Reorganization of wheat and rye genomes in octoploid triticale (× Triticosecale).

PubMed

Kalinka, Anna; Achrem, Magdalena

2018-04-01

The analysis of early generations of triticale showed numerous rearrangements of the genome. Complexed transformation included loss of chromosomes, t-heterochromatin content changes and the emergence of retrotransposons in new locations. This study investigated certain aspects of genomic transformations in the early generations (F5 and F8) of the primary octoploid triticale derived from the cross of hexaploid wheat with the diploid rye. Most of the plants tested were hypoploid; among eliminated chromosomes were rye chromosomes 4R and 5R and variable number of wheat chromosomes. Wheat chromosomes were eliminated to a higher extent. The lower content of telomeric heterochromatin was also found in rye chromosomes in comparison with parental rye. Studying the location of selected retrotransposons from Ty1-copia and Ty3-gypsy families using fluorescence in situ hybridization revealed additional locations of these retrotransposons that were not present in chromosomes of parental species. ISSR, IRAP and REMAP analyses showed significant changes at the level of specific DNA nucleotide sequences. In most cases, the disappearance of certain types of bands was observed, less frequently new types of bands appeared, not present in parental species. This demonstrates the scale of genome rearrangement and, above all, the elimination of wheat and rye sequences, largely due to the reduction of chromosome number. With regard to the proportion of wheat to rye genome, the rye genome was more affected by the changes, thus this study was focused more on the rye genome. Observations suggest that genome reorganization is not finished in the F5 generation but is still ongoing in the F8 generation.

Molecular Cytogenetic Characterization of two Triticum-Secale-Thinopyrum Trigeneric Hybrids Exhibiting Superior Resistance to Fusarium Head Blight, Leaf Rust, and Stem Rust Race Ug99.

PubMed

Dai, Yi; Duan, Yamei; Liu, Huiping; Chi, Dawn; Cao, Wenguang; Xue, Allen; Gao, Yong; Fedak, George; Chen, Jianmin

2017-01-01

Fusarium head blight (FHB), leaf rust, and stem rust are the most destructive fungal diseases in current world wheat production. The diploid wheatgrass, Thinopyrum elongatum (Host) Dewey (2 n = 2 x = 14, EE) is an excellent source of disease resistance genes. Two new Triticum-Secale-Thinopyrum trigeneric hybrids were derived from a cross between a hexaploid triticale (X Triticosecale Wittmack, 2 n = 6 x = 42, AABBRR) and a hexaploid Triticum trititrigia (2 n = 6 x = 42, AABBEE), were produced and analyzed using genomic in situ hybridization and molecular markers. The results indicated that line RE21 contained 14 A-chromosomes, 14 B-chromosomes, three pairs of R-chromosomes (4R, 6R, and 7R), and four pairs of E-chromosomes (1E, 2E, 3E, and 5E) for a total chromosome number of 2 n = 42. Line RE62 contained 14 A-chromosomes, 14 B-chromosomes, six pairs of R-chromosomes, and one pair of translocation chromosomes between chromosome 5R and 5E, for a total chromosome number of 2 n = 42. At the seedling and adult growth stages under greenhouse conditions, line RE21 showed high levels of resistance to FHB, leaf rust, and stem rust race Ug99, and line RE62 was highly resistant to leaf rust and stem rust race Ug99. These two lines (RE21 and RE62) display superior disease resistance characteristics and have the potential to be utilized as valuable germplasm sources for future wheat improvement.

Carbon and nitrogen partitioning during the post-anthesis period is conditioned by N fertilisation and sink strength in three cereals.

PubMed

Aranjuelo, I; Cabrera-Bosquet, L; Araus, J L; Nogués, S

2013-01-01

Further knowledge of the processes conditioning nitrogen use efficiency (NUE) is of great relevance to crop productivity. The aim of this paper was characterise C and N partitioning during grain filling and their implications for NUE. Cereals such as bread wheat (Triticum aestivum L. cv Califa sur), triticale (× Triticosecale Wittmack cv. Imperioso) and tritordeum (× Tritordeum Asch. & Graebn line HT 621) were grown under low (LN, 5 mm NH(4) NO(3)) and high (HN, 15 mm NH(4)NO(3)) N conditions. We conducted simultaneous double labelling ((12)CO(2) and (15)NH(4) (15)NO(3)) in order to characterise C and N partitioning during grain filling. Although triticale plants showed the largest total and ear dry matter values in HN conditions, the large investment in shoot and root biomass negatively affected ear NUE. Tritordeum was the only genotype that increased NUE in both N treatments (NUE(total)), whereas in wheat, no significant effect was detected. N labelling revealed that N fertilisation during post-anthesis was more relevant for wheat and tritordeum grain filling than for triticale. The study also revealed that the investments of C and N in flag leaves and shoots, together with the 'waste' of photoassimilates in respiration, conditioned the NUE of plants, and especially under LN. These results suggest that C and N use by these plants needs to be improved in order to increase ear C and N sinks, especially under LN. It is also remarkable that even though tritordeum shows the largest increase in NUE, the low yield of this cereal limits its agronomic value. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

BreedVision--a multi-sensor platform for non-destructive field-based phenotyping in plant breeding.

