruff (Champlain College;Biology); Margaret Waterman (Southeast Missouri State University;Biology); Ethel D. Stanley (Beloit College;Biology)

2006-05-20

122

Colonization of citrus and citrus-related germplasm by Diaphorina citri (Hemiptera: Psyllidae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Huanglongbing (HLB) is a serious and devastating disease of citrus caused by Candidatus Liberibacter spp. and vectored by the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae). The disease has the potential to greatly limit the production of citrus in Florida and other citrus gr...

123

CITRUS CANKER: PLANT PATHOLOGY VERSUS PUBLIC POLICY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Increasing international travel and trade has resulted in an unprecedented number of plant pathogen introductions, including Xanthomonas axonopodis pv citri, (Xac), the bacterium that causes citrus canker. The disease affects commercial and dooryard citrus, and has far-reaching politi...

124

The aconitate hydratase family from Citrus  

Microsoft Academic Search

BACKGROUND: Research on citrus fruit ripening has received considerable attention because of the importance of citrus fruits for the human diet. Organic acids are among the main determinants of taste and organoleptic quality of fruits and hence the control of fruit acidity loss has a strong economical relevance. In citrus, organic acids accumulate in the juice sac cells of developing

Javier Terol; Guillermo Soler; Manuel Talon; Manuel Cercos

2010-01-01

125

Transmission efficiency of Xylella fastidiosa by sharpshooters (Hemiptera: Cicadellidae) in coffee and citrus.  

PubMed

Xylella fastidiosa (Wells, Raju, Hung, Weisburg, Mandelco-Paul, and Brenner) is a bacterial pathogen transmitted by several sharpshooters in two tribes of Cicadellinae (Proconiini and Cicadellini). Here, we compared the transmission efficiency of X. fastidiosa in coffee (Coffea arabica L.) and citrus [Citrus sinensis (L.) Osbeck] by Cicadellini [Bucephalogonia xanthophis (Berg) and Dilobopterus costalimai Young] and Proconiini [Homalodisca ignorata Melichar and Oncometopia facialis (Signoret)] sharpshooters that occur in both crops. At different seasons, healthy adults of each species were submitted to a 48-h acquisition access period on citrus or coffee source plants infected with X. fastidiosa isolates that cause Citrus variegated chlorosis (CVC) and Coffee leaf scorch (CLS), respectively, and then confined on healthy seedlings of the corresponding host plant for a 48-h inoculation access period. No significant effect of inoculation season was observed when comparing infection rates of citrus or coffee plants inoculated by vectors at different times of the year. In citrus, the transmission rate by single insects was significantly higher for H. ignorata (30%) in relation to B. xanthophis (5%) and O. facialis (1.1%), but there was no difference among vector species in coffee, whose transmission rates ranged from 1.2 to 7.2%. Comparing host plants, H. ignorata was more effective in transmitting X. fastidiosa to citrus (30%) in relation to coffee (2.2%), whereas the other vectors transmitted the bacterium to both hosts with similar efficiencies. Despite these variations, vector efficiency in coffee and citrus is lower than that reported in other hosts. PMID:18767717

Marucci, Rosangela C; Lopes, João R S; Cavichioli, Rodney R

2008-08-01

126

Characterization of Citrus sinensis transcription factors closely associated with the non-host response to Xanthomonas campestris pv. vesicatoria.  

PubMed

Plants, when exposed to certain pathogens, may display a form of genotype-independent resistance, known as non-host response. In this study, the response of Citrus sinensis (sweet orange) leaves to Xanthomonas campestris pv. vesicatoria (Xcv), a pepper and tomato pathogenic bacterium, was analyzed through biochemical assays and cDNA microarray hybridization and compared with Asiatic citrus canker infection caused by Xanthomonas citri subsp. citri. Citrus leaves exposed to the non-host bacterium Xcv showed hypersensitive response (HR) symptoms (cell death), a defense mechanism common in plants but poorly understood in citrus. The HR response was accompanied by differentially expressed genes that are associated with biotic stress and cell death. Moreover, 58 transcription factors (TFs) were differentially regulated by Xcv in citrus leaves, including 26 TFs from the stress-associated families AP2-EREBP, bZip, Myb and WRKY. Remarkably, in silico analysis of the distribution of expressed sequence tags revealed that 10 of the 58 TFs, belonging to C2C2-GATA, C2H2, CCAAT, HSF, NAC and WRKY gene families, were specifically over-represented in citrus stress cDNA libraries. This study identified candidate TF genes for the regulation of key steps during the citrus non-host HR. Furthermore, these TFs might be useful in future strategies of molecular breeding for citrus disease resistance. PMID:23453188

Daurelio, Lucas D; Romero, María S; Petrocelli, Silvana; Merelo, Paz; Cortadi, Adriana A; Talón, Manuel; Tadeo, Francisco R; Orellano, Elena G

2013-02-26

127

Different Chitin Synthase Genes Are Required for Various Developmental and Plant Infection Processes in the Rice Blast Fungus Magnaporthe oryzae  

Microsoft Academic Search

Chitin is a major component of fungal cell wall and is synthesized by chitin synthases (Chs). Plant pathogenic fungi normally have multiple chitin synthase genes. To determine their roles in development and pathogenesis, we functionally characterized all seven CHS genes in Magnaporthe oryzae. Three of them, CHS1, CHS6, and CHS7, were found to be important for plant infection. While the

Ling-An Kong; Jun Yang; Guo-Tian Li; Lin-Lu Qi; Yu-Jun Zhang; Chen-Fang Wang; Wen-Sheng Zhao; Jin-Rong Xu; You-Liang Peng

2012-01-01

128

Flavanone Glycoside Biosynthesis in Citrus  

PubMed Central

Previous indirect evidence suggested that the biosynthesis of flavonoids in Citrus may not proceed via the usual chalcone synthase reaction and that glycosylation occurs during chalcone formation and not afterward, as has been reported in other species. We detected chalcone-synthase and UDP-glucose:flavanone-7-O-glucosyl-transferase activities in cell-free extracts of Citrus. The glucosylated flavanone was further rhamnosylated when exogenous UDP-glucose and NADPH were added to the extract. Chalcone-synthase activity was detected in cell-free extracts derived from young leaves and fruits. Young fruits (2 millimeter diameter) had the highest chalcone synthase activity. UDP-glucose:flavanone-7-O-glucosyl-transferase activity was measured in cell-free extracts derived from young leaves and fruits of Citrus mitis and Citrus maxima. The highest UDP-glucose:flavanone-7-O-glucosyl-transferase activity was found in young C. maxima leaves. These data indicate that Citrus contains a flavonoid pathway similar to that studied in other species. Images Figure 2 Figure 3

Lewinsohn, Efraim; Britsch, Lothar; Mazur, Yehuda; Gressel, Jonathan

1989-01-01

129

Genetically Engineered Rice Resistant to Rice Stripe Virus, an Insect Transmitted Virus  

Microsoft Academic Search

The coat protein (CP) gene of rice stripe virus was introduced into two japonica varieties of rice by electroporation of protoplasts. The resultant transgenic plants expressed the CP at high levels (up to 0.5% of total soluble protein) and exhibited a significant level of resistance to virus infection. Plants derived from selfed progeny of the primary transformants also expressed the

Takahiko Hayakawa; Yafeng Zhu; Kimiko Itoh; Yusuke Kimura; Takeshi Izawa; Ko Shimamoto; Shigemitsu Toriyama

1992-01-01

130

Principles of Carbon Catabolite Repression in the Rice Blast Fungus: Tps1, Nmr1-3, and a MATE-Family Pump Regulate Glucose Metabolism during Infection  

PubMed Central

Understanding the genetic pathways that regulate how pathogenic fungi respond to their environment is paramount to developing effective mitigation strategies against disease. Carbon catabolite repression (CCR) is a global regulatory mechanism found in a wide range of microbial organisms that ensures the preferential utilization of glucose over less favourable carbon sources, but little is known about the components of CCR in filamentous fungi. Here we report three new mediators of CCR in the devastating rice blast fungus Magnaporthe oryzae: the sugar sensor Tps1, the Nmr1-3 inhibitor proteins, and the multidrug and toxin extrusion (MATE)–family pump, Mdt1. Using simple plate tests coupled with transcriptional analysis, we show that Tps1, in response to glucose-6-phosphate sensing, triggers CCR via the inactivation of Nmr1-3. In addition, by dissecting the CCR pathway using Agrobacterium tumefaciens-mediated mutagenesis, we also show that Mdt1 is an additional and previously unknown regulator of glucose metabolism. Mdt1 regulates glucose assimilation downstream of Tps1 and is necessary for nutrient utilization, sporulation, and pathogenicity. This is the first functional characterization of a MATE–family protein in filamentous fungi and the first description of a MATE protein in genetic regulation or plant pathogenicity. Perturbing CCR in ?tps1 and MDT1 disruption strains thus results in physiological defects that impact pathogenesis, possibly through the early expression of cell wall–degrading enzymes. Taken together, the importance of discovering three new regulators of carbon metabolism lies in understanding how M. oryzae and other pathogenic fungi respond to nutrient availability and control development during infection.

Hartline, David; Quispe, Cristian F.; Madayiputhiya, Nandakumar; Wilson, Richard A.

2012-01-01

131

Chipping citrus wood for gasification  

SciTech Connect

Non-productive citrus trees were chipped with a portable fly-wheel-type chipper powered by a 45 kW engine. Chips were air dried under an open shed to 14% (w.b.) moisture content. By weight, approximately 50% of the total tree could be made into usable chips. The root system averaged 36% of the total tree weight.

Churchill, D.B.; Hedden, S.L.; Whitney, J.D.; Shaw, L.N.

1985-01-01

132

A multiplex polymerase chain reaction method for reliable, sensitive and simultaneous detection of multiple viruses in citrus trees  

Microsoft Academic Search

A multiplex polymerase chain reaction (mPCR) assay was developed to detect six RNA and one DNA citrus virus: Citrus leaf rugose virus (CLRV), Citrus psorosis virus (CPsV), Citrus tatter leaf virus (CTLV), Citrus tristeza virus (CTV), Citrus variegation virus (CVV), Citrus yellow mosaic virus (CYMV), and Indian citrus ringspot virus (ICRSV) from citrus plants. These seven viruses are classified in

Avijit Roy; Amer Fayad; G. Barthe; R. H. Brlansky

2005-01-01

133

78 FR 63369 - Citrus Canker, Citrus Greening, and Asian Citrus Psyllid; Interstate Movement of Regulated...  

Federal Register 2010, 2011, 2012, 2013

...provide adequate safeguards to prevent the spread of the three pests into currently unaffected...measures determined necessary to prevent the spread of the pest, or requiring the plants...regulations to prevent the interstate spread of citrus canker are contained...

2013-10-24

134

Citrus tristeza virus replicates and forms infectious virions in protoplasts of resistant citrus relatives  

Microsoft Academic Search

Citrus tristeza virus (CTV) is the most economically important viral disease of citrus worldwide. Cultivars with improved CTV tolerance or resistance are needed to manage CTV-induced diseases. The citrus relatives Poncirus trifoliata (L.) Raf., Swinglea glutinosa (Blanco) Merr., and Severinia buxifolia (Poir) Ten. are potential sources of CTV resistance, but their resistance mechanisms are poorly characterized. As a first step

Maria R. Albiach-Marti; Jude W. Grosser; Siddarame Gowda; Munir Mawassi; Tatineni Satyanarayana; Stephen M. Garnsey; William O. Dawson

2004-01-01

135

Huanglongbing, a systemic disease, restructures the bacterial community associated with citrus roots.  

PubMed

To examine the effect of pathogens on the diversity and structure of plant-associated bacterial communities, we carried out a molecular analysis using citrus and huanglongbing as a host-disease model. 16S rRNA gene clone library analysis of citrus roots revealed shifts in microbial diversity in response to pathogen infection. The clone library of the uninfected root samples has a majority of phylotypes showing similarity to well-known plant growth-promoting bacteria, including Caulobacter, Burkholderia, Lysobacter, Pantoea, Pseudomonas, Stenotrophomonas, Bacillus, and Paenibacillus. Infection by "Candidatus Liberibacter asiaticus" restructured the native microbial community associated with citrus roots and led to the loss of detection of most phylotypes while promoting the growth of bacteria such as Methylobacterium and Sphingobacterium. In pairwise comparisons, the clone library from uninfected roots contained significantly higher 16S rRNA gene diversity, as reflected in the higher Chao 1 richness estimation (P infected clone libraries, respectively. Similarly, the Shannon index of the uninfected clone library (4.46) was significantly higher than that of the infected clone library (2.61). Comparison of the uninfected clone library with the infected clone library using LIBSHUFF statistics showed a significant difference (P infection with the pathogen. These data indicate that infection of citrus by "Ca. Liberibacter asiaticus" has a profound effect on the structure and composition of the bacterial community associated with citrus roots. PMID:20382817

Trivedi, Pankaj; Duan, Yongping; Wang, Nian

2010-04-09

136

Huanglongbing, a Systemic Disease, Restructures the Bacterial Community Associated with Citrus Roots?  

PubMed Central

To examine the effect of pathogens on the diversity and structure of plant-associated bacterial communities, we carried out a molecular analysis using citrus and huanglongbing as a host-disease model. 16S rRNA gene clone library analysis of citrus roots revealed shifts in microbial diversity in response to pathogen infection. The clone library of the uninfected root samples has a majority of phylotypes showing similarity to well-known plant growth-promoting bacteria, including Caulobacter, Burkholderia, Lysobacter, Pantoea, Pseudomonas, Stenotrophomonas, Bacillus, and Paenibacillus. Infection by “Candidatus Liberibacter asiaticus” restructured the native microbial community associated with citrus roots and led to the loss of detection of most phylotypes while promoting the growth of bacteria such as Methylobacterium and Sphingobacterium. In pairwise comparisons, the clone library from uninfected roots contained significantly higher 16S rRNA gene diversity, as reflected in the higher Chao 1 richness estimation (P ? 0.01) of 237.13 versus 42.14 for the uninfected and infected clone libraries, respectively. Similarly, the Shannon index of the uninfected clone library (4.46) was significantly higher than that of the infected clone library (2.61). Comparison of the uninfected clone library with the infected clone library using LIBSHUFF statistics showed a significant difference (P ? 0.05). Quantitative PCR analysis revealed that the bacterial community changes not only qualitatively but also quantitatively. The relative proportions of different groups of bacteria changed significantly after infection with the pathogen. These data indicate that infection of citrus by “Ca. Liberibacter asiaticus” has a profound effect on the structure and composition of the bacterial community associated with citrus roots.

Trivedi, Pankaj; Duan, Yongping; Wang, Nian

2010-01-01

137

Diphenylurea Derivatives Induce Somatic Embryogenesis in Citrus  

Microsoft Academic Search

The present research investigates the possibility that three diphenylurea (DPU) derivatives, N-phenyl-N?-benzothiazol-6-ylurea (PBU), N,N?-bis-(2,3-methilendioxyphenyl)urea (2,3-MDPU) and N,N?-bis-(3,4-methilendioxyphenyl)urea (3,4-MDPU), stimulate the induction of somatic embryogenesis in three Citrus species. The hypothetical embryogenic activity was assessed using stigma and styles of Citrus myrtifolia Raf., Citrus madurensis Lour. and Citrus limon (L.) Burm. The three compounds influenced the production of somatic embryos differently

Angela Carra; Fabio De Pasquale; Ada Ricci; Francesco Carimi

2006-01-01

138

Citrus Allergy from Pollen to Clinical Symptoms  

PubMed Central

Allergy to citrus fruits is often associated with pollinosis and sensitization to other plants due to a phenomenon of cross-reactivity. The aims of the present study were to highlight the cross-reactivity among citrus and the major allergenic pollens/fruits, throughout clinical and molecular investigations, and to evaluate the sensitization frequency to citrus fruits in a population of children and adults with pollinosis. We found a relevant percentage of sensitisation (39%) to citrus fruits in the patients recruited and in all of them the IgE-mediated mechanism has been confirmed by the positive response to the prick-to-prick test. RT-PCR experiments showed the expression of Cit s 1, Cit s 3 and a profilin isoform, already described in apple, also in Citrus clementine pollen. Data of multiple sequence alignments demonstrated that Citrus allergens shared high percentage identity values with other clinically relevant species (i.e. Triticum aestivum, Malus domestica), confirming the possible cross-allergenicity citrus/grasses and citrus/apple. Finally, a novelty of the present work has been the expression of two phospholipaseA2 isoforms (PLA2 ? and ?) in Citrus as well as in Triticum pollens; being PLA2 able to generate pro-inflammatory factors, this enzyme could participate in the activation of the allergenic inflammatory cascade.

Iorio, Rosa Anna; Del Duca, Stefano; Calamelli, Elisabetta; Pula, Chiara; Lodolini, Magda; Scamardella, Fortuna; Pession, Andrea; Ricci, Giampaolo

2013-01-01

139

Citrus allergy from pollen to clinical symptoms.  

PubMed

Allergy to citrus fruits is often associated with pollinosis and sensitization to other plants due to a phenomenon of cross-reactivity. The aims of the present study were to highlight the cross-reactivity among citrus and the major allergenic pollens/fruits, throughout clinical and molecular investigations, and to evaluate the sensitization frequency to citrus fruits in a population of children and adults with pollinosis. We found a relevant percentage of sensitisation (39%) to citrus fruits in the patients recruited and in all of them the IgE-mediated mechanism has been confirmed by the positive response to the prick-to-prick test. RT-PCR experiments showed the expression of Cit s 1, Cit s 3 and a profilin isoform, already described in apple, also in Citrus clementine pollen. Data of multiple sequence alignments demonstrated that Citrus allergens shared high percentage identity values with other clinically relevant species (i.e. Triticum aestivum, Malus domestica), confirming the possible cross-allergenicity citrus/grasses and citrus/apple. Finally, a novelty of the present work has been the expression of two phospholipaseA2 isoforms (PLA2 ? and ?) in Citrus as well as in Triticum pollens; being PLA2 able to generate pro-inflammatory factors, this enzyme could participate in the activation of the allergenic inflammatory cascade. PMID:23308273

Iorio, Rosa Anna; Del Duca, Stefano; Calamelli, Elisabetta; Pula, Chiara; Lodolini, Magda; Scamardella, Fortuna; Pession, Andrea; Ricci, Giampaolo

2013-01-04

140

Development of rapid, sensitive and non-radioactive tissue-blot diagnostic method for the detection of citrus greening.  

PubMed

Citrus huanglongbing (HLB or citrus greening) is one of the most devastating diseases of citrus worldwide. The disease is caused by Gram-negative, phloem-limited ?-proteobacterium, 'Candidatus Liberibacter asiaticus', vectored by the psyllid, Diaphorina citri Kuwayama. Citrus plants infected by the HLB bacterium may not show visible symptoms sometimes for years following infection and non-uniform distribution within the tree makes the detection of the pathogen very difficult. Efficient management of HLB disease requires rapid and sensitive detection early in the infection followed by eradication of the source of pathogen and the vector. The polymerase chain reaction (PCR) based method is most commonly employed for screening the infected/suspected HLB plants and psyllids. This is time consuming, cumbersome and not practical for screening large number of samples in the field. To overcome this, we developed a simple, sensitive, non-radioactive, tissue-blot diagnostic method for early detection and screening of HLB disease. Digoxigenin labeled molecular probes specific to 'Ca. L. asiaticus' nucleotide sequences have been developed and used for the detection of the pathogen of the HLB disease. The copy number of the target genes was also assessed using real-time PCR experiments and the optimized real-time PCR protocol allowed positive 'Ca. L. asiaticus' detection in citrus samples infected with 'Ca. L. asiaticus' bacterium. PMID:23660459

Nageswara-Rao, Madhugiri; Miyata, Shin-Ichi; Ghosh, Dilip; Irey, Mike; Garnsey, Stephen M; Gowda, Siddarame

2013-05-06

141

Evaluating the effects of cold water diffusates against Xanthomonas oryzae Pv. Oryzae causing bacterial leaf blight (BLB) in rice  

Microsoft Academic Search

The crude extracts of 63 plants were used for testing antibacterial activity against Xanthmonas oryazae Pv. oryzae that causes bacterial leaf blight (BLB) in rice plants. Only ten aqueous extracts of botanicals (Thuja orientalis, Prunus domestica, Citrus limon, Allium sativum, Vitis vinefera, Mangifera indica, Phyllanthus emblica, and Terminalia chebula) showed maximum activity against Xanthmonas oryazae in a plate agar diffusion

Rukhsana Jabeen; Muhammad Ashraf; Iftikhar Ahmad

2009-01-01

142

Identification and characterization of the interaction between viroplasm-associated proteins from two different plant-infecting reoviruses and eEF-1A of rice.  

PubMed

A rice protein homologous to eukaryotic translation elongation factor 1A (eEF-1A) was found to interact with the Pns6 of rice ragged stunt virus (RRSV), the type member of the genus Oryzavirus, family Reoviridae, in yeast two-hybrid screening. The interaction between the rice protein, designated OseEF-1A, and RRSV Pns6 was confirmed by bimolecular fluorescence complementation. Besides Pns6, OseEF-1A also interacted with the viroplasm matrix protein, Pns10, of RRSV. When expressed together, OseEF-1A co-localized with RRSV Pns10 in epidermal cells of Nicotiana benthamiana. Pns6 of southern rice black-streaked dwarf virus (SRBSDV), a newly reported member of the genus Fijivirus, family Reoviridae, was the only non-structural SRBSDV protein studied here that also interacted with OseEF-1A. Like Pns6 of rice black-streaked dwarf virus (RBSDV), SRBSDV Pns6 interacted with itself and co-localized with Pns9-1 in N. benthamiana. In the presence of Pns6, OseEF-1A co-localized with Pns9-1, the putative viroplasm matrix protein of SRBSDV. PMID:23605590

Songbai, Zhang; Zhenguo, Du; Liang, Yang; Zhengjie, Yuan; Kangcheng, Wu; Guangpu, Li; Zujian, Wu; Lianhui, Xie

2013-04-19

143

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

144

Huanglongbing alters the structure and functional diversity of microbial communities associated with citrus rhizosphere.  

PubMed

The diversity and stability of bacterial communities present in the rhizosphere heavily influence soil and plant quality and ecosystem sustainability. The goal of this study is to understand how 'Candidatus Liberibacter asiaticus' (known to cause Huanglongbing, HLB) influences the structure and functional potential of microbial communities associated with the citrus rhizosphere. Clone library sequencing and taxon/group-specific quantitative real-time PCR results showed that 'Ca. L. asiaticus' infection restructured the native microbial community associated with citrus rhizosphere. Within the bacterial community, phylum Proteobacteria with various genera typically known as successful rhizosphere colonizers were significantly greater in clone libraries from healthy samples, whereas phylum Acidobacteria, Actinobacteria and Firmicutes, typically more dominant in the bulk soil were higher in 'Ca. L. asiaticus'-infected samples. A comprehensive functional microarray GeoChip 3.0 was used to determine the effects of 'Ca. L. asiaticus' infection on the functional diversity of rhizosphere microbial communities. GeoChip analysis showed that HLB disease has significant effects on various functional guilds of bacteria. Many genes involved in key ecological processes such as nitrogen cycling, carbon fixation, phosphorus utilization, metal homeostasis and resistance were significantly greater in healthy than in the 'Ca. L. asiaticus'-infected citrus rhizosphere. Our results showed that the microbial community of the 'Ca. L. asiaticus'-infected citrus rhizosphere has shifted away from using more easily degraded sources of carbon to the more recalcitrant forms. Overall, our study provides evidence that the change in plant physiology mediated by 'Ca. L. asiaticus' infection could elicit shifts in the composition and functional potential of rhizosphere microbial communities. In the long term, these fluctuations might have important implications for the productivity and sustainability of citrus-producing agro-ecosystems. PMID:21796220

Trivedi, Pankaj; He, Zhili; Van Nostrand, Joy D; Albrigo, Gene; Zhou, Jizhong; Wang, Nian

2011-07-28

145

Huanglongbing alters the structure and functional diversity of microbial communities associated with citrus rhizosphere  

PubMed Central

The diversity and stability of bacterial communities present in the rhizosphere heavily influence soil and plant quality and ecosystem sustainability. The goal of this study is to understand how ‘Candidatus Liberibacter asiaticus' (known to cause Huanglongbing, HLB) influences the structure and functional potential of microbial communities associated with the citrus rhizosphere. Clone library sequencing and taxon/group-specific quantitative real-time PCR results showed that ‘Ca. L. asiaticus' infection restructured the native microbial community associated with citrus rhizosphere. Within the bacterial community, phylum Proteobacteria with various genera typically known as successful rhizosphere colonizers were significantly greater in clone libraries from healthy samples, whereas phylum Acidobacteria, Actinobacteria and Firmicutes, typically more dominant in the bulk soil were higher in ‘Ca. L. asiaticus'-infected samples. A comprehensive functional microarray GeoChip 3.0 was used to determine the effects of ‘Ca. L. asiaticus' infection on the functional diversity of rhizosphere microbial communities. GeoChip analysis showed that HLB disease has significant effects on various functional guilds of bacteria. Many genes involved in key ecological processes such as nitrogen cycling, carbon fixation, phosphorus utilization, metal homeostasis and resistance were significantly greater in healthy than in the ‘Ca. L. asiaticus'-infected citrus rhizosphere. Our results showed that the microbial community of the ‘Ca. L. asiaticus'-infected citrus rhizosphere has shifted away from using more easily degraded sources of carbon to the more recalcitrant forms. Overall, our study provides evidence that the change in plant physiology mediated by ‘Ca. L. asiaticus' infection could elicit shifts in the composition and functional potential of rhizosphere microbial communities. In the long term, these fluctuations might have important implications for the productivity and sustainability of citrus-producing agro-ecosystems.

Trivedi, Pankaj; He, Zhili; Van Nostrand, Joy D; Albrigo, Gene; Zhou, Jizhong; Wang, Nian

2012-01-01

146

The relationship between phenolic content and Tylenchulus semipenetrans populations in nitrogen-amended citrus plants  

Microsoft Academic Search

SUMMARY Treatment with nitrogenous compounds, viz., ammonium nitrate, ammonium sulphate and urea as well as fu- migant DBCP on citrus seedlings showed an association between extensive synthesis of phenols in roots and the reduction in Tylenchulus semipenetrans in soi1 and roots. The content of phenols in treated roots was greater than in nematode infected untreated roots. The phenol content of

Taysir BADRA; Dawood M. ELGINDI

147

Genetic differentiation and biology of Citrus Tristeza virus populations spreading in California  

Technology Transfer Automated Retrieval System (TEKTRAN)

CTV strains were collected from more than 1500 CTV-infected trees in citrus groves in Tulare, Kern, Ventura, Riverside and San Diego Counties to assess molecular and biological properties of CTV strains currently in California. Tests included serology with MCA13, quantitative (q) real-time Reverse ...

148

Simultaneous detection of six citrus viroids and Apple stem grooving virus from citrus plants by multiplex reverse transcription polymerase chain reaction  

Microsoft Academic Search

We developed a multiplex reverse transcription polymerase chain reaction (RT-PCR) to detect six citrus viroids: Citrus exocortis viroid (CEVd), Citrus bent leaf viroid (CBLVd), Hop stunt viroid (HSVd), Citrus viroid III (CVd-III), Citrus viroid IV (CVd-IV) and Citrus viroid OS (CVd-OS) and Apple stem grooving virus (ASGV, synonym: Citrus tatter leaf virus (CTLV)) from citrus plants. The multiplex RT-PCR was

Takao Ito; Hiroyuki Ieki; Katsumi Ozaki

2002-01-01

149

Citrus leprosis and its status in Florida and Texas: past and present.  

PubMed

According to published reports from 1906 to 1968, leprosis nearly destroyed the Florida citrus industry prior to 1925. This was supported with photographs showing typical leprosis symptoms on citrus leaves, fruit, and twigs. Support for the past occurrence of citrus leprosis in Florida includes: (1) presence of twig lesions in affected orange blocks in addition to lesions on fruits and leaves and corresponding absence of similar lesions on grapefruit; (2) yield reduction and die-back on infected trees; and (3) spread of the disease between 1906 and 1925. Transmission electron microscopy (TEM) examination of tissue samples from leprosis-like injuries to orange and grapefruit leaves from Florida in 1997, and fruits from grapefruit and sweet orange varieties from Texas in 1999 and 2000 did not contain leprosis-like viral particles or viroplasm inclusions. In contrast, leprosis viroplasm inclusions were readily identified by TEM within green non-senescent tissues surrounding leprosis lesions in two of every three orange leaf samples and half of the fruit samples obtained from Piracicaba, Brazil. Symptoms of leprosis were not seen in any of the 24,555 orange trees examined across Florida during 2001 and 2002. The authors conclude that citrus leprosis no longer exists in Florida nor occurs in Texas citrus based on: (1) lack of leprosis symptoms on leaves, fruit, and twigs of sweet orange citrus varieties surveyed in Florida: (2) failure to find virus particles or viroplasm inclusion bodies in suspect samples from both Florida and Texas examined by TEM; (3) absence of documented reports by others on the presence of characteristic leprosis symptoms in Florida; (4) lack of its documented occurrence in dooryard trees or abandoned or minimal pesticide citrus orchard sites in Florida. In view of the serious threat to citrus in the U.S., every effort must be taken to quarantine the importation of both citrus and woody ornamental plants that serve as hosts for Brevipalpus phoenicis (Geijskes), B. californicus (Banks), and B. obovatus Donnadieu (Acari: Tenuipalpidae) from countries where citrus leprosis occurs. PMID:14756416

Childers, C C; Rodrigues, J C V; Derrick, K S; Achor, D S; French, J V; Welbourn, W C; Ochoa, R; Kitajima, E W

2003-01-01

150

Green synthesis of gold nanoparticles using Citrus fruits (Citrus limon, Citrus reticulata and Citrus sinensis) aqueous extract and its characterization.  

PubMed

This study reports the biological synthesis of gold nanoparticles by the reduction of HAuCl(4) by using citrus fruits (Citrus limon, Citrus reticulata and Citrus sinensis) juice extract as the reducing and stabilizing agent. A various shape and size of gold nanoparticles were formed when the ratio of the reactants were altered with respect to 1.0mM chloroauric acid solution. The gold nanoparticles obtained were characterized by UV-visible spectra, transmission electron microscopy (TEM) and X-ray diffraction (XRD). TEM studies showed the particles to be of various shapes and sizes and particle size ranges from 15 to 80 nm. Selected-area electron diffraction (SAED) pattern confirmed fcc phase and crystallinity of the particles. The X-ray diffraction analysis revealed the distinctive facets (111, 200, 220 and 222 planes) of gold nanoparticles. Dynamic light scattering (DLS) studies revealed that the average size for colloid gp(3) of C. limon, C. reticulata and C. sinensis are 32.2 nm, 43.4 nm and 56.7 nm respectively. The DLS graph showed that the particles size was larger and more polydispersed compared to the one observed by TEM due to the fact that the measured size also includes the bio-organic compounds enveloping the core of the Au NPs. Zeta potential value for gold nanoparticles obtained from colloid gp(3) of C. limon, C. reticulata and C. sinensis are -45.9, -37.9 and -31.4 respectively indicating the stability of the synthesized nanoparticles. Herein we propose a novel, previously unexploited method for the biological syntheses of polymorphic gold nanoparticles with potent biological applications. PMID:23211617

Sujitha, Mohanan V; Kannan, Soundarapandian

2012-09-28

151

Green synthesis of gold nanoparticles using Citrus fruits (Citrus limon, Citrus reticulata and Citrus sinensis) aqueous extract and its characterization  

NASA Astrophysics Data System (ADS)

This study reports the biological synthesis of gold nanoparticles by the reduction of HAuCl4 by using citrus fruits (Citrus limon, Citrus reticulata and Citrus sinensis) juice extract as the reducing and stabilizing agent. A various shape and size of gold nanoparticles were formed when the ratio of the reactants were altered with respect to 1.0 mM chloroauric acid solution. The gold nanoparticles obtained were characterized by UV-visible spectra, transmission electron microscopy (TEM) and X-ray diffraction (XRD). TEM studies showed the particles to be of various shapes and sizes and particle size ranges from 15 to 80 nm. Selected-area electron diffraction (SAED) pattern confirmed fcc phase and crystallinity of the particles. The X-ray diffraction analysis revealed the distinctive facets (1 1 1, 2 0 0, 2 2 0 and 2 2 2 planes) of gold nanoparticles. Dynamic light scattering (DLS) studies revealed that the average size for colloid gp3 of C. limon, C. reticulata and C. sinensis are 32.2 nm, 43.4 nm and 56.7 nm respectively. The DLS graph showed that the particles size was larger and more polydispersed compared to the one observed by TEM due to the fact that the measured size also includes the bio-organic compounds enveloping the core of the Au NPs. Zeta potential value for gold nanoparticles obtained from colloid gp3 of C. limon, C. reticulata and C. sinensis are -45.9, -37.9 and -31.4 respectively indicating the stability of the synthesized nanoparticles. Herein we propose a novel, previously unexploited method for the biological syntheses of polymorphic gold nanoparticles with potent biological applications.

Sujitha, Mohanan V.; Kannan, Soundarapandian

2013-02-01

152

[Climatic suitability of citrus in subtropical China].  

PubMed

By applying the theories of ecological suitability and the methods of fuzzy mathematics, this paper established a climatic suitability model for citrus, calculated and evaluated the climatic suitability and its spatiotemporal differences for citrus production in subtropical China, and analyzed the climatic suitability of citrus at its different growth stages and the mean climatic suitability of citrus in different regions of subtropical China. The results showed that the citrus in subtropical China had a lower climatic suitability and a higher risk at its flower bud differentiation stage, budding stage, and fruit maturity stage, but a higher climatic suitability and a lower risk at other growth stages. Cold damage and summer drought were the key issues affecting the citrus production in subtropical China. The citrus temperature suitability represented a latitudinal zonal pattern, i. e., decreased with increasing latitude; its precipitation suitability was high in the line of "Sheyang-Napo", medium in the southeast of the line, low in the northwest of the line, and non in high mountainous area; while the sunlight suitability was in line with the actual duration of sunshine, namely, higher in high-latitude areas than in low-latitude areas, and higher in high-altitude areas than in plain areas. Limited by temperature factor, the climatic suitability was in accordance with temperature suitability, i. e., south parts had a higher suitability than north parts, basically representing latitudinal zonal pattern. From the analysis of the inter-annual changes of citrus climatic suitability, it could be seen that the citrus climatic suitability in subtropical China was decreasing, and had obvious regional differences, suggesting that climate change could bring about the changes in the regions suitable for citrus production and in the key stages of citrus growth. PMID:21043095

Duan, Hai-Lai; Qian, Huai-Sui; Li, Ming-Xia; Du, Yao-Dong

2010-08-01

153

The development and ultrastructure of gum ducts in Citrus plants formed as a result of brown-rot gummosis  

Microsoft Academic Search

Summary Young stems ofCitrus plants were infected with the fungusPhytophthora citrophthora. The effect of the infection on gum duct development was studied. The following sequence of structural changes was observed in the cambial zone: 1. The middle lamellae between layers of xylem mother cells dissolve forming duct cavities. 2. The cells around the duct cavities differentiate into epithelial cells rich

Esther Gedalovich; Abraham Fahn

1985-01-01

154

Entomopathogenic fungus, Isaria fumosorosea, and aphid parasitoid, Lysiphlebus testaceipes, for managing infestations of Brown citrus aphid, Toxoptera citricida  

Technology Transfer Automated Retrieval System (TEKTRAN)

An insect-infecting fungal pathogen, (Isaria fumosorosea [Ifr])sold as the product PFR 97™ was shown to be effective at killing aphid pests while not decreasing beneficial parasitoids. The brown citrus aphid, Toxoptera citricida (Kirkaldy)(Hemiptera: Aphididae) spreads the plant-infecting virus, Cit...

155

Distribution and quantification of Candidatus Liberibacter americanus, agent of huanglongbing disease of citrus in São Paulo State, Brasil, in leaves of an affected sweet orange tree as determined by PCR  

Microsoft Academic Search

Huanglongbing (HLB), an insect-transmitted disease of citrus, known for many years in Asia and Africa, has appeared in the state of São Paulo State (SSP), Brazil, in 2004, and the state of Florida, USA, in 2005. HLB endangers the very existence of citrus, as trees infected with the bacterial pathogen, irrevocably decline. In the absence of curative procedures, control of

Diva C. Teixeira; Colette Saillard; Carole Couture; Elaine C. Martins; Nelson A. Wulff; Sandrine Eveillard-Jagoueix; Pedro T. Yamamoto; Antonio J. Ayres; Joseph M. Bové

2008-01-01

156

Identification of Yeasts Isolated from Varieties of Apples and Citrus Using PCR-Fragment Size Polymorphism and Sequencing of ITS1–5.8S-ITS2 region  

Microsoft Academic Search

Yeasts play a significant role in the nutrition industry, medicine, and biocontrol of plant pathogens. Certain isolates of yeasts act as antagonist agents in postharvest infections on fruits such as apples and citrus. The main goal of this study was identification of yeasts isolated from different types of Iranian apples and citrus using reliable molecular methods. For preliminary identification of

Mona Mokhtari; Hassan Reza Etebarian; Mohammad Razavi; Ali Heydari; Hossein Mirhendi

2012-01-01

157

Investigating alternatives to traditional insecticides: effectiveness of entomopathogenic fungi and Bacillus thuringiensis against citrus thrips and avocado thrips (Thysanoptera: Thripidae).  

PubMed

Citrus thrips, Scirtothrips citri (Moulton) (Thysanoptera: Thripidae), is a plant-feeding pest most widely recognized for causing damage to citrus (Citrus spp. L. [Rutaceae]) and mango (Mangifera indica L. [Anacardiaceae]) fruits. This insect has recently broadened its known host range to become a significant pest of California grown blueberries. Avocado thrips, Scirtothrips. perseae Nakahara (Thysanoptera: Thripidae), is a recent, invasive pest of California avocados, Persea americana Mill. (Laurales: Lauraceae). Effective alternatives to traditional pesticides are desirable for both pests to reduce impacts on natural enemies and broaden control options in an effort to minimize pesticide resistance via rotation of control materials. We evaluated Bacillus thuringiensis (Bt) subsp. israelensis proteins (Cyt 1A and Cry 11A, activated and inactivated) and multiple strains (GHA, 1741ss, SFBb1, S44ss, NI1ss, and 3769ss) of Beauveria bassiana (Balsamo) Vuillemin against both species. Avocado thrips and citrus thrips were not susceptible to either Bt protein tested, regardless of activation status. All strains of B. bassiana were able to infect both avocado thrips and citrus thrips. However, the commercially available GHA strain was the most effective strain against both species and had a faster rate of infection then the other strains tested. Citrus thrips were more susceptible than avocado thrips to all B. bassiana strains (LC50 and LC95 of 8.6 x 10(4) and 4.8 x 10(6) conidia per ml for citrus thrips, respectively). Investigation of citrus thrips field control using the GHA strain of B. bassiana is therefore justified. PMID:23448016

Zahn, Deane K; Morse, Joseph G

2013-02-01

158

7 CFR 319.56-38 - Citrus from Chile.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Citrus from Chile. 319.56-38 Section 319.56-38...Vegetables § 319.56-38 Citrus from Chile. Clementines (Citrus reticulata ...be imported into the United States from Chile, and grapefruit (Citrus paradisi...

2010-01-01

159

7 CFR 319.56-38 - Citrus from Chile.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Citrus from Chile. 319.56-38 Section 319.56-38...Vegetables § 319.56-38 Citrus from Chile. Clementines (Citrus reticulata ...be imported into the United States from Chile, and grapefruit (Citrus paradisi...

2013-01-01

160

Adventitious Citrus Juice Vesicles from Pre-Existing Juice Vesicles.  

National Technical Information Service (NTIS)

The invention comprises adventitious citrus juice vesicles having the unique characteristic that they branch out of pre-existing citrus juice vesicles. This is in contrast to tree-produced citrus juice vesicles which arise from the endocarp of the citrus ...

B. Tisserat

1989-01-01

161

Hydrogel substrate amendment alleviates drought effects on young citrus plants  

Microsoft Academic Search

Water deficits affect citrus physiology, yield, fruit size and quality. Citrus can respond to drought stress conditions through endogenous hormonal regulation of water status and leaf abscission. In this work, we assayed the efficiency of an amendment to soilless media in delaying the drought stress effect in young citrus seedlings and trees. Substrate amendment promoted plant survival of citrus seedlings

Vicent Arbona; Domingo J. Iglesias; Josep Jacas; Eduardo Primo-Millo; Manuel Talon; Aurelio Gómez-Cadenas

2005-01-01

162

Citrus Viruses in Guatemala: Application of Laboratory-Based Assays  

Technology Transfer Automated Retrieval System (TEKTRAN)

In preparation for a citrus certification in Guatemala, there was an urgent need to determine which graft transmissible citrus pathogens were present. Because of the lack of biological indicator plants, Citrus tristeza virus (CTV) and Xylella fastidiosa, causal agent for citrus variegated chlorosis...

163

Whitefly Pest Species (Homoptera: Aleyrodidae) on Citrus Trees  

Microsoft Academic Search

SUMMARY Today, the Citrus whitefly, Dialeurodes citri (Ashmead), is a very important pest on all Citrus species throughout the citrus growing areas in Croatia. It causes direct damage by sucking the plant juice from the leaves. Furthermore, immatures excrete honeydew that stimulates sooy mold. The presence of sooty mold on contaminated leaves interferes with the photosynthesis of plants. Citrus fruits

Sonja KAI

164

FIRST REPORT OF CITRUS BLIGHT IN COSTA RICA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus blight is a chronic decline disease of citrus which removes 5-10 percent of the trees from production annually in Florida and Brazil, respectively. In the northern citrus area of Costa Rica, trees are undergoing a decline having symptoms similar to the symptoms associated with citrus blight; ...

165

OCCURRENCE OF CITRUS BLIGHT IN COSTA RICA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Technical Abstract: Since 1997, citrus blight (CB) symptoms were observed in several groves in the northern region of Costa Rica, the country=s most important citrus area (more than 25,000 ha.). The symptoms include a general decline of the tree canopy with wilt, off-color leaves, leaf drop, twig...

166

Nitrogen best management practice for citrus trees  

Microsoft Academic Search

Soils in central Florida citrus production region are very sandy, hence are vulnerable to leaching of soluble nutrients and chemicals. The objective of this study was to develop nitrogen (N) and irrigation best management practices for citrus in sandy soils to maintain optimal crop yield and quality, and to minimize N leaching below the rootzone. A replicated plot experiment was

A. K. Alva; S. Paramasivam; A. Fares; T. A. Obreza; A. W. Schumann

2006-01-01

167

Cryopreservation and Cryotherapy of Citrus Cultivars  

Technology Transfer Automated Retrieval System (TEKTRAN)

Long-term conservation of Citrus clones can be accomplished by cryopreservation. Shoot tips will survive liquid nitrogen exposure and storage when appropriately desiccated and treated with cryoprotectant solutions. In our research, vegetative Citrus budwood is shipped from Riverside to Fort Collin...

168

QCM immunoassay for recombinant cysteine peptidase: a potential protein biomarker for diagnosis of citrus canker.  

PubMed

Citrus canker is one of the most important agricultural citrus diseases worldwide. It is caused by Xanthomonas citri subsp. citri (Xcc) bacterium that infects leaves and the fruits produce a cysteine peptidase (CPXaC), which makes it a potential target for the development of effective and rapid detection methods for citrus canker. We report here the studies on the development of piezoelectric immunoassay for CPXaC using a polyclonal antibody against CPXaC (anti-CPXaC). Three different strategies for covalent immobilization of anti-CPXaC on gold surfaces were evaluated by monitoring the frequency (?f) and energy dissipation (?D) variation in real time when 64.5×10(-8) mol L(-1) CPXaC was added. Anti-CPXaC immobilized with 11-mercaptoundecanoic acid (MUA) showed the best relation between the frequency and dissipation factor variation, and strong values for the kinetic and equilibrium binding constant were obtained. The immunosensor showed a detection limit of 13.0 nmol L(-1) with excellent specificity, showing no response for different proteins that include another cysteine peptidase that is used as a target to detect Xylella fastidiosa bacterium, responsible for another important citrus disease. These results provide good perspectives for the use of CPXaC as a new biomarker for citrus canker. PMID:23597909

Afonso, André S; Zanetti, Bianca F; Santiago, Adelita C; Henrique-Silva, Flavio; Mattoso, Luiz H C; Faria, Ronaldo C

2012-11-13

169

Tolerance of the trifoliate citrus hybrid US-897 (Citrus reticulata Blanco x Poncirus trifoliata L. Raf.) to Huanglongbing  

Technology Transfer Automated Retrieval System (TEKTRAN)

Huanglongbing (HLB) is a destructive disease of citrus in most citrus-producing countries worldwide. The disease, presumably caused by phloem-limited bacteria of the genus Candidatus Liberibacter, affects all known citrus species and citrus relatives with little known resistance. Typical disease s...

170

The plastome of Citrus . Physical map, variation among Citrus cultivars and species and comparison with related genera  

Microsoft Academic Search

A physical plastome map was constructed for Citrus aurantium, and the plastomes of species and cultivars of Citrus and of two Citrus relatives were analysed by Southern blot-hybridisation of labelled total tobacco cpDNA to digests of total Citrus DNA. A resemblance was found between the plastomes of cultivars of C. limon (lemon), C. sinensis (orange), C. aurantium (sour orange), C.

R. M. Green; A. Vardi; E. Galun

1986-01-01

171

Brassica cover cropping for management of sheath blight of rice  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sheath blight, caused by Rhizoctonia solani, is the most important disease limiting rice production in Texas and other rice-producing states. The fungal pathogen survives between crops as soilborne sclerotia and mycelium in infected plant debris. These sclerotia and colonized plant debris float on t...

172

CHARACTERIZATION OF RHIZOCTONIA SOLANI ISOLATES FROM RICE IN ARKANSAS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rhizoctonia solani causes sheath blight, one of the most serious diseases of rice. Over 200 isolates of Rhizoctonia-like fungi were obtained from infected rice samples in Arkansas, of which, 103 isolates were identified as R. solani using rDNA-ITS marker. The remaining isolates were either R. sativ...

173

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...

174

Inhibitory effects of Leuconostoc mesenteroides 1RM3 isolated from narezushi, a fermented fish with rice, on Listeria monocytogenes infection to Caco-2 cells and A/J mice.  

PubMed

Listeria monocytogenes causes listeriosis in humans mainly through consumption of ready-to-eat foods. Immunocompromised persons, the elderly, and pregnant women and their fetuses or newborns are at highest risk for the infection. To isolate probiotic lactic acid bacteria (LAB) with inhibitory effects against L. monocytogenes, we screened for acid and bile resistant LABs from narezushi, a traditional salted and long-fermented fish with cooked rice. Then, inhibitory effects of the selected LABs on L. monocytogenes invasion and infection of human enterocyte Caco-2 cells and Listeria-susceptible A/J mice were determined. From a total of 231 LAB isolates, we selected five acid and bile resistant isolates (four were Lactobacillus plantarum and one was Leuconostoc mesenteroides). Among the five isolates, Ln. mesenteroides (Lnm-1RM3) showed the highest inhibition against L. monocytogenes invasion into Caco-2 cells. In the case of L. monocytogenes orally infected A/J mice, recovery of the pathogen from the spleen was suppressed by drinking water containing 9 log CFU/ml of Lnm-1RM3 cells. The inhibitory effects were also shown by heat-killed Lnm-1RM3 cells. These results suggest that live and also heat-killed Lnm-1RM3 cell intake might prevent L. monocytogenes entero-gastric invasion and infection. PMID:22193553

Nakamura, Shinsuke; Kuda, Takashi; An, Choa; Kanno, Tomomi; Takahashi, Hajime; Kimura, Bon

2011-12-13

175

7 CFR 905.149 - Procedure for permitting growers to ship tree run citrus fruit.  

Code of Federal Regulations, 2010 CFR

...false Procedure for permitting growers to ship tree run citrus fruit. 905.149 Section 905.149...149 Procedure for permitting growers to ship tree run citrus fruit. (a) Tree run citrus fruit. Tree run citrus fruit as...

2010-01-01

176

7 CFR 905.149 - Procedure for permitting growers to ship tree run citrus fruit.  

Code of Federal Regulations, 2013 CFR

...false Procedure for permitting growers to ship tree run citrus fruit. 905.149 Section 905.149...149 Procedure for permitting growers to ship tree run citrus fruit. (a) Tree run citrus fruit. Tree run citrus fruit as...

2013-01-01

177

7 CFR 905.149 - Procedure for permitting growers to ship tree run citrus fruit.  

Code of Federal Regulations, 2010 CFR

...false Procedure for permitting growers to ship tree run citrus fruit. 905.149 Section 905.149...149 Procedure for permitting growers to ship tree run citrus fruit. (a) Tree run citrus fruit. Tree run citrus fruit as...

2009-01-01

178

Transcriptome profiling of citrus fruit response to huanglongbing disease.  

PubMed

Huanglongbing (HLB) or "citrus greening" is the most destructive citrus disease worldwide. In this work, we studied host responses of citrus to infection with Candidatus Liberibacter asiaticus (CaLas) using next-generation sequencing technologies. A deep mRNA profile was obtained from peel of healthy and HLB-affected fruit. It was followed by pathway and protein-protein network analysis and quantitative real time PCR analysis of highly regulated genes. We identified differentially regulated pathways and constructed networks that provide a deep insight into the metabolism of affected fruit. Data mining revealed that HLB enhanced transcription of genes involved in the light reactions of photosynthesis and in ATP synthesis. Activation of protein degradation and misfolding processes were observed at the transcriptomic level. Transcripts for heat shock proteins were down-regulated at all disease stages, resulting in further protein misfolding. HLB strongly affected pathways involved in source-sink communication, including sucrose and starch metabolism and hormone synthesis and signaling. Transcription of several genes involved in the synthesis and signal transduction of cytokinins and gibberellins was repressed while that of genes involved in ethylene pathways was induced. CaLas infection triggered a response via both the salicylic acid and jasmonic acid pathways and increased the transcript abundance of several members of the WRKY family of transcription factors. Findings focused on the fruit provide valuable insight to understanding the mechanisms of the HLB-induced fruit disorder and eventually developing methods based on small molecule applications to mitigate its devastating effects on fruit production. PMID:22675433

Martinelli, Federico; Uratsu, Sandra L; Albrecht, Ute; Reagan, Russell L; Phu, My L; Britton, Monica; Buffalo, Vincent; Fass, Joseph; Leicht, Elizabeth; Zhao, Weixiang; Lin, Dawei; D'Souza, Raissa; Davis, Cristina E; Bowman, Kim D; Dandekar, Abhaya M

2012-05-31

179

Citrus biotechnology: Achievements, limitations and future directions.  

PubMed

Citrus is one of the most important commercial and nutritional fruit crops in the world, hence it needs to be improved to cater to the diverse needs of consumers and crop breeders. Genetic manipulation through conventional techniques in this genus is invariably a difficult task for plant breeders as it poses various biological limitations comprising long juvenile period, high heterozygosity, sexual incompatibility, nucellar polyembryony and large plant size that greatly hinder cultivar improvement. Hence, several attempts were made to improve Citrus sps. by using various in vitro techniques. Citrus sps are widely known for their recalcitrance to transformation and subsequent rooting, but constant research has led to the establishment of improved protocols to ensure the production of uniformly transformed plants, albeit with relatively low efficiency, depending upon the genotype. Genetic modification through Agrobacterium-mediated transformation has emerged as an important tool for introducing agronomically important genes into Citrus sps. Somatic hybridization has been applied to overcome self and cross-incompatibility barriers and generated inter-specific and inter-generic hybrids. Encouraging results have been achieved through transgenics for resistance against viruses and bacteria, thereby augmenting the yield and quality of the fruit. Now, when major transformation and regeneration protocols have sufficiently been standardized for important cultivars, ongoing citrus research focuses mainly on incorporating such genes in citrus genotypes that can combat different biotic and abiotic stresses. This review summarizes the advances made so far in Citrus biotechnology, and suggests some future directions of research in this fruit crop. PMID:23572908

Singh, Sandeepa; Rajam, Manchikatla V

2009-05-14

180

Rice stripe virus 23.9?K protein aggregates and forms inclusion bodies in cultured insect cells and virus-infected plant cells  

Microsoft Academic Search

Summary. The genome of Rice stripe virus (RSV, genus Tenuivirus) contains seven open reading frames (ORFs). Little is known about the products of four of these ORFs, including the 23.9?K protein encoded by the virus-sense ORF of RNA3. Western blotting revealed that the 23.9?K protein was synthesized in the host plant and also in the planthopper vector of RSV. Using

M. Takahashi; C. Goto; K. Ishikawa; I. Matsuda; S. Toriyama; K. Tsuchiya

2003-01-01

181

Essential oil profiles of new Citrus hybrids, a tool for genetic citrus improvement  

Microsoft Academic Search

The essential oil composition of new Citrus hybrids obtained from the Citrus genetic improvement programs at the CRA-Centro di Ricerche per l’Agrumicoltura e le Colture Mediterranee of Acireale, Italy (CRA-ACM), were used to evaluate the fruit quality and to identify new valuable flavor components. The common objective of genetic improvement programs is to generate Citrus cultivars with a higher resistance

Simona Fabroni; Giuseppe Ruberto; Paolo Rapisarda

2012-01-01

182

Population structure of Citrus tristeza virus from field Argentinean isolates.  

PubMed

We studied the genetic variability of three genomic regions (p23, p25 and p27 genes) from 11 field Citrus tristeza virus isolates from the two main citrus growing areas of Argentina, a country where the most efficient vector of the virus, Toxoptera citricida, is present for decades. The pathogenicity of the isolates was determinated by biological indexing, single-strand conformation polymorphism analysis showed that most isolates contained high intra-isolate variability. Divergent sequence variants were detected in some isolates, suggesting re-infections of the field plants. Phylogenetic analysis of the predominant sequence variants of each isolate revealed similar grouping of isolates for genes p25 and p27. The analysis of p23 showed two groups contained the severe isolates. Our results showed a high intra-isolate sequence variability suggesting that re-infections could contribute to the observed variability and that the host can play an important role in the selection of the sequence variants present in these isolates. PMID:17999168

Iglesias, Néstor G; Gago-Zachert, Selma P; Robledo, Germán; Costa, Norma; Plata, María Inés; Vera, Osmar; Grau, Oscar; Semorile, Liliana C

2007-11-13

183

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

184

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.

185

PESTICIDE POISONINGS REPORTED BY FLORIDA CITRUS FIELDWORKERS  

EPA Science Inventory

In a 1981 survey of 1811 Florida citrus fieldworkers, 25 pesticide related poisoning incidents involving 29 fieldworkers were reported. Suspected poisonings were categorized into possible and confirmed poisonings, and from these reports it was possible to project an estimated 438...

186

A Polygalacturonase from Citrus Leaf Explants  

PubMed Central

The relationship between polygalacturonase activity and abscission of citrus leaf explants was studied. Determination of polygalacturonase activity in citrus tissues requires concentration of the enzyme, use of a proper assay method, and inhibition of an oxidase present in the extracts which oxidizes the reaction products of the polygalacturonase. The polygalacturonase from citrus leaf explants is an exopolygalacturonase and appears to be a soluble enzyme. Polygalacturonase activity increased during abscission of citrus leaf explants and was localized in the separation layer. Ethylene accelerated the increase in polygalacturonase activity, but its effect was evident only after at least an 8-hour lag period. 2,4-Dichlorophenoxyacetic acid and cycloheximide inhibited abscission and polygalacturonase activity. It is concluded that polygalacturonase, in addition to cellulase, plays a role in abscission. Images

Riov, J.

1974-01-01

187

The aconitate hydratase family from Citrus  

PubMed Central

Background Research on citrus fruit ripening has received considerable attention because of the importance of citrus fruits for the human diet. Organic acids are among the main determinants of taste and organoleptic quality of fruits and hence the control of fruit acidity loss has a strong economical relevance. In citrus, organic acids accumulate in the juice sac cells of developing fruits and are catabolized thereafter during ripening. Aconitase, that transforms citrate to isocitrate, is the first step of citric acid catabolism and a major component of the citrate utilization machinery. In this work, the citrus aconitase gene family was first characterized and a phylogenetic analysis was then carried out in order to understand the evolutionary history of this family in plants. Gene expression analyses of the citrus aconitase family were subsequently performed in several acidic and acidless genotypes to elucidate their involvement in acid homeostasis. Results Analysis of 460,000 citrus ESTs, followed by sequencing of complete cDNA clones, identified in citrus 3 transcription units coding for putatively active aconitate hydratase proteins, named as CcAco1, CcAco2 and CcAco3. A phylogenetic study carried on the Aco family in 14 plant species, shows the presence of 5 Aco subfamilies, and that the ancestor of monocot and dicot species shared at least one Aco gene. Real-time RT-PCR expression analyses of the three aconitase citrus genes were performed in pulp tissues along fruit development in acidic and acidless citrus varieties such as mandarins, oranges and lemons. While CcAco3 expression was always low, CcAco1 and CcAco2 genes were generally induced during the rapid phase of fruit growth along with the maximum in acidity and the beginning of the acid reduction. Two exceptions to this general pattern were found: 1) Clemenules mandarin failed inducing CcAco2 although acid levels were rapidly reduced; and 2) the acidless "Sucreña" orange showed unusually high levels of expression of both aconitases, an observation correlating with the acidless phenotype. However, in the acidless "Dulce" lemon aconitase expression was normal suggesting that the acidless trait in this variety is not dependent upon aconitases. Conclusions Phylogenetic studies showed the occurrence of five different subfamilies of aconitate hydratase in plants and sequence analyses indentified three active genes in citrus. The pattern of expression of two of these genes, CcAco1 and CcAco2, was normally associated with the timing of acid content reduction in most genotypes. Two exceptions to this general observation suggest the occurrence of additional regulatory steps of citrate homeostasis in citrus.

2010-01-01

188

Reservoir competence of the rice rat (Rodentia: Cricetidae) for Borrelia burgdorferi.  

PubMed

The reservoir competence of the rice rat, Oryzomys palustris, for Borrelia burgdorferi is described. Infected Ixodes scapularis Say (I. dammini, Spielman, Clifford, Piesman & Corwin) nymphs were used to infect animals. Borrelia infection was diagnosed by xenodiagnostic feeding of noninfected I. scapularis larvae and by reisolation of the spirochetes from blood and other tissues. Rice rats acquired B. burgdorferi and maintained spirochete infection for 5-9 wk. B. burgdorferi were cultured from samples of skin and urinary bladders from all animals killed on day 21 (three rats), 35 (three rats), or 56 (three rats) after infection. The spirochetes were also detected in blood samples obtained 1 and 2 wk after exposure. Spirochetes that persisted for 5 wk in rice rats did not lose their infectivity for golden Syrian hamsters. The prepatent period for infecting xenodiagnostic ticks was 1 wk. Overall, 75.6% of I. scapularis larvae (n = 694) that fed on infected rice rats acquired B. burgdorferi. Prevalence of infection reached 83% in ticks that fed on tick-exposed animals during the 2nd-4th wk, 68% during the 5th wk, and 17.4% during the 9th wk. The duration of rice rat infectivity for ticks exceeded 2 mo. I. scapularis nymphs infected as larvae on rice rats transmitted B. burgdorferi. Taken together, these studies confirm the reservoir competence of the rice rat for B. burgdorferi. PMID:7608919

Levin, M; Levine, J F; Apperson, C S; Norris, D E; Howard, P B

1995-03-01

189

Ecoport Slide Shows on the Internet Related to Citrus and Citrus Diseases  

Technology Transfer Automated Retrieval System (TEKTRAN)

The EcoPort website was launched in 2000 to provide a knowledge database of biodiversity. As of September 2005, the EcoPort website contained over one half million references, over 42,000 pictures and over 200 slide shows, of which 59 pertain to citrus and citrus virus and virus-like diseases. As ...

190

Characterization of grapefruit plants ( Citrus paradisi Macf.) transformed with citrus tristeza closterovirus genes  

Microsoft Academic Search

Grapefruit (Citrus paradisi Macf. cv Duncan) plants were transformed with several sequences from citrus tristeza closterovirus (CTV) that varied in terms of position in the CTV genome and virus strain origin in an attempt to obtain resistant plants. The sequences included the capsid protein gene from three different strains, a nontranslatable version of the capsid protein gene, the replicase (RdRp),

V. J. Febres; C. L. Niblett; R. F. Lee; G. A. Moore

2003-01-01

191

Citrus County Schools Copyright Guidelines Recommended by the Citrus County Association of School Media Specialists.  

ERIC Educational Resources Information Center

This document contains copyright guidelines determined appropriate for the Citrus County School System (Florida) by the Citrus County Association of School Media Specialists in May, 1992. These guidelines are based on interpretation and understanding of current copyright law as applied to education and implemented in school districts in the United…

Citrus County School District, Inverness, FL.

192

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

193

Transformation of rice mediated by Agrobacterium tumefaciens  

Microsoft Academic Search

Agrobacterium tumefaciens has been routinely utilized in gene transfer to dicotyledonous plants, but monocotyledonous plants including important cereals were thought to be recalcitrant to this technology as they were outside the host range of crown gall. Various challenges to infect monocotyledons including rice with Agrobacterium had been made in many laboratories, but the results were not conclusive until recently. Efficient

Yukoh Hiei; Toshihiko Komari; Tomoaki Kubo

1997-01-01

194

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

195

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

196

Detection of Phytophthora nicotianae and P. palmivora in citrus roots using PCR-RFLP in comparison with other methods  

Technology Transfer Automated Retrieval System (TEKTRAN)

Phytophthora nicotianae and P. palmivora are the most important soil-borne pathogens of citrus in Florida. These two species were detected and identified in singly and doubly infected plants using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of internal transcribed s...

197

Rice Yellow Mottle Virus stress responsive genes from susceptible and tolerant rice genotypes  

PubMed Central

Background The effects of viral infection involve concomitant plant gene variations and cellular changes. A simple system is required to assess the complexity of host responses to viral infection. The genome of the Rice yellow mottle virus (RYMV) is a single-stranded RNA with a simple organisation. It is the most well-known monocotyledon virus model. Several studies on its biology, structure and phylogeography have provided a suitable background for further genetic studies. 12 rice chromosome sequences are now available and provide strong support for genomic studies, particularly physical mapping and gene identification. Results The present data, obtained through the cDNA-AFLP technique, demonstrate differential responses to RYMV of two different rice cultivars, i.e. susceptible IR64 (Oryza sativa indica), and partially resistant Azucena (O. s. japonica). This RNA profiling provides a new original dataset that will enable us to gain greater insight into the RYMV/rice interaction and the specificity of the host response. Using the SIM4 subroutine, we took the intron/exon structure of the gene into account and mapped 281 RYMV stress responsive (RSR) transcripts on 12 rice chromosomes corresponding to 234 RSR genes. We also mapped previously identified deregulated proteins and genes involved in partial resistance and thus constructed the first global physical map of the RYMV/rice interaction. RSR transcripts on rice chromosomes 4 and 10 were found to be not randomly distributed. Seven genes were identified in the susceptible and partially resistant cultivars, and transcripts were colocalized for these seven genes in both cultivars. During virus infection, many concomitant plant gene expression changes may be associated with host changes caused by the infection process, general stress or defence responses. We noted that some genes (e.g. ABC transporters) were regulated throughout the kinetics of infection and differentiated susceptible and partially resistant hosts. Conclusion We enhanced the first RYMV/rice interaction map by combining information from the present study and previous studies on proteins and ESTs regulated during RYMV infection, thus providing a more comprehensive view on genes related to plant responses. This combined map provides a new tool for exploring molecular mechanisms underlying the RYMV/rice interaction.

Ventelon-Debout, Marjolaine; Tranchant-Dubreuil, Christine; Nguyen, Thi-Thu-Huang; Bangratz, Martine; Sire, Christelle; Delseny, Michel; Brugidou, Christophe

2008-01-01

198

MOLECULAR COEVOLUTION OF RICE RESISTANCE GENE PI-TA AND THE CORRESPONDING MAGNAPORTHE GRISEA AVIRULANCE GENE AVR-PITA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Understanding the population biology of both resistance genes and avirulence genes of rice blast fungus will allow the development of strategies to control rice blast disease. The Pi-ta gene in rice is effective in preventing the infection of M. grisea races containing the corresponding avirulence ...

199

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

200

Effects of the fungus Isaria fumosorosea (Hypocreales: Cordycipitaceae) on reduced feeding and mortality of the Asian citrus psyllid, Diaphorina citri (Hemiptera: Psyllidae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

The entomopathogenic fungi, Isaria fumosorosea Wize, reduced feeding of psyllids upon infection. Psyllids transmit the plant-infecting bacterium which causes Huanglongbing, in citrus trees, thus disruption of psyllid feeding may provide an added measure of control to reduce disease spread. The effe...

201

Citrus cultivars with high flavonoid contents in the fruits  

Microsoft Academic Search

The flavanone contents of some lesser known citrus cultivars grown in Cuba have been determined in research searching for citrus species\\/cultivars with high flavanone contents. The cultivar ‘Galleta’ of the mandarin (Citrus reticulata Blanco) has a higher hesperidin content than the hybrid mandarin ‘Nova’, which is currently being used for the commercial obtainment of this flavanone. The grapefruit cultivar ‘Isaac’

Ana Ortuño; Inès Reynaldo; Maria Dolores Fuster; Juana Botía; Damián Garcia Puig; Francisco Sabater; Angel García Lidón; Ignacio Porras; JoséAntonio Del Río

1997-01-01

202

COOPERATION IN THE CONSERVATION OF CITRUS GENETIC RESOURCES: RIVERSIDE, CALIFORNIA  

Technology Transfer Automated Retrieval System (TEKTRAN)

A consortium of cooperating programs for the conservation and utilization of genetic resources centers the University of California, Riverside (UCR). University units include the Citrus Clonal Protection Program (CCPP), Citrus Variety Collection (CVC), and Citrus Breeding Program (CBP). The USDA sup...

203

Converting citrus waste to ethanol and other co-products  

Technology Transfer Automated Retrieval System (TEKTRAN)

Conversion of citrus processing waste (CPW) generated during juice production into value added co-products is an important aspect of the juice industry as it offers a solution to waste disposal issues. Currently the practice of drying citrus waste to produce citrus pulp pellets (CPP) for use as catt...

204

CITRUS TRISTEZA VIRUS: EVOLUTION IN A HOST-LIMITED PATHOSYSTEM  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus tristeza virus(CTV) is a major viral pathogen of citrus, with a natural and experimental host range confined to members of the family Rutaceae, including the economically important genus Citrus. Experimental and agricultural paths of distribution of CTV are transmission by aphids and graft p...

205

7 CFR 319.56-41 - Citrus from Peru.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Citrus from Peru. 319.56-41...Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE...Vegetables § 319.56-41 Citrus from Peru. Grapefruit...control. In areas where citrus is produced for export...placed in fruit fly host plants at least 6...

2013-01-01

206

Absorption and Mobility of Boron in Young Citrus Plants  

Microsoft Academic Search

Boron (B) deficiency is widespread in Brazilian citrus orchards and has been considered an important soil constraint to citrus yield. The aim of this work was to study B uptake and its mobility in young citrus trees, under different B statuses, in two rootstocks. The experiment was carried out in a greenhouse, with ‘Valencia’ sweet orange trees budded on Rangpur

Rodrigo Marcelli Boaretto; José Antonio Quaggio; Francisco de Assis Alves Mourão Filho; Maria Fernanda Giné; Antonio Enedi Boaretto

2008-01-01

207

Conventional and transgenic resistance/tolerance to Huanglongbing in citrus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Huanglongbing (HLB) is severely impacting Florida citrus, and has been found in California and Texas. Citrus researchers are immersed in extensive and broad-ranging efforts to identify solutions to HLB. Previous research indicates susceptibility to HLB throughout cultivated citrus: in FL none are im...

208

Energy requirement and economic analysis of citrus production in Turkey  

Microsoft Academic Search

The aim of this research was to examine the energy requirements of the inputs and output in citrus production in the Antalya province of Turkey. Data for the production of citrus fruits (orange, lemon and mandarin) were collected from 105 citrus farms by using a face to face questionnaire method. The research results revealed that lemon production was the most

Burhan Ozkan; Handan Akcaoz; Feyza Karadeniz

2004-01-01

209

SPATIAL AND TEMPORAL ANALYSES OF CITRUS SUDDEN DEATH IN BRAZIL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus Sudden Death (CSD) is a disease of unknown etiology that affects sweet orange grafted on Rangpur lime and Volkamer lemon in Brazil. The spatial and temporal patterns of CSD was monitored in 116 citrus plots from 37 citrus farms located in 10 counties of Minas Gerais (MG) and São Paulo (SP) s...

210

Pesticide Use in United States Citrus Production, 1977.  

National Technical Information Service (NTIS)

Pesticide use in citrus production for 1977 was estimated for the three citrus producing regions in the United States (Florida, Texas, and California/Arizona). Citrus growers used an estimated 38.4 million pounds of active ingredient in approximately 8.2 ...

J. J. Haydu

1981-01-01

211

Ineffectiveness of pruning to control citrus huanglongbing caused by Candidatus Liberibacter americanus  

Microsoft Academic Search

The huanglongbing (HLB) disease of citrus trees, caused by Candidatus Liberibacter asiaticus and Ca. Liberibacter americanus, was first reported in Brazil in March, 2004. The presence of the disease has caused serious concerns\\u000a among growers. Pruning experiments were conducted to determine if removal of symptomatic branches or the entire canopy (decapitation)\\u000a would eliminate infected tissues and save HLB-affected trees. Pruning

Silvio Aparecido Lopes; Guilherme Fernando Frare; Pedro Takao Yamamoto; Antonio Juliano Ayres; José Carlos Barbosa

2007-01-01

212

Citrus exocortis viroid transmission through commercially-distributed seeds of Impatiens and Verbena plants  

Microsoft Academic Search

Surveys of Impatiens and Verbena species in local nurseries in Fredericton, Canada and Verbena species in New Delhi, India showed widespread infection of Citrus exocortis viroid (CEVd) in vegetatively-propagated and seed-grown plants. To determine viroid seed transmission, samples of eight varieties\\u000a of Impatiens and 11 varieties of Verbena were obtained from four commercial sources. All 19 samples collected contained viroid

Rudra P. Singh; Andrea D. Dilworth; Xiaoping Ao; Mathuresh Singh; Virendra K. Baranwal

2009-01-01

213

Agrobacterium -mediated transformation using embryogenic calli in Satsuma mandarin ( Citrus unshiu Marc.) cv. Miyagawa wase  

Microsoft Academic Search

Agrobacterium-mediated transformation in Satsuma mandarin (Citrus unshiu Marc.) cv. Miyagawa wase was achieved with reasonable transformation efficiency of about 22%, which was the percentage of\\u000a transgenic plantlets confirmed by genomic PCR (37 plantlets\\/168 hygromycin-resistant calli). Embryogenic calli of Miyagawa\\u000a wase were infected with Agrobacterium tumefaciens strain EHA105 harboring binary vector pCAMBIA1300 that contained miraculin gene (a taste-modifying protein) and hygromycin

Seong Beom Jin; Jeong Won Park; Hyeon Jin Sun; Su Hyun Yun; Hyo Yeon Lee; Dong Sun Lee; Quan Chun Hong; Yong Woo Kim; Key Zung Riu; Jae Hoon Kim

2011-01-01

214

Identification of two chilling-regulated 1-aminocyclopropane- 1-carboxylate synthase genes from citrus (Citrus sinensis Osbeck) fruit  

Microsoft Academic Search

Diurnal change in the temperature below or above 12.5 °C hastens the degreening of citrus peel and elicits the phytohormone ethylene production in citrus fruit. Ethylene triggers the degradation of chlorophyll and synthesis of carotenoids in citrus peel. To investigate if ethylene is required for the degreening of citrus peel elicited by low temperatures, we studied the chilling-regulated gene expression of

Wai Shing Wong; Wen Ning; Pei Lin Xu; Shain Dow Kung; Shang Fa Yang; Ning Li

1999-01-01

215

Molecular characterization of Wolbachia strains associated with the invasive Asian citrus psyllid Diaphorina citri in Brazil.  

PubMed

Wolbachia is a symbiont intensively studied due to its ability to interfere with their host's reproduction, and it has been recently proposed as an alternative tool to control insect pests or vectors of diseases. The Asian citrus psyllid Diaphorina citri is an important pest of citrus since it vectors the bacterium that causes the "Huanglongbing" disease in citrus. The frequency and diversity of Wolbachia associated with D. citri is unknown, limiting the utilization of Wolbachia as an alternative strategy for insect management. Thus, we aimed to determine the natural rate of infection, to characterize the Wolbachia strains associated with this psyllid by "multilocus sequencing typing" (MLST) and wsp analysis, and to verify the association of the symbiont to particular genotypes of the host. Analysis indicated Wolbachia infects 100 % of all specimens tested from all 15 sampled populations. MLST revealed the occurrence of five new sequence types (STs) of Wolbachia, while analysis based on the wsp sequences indicated only four different types of Wolbachia. ST-173 was predominant, while the remaining STs were population specific. Analysis of the host-symbiont relationship did not reveal any particular association of Wolbachia and haplotypes or a decrease in nucleotide diversity of D. citri in populations in which more than one ST was recorded. The consequences of the diversity of STs reported are still unknown, but the fact that Wolbachia infection is fixed and that there is one ST with a broad distribution highlights the use of this symbiont as an alternative strategy to control D. citri. PMID:23269454

Guidolin, A S; Cônsoli, F L

2012-12-28

216

Infection!  

NSDL National Science Digital Library

Play Infection! the game where you're the germ. And while you play, learn about the way your body fights infections.The game works best in Netscape 4 and Internet Explorer 4 or later. You will need to download Shockwave, but don't worry, you can do that right from the site.

York, Amercian M.

217

Betaines in fruits of Citrus genus plants.  

PubMed

Numerous compounds, many of them osmolytes, were quantified in natural juices and in frozen concentrate juices from fruits of plants of the Citrus genus. L-proline, N-methyl-L-proline (hygric acid), N,N-dimethyl-L-proline (stachydrine), 4-hydroxy-L-prolinebetaine (betonicine), 4-hydroxy-L-proline, ?-aminobutyric acid (Gaba), 3-carboxypropyltrimethylammonium (GabaBet), N-methylnicotinic acid (trigonelline), and choline in the fruit juices of yellow orange, blood orange, lemon, mandarin, bitter orange (Citrus aurantium), chinotto (Citrus myrtifolia), and grapefruit were analyzed by sensitive HPLC-ESI-tandem mass spectrometry procedure. It was found that the most represented osmolytes in the juices, that is, L-proline, stachydrine, and betonicine, can be quantified with minimal sample preparation and short analysis time (about 1 min) also by flow injection analysis (FIA) ESI-MS/MS with the same results as obtained by HPLC ESI-MS/MS. In all of the juices, discrete amounts of choline and trigonelline were present. Conversely, GabaBet was always below detection limits. Notably, N-methyl-L-proline and 4-hydroxy-L-prolinebetaine, which were discovered for the first time in the juice of bergamot (Citrus bergamia Risso et Poit), are also present in all of the citrus juices examined. PMID:21838291

Servillo, Luigi; Giovane, Alfonso; Balestrieri, Maria Luisa; Bata-Csere, Andrea; Cautela, Domenico; Castaldo, Domenico

2011-08-12

218

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

219

Influence of formulation and application method on the effectiveness of benzimidazole fungicides for controlling postharvest diseases of citrus fruits  

Microsoft Academic Search

Treatment of citrus fruits after harvest with benzimidazole fungicides suspended in water or incorporated in wax formulations\\u000a can control the development of several diseases of the fruit during storage and marketing. Residues of 1 mg fungicide\\/kg fruit\\u000a are sufficient to retard the development of latent infections of Phomopsis and Diplodia and to prevent wound infection by\\u000a Penicillium spp. Sporulation of

J. W. Eckert; M. J. Kolbezen

1977-01-01

220

Bioflavonoid profile of citrus juices from Greece.  

PubMed

High-performance liquid chromatography with confirmation by UV-visible photodiode array detector-positive electrospray ionization-mass spectrometry [HPLC-UV-vis-DAD-(+ESI)-MS] with enhanced fragmentation by appropriate adjustment of the cone voltage was used to determine bioflavonoid content of five citrus species (tangerine, sanguine, sour orange, lemon and grapefruit) cultivated in Greece which come from citrus varieties analyzed for the first time. The main groups of bioflavonoids found in the juice of the citrus species according to HPLC retention times, spectral data and literature references were O-glycosylated flavanones and flavones, C-glucosylated flavones, O-glucosylated flavones, O-C-glucosylated flavones like saponarin and a phenolic derivative. PMID:22334498

Anagnostopoulou, Maria A; Kefalas, Panagiotis

2012-02-15

221

Xanthomonas axonopodis pv. citri: factors affecting successful eradication of citrus canker.  

PubMed

SUMMARY Taxonomic status: Bacteria, Proteobacteria, gamma subdivision, Xanthomodales, Xanthomonas group, axonopodis DNA homology group, X. axonopodis pv. citri (Hasse) Vauterin et al. Microbiological properties: Gram negative, slender, rod-shaped, aerobic, motile by a single polar flagellum, produces slow growing, non-mucoid colonies in culture, ecologically obligate plant parasite. Host range: Causal agent of Asiatic citrus canker on most Citrus spp. and close relatives of Citrus in the family Rutaceae. Disease symptoms: Distinctively raised, necrotic lesions on fruits, stems and leaves. Epidemiology: Bacteria exude from lesions during wet weather and are disseminated by splash dispersal at short range, windblown rain at medium to long range and human assisted movement at all ranges. Crop loss: Severe infections cause defoliation, blemished fruit, premature fruit drop, die-back of twigs and general debilitation of the tree. Distribution: Citrus canker is not present in all subtropical to tropical regions of citriculture in the world, so considerable regulatory efforts are expended to prevent the introduction and spread of X. axonopodis pv. citri into areas in the Americas, Australia and elsewhere, with climates conducive to the disease. Importance: Limited strategies exist for suppression of citrus canker on more susceptible cultivars. Blemished fruit are unmarketable and exposed fruit are restricted in market access. The economic impact of loss of markets is much greater than that from yield and quality reductions of the crop. Useful websites: http://doacs.state.fl.us/canker, http://www.apsnet.org/education/lessonsplantpath/citruscanker/top.htm, http://www.apsnet.org/online/feature/citruscanker/, http://www.plantmanagementnetwork.org/pub/php/review/citruscanker/, http://www.abecitrus.com.br/fundecitrus.html, http://www.biotech.ufl.edu/PlantContainment/canker.htm, http://www.aphis.usda.gov/oa/ccanker/. PMID:20565577

Graham, James H; Gottwald, Tim R; Cubero, Jaime; Achor, Diann S

2004-01-01

222

Infections  

MedlinePLUS

... Fever and Taking Your Child's Temperature Flu Center Head Lice Is It a Cold or the Flu? Middle ... Worms, Lice, etc.) Amebiasis Ascariasis Bedbugs Chiggers Giardiasis Head Lice Infections That Pets Carry Malaria Pinworm Pubic Lice ...

223

Biogenic emissions from Citrus species in California  

NASA Astrophysics Data System (ADS)

Biogenic Volatile Organic Compounds (BVOC) emitted from plants are the dominant source of reduced carbon chemicals to the atmosphere and are important precursors to the photochemical production of ozone and secondary organic aerosols. Considering the extensive land used for agriculture, cultivated Citrus plantations may play an important role in the chemistry of the atmosphere especially in regions such as the Central Valley of California. Moreover, the BVOC emissions from Citrus species have not been characterized in detail and more species-specific inputs for regional models of BVOC emissions are needed. In this study, we measured the physiological parameters and emissions of the most relevant BVOC (oxygenated compounds, monoterpenes, and sesquiterpenes) for four predominant Citrus species planted in California ( Citrus sinensis var. 'Parent Navel', Citrus limon var. 'Meyer', Citrus reticulata var. 'W. Murcott' and 'Clementine'). We used two analytical techniques to measure a full range of BVOC emitted: Proton Transfer Reaction Mass Spectrometry (PTR-MS) and gas chromatography with mass spectrometry. Methanol, followed by acetone and acetaldehyde, were the dominant BVOC emitted from lemon and mandarin trees (basal emission rates up to 300 ng(C) g(DW) -1 h -1), while oxygenated monoterpenes, monoterpenes, and sesquiterpenes were the main BVOC emitted from orange trees (basal emission rates up to = 2500 ng(C) g(DW) -1 h -1). Light and temperature-dependent algorithms were better predictors of methanol, acetaldehyde, acetone, isoprene and monoterpenes for all the Citrus species. Whereas, temperature-dependent algorithms were better predictors of oxygenated monoterpenes, and sesquiterpenes. We observed that flowering increased emissions from orange trees by an order of magnitude with the bulk of BVOC emissions being comprised of monoterpenes, sesquiterpenes, and oxygenated monoterpenes. Chemical speciation of BVOC emissions show that the various classes of terpene emissions among all Citrus species are dominated by ocimenes, ?-caryophyllene, and linalool, respectively. In addition to utilizing our reported emission factors in BVOC emission models, we recommend that future BVOC emission models consider additional emissions from flowering and harvest, which occur seasonally and may have a significant impact on regional atmospheric chemistry.

Fares, Silvano; Gentner, Drew R.; Park, Jeong-Hoo; Ormeno, Elena; Karlik, John; Goldstein, Allen H.

2011-09-01

224

Movement of Regulated Articles From Citrus Greening and Asian Citrus Psyllid Quarantine Zones: Environmental Assessment.  

National Technical Information Service (NTIS)

This EA analyzes the environmental impacts anticipated from the implementation of a new Federal order for the domestic quarantine of citrus greening disease and ACP. The new Federal order contains the same chemical treatments as those evaluated in the Jan...

2007-01-01

225

77 FR 59709 - Citrus Greening and Asian Citrus Psyllid; Quarantine and Interstate Movement Regulations  

Federal Register 2010, 2011, 2012, 2013

...prohibitions on the movement of the article. Alternatively, if the article is sold in a box or container...citrus greening's vector for short-distance spread. Accordingly...interstate movement of the articles. Finally, we appreciate...

2012-10-01

226

The ER Chaperone LHS1 Is Involved in Asexual Development and Rice Infection by the Blast Fungus Magnaporthe oryzae[C][W][OA  

PubMed Central

In planta secretion of fungal pathogen proteins, including effectors destined for the plant cell cytoplasm, is critical for disease progression. However, little is known about the endoplasmic reticulum (ER) secretion mechanisms used by these pathogens. To determine if normal ER function is crucial for fungal pathogenicity, Magnaporthe oryzae genes encoding proteins homologous to yeast Lhs1p and Kar2p, members of the heat shock protein 70 family in Saccharomyces cerevisiae, were cloned and characterized. Like their yeast counterparts, both LHS1 and KAR2 proteins localized in the ER and functioned in an unfolded protein response (UPR) similar to the yeast UPR. Mutants produced by disruption of LHS1 were viable but showed a defect in the translocation of proteins across the ER membrane and reduced activities of extracellular enzymes. The ?lhs1 mutant was severely impaired not only in conidiation, but also in both penetration and biotrophic invasion in susceptible rice (Oryza sativa) plants. This mutant also had defects in the induction of the Pi-ta resistance gene–mediated hypersensitive response and in the accumulation of fluorescently-labeled secreted effector proteins in biotrophic interfacial complexes. Our results suggest that proper processing of secreted proteins, including effectors, by chaperones in the ER is requisite for successful disease development and for determining host-pathogen compatibility via the gene-for-gene interaction.

Yi, Mihwa; Chi, Myoung-Hwan; Khang, Chang Hyun; Park, Sook-Young; Kang, Seogchan; Valent, Barbara; Lee, Yong-Hwan

2009-01-01

227

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

228

Efficient production of transgenic citrus plants expressing the coat protein gene of citrus tristeza virus  

Microsoft Academic Search

The coat protein gene of citrus tristeza virus (CTV) has been introduced into Mexican lime (Citrus aurantifolia Swing.) plants by using an improved Agrobacterium-mediated genetic transformation system. Internodal stem segments from greenhouse-grown seedlings were co-cultivated with\\u000a A. tumefaciens strain EHA 105 carrying the binary plasmid pBI 121\\/CTV-CP in a medium rich in auxins that provided the explant cells with the

A. Domínguez; J. Guerri; M. Cambra; L. Navarro; P. Moreno; L. Peña

2000-01-01

229

Accumulation of the sesquiterpenes nootkatone and valencene by callus cultures of Citrus paradisi, Citrus limonia and Citrus aurantium  

Microsoft Academic Search

The production of the sesquiterpenes nootkatone and valencene by callus cultures of Citrus species is described. The levels of these compounds were examined by gas chromatography-mass spectrometry and their yields were compared with the amounts found in mature fruits. A simultaneous increase and decrease in the levels of nootkatone and valencene, respectively, were observed with the aging of callus cultures

J. A. del Río; A. Ortuño; D. García Puig; J. L. Iborra; F. Sabater

1991-01-01

230

Yield and quality responses of citrus (Citrus reticulate) and tea (Podocarpus fleuryi Hickel.) to compound fertilizers*  

PubMed Central

Experiments were carried out with citrus (Citrus reticulate) and tea (Podocarpus fleuryi Hickel.) to study the effects of compound fertilizers on their yields and quality. In the citrus experiment, application of compound fertilizers increased available P, K and Mg contents in soil but decreased alkali-hydrolyzable N contents in soil and N, P and K contents in leaves. In the tea experiment, application of compound fertilizers increased available P, K and Mg contents in soil and N, P, K and Mg contents in leaves but decreased alkali-hydrolyzable N in soil compared with the urea treatment. Application of compound fertilizers could improve the quality of citrus and tea, increase their yields and enhance their economical profits significantly. Compared with the control, application of compound fertilizers increased citrus yields by 6.31, 12.94 and 17.69 t/ha, and those of tea by 0.51, 0.86 and 1.30 t/ha, respectively. Correspondingly, profits were increased by 21.4% to 61.1% for citrus and by 10.0% to 15.7% for tea. Optimal rates of compound fertilizers were recommended for both crops.

Wang, Rui; Shi, Xue-gen; Wei, You-zhang; Yang, Xiao-e; Uoti, Juhani

2006-01-01

231

Volatile constituents of wild citrus Mangshanyegan (Citrus nobilis Lauriro) peel oil.  

PubMed

Volatiles of a wild mandarin, Mangshanyegan (Citrus nobilis Lauriro), were characterized by GC-MS, and their aroma active compounds were identified by aroma extract dilution analysis (AEDA) and gas chromatography-olfactometry (GC-O). The volatile profile of Mangshanyegan was compared with those of other four citrus species, Kaopan pummelo (Citrus grandis), Eureka lemon (Citrus limon), Huangyanbendizao tangerine (Citrus reticulata), and Seike navel orange (Citrus sinensis). Monoterpene hydrocarbons predominated in Mangshanyegan, in particular d-limonene and ?-myrcene, which accounted for 85.75 and 10.89% of total volatiles, respectively. Among the 12 compounds with flavor dilution factors (FD) = 27, 8 oxygenated compounds, including (Z)- and (E)-linalool oxides, were present only in Mangshanyegan. The combined results of GC-O, quantitative analysis, odor activity values (OAVs), and omission tests revealed that ?-myrcene and (Z)- and (E)-linalool oxides were the characteristic aroma compounds of Mangshanyegan, contributing to the balsamic and floral notes of its aroma. PMID:22352344

Liu, Cuihua; Cheng, Yunjiang; Zhang, Hongyan; Deng, Xiuxin; Chen, Feng; Xu, Juan

2012-03-02

232

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

233

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...

234

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

235

7 CFR 301.75-5 - Commercial citrus-producing areas.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Commercial citrus-producing areas. 301...Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE...DOMESTIC QUARANTINE NOTICES Citrus Canker Notice of Quarantine... § 301.75-5 Commercial citrus-producing areas....

2013-01-01

236

40 CFR 407.30 - Applicability; description of the citrus products subcategory.  

Code of Federal Regulations, 2010 CFR

...407.30 Applicability; description of the citrus products subcategory. The provisions of this...to discharges resulting from the processing of citrus into citrus products. When a plant is subject to effluent limitations covering...

2009-07-01

237

40 CFR 407.30 - Applicability; description of the citrus products subcategory.  

Code of Federal Regulations, 2012 CFR

...407.30 Applicability; description of the citrus products subcategory. The provisions of this...to discharges resulting from the processing of citrus into citrus products. When a plant is subject to effluent limitations covering...

2012-07-01

238

40 CFR 407.30 - Applicability; description of the citrus products subcategory.  

Code of Federal Regulations, 2010 CFR

...407.30 Applicability; description of the citrus products subcategory. The provisions of this...to discharges resulting from the processing of citrus into citrus products. When a plant is subject to effluent limitations covering...

2010-07-01

239

7 CFR 301.75-5 - Commercial citrus-producing areas.  

Code of Federal Regulations, 2010 CFR

...2009-01-01 false Commercial citrus-producing areas. 301...Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE...DOMESTIC QUARANTINE NOTICES Citrus Canker Notice of Quarantine... § 301.75-5 Commercial citrus-producing areas....

2009-01-01

240

7 CFR 301.75-5 - Commercial citrus-producing areas.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Commercial citrus-producing areas. 301...Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE...DOMESTIC QUARANTINE NOTICES Citrus Canker Notice of Quarantine... § 301.75-5 Commercial citrus-producing areas....

2010-01-01

241

7 CFR 457.121 - Arizona-California citrus crop insurance provisions.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Arizona-California citrus crop insurance provisions...REGULATIONS § 457.121 Arizona-California citrus crop insurance provisions. The Arizona-California citrus crop insurance provisions...

2013-01-01

242

7 CFR 301.75-17 - Funds for the replacement of certified citrus nursery stock.  

Code of Federal Regulations, 2013 CFR

...for the replacement of certified citrus nursery stock. 301.75-17 Section 301...for the replacement of certified citrus nursery stock. Subject to the availability of appropriated funds, a commercial citrus nursery may be eligible to receive funds to...

2013-01-01

243

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...

244

Infection!  

NSDL National Science Digital Library

This activity from the American Museum of Natural History's family magazine series is a board game in which kids learn how germs spread and infections take hold. The online activity begins with an overview of the many ways germs can enter your body and the body's first and second lines of defense. Kids then go to a page of directions for playing the online game, where they are also asked to select a microbe playing piece. As they move through the playing board, kids gain insight into how the body fights infection.

245

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

246

Green Fluorescent Detection of Fungal Colonization and Endopolygalacturonase Gene Expression in the Interaction of Alternaria citri with Citrus.  

PubMed

ABSTRACT Alternaria citri, a postharvest pathogen, produces endopolygalacturonase (endoPG) and causes black rot on citrus fruit. We previously described that an endoPG-disrupted mutant of Alternaria citri was significantly reduced in its ability to macerate plant tissue and cause black rot symptoms on citrus. In order to investigate colonization of citrus fruit tissues by Alternaria citri, pTEFEGFP carrying a green fluorescent protein (GFP) gene was introduced into wild-type Alternaria citri and its endoPG-disrupted mutant (M60). Green fluorescence was observed in spores, germ tubes, appressoria, and infection hyphae of transformants G1 (derived from wild type) and GM4 (derived from M60). Hyphae of G1 but not GM4 vertically penetrated the peel, but the hyphae of both G1 and GM4 spread equally in the juice sac area of citrus fruit. Green fluorescence of Alternaria citri transformant EPG7 carrying a GFP gene under control of the endoPG gene promoter of Alternaria citri was induced by pectin in the peel during the infection stage, but repressed completely in the juice sac area, likely by carbon catabolite repression by sugars in the juice. PMID:18943156

Isshiki, A; Ohtani, K; Kyo, M; Yamamoto, H; Akimitsu, K

2003-07-01

247

CHILLING INJURY AND POSTHARVEST DECAY IN CITRUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Hot water treatments have been studied and used as non-chemical methods to reduce postharvest decay and chilling injury (CI) in fresh citrus fruit. While many studies have been performed in Mediterranean climates, there exists relatively little work evaluating the effects of hot water on Florida gra...

248

CITRUS GERMPLASM RESOURCES AND THEIR USES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plant germplasm is living material, capable of being propagated, that contains genetic information that is passed down through time. Plant germplasm is the basis for plant agriculture and improvement. Citrus is a fruit crop of major importance in areas with a climate suitable for its growth. It has ...

249

Rheology and composition of processed citrus fiber  

Technology Transfer Automated Retrieval System (TEKTRAN)

While fibrous byproducts are abundant in supply, using them in food products in such a way to not degrade taste or texture can be challenging. Citrus fibers have been shown to have high water holding and viscous properties. However, to better incorporate dried orange pulp into foods, their propert...

250

Worker exposure to ethion in florida citrus  

Microsoft Academic Search

Dermal and respiratory exposure to ethion was determined for 17 men in eight spray crews in Florida citrus spray operations. Respiratory exposure was less than 1% of the total exposure. Hands represented 42% of the total body exposure for applicators and 76% for suppliers. At one location, suppliers exhibited a larger decrease in ChE activity than applicators. This difference appeared

G. A. Wojeck; H. N. Nigg; J. H. Stamper; D. E. Bradway

1981-01-01

251

Protection afforded citrus pesticide applicators by coveralls  

Microsoft Academic Search

Four airblast applicators of the pesticides dicofol and ethion to Florida citrus were monitored for pesticide exposure with pads placed inside and outside two types of protective coveralls. Hand exposure was not assessed. Pesticide accumulated uniformly over the coveralls' outer surface at a mean rate of 55 ±6 mg\\/hr. The penetration of ethion through a reusable treated twill suit was

H. N. Nigg; J. H. Stamper; E. P. Easter; W. D. Mahon; J. O. DeJonge

1990-01-01

252

Ecology of the Asian citrus pysllid  

Technology Transfer Automated Retrieval System (TEKTRAN)

Host selection by psyllids in general appears to involve taste rather than olfaction. Adults are often less discriminating than nymphs. A priori, there is good reason to doubt that Asian citrus psyllid (ACP) uses a long-distance sex pheromone or that ACP orients to host plant volatiles over large (m...

253

Founder lines for improved citrus biotechnology  

Technology Transfer Automated Retrieval System (TEKTRAN)

This article discusses the research needed to develop the RMCE strategy and molecular assays for site-specific recombinases as tools for genome manipulation. Explanation of genetic engineering used to generate transgenic citrus plants to exhibit a novel phenotype, but not to contain the recombinase...

254

Spot Chromatography Identification of Citrus Rootstocks  

Microsoft Academic Search

THE importance of knowing the variety of the rootstock in a citrus orchard is more than academic. The tolerance of an orange tree to infectious diseases; the size, the number and quality of its fruits; the palatability of its fresh and processed juice; its rate of growth and its expected longevity are all dynamically affected by the rootstock on which

Raymond M. Selle

1958-01-01

255

Use of Ozone in the Citrus Industry  

Microsoft Academic Search

The use of ozone for postharvest sanitation and decay control of fruits, vegetables and their products during handling, processing and storage has been investigated for commercial applications. Due to their significant contribution to world trade and human nutrition, citrus fruits are thought to be important commodities. Decay can be observed in these products because of microbial activity and ethylene accumulation

Hakan Karaca

2010-01-01

256

Advances in nitrogen fertigation of citrus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Advances in micro irrigation techniques, i.e. drip and under the tree sprinklers, have facilitated greater adoption of fertigation especially for perennial crops including citrus. It is generally believed that fertigation improves nutrient uptake efficiency, and increases the yield as well as crop q...

257

Citrus Huanglongbing: The Pathogen and Its Impact  

Technology Transfer Automated Retrieval System (TEKTRAN)

The article is a detailed review of the present status of huanglongbing (HLB) in the US and Brazil. HLB is known to be the most severe and destructive of all diseases of citrus greatly affecting yield and quality, and leads to tree death. It also has severe regulatory and quarantine implications a...

258

Bud emergence and shoot growth from mature citrus nodal stem segments  

Microsoft Academic Search

Bud emergence and shoot growth from adult phase citrus nodal cultures were studied using Citrus mitis (calamondin), Citrus paradisi (grapefruit), and Citrus sinensis (sweet orange). The effects of 6-benzyladenine (BA), indole 3-acetic acid (IAA), and citrus type on shoot quality and growth\\u000a of mature bud explants from greenhouse grown trees were determined using a 2-component mixture-amount × citrus type experiment.\\u000a BA increased

Mizuri Marutani-Hert; Terence J. Evens; Gregory T. McCollum; Randall P. Niedz

2011-01-01

259

Utilisation of citrus compost-based growing media amended with Trichodermaharzianum T-78 in Cucumismelo L. seedling production.  

PubMed

Two citrus composts (C1: composed of 40% citrus wastes, 20% sludge obtained from a citrus industry waste-water treatment facility and 40% green residues; C2: composed of 60% citrus wastes and 40% green residues, and no sludge) and their water extracts amended with Trichodermaharzianum T-78 (T. harzianum T-78) were assayed in order to verify if these composts could act as a partial substitute for peat-based growing media as well as enhance suppressiveness against Fusarium wilt in the production of melon (Cucumismelo L.) seedlings at greenhouse nurseries. Over a 43-day growth cycle of melon seedlings, measurements were taken of the nutriactive effect (the capability of a substrate to express additional and/or synergistic nutritional and biostimulating effects), the pathogen incidence (percentage of fresh weight loss of melon plants grown on treatments infected with Fusariumoxysporum with respect to the same treatment without inoculation of the phytopathogen) and the trend of the T.harzianum T-78 population. A nutriactive effect was observed in the tested citrus compost-based growing media (96% and 112% plant weight increase with respect to peat for C1Th and C2Th, respectively). Pathogen incidence was significantly lower in C2Th than peat (12% compared to 33%), while no difference was observed in C1Th. The T.harzianum T-78 population showed a significant decrease at the first sampling time compared to the initial quantity (from 10(6) to 10(5)CFUg(-1)), but later recovered over time. These results demonstrate that the combination of citrus compost and T.harzianum T-78 can be a viable alternative to peat and can minimise the application of chemicals necessary to control Fusarium wilt in greenhouse nurseries for melon seedling production. PMID:20096572

Lopez-Mondejar, R; Bernal-Vicente, A; Ros, M; Tittarelli, F; Canali, S; Intrigiolo, F; Pascual, J A

2010-01-21

260

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

261

Oxalic acid-induced resistance to Rhizoctonia solani in rice is associated with induction of phenolics, peroxidase and pathogenesis-related proteins  

Microsoft Academic Search

Oxalic acid (1 mM) when applied as a foliar spray to rice plants induced resistance to challenge infection with Rhizoctonia solani, the rice sheath blight pathogen. Maximum reduction in sheath blight incidence was observed when the plants were sprayed with oxalic acid three days before inoculation with the fungus. The biochemical alterations in rice plants treated with oxalic acid was

Jayaraman Jayaraj; Ranganathan Bhuvaneswari; Ramalingam Rabindran; Subbaratnam Muthukrishnan; Rethinasamy Velazhahan

2010-01-01

262

Relationship between gene responses and symptoms induced by Rice grassy stunt virus  

PubMed Central

Rice grassy stunt virus (RGSV) is a serious threat to rice production in Southeast Asia. RGSV is a member of the genus Tenuivirus, and it induces leaf yellowing, stunting, and excess tillering on rice plants. Here we examined gene responses of rice to RGSV infection to gain insight into the gene responses which might be associated with the disease symptoms. The results indicated that (1) many genes related to cell wall synthesis and chlorophyll synthesis were predominantly suppressed by RGSV infection; (2) RGSV infection induced genes associated with tillering process; (3) RGSV activated genes involved in inactivation of gibberellic acid and indole-3-acetic acid; and (4) the genes for strigolactone signaling were suppressed by RGSV. These results suggest that these gene responses to RGSV infection account for the excess tillering specific to RGSV infection as well as other symptoms by RGSV, such as stunting and leaf chlorosis.

Satoh, Kouji; Yoneyama, Kaori; Kondoh, Hiroaki; Shimizu, Takumi; Sasaya, Takahide; Choi, Il-Ryong; Yoneyama, Koichi; Omura, Toshihiro; Kikuchi, Shoshi

2013-01-01

263

Citrus alongside the sinking wreckage of MV Pacific Star in ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Citrus alongside the sinking wreckage of MV Pacific Star in the Pacific Ocean. Pacific Star's captain used his vessel to ram the cutter after he was ordered to stop and submit to inspection by a boarding team. Citrus was not seriously damaged in the collision. U.S. Coast Guard personnel recovered a large amount of marijuana from the wreckage - U.S. Coast Guard Cutter CITRUS, Coos Bay, Coos County, OR

264

Occurrence of Citrus psorosis virus in Campania, southern Italy  

Microsoft Academic Search

Citrus psorosis virus (CPsV), genus Ophiovirus, is associated with a severe disease of citrus worldwide. Double antibody sandwich (DAS) ELISA using a polyclonal antiserum, and triple antibody sandwich (TAS) ELISAs, employing the IgG monoclonal antibody (mab) 13C5, and the IgM mab 2A3, were used to detect CPsV in orchards of different citrus varieties in Campania, southern Italy. TAS ELISA with

D. Alioto; A. Troisi; A. Peluso; G. Quatrano; V. Masenga; R. G. Milne

2000-01-01

265

Ethylene association with chloride stress in citrus plants  

Microsoft Academic Search

Under non-chloride stress conditions, the chloride-sensitive citrus plant rootstock `Troyer' citrange (Poncirus trifoliata [L.] Rafinesque×Citrus sinensis [L.] Osbeck) accumulated 5-fold more chloride in their leaves [Bar, Y., Apelbaum, A., Kafkafi, U., Goren, R., 1996. Polyamines in chloride-stressed Citrus plants: alleviation of stress by nitrate supplementation via the irrigation water. J. Am. Soc. Horti. Sci., 121: 507–513.] and produced ethylene at

Y Bar; A Apelbaum; U Kafkafi; R Goren

1998-01-01

266

[Effect of ecological factors on citrus fruit quality].  

PubMed

This paper summarized the research advance on the physiological foundation of citrus fruit's major quality factors such as color formation and organic acid and sugar accumulation, and analyzed the effects of main ecological factors such as temperature, sunshine, water, soil, terrain and landforms on them. The existing problems and the research prospects of citrus ecology were expounded, and a useful proposal on the quality sub-distribution of citrus in China was put forward. PMID:15574012

Bao, Jiangfeng; Xia, Renxue; Peng, Shu'ang

2004-08-01

267

STUDIES ON ISOLATES OF RHIZOCTONIA SOLANI FROM ARKANSAS FOR MANAGEMENT OF RICE SHEATH  

Technology Transfer Automated Retrieval System (TEKTRAN)

The quantitative nature of the resistance to rice sheath blight caused by Rhizoctonia solani has made screening for resistance difficult. Studying field isolates may facilitate resistance screening. Among 200 Rhizoctonia-like fungi obtained from infected rice and two grass species from 19 counties...

268

Enumerative and binomial sampling plans for citrus mealybug (Homoptera: pseudococcidae) in citrus groves.  

PubMed

The spatial distribution of the citrus mealybug, Planococcus citri (Risso) (Homoptera: Pseudococcidae), was studied in citrus groves in northeastern Spain. Constant precision sampling plans were designed for all developmental stages of citrus mealybug under the fruit calyx, for late stages on fruit, and for females on trunks and main branches; more than 66, 286, and 101 data sets, respectively, were collected from nine commercial fields during 1992-1998. Dispersion parameters were determined using Taylor's power law, giving aggregated spatial patterns for citrus mealybug populations in three locations of the tree sampled. A significant relationship between the number of insects per organ and the percentage of occupied organs was established using either Wilson and Room's binomial model or Kono and Sugino's empirical formula. Constant precision (E = 0.25) sampling plans (i.e., enumerative plans) for estimating mean densities were developed using Green's equation and the two binomial models. For making management decisions, enumerative counts may be less labor-intensive than binomial sampling. Therefore, we recommend enumerative sampling plans for the use in an integrated pest management program in citrus. Required sample sizes for the range of population densities near current management thresholds, in the three plant locations calyx, fruit, and trunk were 50, 110-330, and 30, respectively. Binomial sampling, especially the empirical model, required a higher sample size to achieve equivalent levels of precision. PMID:16813342

Martínez-Ferrer, María Teresa; Ripollés, José Luís; Garcia-Marí, Ferran

2006-06-01

269

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

270

Sensitive and robust detection of citrus greening (huanglongbing) bacterium "Candidatus Liberibacter asiaticus" by DNA amplification with new 16S rDNA-specific primers.  

PubMed

Citrus greening disease is caused by "Candidatus Liberibacter spp.," including "Candidatus Liberibacter asiaticus (Las)." For detecting this disease, we designed new primers from the Las 16S rDNA and used a very small DNA template for PCR. More Las-infected tissues were detected with our primers than with the common primers. PMID:22728344

Fujikawa, Takashi; Iwanami, Toru

2012-06-21

271

Virus-induced gene silencing for rice using agroinoculation.  

PubMed

Virus-induced gene silencing (VIGS) is a reverse genetics technique that is based on the RNA-mediated defense against viruses in plants. VIGS is a method of gene knockdown triggered by a replicating viral nucleic acid engineered to carry a host gene to be silenced. While there are a number of excellent VIGS vectors available for dicots, only a few are available for monocots. Here, we describe the detailed method of the use of a newly developed VIGS vector for rice, based on the rice-infecting Rice tungro bacilliform virus, a pararetrovirus with dsDNA genome. Using a method based on Agrobacterium-mediated injection of the VIGS construct at the meristematic region of young rice plants, silencing of target genes can be achieved and the silenced phenotype can be visualized in 3 weeks. PMID:23386293

Purkayastha, Arunima; Sharma, Shweta; Dasgupta, Indranil

2013-01-01

272

Isolation and characterization of Aschersonia placenta from citrus orchards and its pathogenicity towards Dialeurodes citri (Ashmead).  

PubMed

For selecting potential biological agents to control Dialeurodes citri, a major insect pest in China's citrus orchards, 75 native Aschersonia isolates were selected from infected whiteflies in citrus orchards and were evaluated for virulence to third instar nymphs of D. citri at a concentration of 1 × 10(6)conidia/ml. The mortality rates of D. citri varied from 0% to 72.70%. Among the 75 Aschersonia isolates, three (HB10, HB12 and ZJ9) were the most virulent and pathogenic to D. citri and caused more than 69% mortality. The 50% lethal concentration (LC(50)) values of them were 1.86 × 10(6), 3.40 × 10(6) and 6.81 × 10(6)conidia/ml, respectively. The three isolates also produced conidia abundantly on potato dextrose agar medium (3.95 × 10(6), 6.19 × 10(6) and 7.34 × 10(6)conidia/cm(2), respectively). They were identified to be Aschersonia placenta based on their morphological analysis. Phylogenetic analysis showed that these three highly virulent Aschersonia isolates belong to a strongly supported clade that includes two other A. placenta isolates obtained from Vietnam and Thailand. In summary, these results indicate the possibility of developing the three most virulent A. placenta isolates as microbiological control agents against citrus whitefly. PMID:23160084

Wang, Pingping; Song, Xuhong; Zhang, Hongyu

2012-11-15

273

Immunodiagnosis of Citrus leprosis virus C using a polyclonal antibody to an expressed putative coat protein.  

PubMed

Citrus leprosis virus C (CiLV-C), a causal agent for citrus leprosis disease, is present in South and Central America and is a threat for introduction into the U.S. citrus industry. A specific, inexpensive and reliable antibody based detection system is needed for the rapid identification of CiLV-C. The CiLV-C is very labile and has not been purified in sufficient amount for antibody production. The p29 gene of CiLV-C genome that codes for the putative coat protein (PCP) was codon optimized for expression in Escherichia coli and synthesized in vitro. The optimized gene was sub-cloned into the bacterial expression vector pDEST17 and transferred into E. coli BL21AI competent cells. The expression of PCP containing N-terminal His-tag was optimized by induction with l-arabinose. Induced cells were disrupted by sonication and expressed PCP was purified by affinity chromatography using Ni-NTA agarose. The purified expressed PCP was then used as an immunogen for injections into rabbits to produce polyclonal antibody (PAb). The PAb specific to the expressed PCP was identified using Western blotting. The antibody was successfully used to detect CiLV-C in the symptomatic CiLV-C infected tissues using double antibody sandwich-enzyme-linked-immunosorbent (DAS-ELISA), indirect ELISA and dot-blot immunoassay (DBIA) formats. PMID:23911294

Choudhary, Nandlal; Roy, Avijit; Guillermo, Leon M; Picton, D D; Wei, G; Nakhla, M K; Levy, L; Brlansky, R H

2013-07-30

274

Convenient Detection of the Citrus Greening (Huanglongbing) Bacterium 'Candidatus Liberibacter asiaticus' by Direct PCR from the Midrib Extract  

PubMed Central

A phloem-limited bacterium, ‘Candidatus Liberibacter asiaticus’ (Las) is a major pathogen of citrus greening (huanglongbing), one of the most destructive citrus diseases worldwide. The rapid identification and culling of infected trees and budwoods in quarantine are the most important control measures. DNA amplification including conventional polymerase chain reaction (PCR) has commonly been used for rapid detection and identification. However, long and laborious procedures for DNA extraction have greatly reduced the applicability of this method. In this study, we found that the Las bacterial cells in the midribs of infected leaves were extracted rapidly and easily by pulverization and centrifugation with mini homogenization tubes. We also found that the Las bacterial cells in the midrib extract were suitable for highly sensitive direct PCR. The performance of direct PCR using this extraction method was not inferior to that of conventional PCR. Thus, the direct PCR method described herein is characterized by its simplicity, sensitivity, and robustness, and is applicable to quarantine testing.

Fujikawa, Takashi; Miyata, Shin-Ichi; Iwanami, Toru

2013-01-01

275

Cellular automata model for citrus variegated chlorosis  

NASA Astrophysics Data System (ADS)

A cellular automata model is proposed to analyze the progress of citrus variegated chlorosis epidemics in São Paulo orange plantations. In this model epidemiological and environmental features, such as motility of sharpshooter vectors that perform Lévy flights, level of plant hydric and nutritional stress, and seasonal climatic effects, are included. The observed epidemic data were quantitatively reproduced by the proposed model on varying the parameters controlling vector motility, plant stress, and initial population of diseased plants.

Martins, M. L.; Ceotto, G.; Alves, S. G.; Bufon, C. C. B.; Silva, J. M.; Laranjeira, F. F.

2000-11-01

276

Nitrogen best management practice for citrus trees  

Microsoft Academic Search

Elevated levels of nitrate-nitrogen (NO3-N) in the surficial aquifer above the drinking water quality standard, i.e. maximum contaminant limit (MCL; 10mgL?1), have been reported in some part of central Florida citrus production regions. Soils in this region are very sandy (sand content >95%), hence are vulnerable to leaching of soluble nutrients and chemicals below the rooting depth of the trees.

A. K. Alva; S. Paramasivam; T. A. Obreza; A. W. Schumann

2006-01-01

277

Review Adverse Effects of Salinity on Citrus  

Microsoft Academic Search

Due to the rapid expansion of irrigated agriculture, efficient use of the limited water resources in arid and semi-arid regions is becoming more and more vital. However, water salinity is a major problem due to its negative influence on the yields of many crops. It reduces citrus trees' growth and causes physiological disorders. Salt-stress lowers net CO2 assimilation, stomatal conductance,

ADNAN AL-YASSIN

278

Reference genes for accurate transcript normalization in citrus genotypes under different experimental conditions.  

PubMed

Real-time reverse transcription PCR (RT-qPCR) has emerged as an accurate and widely used technique for expression profiling of selected genes. However, obtaining reliable measurements depends on the selection of appropriate reference genes for gene expression normalization. The aim of this work was to assess the expression stability of 15 candidate genes to determine which set of reference genes is best suited for transcript normalization in citrus in different tissues and organs and leaves challenged with five pathogens (Alternaria alternata, Phytophthora parasitica, Xylella fastidiosa and Candidatus Liberibacter asiaticus). We tested traditional genes used for transcript normalization in citrus and orthologs of Arabidopsis thaliana genes described as superior reference genes based on transcriptome data. geNorm and NormFinder algorithms were used to find the best reference genes to normalize all samples and conditions tested. Additionally, each biotic stress was individually analyzed by geNorm. In general, FBOX (encoding a member of the F-box family) and GAPC2 (GAPDH) was the most stable candidate gene set assessed under the different conditions and subsets tested, while CYP (cyclophilin), TUB (tubulin) and CtP (cathepsin) were the least stably expressed genes found. Validation of the best suitable reference genes for normalizing the expression level of the WRKY70 transcription factor in leaves infected with Candidatus Liberibacter asiaticus showed that arbitrary use of reference genes without previous testing could lead to misinterpretation of data. Our results revealed FBOX, SAND (a SAND family protein), GAPC2 and UPL7 (ubiquitin protein ligase 7) to be superior reference genes, and we recommend their use in studies of gene expression in citrus species and relatives. This work constitutes the first systematic analysis for the selection of superior reference genes for transcript normalization in different citrus organs and under biotic stress. PMID:22347455

Mafra, Valéria; Kubo, Karen S; Alves-Ferreira, Marcio; Ribeiro-Alves, Marcelo; Stuart, Rodrigo M; Boava, Leonardo P; Rodrigues, Carolina M; Machado, Marcos A

2012-02-09

279

Enhancement or attenuation of disease by deletion of genes from Citrus tristeza virus.  

PubMed

Stem pitting is a common virus-induced disease of perennial woody plants induced by a range of different viruses. The phenotype results from sporadic areas of the stem in which normal xylem and phloem development is prevented during growth of stems. These alterations interfere with carbohydrate transport, resulting in reduced plant growth and yield. Citrus tristeza virus (CTV), a phloem-limited closterovirus, induces economically important stem-pitting diseases of citrus. CTV has three nonconserved genes (p33, p18, and p13) that are not related to genes of other viruses and that are not required for systemic infection of some species of citrus, which allowed us to examine the effect of deletions of these genes on symptom phenotypes. In the most susceptible experimental host, Citrus macrophylla, the full-length virus causes only very mild stem-pitting symptoms. Surprisingly, we found that certain deletion combinations (p33 and p18 and/or p13) induced greatly increased stem-pitting symptoms, while other combinations (p13 or p13 plus p18) resulted in reduced stem pitting. These results suggest that the stem-pitting phenotype, which is one of more economically important disease phenotypes, can result not from a specific sequence or protein but from a balance between the expression of different viral genes. Unexpectedly, using green fluorescent protein-tagged full-length virus and deletion mutants (CTV9?p33 and CTV9?p33?p18?p13), the virus was found at pitted areas in abnormal locations outside the normal ring of phloem. Thus, increased stem pitting was associated not only with a prevention of xylem production but also with a proliferation of cells that supported viral replication, suggesting that at random areas of stems the virus can elicit changes in cellular differentiation and development. PMID:22593155

Tatineni, Satyanarayana; Dawson, William O

2012-05-16

280

Increasing antibiotic activity against a multidrug-resistant Acinetobacter spp by essential oils of Citrus limon and Cinnamomum zeylanicum  

Microsoft Academic Search

The genus Acinetobacter has gained importance in recent years due to involvement in serious infections and antimicrobial resistance. Many plants have been evaluated not only for direct antimicrobial activity, but also as resistance modifying agents. The Essential oil of Citrus limon (EOCL) addition at 156.25?µgmL (MIC\\/8) sub-inhibitory concentration in the growth medium led to MIC decrease for amikacin, imipenem and

Felipe Queiroga Sarmento Guerra; Juliana Moura Mendes; Janiere Pereira de Sousa; Maria F. B. Morais-Braga; Bernadete Helena Cavalcante Santos; Henrique Douglas Melo Coutinho; Edeltrudes de Oliveira Lima

2011-01-01

281

Impact of Ozonated Water on the Quality and Shelflife of Fresh Citrus Fruit, Stone Fruit, and Table Grapes  

Microsoft Academic Search

Spores of fungi that cause postharvest decay of fresh fruit die rapidly in ozonated water. We determined the impact of sporocidal or higher O3 doses on fruit shelf-life and quality. Green mold and sour rot on citrus fruit, caused by Penicillium digitatum and Geotrichum citri-aurantii, respectively, were not reduced by 20 min immersion in 10 ppm O3. These fungi infect through wounds;

J. L. Smilanick; D. M. Margosan; F. Mlikota Gabler

2002-01-01

282

Differential response of stomata to air humidity in the parasitic mistletoe ( Phthirusa pyrifolia ) and its host, mandarin orange ( Citrus resitulata )  

Microsoft Academic Search

Measurements of CO2 and H2O exchange rate and the calculated leaf conductance of attached leaves were conducted over a range of leaf-to-air vapour pressure difference (VPD) (1.5 to 5.5 kPa) to compare the response of the parasitic mistletoe, Phthirusa pyrifolia, with that of its host, the mandarin orange, Citrus reticulata. Seedlings of the host infected with the parasite were grown

Mabrouk A. El-Sharkawy; James H. Cock; Ana Pilar Hernandez

1986-01-01

283

Candidatus Liberibacter americanus induces significant reprogramming of the transcriptome of the susceptible citrus genotype  

PubMed Central

Background Citrus huanglongbing (HLB) disease is caused by endogenous, phloem-restricted, Gram negative, uncultured bacteria named Candidatus Liberibacter africanus (CaLaf), Ca. L. asiaticus (CaLas), and Ca. L. americanus (CaLam), depending on the continent where the bacteria were first detected. The Asian citrus psyllid vector, Diaphorina citri, transmits CaLas and CaLam and both Liberibacter species are present in Brazil. Several studies of the transcriptional response of citrus plants manifesting HLB symptoms have been reported, but only for CaLas infection. This study evaluated the transcriptional reprogramming of a susceptible genotype of sweet orange challenged with CaLam, using a customized 385K microarray containing approximately 32,000 unigene transcripts. We analyzed global changes in gene expression of CaLam-infected leaves of sweet orange during the symptomatic stage of infection and compared the results with previously published microarray studies that used CaLas-infected plants. Twenty candidate genes were selected to validate the expression profiles in symptomatic and asymptomatic PCR-positive leaves infected with CaLas or CaLam. Results The microarray analysis identified 633 differentially expressed genes during the symptomatic stage of CaLam infection. Among them, 418 (66%) were upregulated and 215 (34%) were down regulated. Five hundred and fourteen genes (81%) were orthologs of genes from Arabidopsis thaliana. Gene set enrichment analysis (GSEA) revealed that several of the transcripts encoded transporters associated with the endomembrane system, especially zinc transport. Among the most biologically relevant gene transcripts in GSEA were those related to signaling, metabolism and/or stimulus to hormones, genes responding to stress and pathogenesis, biosynthesis of secondary metabolites, oxidative stress and transcription factors belonging to different families. Real time PCR of 20 candidate genes validated the expression pattern of some genes in symptomatic and asymptomatic leaves infected with CaLam or CaLas. Conclusions Many gene transcripts and biological processes are significantly altered upon CaLam infection. Some of them had been identified in response to CaLas infection, while others had not been previously reported. These data will be useful for selecting target genes for genetic engineering to control HLB.

2013-01-01

284

EVALUATION OF DNA AMPLIFICATION METHODS FOR IMPROVED DETECTION OF CANDIDATUS LIBERIBACTER SPECIES ASSOCIATED WITH CITRUS HUANGLONGBING  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus huanglongbing (HLB), also known as citrus greening or citrus yellow shoot, is considered the most serious disease of citrus worldwide. The disease has Asian, African and American forms caused by Candidatus Liberibacter asiaticus, Ca. L. africanus and Ca. L. americanus, respectively, which can...

285

Characterization of the antioxidant properties of phenolic extracts from some citrus peels  

Microsoft Academic Search

This study sought to determine the distribution of free and bound phenolics in some Nigerian citrus peels [orange (Citrus sinensis), grapefruit (Citrus paradisii) and shaddock (Citrus maxima)] and characterize the antioxidant properties. The free phenolics were extracted with 80% acetone, while the bound phenolics\\u000a were extracted from the alkaline and acid hydrolyzed residue with ethyl acetate. Free phenolic extracts had

G. Oboh; A. O. Ademosun

286

World Fresh Citrus Fruit Production and Trade Statistics, Jungle 1984.  

National Technical Information Service (NTIS)

The world's fresh citrus trade volume has doubled over the past two decades. Most of this expansion occurred during the 1960's, a period in which exports of all citrus types increased sharply. In the 1970's, the annual rate of growth slowed as a result of...

1984-01-01

287

Diversity and Phylogenetic Relationships of the Citrus Varieties Collection  

Technology Transfer Automated Retrieval System (TEKTRAN)

Twenty-five simple sequence repeat (SSR) markers were used to detect molecular polymorphisms among 370 Citrus accessions from the Citrus Variety Collection located at The University of California, Riverside. The number of alleles detected per locus ranged from three to thirty. A total of 298 alle...

288

DIVERSITY AND PHYLOGENETIC RELATIONSHIPS OF THE CITRUS VARIETY COLLECTION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Twenty-five Simple Sequence Repeat (SSR) markers were used to detect molecular polymorphisms among 370 Citrus accessions from the Citrus Variety Collection located at the University of California, Riverside. The number of alleles detected per locus ranged from three to thirty. A total of 298 alleles...

289

The David Rosen lecture: biological control in citrus  

Microsoft Academic Search

David Rosen was a scientist, professor, administrator, philosopher, organizer, family man, and friend to many. He made numerous and remarkable contributions to biological control in citrus. Much of his research was on the biosystematics of Aphytis parasitoids, but he also held strong convictions about the importance of biological control in citrus integrated pest management (IPM), and carried out research on

Marjorie A Hoy

2000-01-01

290

New enzymes for hydrolysis and fermentation of citrus waste  

Technology Transfer Automated Retrieval System (TEKTRAN)

The expense involved to dry citrus processing waste into citrus pulp pellets (CPP) for use as a cattle feed continues to increase with rising fuel costs. While there have also been recent increases in the value of CPP, this value fluctuates considerably and does not always cover processing costs. Th...

291

FIRST REPORT OF CITRUS BLIGHT IN COSTA RICA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus blight (CB), causing a chronic decline of citrus, has been an important disease in Florida for over 100 years. CB was first reported in Brazil in the 1980s and is now responsible for the removal of nearly 10% of the trees from production annually. No causal agent has been identified, but CB h...

292

EVALUATION OF WASTE CITRUS ACTIVATED SLUDGE IN POULTRY FEEDS  

EPA Science Inventory

Experiments were conducted on chick broilers and hens to determine the metabolizable energy of citrus sludge. A determination of metabolizable energy values showed that the values decreased as the level of citrus sludge in the diet increased. A series of protein levels were fed t...

293

Induction of triploid Citrus plants from endosperm calli in vitro  

Microsoft Academic Search

Triploid hybrid Citrus plants were regenerated by somatic embryogenesis in vitro from endosperm derived calli. A sequence of media formulations was used to induce and support proliferation of primary callus from endosperm, to induce embryogenesis from primary callus, and to allow embryo development leading to viable plantlets. Calli were induced from cellular endosperm of Citrus sinensis (sweet orange), C. Xparadisi

F. G. Gmitter; X. B. Ling; X. X. Deng

1990-01-01

294

Characterization of Constituents in the Peel of Citrus kawachiensis (Kawachibankan).  

PubMed

Fifteen constituents, including a new compound, were isolated from an ethanolic extract of the peel of Citrus kawachiensis Hort. ex. Y. Tanaka (Japanese brand name, kawachibankan) which is one of the citrus products specific to Ehime, Japan. The new compound was characterized as 4'-dihydrophaseic acid ?-glucopyranose ester (15) on the basis of spectral and chemical evidence. PMID:24018684

Amakura, Yoshiaki; Yoshimura, Morio; Ouchi, Kazusa; Okuyama, Satoshi; Furukawa, Yoshiko; Yoshida, Takashi

2013-09-07

295

Growth inhibitory effect of peel extract from Citrus junos  

Microsoft Academic Search

Extract from yuzu fruit peel (Citrus junos Sieb. ex Tanaka) strongly suppressed the germination of lettuce seeds while that from the peel of other citrus fruits such as navel orange (C. sinensis) and lemon (C. limon Burm. f.) had very little or no effect. The highest inhibitory activity was located in the peel followed by the segment but no significant

Shinsuke Fujihara; Tokurou Shimizu

2003-01-01

296

AN ASSESSMENT OF METHODS TO CLEAN CITRUS FRUIT SURFACES  

Technology Transfer Automated Retrieval System (TEKTRAN)

A move away from harsh chemicals towards more natural or organic postharvest treatments for citrus has prompted interest in alternate sanitizers for cleaning citrus in packinghouses. In this study we compare the efficiency of sanitizing methods on oranges. The oranges were collected from the field...

297

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

298

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

299

Inhibition of Spoiling Yeasts of Fruit Juices through Citrus Extracts.  

PubMed

This article reports on the bioactivities of citrus extracts (citrus extract, lemon extract, and neroli) toward Saccharomyces cerevisiae, Zygosaccharomyces bailii, Zygosaccharomyces rouxii, Pichia membranifaciens, and Rhodotorula bacarum. The bioactivities of the extracts (from 10 to 100 ppm) were evaluated through a microdilution method; thereafter, citrus extracts (0 to 80 ppm) were tested in combination with either pH (3.0 to 5.0) or temperature (5 to 25°C). Finally, a confirmatory experiment was run in a commercial drink (referred to as red fruit juice) containing citrus extract (40 ppm) that was inoculated with either S. cerevisiae or Z. bailii (5 log CFU/ml) and stored at 4 and 25°C. Yeasts increased to 7 log CFU/ml (Z. bailii) or 8 log CFU/ml (S. cerevisiae) in the control at 25°C, but the citrus extract addition controlled yeast growth for at least 3 days; under refrigeration, the effect was significant for 10 days. PMID:24112576

Bevilacqua, Antonio; Speranza, Barbara; Campaniello, Daniela; Corbo, Maria Rosaria; Sinigaglia, Milena

2013-10-01

300

[Isolation and identification of Metarhizium from Citrus grandis 'tomentosa' GAP base].  

PubMed

A type of entomopathogenic fungus of soil in Citrus grandis 'tomentosa' production base was isolated and identified with morphological and molecular biological methods, including pathogenesis, spore characteristic and ITS sequence analysis were conducted. The results showed that eighteen entomopathogenic fungi strains were isolated from the Tenebrio molitor infected in the soil samples, which were identified as Metarhizium anisopliae var. anisopliae. Based on results above, we concluded that there was quantity of Metarhizium resources in this area. These provided the useful information for controlling some pests of C. grandis by using these strains of fungus. PMID:22792782

Ma, Weisi; Xu, Jiang; Qiao, Haili; Chen, Jun; Li, Xiangming; Qin, Rongmin; Cheng, Huizhen

2012-04-01

301

Genetically engineered rice resistant to rice stripe virus, an insect-transmitted virus.  

PubMed Central

The coat protein (CP) gene of rice stripe virus was introduced into two japonica varieties of rice by electroporation of protoplasts. The resultant transgenic plants expressed the CP at high levels (up to 0.5% of total soluble protein) and exhibited a significant level of resistance to virus infection. Plants derived from selfed progeny of the primary transformants also expressed the CP and showed viral resistance, indicating stable transmission of the CP gene and the trait of resistance to the next generation. Moreover, the virally encoded strip disease-specific protein was not detected in transgenic plants expressing CP 8 weeks after inoculation, indicating protection before viral multiplication. These studies demonstrated that CP-mediated resistance to virus infection can be extended to cereals and to the viruses transmitted by an insect vector (planthopper). Images

Hayakawa, T; Zhu, Y; Itoh, K; Kimura, Y; Izawa, T; Shimamoto, K; Toriyama, S

1992-01-01

302

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) ...

303

THE APPLICATION OF EPIDEMIOLOGICAL ANALYSES OF CITRUS CANKER FOR THE DESIGN OF CITRUS CANKER ERADICATION PROCEDURES IN FLORIDA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Despite eradication efforts in both Florida and Brazil, citrus canker has been dispersed by a combination of storms and human movement. Citrus canker certainly causes crop losses put perhaps its most devastating effect is the social and political conflicts over mandated eradication programs. Epide...

304

Essential Oils from Citrus latifolia and Citrus reticulata Reduce Anxiety and Prolong Ether Sleeping Time in Mice  

Microsoft Academic Search

Essential oils (EO) from Citrus reticulata and Citrus latifolia were submitted to classical experimental procedures, such as light-dark box and marble-burying tests with male Swiss mice, to evaluate anxiolytic activity. Sedative activity was also investigated with EO from C. aurantium using the sleeping time induced by ether inhalation. EOs were administered 30 min before the experiments in doses ranging from

André Costa Gargano

2008-01-01

305

Antennal response of the Asian citrus psyllid to citrus volatiles and their degradation product  

Technology Transfer Automated Retrieval System (TEKTRAN)

Asian citrus psyllid antennae reacted strongly when stimulated with citral and ocimene stimulus tubes that had been aged for 3-5 days. When 20 µl of neat ocimene or citral were aged on filter paper strips in sealed Pasteur pipette stimulus tubes for 6 days on the laboratory bench, voltage changes we...

306

Cultivar identification of ‘Yuzu’ ( Citrus junos Sieb. ex Tanaka) and related acid citrus by leaf isozymes  

Microsoft Academic Search

Leaf extracts of 27 ‘Yuzu’ and related acid citrus cultivars were analyzed using polyacrylamide gel electrophoresis for isozyme variation of glutamate oxaloacetate transaminase (GOT) and shikimate dehydrogenase (SDH). SDH yielded 12 different isozyme phenotypes and six cultivars were discriminated by this enzyme alone. GOT produced 10 different isozyme phenotypes and four cultivars were separated. When both enzyme systems were taken

Mohammad Mizanur Rahman; Nobumasa Nito; Shiro Isshiki

2001-01-01

307

DEVELOPMENT AND CHARACTERIZATION OF RICE MUTANTS ALTERED IN THE RICE BLAST RESISTANT GENE PI-TA-MEDIATED DISEASE RESISTANCE PATHWAY  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Pi-ta gene in rice prevents the infection of the fungal pathogen Magnaporthe oryzae races containing the corresponding avirulence gene AVR-Pita. The Pi-ta gene encodes a putative cytoplasmic protein with a centrally localized nucleotide binding site and a leucine rich domain. AVR-Pita is a met...

308

Antibacterial activity of Citrus reticulata peel extracts.  

PubMed

Citrus peels were successively extracted with hexane, chloroform and acetone using a soxhlet extractor. The hexane and chloroform extracts were fractionated into alcohol-soluble and alcohol-insoluble fractions. These fractions were tested against different gram positive and gram negative bacteria. The EtOH-soluble fraction was found to be most effective. Fractionation of EtOH-soluble fraction on silica gel column yielded three polymethoxylated flavones, namely desmethylnobiletin, nobiletin and tangeretin. Their structures were confirmed by UV, 1H, 13C NMR and mass spectral studies. The findings indicated a potential of these natural compounds as biopreservatives in food applications. PMID:11204182

Jayaprakasha, G K; Negi, P S; Sikder, S; Rao, L J; Sakariah, K K

309

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

310

The evolution of CMA bands in Citrus and related genera.  

PubMed

Most species of Citrus and related genera display a similar karyotype with 2n = 18 and a variable number of terminal heterochromatic blocks positively stained with chromomycin A(3) (CMA(+) bands). Some of these blocks are 45S rDNA sites, whereas others may correspond to the main GC-rich satellite DNA found in several Citrus species. In the present work, the distribution of the 45S rDNA and the main satellite DNA isolated from C. sinensis (CsSat) were investigated by in situ hybridization in seven species of Citrus, two species of closely related genera (Fortunella obovata and Poncirus trifoliata) and four species of the subfamily Aurantioideae, which were less related to Citrus (Atalantia monophylla, Murraya paniculata, Severinia buxifolia, and Triphasia trifolia). In Citrus, Fortunella, and Poncirus, most CMA(+) bands colocalized only with CsSat sites, whereas others colocalized only with rDNA sites. However, some of these species displayed a few CMA(+) bands that colocalized with sites of both probes and other CMA(+) bands that did not colocalized with any of the probes. On the other hand, in the four species less related to Citrus, no CsSat signal was found on chromosomes. On Southern blot, the CsSat probe hybridized with genomic DNA from Citrus, Fortunella, and Poncirus at high stringency only, while under the less stringent conditions, it also hybridized with distantly related species. Therefore, CsSat sequences are the principal component of the heterochromatic blocks of Citrus, Poncirus, and Fortunella, whereas CsSat-like sequences seem to be widespread in the subfamily Aurantioideae. These data further suggest that the variable number of terminal CMA(+) bands observed on chromosomes of Citrus and related genera are probably the consequence of amplification or reduction in the number of CsSat-like sequences distributed on chromosome termini, paralleled by mutation and homogenization events, as proposed by the library hypothesis. PMID:20490650

e Silva, Ana Emília Barros; Marques, André; dos Santos, Karla G B; Guerra, Marcelo

2010-05-21

311

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

312

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

313

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

314

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

315

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...

316

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 ...

317

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

318

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 ...

319

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

320

EFFECT OF CHEMICALS, NITROGEN, TIME OF SOWING AND PANICLE BROWN SPOT EPIDEMICS ON RICE GRAIN DISCOLOURATION IN ITALY  

Microsoft Academic Search

SUMMARY Rice grain discolouration has a complex etiology and cannot be diagnosed prior to harvest. In Italy, the disease was thought to be associated with fungal infections, how- ever several studies contradicted this hypothesis. We re- port the distribution of grain discolouration, the most sus- ceptible Italian rice varieties, and the effects of epidemics of brown spot, induced by Cochliobolus

C. Pizzatti; P. Cortesi

321

A new excised-leaf assay method to test the inoculativity of the Asian citrus psyllid with Candidatus Liberibacter asiaticus associated with citrus huanglongbing disease  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Asian citrus psyllid (ACP, Diaphorina citri, Hemiptera: Psyllidae) is the primary vector of Candidatus Liberibacter asiaticus (Las) associated with huanglongbing, or citrus greening, the most devastating citrus disease worldwide. Here, we developed a new excised-leaf assay that can speed up Las...

322

Polymerase chain reaction detection of greening bacterium (Candidatus Liberibacter asiaticus) and Citrus mosaic virus in citrus tissues, by means of a simplified template-preparation protocol  

Microsoft Academic Search

Application of a simplified protocol for nucleic acid preparation for polymerase chain reaction (PCR) detection of greening bacterium (Candidatus Liberibacter asiaticus; Cla) and Citrus mosaic virus (CMBV) associated with citrus is described. Crude extracts of citrus tissues in NaOH - ethylenediaminetetraacetic acid solution, prepared without the use of liquid nitrogen, were spotted on a nitrocellulose membrane (NCM) and then eluted

V. K. Baranwal; K. N. Gupta; R. P. Singh

2007-01-01

323

Quantitative trait loci analysis of citrus leprosis resistance in an interspecific backcross family of ( Citrus reticulata Blanco ×  C. sinensis L. Osbeck) ×  C. sinensis L. Osb  

Microsoft Academic Search

Leprosis, caused by citrus leprosis virus (CiLV) and transmitted by the tenuipalpid mite Brevipalpus phoenicis, is one of the most important viruses of citrus in the Americas. Sweet oranges (Citrus sinensis L. Osb.) are highly susceptible to CiLV, while mandarins (C. reticulata Blanco) and some of their hybrids have higher tolerance or resistance to this disease. The mechanisms involved in

Marinês Bastianel; Mariângela Cristofani-Yaly; Antonio Carlos de Oliveira; Juliana Freitas-Astúa; Antonio Augusto Franco Garcia; Marcos Deon Vilela de Resende; Vandeclei Rodrigues; Marcos Antônio Machado

2009-01-01

324

[Historical and pharmalogical study of Citrus hassaku.].  

PubMed

The original plant of Citrus hassaku Hort. Tanaka was found at the Jyoudo Temple in Inno-shima, Hiroshima Prefecture, Japan by Ekei Shounin in the Edo Era. Citrus hassaku has been called "jagada" when it was first discovered. Since this fruit was seasoned for eating around "hassaku" (August 1st of the lunar calendar), it was given the scientific name as "C. hassaku." Today, the fresh raw fruits of C. Hassaku are cultivated as a seasonal food, and the most famous producing district of C. hassaku fruit is Wakayama Prefecture, representing about 60% of the Japanese output. The immature fruits of C. hassaku and its three main flavanone glycosides (naringin, neohesperidin and narirutin) was found to shown inhibitory activities on a compound 48/80 induced histamine released from mast cells, and anti-allergic effects on dinitrofluorobenzen (DNFB)-induced triphasic skin reactions in mice. The contents of the three flavanone glycosides in the immature fruits were higher than those in mature fruits. The application of extracts from the immature fruits of C. hassaku to skin care for patients with atopitic dermatitis has resulted in improving effects for 76% of the patients. Similar efficacy was obtained for patients pollinosis. PMID:16217907

Kubo, Minchinori; Matsuda, Hideaki; Tomohiro, Norimichi; Harima, Shouichi

2005-01-01

325

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

326

Nucleotide sequence of a hop stunt viroid variant isolated from citrus growing in Taiwan.  

PubMed

The 303 nucleotide sequence of HSVd-citrus(T), a hop stunt viroid (HSVd) variant present in Etrog citron growing in Taiwan, was determined from cDNAs amplified by the polymerase chain reaction. HSVd-citrus(T) is very similar to several HSVd isolates previously recovered from citrus or cucumber, and exhibits microsequence heterogeneity at positions 154 and 181. Phylogenetic analysis using maximum parsimony grouped HSVd-citrus(T) with seven other isolates from citrus and cucumber in a large cluster of "citrus-type" isolates. A similar analysis revealed marked differences in both the extent and distribution of sequence variation among naturally occurring isolates of potato spindle tuber viroid. PMID:7732666

Hsu, Y H; Chen, W; Owens, R A

1995-01-01

327

Induction of serotonin accumulation by feeding of rice striped stem borer in rice leaves.  

PubMed

Tryptophan (Trp)-related secondary metabolism has been implicated in the defense against pathogen infection and insect feeding in various gramineous species. Recently, we also reported that rice plant accumulated serotonin and tryptamine as well as their amide compounds coupled with phenolic acids in response to the infection by fungal pathogen. These compounds were likely to play an important role in the formation of physical barrier to the invading pathogens. To extend our study to elucidate the defensive role of Trp-derived secondary metabolism in gramineous plants, we examined in this study whether it is activated in response to herbivore attack as well. Third leaves of rice plant were fed on by third instar larvae of rice striped stem borer for 24 h or 48 h. The analysis of four Trp-derived metabolites including tryptamine, serotonin feruloyltryptamine (FerTry) and p-coumaroylserotonin (CouSer) by liquid chromatography coupled with tandem mass spectrometry revealed that their contents clearly increased in response to the larvae feeding. The respective amounts of tryptamine, serotonin, FerTry and CouSer in the larvae-fed leaves were 12-, 3.5-, 33- and 140-fold larger than those in control leaves 48 h after the start of feeding. PMID:19704837

Ishihara, Atsushi; Hashimoto, Yumi; Miyagawa, Hisashi; Wakasa, Kyo

2008-09-01

328

Induction of serotonin accumulation by feeding of rice striped stem borer in rice leaves  

PubMed Central

Tryptophan (Trp)-related secondary metabolism has been implicated in the defense against pathogen infection and insect feeding in various gramineous species. Recently, we also reported that rice plant accumulated serotonin and tryptamine as well as their amide compounds coupled with phenolic acids in response to the infection by fungal pathogen. These compounds were likely to play an important role in the formation of physical barrier to the invading pathogens. To extend our study to elucidate the defensive role of Trp-derived secondary metabolism in gramineous plants, we examined in this study whether it is activated in response to herbivore attack as well. Third leaves of rice plant were fed on by third instar larvae of rice striped stem borer for 24 h or 48 h. The analysis of four Trp-derived metabolites including tryptamine, serotonin feruloyltryptamine (FerTry) and p-coumaroylserotonin (CouSer) by liquid chromatography coupled with tandem mass spectrometry revealed that their contents clearly increased in response to the larvae feeding. The respective amounts of tryptamine, serotonin, FerTry and CouSer in the larvae-fed leaves were 12-, 3.5-, 33- and 140-fold larger than those in control leaves 48 h after the start of feeding.

Ishihara, Atsushi; Hashimoto, Yumi; Wakasa, Kyo

2008-01-01

329

Rhizobium-initiated rice growth inhibition caused by nitric oxide accumulation.  

PubMed

Isolates of Rhizobium leguminosarum bv. trifolii (the clover root-nodule endosymbiont) from the Nile River delta have been found to infect rice roots and colonize the intercellular spaces of the rice roots. Some of these isolates inhibit rice seedling growth but one in particular, R4, has been found in rice roots which develop and grow normally. We present evidence that the induced growth inhibition is due to a toxic accumulation of nitric oxide (NO), from the reduction of nitrate, and suggest that the reason that R4 does not inhibit rice root growth is because it is capable of completing the reduction of NO through to nitrogen gas. Thus, strain R4 is a candidate for engineering into a future biological nitrogen fixation system within these roots. PMID:17378431

Perrine-Walker, Francine M; Gartner, Elena; Hocart, Charles H; Becker, Anke; Rolfe, Barry G

2007-03-01

330

Waste Citrus Activated Sludge as a Poultry Feed Ingredient.  

National Technical Information Service (NTIS)

The report presents an evaluation of the potential of using waste activated sludge as a poultry feed supplement. The sludge used in this study was obtained from an activated sludge process treating concentrated citrus waste containing no sanitary wastewat...

R. H. Jones J. T. White B. L. Damron

1975-01-01

331

9. VIEW SHOWING ARIZONA CANAL WITH CITRUS ORCHARDS, FACING NORTH. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. VIEW SHOWING ARIZONA CANAL WITH CITRUS ORCHARDS, FACING NORTH. CAMELBACK MOUNTAIN IS IN THE BACKGROUND Photographer: unknown. No date - Arizona Canal, North of Salt River, Phoenix, Maricopa County, AZ

332

Citrus residues isolates improve astaxanthin production by Xanthophyllomyces dendrorhous.  

PubMed

The wild strain and two astaxanthin-overproducing mutant strains, W618 and GNG274, of Xanthophyllomyces dendrorhous were analyzed in order to assess their ability to grow and synthesize astaxanthin in a minimal medium containing (per liter): 2 g KH2PO4, 0.5 g MgSO4, 2 g KNO3, and 1 g yeast extract, and supplemented with citrus residues isolates as a carbon source (citrus medium). The selected strain W618 was evaluated under various contents of citrus juice. At the content of 20% (v/v), the highest astaxanthin production reached 22.63 mg L(-1), which was two-fold more than that observed in yeast malt medium. Addition of 8% (v/v) n-hexadecane to the citrus medium was found to be optimal, increasing the astaxanthin yield by 21.7%. PMID:21138061

Wu, Wei; Lu, Mingbo; Yu, Longjiang

333

FDA Technical Scientific Workshop On How Citrus Juice Firms ...  

Center for Food Safety and Applied Nutrition (CFSAN)

... RELEVANT AT THIS TIME TO STRESS THAT CITRUS ... T BUY IT FROM THE FIELD, IS THAT ... help accessing information in different file formats, see ... More results from www.fda.gov/food/guidanceregulation/haccp

334

Worker Reentry in Florida Citrus Pesticides in the Agricultural Environment.  

National Technical Information Service (NTIS)

The environmental behavior of five organophospate insecticides in Florida citrus are reported. Parathion disappearance rate from fruit, leaf, and soil surfaces was the same. Potential worker exposure to parathion was leaf surface, soil surface, fruit surf...

H. N. Nigg

1980-01-01

335

Novel approaches for postharvest preservation of fresh citrus fruits  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus are nonclimacteric fruits that are harvested when their commercial maturity index has already been reached. The maturity index expresses the relationship between two important internal quality parameters, solid soluble concentration and titratable acidity, that determine the fruit consumer ac...

336

Comparative anaylsis of Asian citrus psyllid and potato psyllid antennae  

Technology Transfer Automated Retrieval System (TEKTRAN)

The comparative investigation of the morphological basis for olfactory reception in the Asian citrus psyllid (Diaphorina citri) and the potato/tomato psyllid (Bactericera cockerelli (Hemiptera: Psyllidae) was performed using scanning electron microscopy to elucidate the antennal sensory arrays being...

337

Molecular and structural evolution of Citrus satellite DNA  

Microsoft Academic Search

Highly repeated satellite DNA (stDNA) of citric plants was characterized by cloning and sequencing 10–14 repeats of each plant\\u000a (Citrus limon, C. sinensis, C. ichangensis, Poncirus trifoliata). The monomers are mostly 181 bp in length with a GC-content between 60% and 68% (significantly higher than the average GC-content\\u000a of the citrus group genomes). Similarity among the repeats indicates that they

J.-Y. Fann; A. Kovarik; V. Hemleben; N. I. Tsirekidze; T. G. Beridze

2001-01-01

338

The evolution of CMA bands in Citrus and related genera  

Microsoft Academic Search

Most species of Citrus and related genera display a similar karyotype with 2n?=?18 and a variable number of terminal heterochromatic blocks positively stained with chromomycin A3 (CMA+ bands). Some of these blocks are 45S rDNA sites, whereas others may correspond to the main GC-rich satellite DNA found in\\u000a several Citrus species. In the present work, the distribution of the 45S

Ana Emília Barros e Silva; André Marques; Karla G. B. dos Santos; Marcelo Guerra

2010-01-01

339

Characterization and regulation of ammonium transport systems in Citrus plants  

Microsoft Academic Search

We have investigated both the kinetics and regulation of 15NH4+ influx in roots of 3-month-old hydroponically grown Citrus (Citrus sinensis L. Osbeck 2 Poncirus trifoliata Blanco) seedlings. The 15NH4+ influx is saturable below an external ammonium concentration of 1 mM, indicating the action of a high-affinity transport system (HATS). The HATS is under feedback repression by the N status of

M. Cerezo; P. Tillard; A. Gojon; E. Primo-Millo; P. García-Agustín

2001-01-01

340

Zinc Nutrition, a Global Concern for Sustainable Citrus Production  

Microsoft Academic Search

Sub-optimum nutrition of zinc is globally one of the prime concerns of targeting sustainability in citrus production. Metabolically, Zn-deficiency induces many morphological, cytological and anatomical changes that lead to low flowering intensity and fruit set in addition to affecting the quality of citrus produced on sustained basis. Global occurrence of Zn-deficiency known by various names like rosette, little leaf, frenching,

A. K. Srivastava; Shyam Singh

2005-01-01

341

Control of citrus green and blue molds by Chinese propolis  

Microsoft Academic Search

Green and blue molds, caused by Penicillium digitatum and Penicillium italicum, respectively, are economically important postharvest diseases of citrus fruits. In this study, Chinese propolis ethyl acetate\\u000a extract (PEAE) was evaluated to control P. digitatum and P. italicum on postharvest citrus fruits. The results indicated PEAE strongly inhibited mycelia growth and induced hyphae prominent abnormal\\u000a morphological alterations. Also, PEAE had

Shuzhen Yang; Litao Peng; Yunjiang Cheng; Feng Chen; Siyi Pan

2010-01-01

342

Does ethylene degreening affect internal quality of citrus fruit?  

Microsoft Academic Search

Citrus fruit are non-climacteric. However, exposure to exogenous ethylene, e.g., during ethylene degreening, stimulates various ripening-related processes in the peel tissue, such as destruction of the green chlorophyll pigments and accumulation of orange\\/yellow carotenoids. Nonetheless, it is not yet known whether exogenous ethylene affects internal ripening processes in citrus flesh. To address this question, we examined the possible effects of

Lina Mayuoni; Zipora Tietel; Bhimanagouda S. Patil; Ron Porat

2011-01-01

343

Lipolytic effects of citrus peel oils and their components.  

PubMed

This study was conducted to determine the lipolytic effects of eight kinds of citrus peel oils and their components. All of the citrus peel oils revealed lipolytic effects on olive oil model solution ranging from 10.9 to 73.8%. Hakyul (Citrus natsudaidai Hayata) showed the highest lipolytic effect (73.8%), followed by yuza (Citrus junos Sieb. ex Tanaka, 68.1%) and lemon (Citrus limonium, 63.4%), and their effects were comparable with or stronger than that of 5 mM raspberry ketone (p < 0.05). Among 17 authentic compounds relating to citrus peel oils, octanal (78.6%) showed the highest lipolytic effect, followed by gamma-terpinene (76.3%), limonene (75%), terpinen-4-ol (70.7%), nerol (69.9%), p-cymene (67.7%), and geranyl acetate (67.2%), and their effects were stronger than that of 5 mM raspberry ketone (p < 0.05). Ethyl acetate, alpha-pinene, myrcene, citronellal, linallyl acetate, and citronellol exhibited poor lipolytic effect in the model solution. Lipolytic effect was found to be high when the oils included a higher content of gamma-terpinene and p-cymene. Limonene showed potential lipolytic effect, and its effect is likely to be enhanced by the presence of gamma-terpinene and p-cymene. It is considered that monoterpene hydrocarbons consisting of one or two double bonds would have stronger lipolytic effect than those having three double bonds. PMID:16637681

Choi, Hyang-Sook

2006-05-01

344

Identification of QTLs associated with citrus resistance to Phytophthora gummosis.  

PubMed

Citrus gummosis, caused by Phytophthora spp., is an important citrus disease in Brazil. Almost all citrus rootstock varieties are susceptible to it to some degree, whereas resistance is present in Poncirus trifoliata, a closely related species. The objective of this study was to detect QTLs linked to citrus Phytophthora gummosis resistance. Eighty individuals of the F1 progeny, obtained by controlled crosses between Sunki mandarin Citrus sunki (susceptible) and Poncirus trifoliata cv. Rubidoux (resistant), were evaluated. Resistance to Phytophthora parasitica was evaluated by inoculating stems of young plants with a disc of fungal mycelia and measuring lesion lengths a month later. Two QTLs linked to gummosis resistance were detected in linkage groups 1 and 5 of the P. trifoliata map, and one QTL in linkage group 2 of the C. sunki map. The phenotypic variation explained by individual QTLs was 14% for C. sunki and ranged from 16 to 24% for P. trifoliata. The low character heritability (h2 = 18.7%) and the detection of more than one QTL associated with citrus Phytophthora gummosis resistance showed that inheritance of the resistance is quantitative. PMID:16424605

Siviero, Amauri; Cristofani, Mariangela; Furtado, Edson L; Garcia, Antonio A F; Coelho, Alexandre S G; Machado, Marcos A

2006-01-01

345

Incidence of fruit flies on coffee and citrus and quarantine treatment of citrus fruits by gamma radiation.  

National Technical Information Service (NTIS)

The objective of this study was to evaluate the fruit fly infestation on coffee and citrus, and also to determine gamma radiation doses for immature stages of Ceratitis capitata and Anastrepha fraterculus, in order to satisfy quarantine regulations. Coffe...

A. Raga

1996-01-01

346

Citrus tristeza virus p23: a unique protein mediating key virus-host interactions.  

PubMed

The large RNA genome of Citrus tristeza virus (CTV; ca. 20 kb) contains 12 open reading frames, with the 3'-terminal one corresponding to a protein of 209 amino acids (p23) that is expressed from an abundant subgenomic RNA. p23, an RNA-binding protein with a putative zinc-finger domain and some basic motifs, is unique to CTV because no homologs have been found in other closteroviruses, including the type species of the genus Beet yellows virus (despite both viruses having many homologous genes). Consequently, p23 might have evolved for the specific interaction of CTV with its citrus hosts. From a functional perspective p23 has been involved in many roles: (i) regulation of the asymmetrical accumulation of CTV RNA strands, (ii) induction of the seedling yellows syndrome in sour orange and grapefruit, (iii) intracellular suppression of RNA silencing, (iv) elicitation of CTV-like symptoms when expressed ectopically as a transgene in several Citrus spp., and (v) enhancement of systemic infection (and virus accumulation) in sour orange and CTV release from the phloem in p23-expressing transgenic sweet and sour orange. Moreover, transformation of Mexican lime with intron-hairpin constructs designed for the co-inactivation of p23 and the two other CTV silencing suppressors results in complete resistance against the homologous virus. From a cellular point of view, recent data indicate that p23 accumulates preferentially in the nucleolus, being the first closterovirus protein with such a subcellular localization, as well as in plasmodesmata. These major accumulation sites most likely determine some of the functional roles of p23. PMID:23653624

Flores, Ricardo; Ruiz-Ruiz, Susana; Soler, Nuria; Sánchez-Navarro, Jesús; Fagoaga, Carmen; López, Carmelo; Navarro, Luis; Moreno, Pedro; Peña, Leandro

2013-05-03

347

Citrus tristeza virus p23: a unique protein mediating key virus-host interactions  

PubMed Central

The large RNA genome of Citrus tristeza virus (CTV; ca. 20 kb) contains 12 open reading frames, with the 3?-terminal one corresponding to a protein of 209 amino acids (p23) that is expressed from an abundant subgenomic RNA. p23, an RNA-binding protein with a putative zinc-finger domain and some basic motifs, is unique to CTV because no homologs have been found in other closteroviruses, including the type species of the genus Beet yellows virus (despite both viruses having many homologous genes). Consequently, p23 might have evolved for the specific interaction of CTV with its citrus hosts. From a functional perspective p23 has been involved in many roles: (i) regulation of the asymmetrical accumulation of CTV RNA strands, (ii) induction of the seedling yellows syndrome in sour orange and grapefruit, (iii) intracellular suppression of RNA silencing, (iv) elicitation of CTV-like symptoms when expressed ectopically as a transgene in several Citrus spp., and (v) enhancement of systemic infection (and virus accumulation) in sour orange and CTV release from the phloem in p23-expressing transgenic sweet and sour orange. Moreover, transformation of Mexican lime with intron-hairpin constructs designed for the co-inactivation of p23 and the two other CTV silencing suppressors results in complete resistance against the homologous virus. From a cellular point of view, recent data indicate that p23 accumulates preferentially in the nucleolus, being the first closterovirus protein with such a subcellular localization, as well as in plasmodesmata. These major accumulation sites most likely determine some of the functional roles of p23.

Flores, Ricardo; Ruiz-Ruiz, Susana; Soler, Nuria; Sanchez-Navarro, Jesus; Fagoaga, Carmen; Lopez, Carmelo; Navarro, Luis; Moreno, Pedro; Pena, Leandro

2013-01-01

348

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

349

Naringin Levels in Citrus Tissues 1  

PubMed Central

The preparation of a tritiated radiotracer that was used in the radioimmunoassay of naringin (naringenin-7-O-?-rhamnosyl- (1-2)-?-d-glucopyranoside) and which was synthesized by reduction of the carbonyl group of the flavanone is reported. The resulting assay has a detection limit of 0.5 picomole per 0.1 milliliter, is specific for the 7-neohesperidoside substitution on flavanones, and can measure naringin in crude extracts of plant tissues. This radioimmunoassay is compared with three other naringin immunoassays which use antibodies raised against two different haptens and different tracers labeled with 125I or 3H. The applicability of the methods to the quantification of naringin and other flavanone neohesperidosides in citrus tissue is discussed.

Jourdan, Pablo S.; Weiler, Elmar W.; Mansell, Richard L.

1985-01-01

350

Inhibition of oral carcinogenesis by citrus flavonoids.  

PubMed

Six citrus flavonoids were tested for antineoplastic activity. The hamster cheek pouch model was utilized, and the solutions of the flavonoids (2.0-2.5%) and the solution of the carcinogen, 7,12-dimethylbenz[a]anthracene (0.5%), were applied topically to the pouches. The pouches of the positive controls were treated with the solvent used to dissolve the flavonoids and the solution of the carcinogen. The data show that 4 flavonoids (hesperetin, neohesperidin, tangeretin, and nobiletin) were inactive. The results with naringin and naringenin show that both of these flavonoids significantly lowered tumor number [5.00 (control group), 2.53 (naringin group), and 3.25 (naringenin group)]. Naringin also significantly reduced tumor burden [269 mm(3)(control group) and 77.1 mm(3)(naringin group)]. The data suggest that naringin and naringenin, 2 flavonoids found in high concentrations in grapefruit, may be able to inhibit the development of cancer. PMID:18444138

Miller, Edward G; Peacock, Jason J; Bourland, T Campbell; Taylor, Samuel E; Wright, John M; Patil, Bhimanagouda S; Miller, Edward G

2008-01-01

351

Naringin Levels in Citrus Tissues 1  

PubMed Central

The quantitative distribution of the flavanone-7-neohesperidoside, naringin, in seeds, seedlings, young plants, branches, flowers, and fruit of Citrus paradisi Macfad., cv `Duncan' was analyzed by radioimmunoassay. High levels of naringin were associated with very young tissue and lower levels were found in older tissues. Seed coats of ungerminated seeds and young shoots had high naringin concentrations whereas cotyledons and roots had very low concentrations. Light-grown seedlings contained nearly twice as much naringin as etiolated seedlings and, in young plants and branches, the naringin content was highest in developing leaves and stem tissue. In flowers, the ovary had the highest levels of naringin, accounting for nearly 11% of the fresh weight. There was a net increase in the total naringin content of fruits during growth. However, due to the large increase in fruit size, there was a concomitant decrease in the naringin concentration as the fruit matured.

Jourdan, Pablo S.; McIntosh, Cecilia A.; Mansell, Richard L.

1985-01-01

352

Citrus bergamia juice: phytochemical and technological studies.  

PubMed

Fresh juice from bergamot (Citrus bergamia Risso) has been studied to evaluate the polyphenolic composition by HPLC-DAD analysis and total polyphenols content by UV method. The main constituent, Naringin, has been selected as analytical and biological marker of the juice. Juice has been loaded onto maltodextrin matrix by spray-drying. The produced maltodextrin/juice powder (BMP) showed neither significant change in total polyphenols content nor decrease in antioxidant properties with respect to fresh juice. Moreover, BMP displayed high in vitro dissolution rate of the bioactive constituents in water and in simulated biological fluids. BMP appears as promising functional raw material for food, nutraceutical and pharmaceutical products. With this aim, a formulation study to develop tablets (BMT) for oral administration has been also performed. The produced solid oral dosage form preserved high polyphenols content, showed complete disaggregation in few minutes and satisfying dissolution rate of the bioactive constituents in simulated biological fluids. PMID:21834231

Picerno, Patrizia; Sansone, Francesca; Mencherini, Teresa; Prota, Lucia; Aquino, Rita Patrizia; Rastrelli, Luca; Lauro, Maria Rosaria

2011-07-01

353

China, Peoples Republic of: Citrus. Annual, 2008. GAIN Report Number CH8110.  

National Technical Information Service (NTIS)

Chinas MY 2008 citrus production is forecast at 21 MMT, up 10 percent from the revised MY 2007 figure, the result of favorable weather conditions throughout the major citrus producing areas during the crop development period. Orange production is forecast...

C. Beckman S. Peavey W. Bugang W. Tong

2008-01-01

354

Energy Conservation in Citrus Processing. Technical Progress Report, October 1, 1979-March 31, 1980.  

National Technical Information Service (NTIS)

The Sunkist Citrus Plant in Ontario, California, processes about 6 million pounds of citrus fruit per day to make products which include frozen concentrated juice; chilled, pasteurized, natural strength juice; molasses from peel; dried meal from peel; pec...

1980-01-01

355

HYPOLIPIDEMIC EFFECT AND ABSORPTION OF CITRUS POLYMETHOXYLATED FLAVONES IN HAMSTERS WITH DIET-INDUCED HYPERCHOLESTEROLEMIA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Formulations containing citrus polymethoxylated flavones (PMFs), mainly tangeretin, or citrus flavanone glucosides, hesperidin and naringin, were evaluated for cholesterol-lowering potential in hamsters with diet-induced hypercholesterolemia. PMF metabolites were also investigated. Diets containin...

356

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

357

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

358

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

359

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

360

Involvement of rooting factors and free IAA in the rootability of citrus species stem cuttings  

Microsoft Academic Search

Sagee, O., Raviv, M., Medina, Sh., Becker, D. and Cosse, A., 1992. Involvement of rooting factors and free IAA in the rootability of citrus species stem cuttings. Scientia Hortic., 51: 187-195. Two-year-old trees of cultivar 'Rangpur' lime (Citrus fimonia Osb. ) and of cultivar 'Oroblanco', a triploid pummelo-grapefruit hybrid (Citrus grandis Osb. X Citrus paradisi Macf.), which had not reached

O. Sagee; M. Raviv; D. Beckeff; A. Cosse

1992-01-01

361

Effects of climate, natural enemies and biocides on three citrus mites in coastal New South Wales  

Microsoft Academic Search

Infestations of the citrus rust mitePhyllocoptruta oleivora (Ashmead), the brown citrus rust miteTegolophus australis Keifer, and the citrus red mitePanonychus citri (McGregor), did not cause economic damage to orange (Citrus sinensis (L.) Osbeck) in two coastal New South Wales orchards during a three-year study. The seasonal abundance of the mites and their phytoseiid and coccinellid predators was defined using periodic

G. A. C. Beattie; E. A. Roberts; C. L. Vanhoff; L. K. Flack

1991-01-01

362

Somatic hybridization in citrus: An effective tool to facilitate variety improvement  

Microsoft Academic Search

Summary  Citrus somatic hybridization and cybridization via protoplast fusion has become an integral part of citrus variety improvement programs worldwide. Citrus somatic hybrid plants\\u000a have been regenerated from more than 200 parental combinations, and several cybrid combinations have also been produced. Applications\\u000a of somatic hybridization to citrus scion improvement include the production of quality tetraploid breeding parents that can\\u000a be used

J. W. Grosser; P. Ollitrault; O. Olivares-Fuster

2000-01-01

363

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

364

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

365

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

366

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

367

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

368

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

369

Citrus essential oils and four enantiomeric pinenes against Culex pipiens (Diptera: Culicidae)  

Microsoft Academic Search

The aim of this study was to evaluate the toxicity of pinenes (entantiomers of ?- and ?-) and essential oils from Greek plants of the Rutaceae family against the mosquito larvae of Culex pipiens (Diptera: Culicidae). Essential oils were isolated by hydrodistillation from fruit peel of orange (Citrus sinensis L.), lemon (Citrus limon L.), and bitter orange (Citrus aurantium L.).

Antonios Michaelakis; Dimitrios Papachristos; Athanasios Kimbaris; George Koliopoulos; Athanasios Giatropoulos; Moschos G. Polissiou

2009-01-01

370

Digestibility by Dairy Cows of Monosaccharide Constituents in Total Mixed Rations Containing Citrus Pulp  

Microsoft Academic Search

Ten lactating cows were divided into two groups and individually fed ad libitum one of two experimental total mixed rations (TMR) as follows: 1) a TMR con- taining 20% corn grain and 10% dry citrus pulp (high corn); and 2) a TMR containing 21% citrus pulp and 9% corn grain (high citrus pulp). Both TMR also con- tained corn silage

J. Miron; E. Yosef; D. Ben-Ghedalia; L. E. Chase; D. E. Bauman; R. Solomon

2002-01-01

371

Seasonal flight activity by the Asian citrus psyllid in east central Florida  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is an important invasive citrus pest in the United States because it vectors a bacterium responsible for a devastating disease of citrus known as huanglongbing. Information was lacking on seasonal aspects of flight activit...

372

7 CFR 457.106 - Texas citrus tree crop insurance provisions.  

Code of Federal Regulations, 2010 CFR

...2009-01-01 2009-01-01 false Texas citrus tree crop insurance provisions. 457.106 Section...INSURANCE REGULATIONS § 457.106 Texas citrus tree crop insurance provisions. The Texas Citrus Tree Crop Insurance Provisions for the 1999...

2009-01-01

373

7 CFR 457.106 - Texas citrus tree crop insurance provisions.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Texas citrus tree crop insurance provisions. 457.106 Section...INSURANCE REGULATIONS § 457.106 Texas citrus tree crop insurance provisions. The Texas Citrus Tree Crop Insurance Provisions for the 1999...

2010-01-01

374

Regeneration and molecular characterization of intergeneric somatic hybrids between Citrus reticulata and Poncirus trifoliata  

Microsoft Academic Search

Citrus exocortis viroid (CEV) is widespread in citrus production areas where trifoliate orange [Poncirus trifoliata (L.) Raf.] is used as rootstock. Citrus reticulata Blanco cv. Red tangerine, a different rootstock, is tolerant to CEV. Embryogenic protoplasts of C. reticulata cv. Red tangerine were electrically fused with mesophyll protoplasts from P. trifoliata, and five embryoids were regenerated after 40 days of

W. W. Guo; Y. J. Cheng; X. X. Deng

2002-01-01

375

7 CFR 457.107 - Florida citrus fruit crop insurance provisions.  

Code of Federal Regulations, 2013 CFR

...or could be marketed as fresh citrus fruit; (5) Was harvested...freeze; (b) Not including citrus fruit that: (1) Was missing...detached living portion of a plant joined to a stock in grafting. Top worked. A buckhorned citrus tree with a new scion...

2013-01-01

376

Some physiological and morphological characteristics of citrus plants for drought resistance  

Microsoft Academic Search

Tolerance and avoidance mechanisms to drought stress were studied in 6-month-old plants of Newhall orange (Citrus sinensis (L.) Osbeck) and Ellendale tangor (orange × mandarin hybrid) (Citrus sinensis (L) Osbeck × Citrus reticulata Blanco) during a drought\\/rewatering cycle under controlled conditions. Drought stress did not promote osmotic adjustment, while elastic adjustment (tissue elasticity increase) was noted in stressed orange and

Robert Savé; Carme Biel; Rafael Domingo; M. Carmen Ruiz-Sánchez; Arturo Torrecillas

1995-01-01

377

Transcriptome Analysis of Early Fruit Development in Three Seedy Citrus Genotypes and Their Seedless Mutants  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seedlessness is desirable for most citrus fruit, and identification of spontaneous or irradiated seedless mutants is important in developing citrus cultivars. We conducted a transcriptome analysis in early fruit development of three seedy citrus types (‘Fallglo’, a largely C. reticulata hybrid; ‘Pi...

378

Enhancement of cold tolerance and inhibition of lipid peroxidation by citrus dehydrin in transgenic tobacco  

Microsoft Academic Search

Citrus (Citrus unshiu Marcov.) dehydrin in response to chilling stress was overexpressed in tobacco (Nicotiana tabacum L.), and the cold stress tolerance of transgenics at low temperature was analyzed. The freezing at ?4 °C for 3 h of 24 independent lines indicated that a phenotype expressing citrus dehydrin showed less electrolyte leakage than the control. Dehydrin protein content was correlated with freezing

Masakazu Hara; Shogo Terashima; Tomoko Fukaya; Toru Kuboi

2003-01-01

379

Movement of Simazine in Runoff Water from Citrus Orchard Row Middles as Affected by Mechanical Incorporation  

Microsoft Academic Search

In California, pre-emergence herbicide residues have been measured in runoff water from citrus orchards that resulted from winter rainfall. This study measured the effect of rainfall on the redistribution of herbicides within a citrus orchard and the effect that shallow mechanical incorporation had on residue movement. Simulated rainfall treatments were applied to plots within a citrus orchard where simazine was

J. Troiano; C. Garretson

1998-01-01

380

78 FR 58992 - Notice of Request for Extension of Approval of an Information Collection; Citrus Canker...  

Federal Register 2010, 2011, 2012, 2013

...from quarantined areas to prevent the spread of citrus canker. DATES: We will consider...suppress, control, prevent, or retard the spread of plant pests, such as citrus canker...regulations to prevent the interstate spread of citrus canker are contained...

2013-09-25

381

Descriptions of new varieties recently distributed from the Citrus Clonal Protection Program  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Citrus Clonal Protection Program (CCPP) is operated through the Department of Plant Pathology and Microbiology at University of California (UC) Riverside and is funded in large part by The California Citrus Research Board (CRB). The CCPP processes citrus propagative material in two phases. First...

382

76 FR 17617 - Changes to Treatments for Citrus Fruit From Australia  

Federal Register 2010, 2011, 2012, 2013

...Changes to Treatments for Citrus Fruit From Australia AGENCY: Animal and Plant Health Inspection...species of citrus fruit imported from Australia into the United States. These new treatments...species of citrus fruit imported from Australia into the United States. We also...

2011-03-30

383

Wind speed and wind-associated leaf injury affect severity of citrus canker on Swingle citrumelo  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus canker (caused by the bacterial pathogen Xanthomonas citri subsp. citri, Xcc) can cause severe damage to citrus. It is endemic in Florida, and occurs in other citrus growing regions. The bacterium is dispersed predominantly in rain splash. To simulate dispersal in splash, and to investigate t...

384

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

385

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

386

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...

387

Genetic diversity of citrus bacterial canker pathogens preserved in herbarium specimens  

PubMed Central

Citrus bacterial canker (CBC) caused by Xanthomonas axonopodis pv. citri (Xac) was first documented in India and Java in the mid 19th century. Since that time, the known distribution of the disease has steadily increased. Concurrent with the dispersion of the pathogen, the diversity of described strains continues to increase, with novel strains appearing in Saudi Arabia, Iran, and Florida in the last decade. Herbarium specimens of infected plants provide an historical record documenting both the geographic distribution and genetic diversity of the pathogen in the past. However, no method was available to assess the genetic diversity within these herbarium samples. We have developed a method, insertion event scanning (IES), and applied the method to characterize the diversity present within CBC populations documented as herbarium specimens over the past century. IES is based on the specific amplification of junction fragments that define insertion events. The potential for IES in current forensic applications is demonstrated by finding an exact match of pathogen genotypes preserved in herbarium specimens from Japan and Florida, demonstrating the source of the original outbreak of citrus canker in Florida in 1911. IES is a very sensitive technique for differentiating bacterial strains and can be applied to any of the several hundred bacteria for which full genomic sequence data are available.

Li, Wenbin; Song, Qijian; Brlansky, Ronald H.; Hartung, John S.

2007-01-01

388

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

389

Colonization of citrus seed coats by 'Candidatus Liberibacter asiaticus': implications for seed transmission of the bacterium.  

PubMed

Huanglongbing is an economically damaging disease of citrus associated with infection by 'Candidatus Liberibacter asiaticus'. Transmission of the organism via infection of seeds has not been demonstrated but is a concern since some citrus varieties, particularly those used as rootstocks in commercial plantings are propagated from seed. We compared the incidence of detection of 'Ca. Liberibacter asiaticus' DNA in individual fruit peduncles, seed coats, seeds, and in germinated seedlings from 'Sanguenelli' sweet orange and 'Conners' grapefruit fruits sampled from infected trees. Using real-time quantitative PCR (qPCR) we detected pathogen DNA in nucleic acid extracts of 36 and 100% of peduncles from 'Sanguenelli' and from 'Conners' fruits, respectively. We also detected pathogen DNA in extracts of 37 and 98% of seed coats and in 1.6 and 4% of extracts from the corresponding seeds of 'Sanguenelli' and 'Conners', respectively. Small amounts of pathogen DNA were detected in 10% of 'Sanguenelli' seedlings grown in the greenhouse, but in none of 204 extracts from 'Conners' seedlings. Pathogen DNA was detected in 4.9% and in 89% of seed coats peeled from seeds of 'Sanguenelli' and 'Conners' which were germinated on agar, and in 5% of 'Sanguenelli' but in none of 164 'Conners' seedlings which grew from these seeds on agar. No pathogen DNA was detected in 'Ridge Pineapple' tissue at 3 months post-grafting onto 'Sanguenelli' seedlings, even when pathogen DNA had been detected initially in the 'Sanguenelli' seedling. Though the apparent colonization of 'Conners' seeds was more extensive and nearly uniform compared with 'Sanguenelli' seeds, no pathogen DNA was detected in 'Conners' seedlings grown from these seeds. For either variety, no association was established between the presence of pathogen DNA in fruit peduncles and seed coats and in seedlings. PMID:21714779

Hilf, Mark E

2011-10-01

390

Rapid and sensitive detection of Citrus Bacterial Canker by loop-mediated isothermal amplification combined with simple visual evaluation methods  

Microsoft Academic Search

BACKGROUND: Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type

Luciano A Rigano; María R Marano; Atilio P Castagnaro; Alexandre Morais Do Amaral; Adrian A Vojnov

2010-01-01

391

7 CFR 301.76-4 - Labeling requirements for regulated nursery stock produced within an area quarantined for citrus...  

Code of Federal Regulations, 2013 CFR

...area quarantined for citrus greening. 301.76-4...Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE...QUARANTINE NOTICES Citrus Greening and Asian Citrus...the person offering the plants for commercial sale are...planting in a commercial citrus grove within that...

2013-01-01

392

Interaction of Simulated Acid Rain with Ozone on Freeze Resistance, Growth, and Mineral Nutrition in Citrus and Avocado 1  

Microsoft Academic Search

The combined effects of O3 and acid rain on freeze resistance, growth, and mineral nutrition were studied using broadleaf-evergreen citrus and avocado trees. Using a factorial design, 'Ruby red' grapefruit (Citrus paradisi L.) trees on either Volkamer lemon (Citrus volkameriana Ten. & Pasq.) or sour orange (Citrus aurantium L.) rootstocks and 'Pancho' avocado trees (Persea americana Mill.) on 'Waldin' rootstock

David M. Eissenstat; James P. Syvertsen; Thomas J. Dean; Jon D. Johnson; George Yelenosky

1991-01-01

393

Diurnal patterns in flight activity and effects of light on host finding behavior of the Asian citrus psyllid  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Asian citrus psyllid (ACP), Diaphorina citri (Hemiptera: Psyllidae), is an invasive pest of citrus in the United States. The psyllid feeds and reproduces primarily on new flush growth of citrus and other rutaceous plants. Because it vectors the bacterial causal agents of the deadly citrus green...

394

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

395

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

396

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

397

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

398

The Freeze Risk to Florida Citrus. Part 1: Investment Decisions.  

NASA Astrophysics Data System (ADS)

In the 1980s Florida was struck by an unusual series of severe freezes that caused enormous damage to citrus groves. While citrus acreage in relatively freeze-free parts of the state has expanded rapidly since these freezes, serious questions remain about the commercial viability of growing citrus crops in some central Florida counties. This paper considers the role that freeze risk plays in the investment decisions of citrus growers. A simplified example is used to estimate tolerable levels of freeze risk for individuals evaluating the investment at different discount rates, and to show the impact of changes in the risk level. Changes in estimated freeze risk in the 1980s are computed over the historical temperature record, and related to the growers' replanting decisions. It is concluded that the computed changes in the probability of a killing freeze would be sufficient to alter the citrus planting decisions of some investors. Furthermore, the longest available climate record should be used to estimate the risk of such low-probability extreme events.

Miller, Kathleen A.; Downton, Mary W.

1993-02-01

399

Simultaneous detection and differentiation of Rice black streaked dwarf virus (RBSDV) and Southern rice black streaked dwarf virus (SRBSDV) by duplex real time RT-PCR  

PubMed Central

Background The diseases caused by Rice black streaked dwarf virus (RBSDV) and Southern rice black streaked dwarf virus (SRBSDV) have been occurring epidemically in China and southeastern Asia in recent years. A sensitive, reliable and quantitative method is required to detect and distinguish for RBSDV and SRBSDV in rice and vector insects. Results We developed a sensitive and lineage-specific duplex real time RT-qPCR for detection of RBSDV and SRBSDV in a single or/and double infection in rice samples. The duplex RT-qPCR was optimized using standard samples transcribed by T7 Large Scale RNA Production System in vitro. We developed a reliable system for duplex RT-qPCR, in which its co-efficiency of RBSDV and SRBSDV, were 91.6% and 90.7%, respectively. The coefficient of determination was more than 0.990; the slope of linear equation was ?3.542, and ?3.567, respectively. Out of 30 samples collected in North and Central China, which were suspected to be infected with these two viruses, 10 samples were detected RBSDV positive by RT-PCR and 12 samples by RT-qPCR. No mixed infections were found. Simultaneously, out of total 60 samples collected from Southern China, which were also suspected to be infected with these two viruses, 41 samples were determined SRBSDV positive by RT-PCR and 47 samples by RT-qPCR. Also in this case no mixed infections were found. The rice genes eEF-1a and UBQ5 were selected as internal controls for quantification assay also performed as good expression stability. Conclusion The duplex RT-qPCR assay provided as a sufficiently sensitive, specific, accurate, reproducible and rapid tool for the detection and differentiation of RBSDV and SRBSDV. The RT-qPCR assay can be used in routine diagnostic of these two viruses in order to study the disease epidemiology in rice crops.

2013-01-01

400

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.

401

Citrus MAF1, a repressor of RNA polymerase III, binds the Xanthomonas citri canker elicitor PthA4 and suppresses citrus canker development.  

PubMed

Transcription activator-like (TAL) effectors from Xanthomonas species pathogens act as transcription factors in plant cells; however, how TAL effectors activate host transcription is unknown. We found previously that TAL effectors of the citrus canker pathogen Xanthomonas citri, known as PthAs, bind the carboxyl-terminal domain of the sweet orange (Citrus sinensis) RNA polymerase II (Pol II) and inhibit the activity of CsCYP, a cyclophilin associated with the carboxyl-terminal domain of the citrus RNA Pol II that functions as a negative regulator of cell growth. Here, we show that PthA4 specifically interacted with the sweet orange MAF1 (CsMAF1) protein, an RNA polymerase III (Pol III) repressor that controls ribosome biogenesis and cell growth in yeast (Saccharomyces cerevisiae) and human. CsMAF1 bound the human RNA Pol III and rescued the yeast maf1 mutant by repressing tRNA(His) transcription. The expression of PthA4 in the maf1 mutant slightly restored tRNA(His) synthesis, indicating that PthA4 counteracts CsMAF1 activity. In addition, we show that sweet orange RNA interference plants with reduced CsMAF1 levels displayed a dramatic increase in tRNA transcription and a marked phenotype of cell proliferation during canker formation. Conversely, CsMAF1 overexpression was detrimental to seedling growth, inhibited tRNA synthesis, and attenuated canker development. Furthermore, we found that PthA4 is required to elicit cankers in sweet orange leaves and that depletion of CsMAF1 in X. citri-infected tissues correlates with the development of hyperplastic lesions and the presence of PthA4. Considering that CsMAF1 and CsCYP function as canker suppressors in sweet orange, our data indicate that TAL effectors from X. citri target negative regulators of RNA Pol II and Pol III to coordinately increase the transcription of host genes involved in ribosome biogenesis and cell proliferation. PMID:23898043

Soprano, Adriana Santos; Abe, Valeria Yukari; Smetana, Juliana Helena Costa; Benedetti, Celso Eduardo

2013-07-29

402

Telomere-Targeted Retrotransposons in the Rice Blast Fungus Magnaporthe oryzae: Agents of Telomere Instability  

PubMed Central

The fungus Magnaporthe oryzae is a serious pathogen of rice and other grasses. Telomeric restriction fragments in Magnaporthe isolates that infect perennial ryegrass (prg) are hotspots for genomic rearrangement and undergo frequent, spontaneous alterations during fungal culture. The telomeres of rice-infecting isolates are very stable by comparison. Sequencing of chromosome ends from a number of prg-infecting isolates revealed two related non-LTR retrotransposons (M. oryzae Telomeric Retrotransposons or MoTeRs) inserted in the telomere repeats. This contrasts with rice pathogen telomeres that are uninterrupted by other sequences. Genetic evidence indicates that the MoTeR elements are responsible for the observed instability. MoTeRs represent a new family of telomere-targeted transposons whose members are found exclusively in fungi.

Starnes, John H.; Thornbury, David W.; Novikova, Olga S.; Rehmeyer, Cathryn J.; Farman, Mark L.

2012-01-01

403

Induced resistance against the Asian citrus psyllid, Diaphorina citri, by ?-aminobutyric acid in citrus.  

PubMed

?-Aminobutyric acid (BABA) is known to induce resistance to microbial pathogens, nematodes and insects in several host plant/pest systems. The present study was undertaken to determine whether a similar effect of BABA occurred against the Asian citrus psyllid, Diaphorina citri Kuwayama, in citrus. A 25 mM drench application of BABA significantly reduced the number of eggs/plant as compared with a water control, whereas 200 and 100 mM applications of BABA reduced the numbers of nymphs/plant and adults/plants, respectively. A 5 mM foliar application of BABA significantly reduced the number of adults but not eggs or nymphs when compared with a water control treatment. In addition, leaf-dip bioassays using various concentrations (25–500 mM) of BABA indicated no direct toxic effect on 2nd and 5th instar nymphs or adult D. citri. BABA-treated plants were characterized by significantly lower levels of iron, magnesium, phosphorus, sodium, sulfur and zinc as compared with control plants. The expression level of the PR-2 gene (?-1,3-glucanase) in BABA-treated plants that were also damaged by D. citri adult feeding was significantly higher than in plants exposed to BABA, D. citri feeding alone or control plants. Our results indicate the potential for using BABA as a systemic acquired resistance management tool for D. citri. PMID:23590847

Tiwari, Siddharth; Meyer, Wendy L; Stelinski, Lukasz L

2013-04-16

404

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...

405

Analysis of genetic and molecular identity among field isolates of the rice blast fungus with an international differential system, rep-PCR and DNA sequencing  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Pi-ta gene deployed in the Southern US rice germplasm is effective in preventing the infection by strains of Magnaporthe oryzae isolates that carry the avirulence gene AVR-Pita1. In the present study, a total of 169 isolates from rice (Oryza sativa) cultivars, with and without Pi-ta, were analyz...

406

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

407

Dissipation, residues, and risk assessment of spirodiclofen in citrus.  

PubMed

The dissipation, residues, and distribution of spirodiclofen, a new type of insecticide and acaricide that belongs to the class of ketoenols or tetronic acids, in citrus were investigated in this study. Risk assessment of sprodiclofen was also conducted based on those data. The open-field experiments were conducted in Guangdong, Fujian, and Guangxi of China. Results showed that the half-lives in citrus ranged from 6.5 to 13.6 days at three sites. The terminal residues of spirodiclofen were all below the FAO/WHO maximum residue limit of 0.5 mg/kg in citrus, when they were determined 14 days after final application. Distribution of spirodiclofen in peel and flesh was analyzed, and residues were found to be concentrated on peel. Risk assessment was performed by calculation of risk quotient, which showed that the use of spirodiclofen is comparably safe for humans. PMID:23880916

Sun, Haibin; Liu, Congyun; Wang, Siwei; Liu, Yanping; Liu, Mingjin

2013-07-24

408

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

409

Weedy hosts and prevalence of potential leafhopper vectors (Hemiptera: Cicadellidae) of a phytoplasma (16SrIX group) associated with Huanglongbing symptoms in citrus groves.  

PubMed

Huanglongbing (HLB) is a severe citrus (Citrus spp.) disease associated with the bacteria genus Candidatus Liberibacter, detected in Brazil in 2004. Another bacterium was found in association with HLB symptoms and characterized as a phytoplasma belonging to the 16SrIX group. The objectives of this study were to identify potential leafhopper vectors of the HLB-associated phytoplasma and their host plants. Leafhoppers were sampled every other week for 12 mo with sticky yellow cards placed at two heights (0.3 and 1.5 m) in the citrus tree canopy and by using a sweep net in the ground vegetation of two sweet orange, Citrus sinensis (L.) Osbeck, groves infected by the HLB-phytoplasma in São Paulo state. Faunistic analyses indicated one Agalliinae (Agallia albidula Uhler) and three Deltocephalinae [Balclutha hebe (Kirkaldy), Planicephalus flavicosta (Stål), and Scaphytopius (Convelinus) marginelineatus (Stål)] species, as the most abundant and frequent leafhoppers (Hemiptera: Cicadellidae). Visual observations indicated an association of leafhopper species with some weeds and the influence of weed species composition on leafhopper abundance in low-lying vegetation. S. marginelineatus and P. flavicosta were more frequent on Sida rhombifolia L. and Althernantera tenella Colla, respectively, whereas A. albidula was observed more often on Conyza bonariensis (L.) Cronq. and B. hebe only occurred on grasses. DNA samples of field-collected S. marginelineatus were positive by polymerase chain reaction and sequencing tests for the presence of the HLB-phytoplasma group, indicating it as a potential vector. The association of leafhoppers with their hosts may be used in deciding which management strategies to adopt against weeds and diseases in citrus orchards. PMID:22606800

Marques, R N; Teixeira, D C; Yamamoto, P T; Lopes, J R S

2012-04-01

410

Sampling Citrus Fibrous Roots and Tylenchulus semipenetrans.  

PubMed

Sampling precision was investigated for Tylenchulus semipenetrans juveniles and males in soil and females from roots and for citrus fibrous root mass density. For the case of two composite samples of 15 cores each, counts of juvenile and male nematodes were estimated to be within 40% of mu, at P < 0.06 (alpha) in orchards where x > 1,500 nematodes/100 cm(3) soil. A similar level of alpha was estimated for measurements of fibrous root mass density, but at a precision level of 25% of mu. Densities of female nematodes were estimated with less precision than juveniles and males. Precision estimates from a general sample plan derived from Taylor's Power Law were in good agreement with estimates from individual orchards. Two aspects involved in deriving sampling plans for management advisory purposes were investigated. A minimum of five to six preliminary samples were required to appreciably reduce bias toward underestimation of sigma. The use of a Student's t value rather than a standard normal deviate in formulae to estimate sample size increased the estimates by an average of three units. Cases in which the use of z rather than Student's t is appropriate for these formulae are discussed. PMID:19279914

Duncan, L W; El-Morshedy, M M; McSorley, R

1994-12-01

411

Sampling Citrus Fibrous Roots and Tylenchulus semipenetrans  

PubMed Central

Sampling precision was investigated for Tylenchulus semipenetrans juveniles and males in soil and females from roots and for citrus fibrous root mass density. For the case of two composite samples of 15 cores each, counts of juvenile and male nematodes were estimated to be within 40% of ?, at P < 0.06 (?) in orchards where x? > 1,500 nematodes/100 cm³ soil. A similar level of ? was estimated for measurements of fibrous root mass density, but at a precision level of 25% of ?. Densities of female nematodes were estimated with less precision than juveniles and males. Precision estimates from a general sample plan derived from Taylor's Power Law were in good agreement with estimates from individual orchards. Two aspects involved in deriving sampling plans for management advisory purposes were investigated. A minimum of five to six preliminary samples were required to appreciably reduce bias toward underestimation of ?. The use of a Student's t value rather than a standard normal deviate in formulae to estimate sample size increased the estimates by an average of three units. Cases in which the use of z rather than Student's t is appropriate for these formulae are discussed.

Duncan, L. W.; El-Morshedy, M. M.; McSorley, R.

1994-01-01

412

RACK1 functions in rice innate immunity by interacting with the Rac1 immune complex.  

PubMed

A small GTPase, Rac1, plays a key role in rice (Oryza sativa) innate immunity as part of a complex of regulatory proteins. Here, we used affinity column chromatography to identify rice RACK1 (for Receptor for Activated C-Kinase 1) as an interactor with Rac1. RACK1 functions in various mammalian signaling pathways and is involved in hormone signaling and development in plants. Rice contains two RACK1 genes, RACK1A and RACK1B, and the RACK1A protein interacts with the GTP form of Rac1. Rac1 positively regulates RACK1A at both the transcriptional and posttranscriptional levels. RACK1A transcription was also induced by a fungal elicitor and by abscisic acid, jasmonate, and auxin. Analysis of transgenic rice plants and cell cultures indicates that RACK1A plays a role in the production of reactive oxygen species (ROS) and in resistance against rice blast infection. Overexpression of RACK1A enhances ROS production in rice seedlings. RACK1A was shown to interact with the N terminus of NADPH oxidase, RAR1, and SGT1, key regulators of plant disease resistance. These results suggest that RACK1A functions in rice innate immunity by interacting with multiple proteins in the Rac1 immune complex. PMID:18723578

Nakashima, Ayako; Chen, Letian; Thao, Nguyen Phuong; Fujiwara, Masayuki; Wong, Hann Ling; Kuwano, Masayoshi; Umemura, Kenji; Shirasu, Ken; Kawasaki, Tsutomu; Shimamoto, Ko

2008-08-22

413

Reproducible RNA Preparation from Sugarcane and Citrus for Functional Genomic Applications  

PubMed Central

High-throughput functional genomic procedures depend on the quality of the RNA used. Copurifying molecules can negatively impact the functionality of some plant RNA preparations employed in these procedures. We present a simplified, rapid, and scalable SDS/phenol-based method that provides the high-quantity and -quality RNA required by the newly emerging biotechnology applications. The method is applied to isolating RNA from tissues of two biotechnologically important crop plants, sugarcane and citrus, which provide a challenge due to the presence of fiber, polysaccharides, or secondary metabolites. The RNA isolated by this method is suitable for several downstream applications including northern blot hybridization, microarray analysis, and quantitative RT-PCR. This method has been used in a diverse range of projects ranging from screening plant lines overexpressing mammalian genes to analyzing plant responses to viral infection and defense signaling molecules.

Damaj, Mona B.; Beremand, Phillip D.; Buenrostro-Nava, Marco T.; Riedel, Beth; Molina, Joe J.; Kumpatla, Siva P.; Thomas, Terry L.; Mirkov, T. Erik

2009-01-01

414

Energy conservation in citrus processing. Final project report  

SciTech Connect

Alternative energy conserving systems for use in citrus processing plants were synthesized and evaluated in terms of energy savings and economic return. The energy intensive operations that are carried out in citrus processing plants include conveying and extraction, concentration, peel drying, refrigeration, and pasteurization. The alternative energy conserving systems are synthesized from components and subsystems that are arranged to make use of energy cascading and thermodynamic regeneration to reduce the overall energy usage. System requirements such as air pollution rules and plant processing load cycles, a characterization of major operations, description of alternative system concepts, and the evaluation of alternative systems in terms of economic parameters and energy usage are identified.

Leo, M.A.; Lari, R.I.; Moore, N.R.; Broussard, M.R.; Gyamfi, M.

1981-11-01

415

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

416

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

417

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

418

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

419

Enhanced resistance to blast fungus and bacterial blight in transgenic rice constitutively expressing OsSBP, a rice homologue of mammalian selenium-binding proteins.  

PubMed

The rice Oryza sativa selenium-binding protein homologue (OsSBP) gene encodes a homologue of mammalian selenium-binding proteins, and it has been isolated as one of the genes induced by treating a plant with a cerebroside elicitor from rice blast fungus. The possible role of OsSBP in plant defense was evaluated by using a transgenic approach. Plants overexpressing OsSBP showed enhanced resistance to a virulent strain of rice blast fungus as well as to rice bacterial blight. The expression of defense-related genes and the accumulation of phytoalexin after infection by rice blast fungus were accelerated in the OsSBP overexpressors. A higher level of H(2)O(2) accumulation and reduced activity of such scavenging enzymes as ascorbate peroxidase and catalase were seen when the OsSBP-overexpressing plants were treated with the protein phosphatase 1 inhibitor, calyculin A. These results suggest that the upregulation of OsSBP expression conferred enhanced tolerance to different pathogens, possibly by increasing plant sensitivity to endogenous defense responses. Additionally, the OsSBP protein might have a role in modulating the defense mechanism to biotic stress in rice. PMID:15118317

Sawada, Kazutoshi; Hasegawa, Morifumi; Tokuda, Lena; Kameyama, Junko; Kodama, Osamu; Kohchi, Takayuki; Yoshida, Kazuya; Shinmyo, Atsuhiko

2004-04-01

420

A population of variants of a viroid closely related to citrus viroid-I in citrus plants  

Microsoft Academic Search

Summary.  ?Sequencing analyses showed a population of variants consisting of 325–330 nucleotides (nt) of a viroid closely related to\\u000a citrus viroid (CVd)-I in citrus plants. These variants, for which we propose the tentative acronym CVd-I-LSS (low sequence\\u000a similarity), have only 82–85% sequence similarities to CVd-I variants. A phylogenetic tree showed that the CVd-I-LSS variants\\u000a formed an individual cluster that was distinct

Takao Ito; Hiroyuki Ieki; Katsumi Ozaki

2000-01-01

421

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

422

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.

423

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

424

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

425

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

426

Epigenetic Inheritance in Rice Plants  

PubMed Central

Background and Aims Epigenetics is defined as mechanisms that regulate gene expression without base sequence alteration. One molecular basis is considered to be DNA cytosine methylation, which reversibly modifies DNA or chromatin structures. Although its correlation with epigenetic inheritance over generations has been circumstantially shown, evidence at the gene level has been limited. The present study aims to find genes whose methylation status directly correlates with inheritance of phenotypic changes. Methods DNA methylation in vivo was artificially reduced by treating rice (Oryza sativa ssp. japonica) seeds with 5-azadeoxycytidine, and the progeny were cultivated in the field for > 10 years. Genomic regions with changed methylation status were screened by the methylation-sensitive amplified polymorphysm (MSAP) method, and cytosine methylation was directly scanned by the bisulfite mapping method. Pathogen infection with Xanthomonas oryzae pv. oryzae, race PR2 was performed by the scissors-dip method on mature leaf blades. Key Results The majority of seedlings were lethal, but some survived to maturity. One line designated as Line-2 showed a clear marker phenotype of dwarfism, which was stably inherited by the progeny over nine generations. MSAP screening identified six fragments, among which two were further characterized by DNA blot hybridization and direct methylation mapping. One clone encoding a retrotransposon gag–pol polyprotein showed a complete erasure of 5-methylcytosines in Line-2, but neither translocation nor expression of this region was detectable. The other clone encoded an Xa21-like protein, Xa21G. In wild-type plants, all cytosines were methylated within the promoter region, whereas in Line-2, corresponding methylation was completely erased throughout generations. Expression of Xa21G was not detectable in wild type but was constitutive in Line-2. When infected with X. oryzae pv. oryzae, against which Xa21 confers resistance in a gene-for-gene manner, the progeny of Line-2 were apparently resistant while the wild type was highly susceptible without Xa21G expression. Conclusions These results indicated that demethylation was selective in Line-2, and that promoter demethylation abolished the constitutive silencing of Xa21G due to hypermethylation, resulting in acquisition of disease resistance. Both hypomethylation and resistant trait were stably inherited. This is a clear example of epigenetic inheritance, and supports the idea of Lamarckian inheritance which suggested acquired traits to be heritable.

Akimoto, Keiko; Katakami, Hatsue; Kim, Hyun-Jung; Ogawa, Emiko; Sano, Cecile M.; Wada, Yuko; Sano, Hiroshi

2007-01-01

427

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

428

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

429

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

430

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

431

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...

432

Low Energy Technology. A Unit of Instruction in Citrus Production.  

ERIC Educational Resources Information Center

|This unit of instruction on citrus production was designed for use by agribusiness and natural resources teachers in Florida high schools and by agricultural extension agents as they work with adults and students. It is one of a series of 11 instructional units (see note) written to help teachers and agents to educate their students and clients…

Olson, Jeanne A.; Becker, William J.

433

Developments in ethanol production from citrus peel waste  

Technology Transfer Automated Retrieval System (TEKTRAN)

Each year, the Florida citrus juice industry produces about 3.5~5.0 million tons of wet peel waste, which are currently dried and sold as cattle feed, often at a loss, to dispose of the waste residual. Profitability would be greatly improved if the peel waste could be used to produce higher value pr...

434

Asian citrus psyllid genome (Diaphorina citri, Hemiptera)-Update 2013  

Technology Transfer Automated Retrieval System (TEKTRAN)

The psyllid genome is a scientific breakthrough that opens the psyllid genetic blueprint to investigations of all questions ranging from taxonomic origins to the understanding of developmental biology, to the acquisition and transmission of pathogens. The Asian citrus psyllid, Diaphorina citri (Hemi...

435

Comparison of some biochemical characteristics of different citrus fruits  

Microsoft Academic Search

The goal of this investigation was to evaluate the antioxidant properties of some citrus fruits. The contents of dietary fibre, total polyphenols, essential phenolics, ascorbic acid and some trace elements of lemons, oranges and grapefruits were determined and compared with their total radical-trapping antioxidative potential (TRAP). There were no significant differences in the contents of total, soluble and insoluble dietary

Shela Gorinstein; Olga Mart??n-Belloso; Yong-Seo Park; Ratiporn Haruenkit; Antonin Lojek; Milan ???ž; Abraham Caspi; Imanuel Libman; Simon Trakhtenberg

2001-01-01

436

Cytological and molecular characterization of three gametoclones of citrus clementina  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three gametoclonal plants of Citrus clementina Hort. ex Tan., cv. Nules, designated ESP, FRA, and ITA (derived from three labs in Spain, France, and Italy, respectively), were selected for cytological and molecular characterization in order to elucidate genomic rearrangements provoked by haploidizat...

437

Flavanones in Citrus fruit: Structure–antioxidant activity relationships  

Microsoft Academic Search

Epidemiological surveys have shown an inverse relationship between the intake of fruit and the incidence of coronary heart disease and some type of cancer. Data found in the literature regarding the flavonoids in general while this study focuses on flavanones, a subclass of flavonoids which occurs in Citrus fruit. The aim of this work is to elucidate the antioxidant or

Danila Di Majo; Marco Giammanco; Maurizio La Guardia; Elisa Tripoli; Santo Giammanco; Enrico Finotti

2005-01-01

438

Emergence and Phylodynamics of Citrus tristeza virus in Sicily, Italy  

PubMed Central

Citrus tristeza virus (CTV) outbreaks were detected in Sicily island, Italy for the first time in 2002. To gain insight into the evolutionary forces driving the emergence and phylogeography of these CTV populations, we determined and analyzed the nucleotide sequences of the p20 gene from 108 CTV isolates collected from 2002 to 2009. Bayesian phylogenetic analysis revealed that mild and severe CTV isolates belonging to five different clades (lineages) were introduced in Sicily in 2002. Phylogeographic analysis showed that four lineages co-circulated in the main citrus growing area located in Eastern Sicily. However, only one lineage (composed of mild isolates) spread to distant areas of Sicily and was detected after 2007. No correlation was found between genetic variation and citrus host, indicating that citrus cultivars did not exert differential selective pressures on the virus. The genetic variation of CTV was not structured according to geographical location or sampling time, likely due to the multiple introduction events and a complex migration pattern with intense co- and re-circulation of different lineages in the same area. The phylogenetic structure, statistical tests of neutrality and comparison of synonymous and nonsynonymous substitution rates suggest that weak negative selection and genetic drift following a rapid expansion may be the main causes of the CTV variability observed today in Sicily. Nonetheless, three adjacent amino acids at the p20 N-terminal region were found to be under positive selection, likely resulting from adaptation events.

Davino, Salvatore; Willemsen, Anouk; Panno, Stefano; Davino, Mario; Catara, Antonino; Elena, Santiago F.; Rubio, Luis

2013-01-01

439

Study of pulsed electric field treated citrus juices  

Microsoft Academic Search

The effect of pulsed electric field (PEF) treatment, applied in a continuous system, on physical and chemical properties of freshly squeezed citrus juices (grapefruit, lemon, orange, tangerine) was studied. The aim of the present work was to investigate the effect of PEF technology on pH, Brix°, electric conductivity, viscosity, nonenzymatic browning index (NEBI), hydroxymethylfurfurol (HMF), color, organic acid content, and

Zs. Cserhalmi; Á. Sass-Kiss; M. Tóth-Markus; N. Lechner

2006-01-01

440

HEALTHY PRODUCTS FROM CITRUS JUICE PROCESSING WASTE STREAMS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus waste streams contain significant amounts of simple sugars, flavonoids and dietary fiber as cellulose, hemicellulose, and pectin. A process has been developed to convert sugars and cellulose (after enzyme hydrolysis) into ethanol through fermentation for use as a biofuel. Pectin is hydrolyz...

441

Micellar electrokinetic capillary chromatography of limonoid glucosides from citrus seeds  

Microsoft Academic Search

This report presents the results of an investigation into the application of micellar electrokinetic capillary chromatography (MECC) for the analysis of limonoid glucosides in a citrus seed extract. MECC based on sodium dodecyl sulphate (SDS) was used to provide highly efficient separations of the closely related structures. A phosphate-borate buffer containing SDS was used to optimize the separation conditions for

Vinayagum E. Moodley; Dulcie A. Mulholland; Mark W. Raynor

1995-01-01

442

Chlorosis Produced by Fluorine on Citrus in Florida  

Microsoft Academic Search

A unique chlorotic leaf pattern on citrus trees in Florida that is attributed to fluorine is reported. The chlorosis was first noted in Polk County in April 1950 and was associated with a triple superphosphate manufacturing plant that recently opened. The polluting condition was corrected, but as new triple superphosphate plants opened, chlorosis increased. Florida pebble rock phosphate contains 2-4%

I. W. Wander; J. J. McBride Jr.

1956-01-01

443

Economic analysis of ethanol production from citrus peel waste  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Florida citrus juice industry produces about 3-4 million tons of wet peel waste per year. In current industrial practices, waste peels are dried and sold as cattle feed to offset the waste disposal cost. Profitability could be greatly improved if this amount of peel can be used to produce high...

444

Heat treatment of ‘Oroblanco’ citrus fruit to control insect infestation  

Microsoft Academic Search

‘Oroblanco’ citrus fruit were heat treated with hot forced air at holding temperatures from 43 to 47°C for times from 10 to 90min. Unwaxed fruit developed heat damage at 47°C, while waxed fruit showed heat damage at 44°C. Thermal death kinetics of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), eggs, first and third instars were tested in a hot water system

Susan Lurie; Tomislav Jemric; Asya Weksler; Ruti Akiva; Yoav Gazit

2004-01-01

445

Comparative genomic characterization of citrus-associated Xylella fastidiosa strains  

Microsoft Academic Search

BACKGROUND: The xylem-inhabiting bacterium Xylella fastidiosa (Xf) is the causal agent of Pierce's disease (PD) in vineyards and citrus variegated chlorosis (CVC) in orange trees. Both of these economically-devastating diseases are caused by distinct strains of this complex group of microorganisms, which has motivated researchers to conduct extensive genomic sequencing projects with Xf strains. This sequence information, along with other

Vivian S da Silva; Cláudio S Shida; Fabiana B Rodrigues; Diógenes CD Ribeiro; Alessandra A de Souza; Helvécio D Coletta-Filho; Marcos A Machado; Luiz R Nunes; Regina Costa de Oliveira

2007-01-01

446

Energy recovery by production of fuel from citrus wastes  

Microsoft Academic Search

A study to determine how much energy can be recovered from a Florida citrus processing plant was conducted. The production of ethyl alcohol in particular was examined as it is thought to represent the greatest potential for immediate energy recovery. Three-fourths of the energy expended to produce, harvest, process and market a box of fruit was recoverable using existing technology,

Wesley Clark

1982-01-01

447

Selection of a NaCl-tolerant Citrus plant  

Microsoft Academic Search

Summary  The objective of the work was to select Citrus plants more tolerant to elevated NaCl concentrations in the irrigation water. For this purpose, unfertilized Troyer citrange ovules treated with a chemical mutagenic agent (ethyl methane sulphonate) were cultured in vitro. Whole plants were regenerated from embryos developed in the nucellar tissue of the ovule. The screening for salt tolerance was

Pilar García-Agustín; Eduardo Primo-Millo

1995-01-01

448

MALLS/RI SETUP FOR SENSITIVE DETECTION OF CITRUS POLYSACCHARIDES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Properties of citrus polysaccharides such as pectin can be dependent on molecular weight (MW). For example, gel strength and solution properties of pectin are dependent on the MW, and extraction conditions for pectin can also affect MW. Thus, it is advantageous for optimizing extraction conditions...

449

GENETIC TOXICITY OF A STANDARDIZED MIXTURE OF CITRUS POLYMETHOXYLATED FLAVONES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Flavonoids are a ubiquitous family of phytochemicals that display a variety of biological effects both beneficial and adverse depending on the individual compound. In the present studies, the mutagenicity of a mixture of polymethoxylated flavones (PMFs) purified from citrus peel oil was evaluated. ...

450

UTILIZATION OF GC-GC IN CITRUS FLAVOR ANALYSIS  

Technology Transfer Automated Retrieval System (TEKTRAN)

This presentation presents some work on separating, identifying and cataloging chiral compounds in citrus and their approximate ranges in various products. A dual oven GC-GC-MS system with a cryo-trapping transfer line was used with a pre-column and chiral analytical column. Samples from Brazil, F...

451

Citrus stubborn disease incidence determined by quantitative real time PCR  

Technology Transfer Automated Retrieval System (TEKTRAN)

Quantitative real-time (q) PCR was developed for detection of Spiroplasma citri, the causal agent of citrus stubborn disease (CSD), using the DNA binding fluorophore SYBR Green I. The primer pair, P58-3f/4r, developed based on sequences from the P58 putative adhesin multigene of the pathogen result...

452

SPATIAL AND TEMPORAL ANALYSIS OF CITRUS SUDDEN DEATH IN BRAZIL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus Sudden Death (CSD) is a disease of unknown etiology that affects sweet orange grafted on Rangpur lime and Volkamerian lemon in Brazil. Ordinary runs analysis of CSD-symptomatic trees indicated a departure from randomness of symptomatic trees status among immediately adjacent trees mainly wit...

453

Injection and decontamination of citrus-canker-inoculated leaf surfaces  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus canker (Xanthomonas citri subsp. citri, Xcc) is now considered endemic in Florida and continues to spread. Personnel and equipment decontamination is practiced in both disease-endemic and disease-free areas to reduce the risk of bacterial spread by man or machinery. We used grapefruit leaf su...

454

Antioxidant activity of Citrus paradisi seeds glyceric extract  

Microsoft Academic Search

The antioxidant activity of Citrus paradisi (grapefruit) seeds glyceric extract dissolved in ethanol and in aqueous media was evaluated using three different methods: evaluation by DPPH assay, by 5-lipoxygenase assay and by luminol\\/xanthine\\/xanthine oxidase chemiluminescence assay. The total phenolic content was determined by the Prussian Blue method opportunely modified. The grapefruit seeds glyceric extract utilized as aqueous solutions demonstrated antioxidant

Laura Giamperi; Daniele Fraternale; Anahi Bucchini; Donata Ricci

2004-01-01

455

Subcritical Water Extraction of Nutraceutical Compounds from Citrus Pomaces  

Microsoft Academic Search

Subcritical water (SCW) extraction of citrus pomaces (CPs) was carried out, and antioxidant activity and nutraceutical compound levels of the SCW extracts were evaluated in detail. At first, CP samples were subjected to the SCW extraction under various conditions focusing on the extraction temperature and time. Consequently, the highest total phenol contents, radical scavenging activity, and reducing power were found

Jong-Wan Kim; Tatsuya Nagaoka; Yasuyuki Ishida; Tatsuya Hasegawa; Kuniyuki Kitagawa; Seung-Cheol Lee

2009-01-01

456

The draft genome of sweet orange (Citrus sinensis).  

PubMed

Oranges are an important nutritional source for human health and have immense economic value. Here we present a comprehensive analysis of the draft genome of sweet orange (Citrus sinensis). The assembled sequence covers 87.3% of the estimated orange genome, which is relatively compact, as 20% is composed of repetitive elements. We predicted 29,445 protein-coding genes, half of which are in the heterozygous state. With additional sequencing of two more citrus species and comparative analyses of seven citrus genomes, we present evidence to suggest that sweet orange originated from a backcross hybrid between pummelo and mandarin. Focused analysis on genes involved in vitamin C metabolism showed that GalUR, encoding the rate-limiting enzyme of the galacturonate pathway, is significantly upregulated in orange fruit, and the recent expansion of this gene family may provide a genomic basis. This draft genome represents a valuable resource for understanding and improving many important citrus traits in the future. PMID:23179022

Xu, Qiang; Chen, Ling-Ling; Ruan, Xiaoan; Chen, Dijun; Zhu, Andan; Chen, Chunli; Bertrand, Denis; Jiao, Wen-Biao; Hao, Bao-Hai; Lyon, Matthew P; Chen, Jiongjiong; Gao, Song; Xing, Feng; Lan, Hong; Chang, Ji-Wei; Ge, Xianhong; Lei, Yang; Hu, Qun; Miao, Yin; Wang, Lun; Xiao, Shixin; Biswas, Manosh Kumar; Zeng, Wenfang; Guo, Fei; Cao, Hongbo; Yang, Xiaoming; Xu, Xi-Wen; Cheng, Yun-Jiang; Xu, Juan; Liu, Ji-Hong; Luo, Oscar Junhong; Tang, Zhonghui; Guo, Wen-Wu; Kuang, Hanhui; Zhang, Hong-Yu; Roose, Mikeal L; Nagarajan, Niranjan; Deng, Xiu-Xin; Ruan, Yijun

2012-11-25

457

Citrus limon: a source of flavonoids of pharmaceutical interest  

Microsoft Academic Search

Some of the medicinal properties of lemons are due to the flavonoids they contain since they are involved in many biological activities and have many health-related functions. The levels of the principal flavanones and flavone found in different cultivars of Citrus limon, are analysed in an attempt to identify the most interesting as regards the content of such secondary compounds.

J. A. Del R??o; M. D. Fuster; P. Gómez; I. Porras; A. Garc??a-Lidón; A. Ortuño

2004-01-01

458

STRATEGIC APPROACH TOWARD INDUSTRIAL UTILIZATION OF CITRUS PEEL  

Technology Transfer Automated Retrieval System (TEKTRAN)

It is well known that washed citrus peel is composed mainly of polysaccharides. Maximum utilization of this material resides on finding new products derived from the cellulosics or pectins found in this source. Strategies on this conversion will be discussed. For ease of chemical and enzymatic mo...

459

21 CFR 74.302 - Citrus Red No. 2.  

Code of Federal Regulations, 2013 CFR

... 74.302 Section 74.302 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...ADDITIVES SUBJECT TO CERTIFICATION Foods § 74.302 Citrus Red No...more than 10 parts per million. Arsenic (as As), not more than 1...

2013-04-01

460

Reproductive biology and behavior of the Asian citrus psyllid  

Technology Transfer Automated Retrieval System (TEKTRAN)

A review of research conducted during 2006-2008 on the reproductive biology and behavior of the Asian citrus psyllid (Diaphorina citri) will be presented. Information to be discussed will include daily patterns of mating; frequency of mating; pre-mating and pre-oviposition intervals; daily and seaso...

461

Comparative Physical Examination of Various Citrus Peel Essential Oils  

Microsoft Academic Search

Physical parameters of various citrus peel essential oils were determined in this study. Essential oils from the peels of Kinnow (C. reticulata, var. mandarin), Fewtrell's early (C. reticulata, var. tangerine), Malta (C. sinensis var. malta), Mousami (C. sinensis var. mousami), grape fruit (C. paradisi) and eureka lemon (C. limon) were extracted by applying cold expressing method. Eureka lemon had the

MUHAMMAD MUSHTAQ AHMAD; FAQIR MUHAMMAD ANJUM; EHSAN ELAHI BAJWA

2006-01-01

462

Ascending migration of endophytic rhizobia, from roots to leaves, inside rice plants and assessment of benefits to rice growth physiology.  

PubMed

Rhizobia, the root-nodule endosymbionts of leguminous plants, also form natural endophytic associations with roots of important cereal plants. Despite its widespread occurrence, much remains unknown about colonization of cereals by rhizobia. We examined the infection, dissemination, and colonization of healthy rice plant tissues by four species of gfp-tagged rhizobia and their influence on the growth physiology of rice. The results indicated a dynamic infection process beginning with surface colonization of the rhizoplane (especially at lateral root emergence), followed by endophytic colonization within roots, and then ascending endophytic migration into the stem base, leaf sheath, and leaves where they developed high populations. In situ CMEIAS image analysis indicated local endophytic population densities reaching as high as 9 x 10(10) rhizobia per cm3 of infected host tissues, whereas plating experiments indicated rapid, transient or persistent growth depending on the rhizobial strain and rice tissue examined. Rice plants inoculated with certain test strains of gfp-tagged rhizobia produced significantly higher root and shoot biomass; increased their photosynthetic rate, stomatal conductance, transpiration velocity, water utilization efficiency, and flag leaf area (considered to possess the highest photosynthetic activity); and accumulated higher levels of indoleacetic acid and gibberellin growth-regulating phytohormones. Considered collectively, the results indicate that this endophytic plant-bacterium association is far more inclusive, invasive, and dynamic than previously thought, including dissemination in both below-ground and above-ground tissues and enhancement of growth physiology by several rhizobial species, therefore heightening its interest and potential value as a biofertilizer strategy for sustainable agriculture to produce the world's most important cereal crops. PMID:16269768

Chi, Feng; Shen, Shi-Hua; Cheng, Hai-Ping; Jing, Yu-Xiang; Yanni, Youssef G; Dazzo, Frank B

2005-11-01

463

Ascending Migration of Endophytic Rhizobia, from Roots to Leaves, inside Rice Plants and Assessment of Benefits to Rice Growth Physiology  

PubMed Central

Rhizobia, the root-nodule endosymbionts of leguminous plants, also form natural endophytic associations with roots of important cereal plants. Despite its widespread occurrence, much remains unknown about colonization of cereals by rhizobia. We examined the infection, dissemination, and colonization of healthy rice plant tissues by four species of gfp-tagged rhizobia and their influence on the growth physiology of rice. The results indicated a dynamic infection process beginning with surface colonization of the rhizoplane (especially at lateral root emergence), followed by endophytic colonization within roots, and then ascending endophytic migration into the stem base, leaf sheath, and leaves where they developed high populations. In situ CMEIAS image analysis indicated local endophytic population densities reaching as high as 9 × 1010 rhizobia per cm3 of infected host tissues, whereas plating experiments indicated rapid, transient or persistent growth depending on the rhizobial strain and rice tissue examined. Rice plants inoculated with certain test strains of gfp-tagged rhizobia produced significantly higher root and shoot biomass; increased their photosynthetic rate, stomatal conductance, transpiration velocity, water utilization efficiency, and flag leaf area (considered to possess the highest photosynthetic activity); and accumulated higher levels of indoleacetic acid and gibberellin growth-regulating phytohormones. Considered collectively, the results indicate that this endophytic plant-bacterium association is far more inclusive, invasive, and dynamic than previously thought, including dissemination in both below-ground and above-ground tissues and enhancement of growth physiology by several rhizobial species, therefore heightening its interest and potential value as a biofertilizer strategy for sustainable agriculture to produce the world's most important cereal crops.

Chi, Feng; Shen, Shi-Hua; Cheng, Hai-Ping; Jing, Yu-Xiang; Yanni, Youssef G.; Dazzo, Frank B.

2005-01-01

464

Convenient detection of the citrus greening (huanglongbing) bacterium 'Candidatus Liberibacter asiaticus' by direct PCR from the midrib extract.  

PubMed

A phloem-limited bacterium, 'Candidatus Liberibacter asiaticus' (Las) is a major pathogen of citrus greening (huanglongbing), one of the most destructive citrus diseases worldwide. The rapid identification and culling of infected trees and budwoods in quarantine are the most important control measures. DNA amplification including conventional polymerase chain reaction (PCR) has commonly been used for rapid detection and identification. However, long and laborious procedures for DNA extraction have greatly reduced the applicability of this method. In this study, we found that the Las bacterial cells in the midribs of infected leaves were extracted rapidly and easily by pulverization and centrifugation with mini homogenization tubes. We also found that the Las bacterial cells in the midrib extract were suitable for highly sensitive direct PCR. The performance of direct PCR using this extraction method was not inferior to that of conventional PCR. Thus, the direct PCR method described herein is characterized by its simplicity, sensitivity, and robustness, and is applicable to quarantine testing. PMID:23437295

Fujikawa, Takashi; Miyata, Shin-Ichi; Iwanami, Toru

2013-02-20

465

Factors affecting Agrobacterium-mediated transformation in Citrus and production of sour orange (Citrus aurantium L.) plants expressing the coat protein gene of citrus tristeza virus  

Microsoft Academic Search

Factors influencing transformation frequencies using the Agrobacterium-mediated protocol developed for Citrus seedling internodal stem segments in this laboratory were evaluated, with particular emphasis on decreasing the numbers of\\u000a ``escape'' shoots produced. Although the use of a wild-type ``shooty'' Agrobacterium strain allowed relatively high frequencies of ?-glucuronidase positive (GUS+) shoots to be produced, none of the shoots were free of wild-type

D. Luth; G. A. Moore

1997-01-01

466

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- ...

467

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

468

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

469

Changes in sensory properties and consumer acceptance of reduced fat pork Lyon-style and liver sausages containing inulin and citrus fiber as fat replacers.  

PubMed

The effects of fat reduction in Lyon-style (25% fat) and liver sausages (30% fat) using inulin, citrus fiber and partially rice starch were studied in terms of sensory properties and consumer acceptance. Fat reduced Lyon-style sausages (3 to 17% fat) and liver sausages (3 to 20% fat) were respectively compared to the full-fat controls. Reducing fat in Lyon-style sausages decreased meat flavor, aftertaste meat flavor, greasiness and juiciness, and enhanced color intensity, spiciness, spicy aftertaste, raspy throat, coarseness and firmness scores. But adding inulin and citrus fiber led to sensory characteristics similar to the full-fat reference. Regarding liver sausages, attribute scores in greasiness, creaminess, lumpiness and foamy were decreased with fat reduction and simultaneous addition of fibers. Color intensity, spiciness, firmness and attribute furred tongue were increased. Consumer tests revealed acceptable fat reduced (32 to 90% less than control) and fiber enriched (1.0 to 5.6%) sausages. Drivers of liking were found to relate not only to high-fat but also to low-fat samples. PMID:23811098

Tomaschunas, Maja; Zörb, Rebecca; Fischer, Jürgen; Köhn, Ehrhard; Hinrichs, Jörg; Busch-Stockfisch, Mechthild

2013-06-10

470

Role of imidacloprid in integrated pest management of California citrus.  

PubMed

Portions of three commercial citrus orchards were treated for 1 yr with foliar imidacloprid or for 2 yr with a systemic formulation in a replicated plot design to determine the impact of this neonicotinoid on the San Joaquin Valley California citrus integrated pest management (IPM) program. Foliar-applied imidacloprid had little effect on California red scale, Aonidiella aurantii (Maskell); cottony cushion scale, Icerya purchasi Maskell; or citrus red mite, Panonychus citri (McGregor), populations. Short-term suppression of the parasitoids Aphytis melinus DeBach and Comperiella bifasciata Howard; vedalia, Rodolia cardinalis (Mulsant); and the predacious mite Euseius tularensis (Congdon) were observed. Suppression of natural enemies allowed scales and mites to maintain higher populations in the treated areas compared with the nontreated areas. Thus, foliar imidacloprid did not exhibit control of these citrus pest species, and it disrupted biological control. Systemically applied imidacloprid suppressed California red scale and citricola scale populations 2-3 mo after treatment. Suppression of parasitoids of the California red scale also was observed. Thus, treatments of systemic imidacloprid applied in areawide management programs for invasive pests would provide a benefit of California red scale and citricola scale suppression. However, this treatment provided only single-season control of citricola scale, it was somewhat disruptive of biological control, and it did not suppress densities of either scale as low as a treatment of the organophosphate chlorpyrifos for citricola scale or the insect growth regulator pyriproxyfen for California red scale. Insecticides with longer periods of efficacy and greater IPM compatibility than imidacloprid should be used for a sustainable IPM approach in California citrus. PMID:18459411

Grafton-Cardwell, E E; Lee, J E; Robillard, S M; Gorden, J M

2008-04-01

471

In Vitro Fermentation of Cellulose, Beet Pulp, Citrus Pulp, and Citrus Pectin Using Fecal Inoculum from Cats, Dogs, Horses, Humans, and Pigs and Ruminal Fluid from Cattle  

Microsoft Academic Search

We evaluated the influence of gas- trointestinal tract microflora from several species on fiber fermentation characteristics in vitro. Selected fibrous substrates (cellulose, beet pulp, citrus pulp, and citrus pectin) were incubated for 6, 12, 24, and 48 h with ruminal fluid from cattle or feces from dogs, cats, pigs, horses, or humans. When data were pooled across all substrates and

G. D. Sunvold; H. S. Hussein; G. C. Fahey; N. R. Merchen; G. A. Reinhart

2010-01-01

472

VECTOR TRANSMISSION OF THE CAUSAL AGENTS OF CITRUS VARIEGATED CHLOROSIS, HUANGLONGBING AND CITRUS TRISTEZA USING ENDEMIC AND NEWLY ESTABLISHED INSECT SPECIES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus variegated chlorosis (CVC), causal agent Xylella fastidiosa (Xf), huanglongbing (HLB) causal agent Liberobacter spp, and exotic stem pitting isolates of citrus tristeza virus (CTV) are not present in the continental U.S. CVC is transmitted by sharpshooter leafhoppers (Homoptera: Cicadellidae...

473

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

474

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

475

Genetic Transformation of Citrus Paradisi with Antisense and untranslatable RNA-dependent RNA Polymerase Genes of Citrus Tristeza Closterovirus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Expression of the RNA-dependent RNA polymerase (RdRp) of Citrus tristeza virus (CTV) was studied in vivo and in vitro using a polyclonal antiserum raised against the recombinant CTV-RdRp protein. Although 56 kDa CTV-RdRp is thought to be expressed by a +1 translational frameshift at the carboxyl te...

476

Huanglongbing (Citrus Greening) Detection Using Visible, Near Infrared and Thermal Imaging Techniques  

PubMed Central

This study demonstrates the applicability of visible-near infrared and thermal imaging for detection of Huanglongbing (HLB) disease in citrus trees. Visible-near infrared (440–900 nm) and thermal infrared spectral reflectance data were collected from individual healthy and HLB-infected trees. Data analysis revealed that the average reflectance values of the healthy trees in the visible region were lower than those in the near infrared region, while the opposite was the case for HLB-infected trees. Moreover, 560 nm, 710 nm, and thermal band showed maximum class separability between healthy and HLB-infected groups among the evaluated visible-infrared bands. Similarly, analysis of several vegetation indices indicated that the normalized difference vegetation index (NDVI), Vogelmann red-edge index (VOG) and modified red-edge simple ratio (mSR) demonstrated good class separability between the two groups. Classification studies using average spectral reflectance values from the visible, near infrared, and thermal bands (13 spectral features) as input features indicated that an average overall classification accuracy of about 87%, with 89% specificity and 85% sensitivity could be achieved with classification models such as support vector machine for trees with symptomatic leaves.

Sankaran, Sindhuja; Maja, Joe Mari; Buchanon, Sherrie; Ehsani, Reza

2013-01-01

477

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

478

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

479

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

480

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 ...

481

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...

482

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

483

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

484