PubMed

Busemeyer, Lucas; Mentrup, Daniel; Möller, Kim; Wunder, Erik; Alheit, Katharina; Hahn, Volker; Maurer, Hans Peter; Reif, Jochen C; Würschum, Tobias; Müller, Joachim; Rahe, Florian; Ruckelshausen, Arno

2013-02-27

To achieve the food and energy security of an increasing World population likely to exceed nine billion by 2050 represents a major challenge for plant breeding. Our ability to measure traits under field conditions has improved little over the last decades and currently constitutes a major bottleneck in crop improvement. This work describes the development of a tractor-pulled multi-sensor phenotyping platform for small grain cereals with a focus on the technological development of the system. Various optical sensors like light curtain imaging, 3D Time-of-Flight cameras, laser distance sensors, hyperspectral imaging as well as color imaging are integrated into the system to collect spectral and morphological information of the plants. The study specifies: the mechanical design, the system architecture for data collection and data processing, the phenotyping procedure of the integrated system, results from field trials for data quality evaluation, as well as calibration results for plant height determination as a quantified example for a platform application. Repeated measurements were taken at three developmental stages of the plants in the years 2011 and 2012 employing triticale (×Triticosecale Wittmack L.) as a model species. The technical repeatability of measurement results was high for nearly all different types of sensors which confirmed the high suitability of the platform under field conditions. The developed platform constitutes a robust basis for the development and calibration of further sensor and multi-sensor fusion models to measure various agronomic traits like plant moisture content, lodging, tiller density or biomass yield, and thus, represents a major step towards widening the bottleneck of non-destructive phenotyping for crop improvement and plant genetic studies.

Higher sterol content regulated by CYP51 with concomitant lower phospholipid content in membranes is a common strategy for aluminium tolerance in several plant species.

PubMed

Wagatsuma, Tadao; Khan, Md Shahadat Hossain; Watanabe, Toshihiro; Maejima, Eriko; Sekimoto, Hitoshi; Yokota, Takao; Nakano, Takeshi; Toyomasu, Tomonobu; Tawaraya, Keitaro; Koyama, Hiroyuki; Uemura, Matsuo; Ishikawa, Satoru; Ikka, Takashi; Ishikawa, Akifumi; Kawamura, Takeshi; Murakami, Satoshi; Ueki, Nozomi; Umetsu, Asami; Kannari, Takayuki

2015-02-01

Several studies have shown that differences in lipid composition and in the lipid biosynthetic pathway affect the aluminium (Al) tolerance of plants, but little is known about the molecular mechanisms underlying these differences. Phospholipids create a negative charge at the surface of the plasma membrane and enhance Al sensitivity as a result of the accumulation of positively charged Al(3+) ions. The phospholipids will be balanced by other electrically neutral lipids, such as sterols. In the present research, Al tolerance was compared among pea (Pisum sativum) genotypes. Compared with Al-tolerant genotypes, the Al-sensitive genotype accumulated more Al in the root tip, had a less intact plasma membrane, and showed a lower expression level of PsCYP51, which encodes obtusifoliol-14α-demethylase (OBT 14DM), a key sterol biosynthetic enzyme. The ratio of phospholipids to sterols was higher in the sensitive genotype than in the tolerant genotypes, suggesting that the sterol biosynthetic pathway plays an important role in Al tolerance. Consistent with this idea, a transgenic Arabidopsis thaliana line with knocked-down AtCYP51 expression showed an Al-sensitive phenotype. Uniconazole-P, an inhibitor of OBT 14DM, suppressed the Al tolerance of Al-tolerant genotypes of maize (Zea mays), sorghum (Sorghum bicolor), rice (Oryza sativa), wheat (Triticum aestivum), and triticale (×Triticosecale Wittmark cv. Currency). These results suggest that increased sterol content, regulated by CYP51, with concomitant lower phospholipid content in the root tip, results in lower negativity of the plasma membrane. This appears to be a common strategy for Al tolerance among several plant species. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

BreedVision — A Multi-Sensor Platform for Non-Destructive Field-Based Phenotyping in Plant Breeding

PubMed Central

Busemeyer, Lucas; Mentrup, Daniel; Möller, Kim; Wunder, Erik; Alheit, Katharina; Hahn, Volker; Maurer, Hans Peter; Reif, Jochen C.; Würschum, Tobias; Müller, Joachim; Rahe, Florian; Ruckelshausen, Arno

2013-01-01

To achieve the food and energy security of an increasing World population likely to exceed nine billion by 2050 represents a major challenge for plant breeding. Our ability to measure traits under field conditions has improved little over the last decades and currently constitutes a major bottleneck in crop improvement. This work describes the development of a tractor-pulled multi-sensor phenotyping platform for small grain cereals with a focus on the technological development of the system. Various optical sensors like light curtain imaging, 3D Time-of-Flight cameras, laser distance sensors, hyperspectral imaging as well as color imaging are integrated into the system to collect spectral and morphological information of the plants. The study specifies: the mechanical design, the system architecture for data collection and data processing, the phenotyping procedure of the integrated system, results from field trials for data quality evaluation, as well as calibration results for plant height determination as a quantified example for a platform application. Repeated measurements were taken at three developmental stages of the plants in the years 2011 and 2012 employing triticale (×Triticosecale Wittmack L.) as a model species. The technical repeatability of measurement results was high for nearly all different types of sensors which confirmed the high suitability of the platform under field conditions. The developed platform constitutes a robust basis for the development and calibration of further sensor and multi-sensor fusion models to measure various agronomic traits like plant moisture content, lodging, tiller density or biomass yield, and thus, represents a major step towards widening the bottleneck of non-destructive phenotyping for crop improvement and plant genetic studies. PMID:23447014

Yield performance and stability of CMS-based triticale hybrids.

PubMed

Mühleisen, Jonathan; Piepho, Hans-Peter; Maurer, Hans Peter; Reif, Jochen Christoph

2015-02-01

CMS-based triticale hybrids showed only marginal midparent heterosis for grain yield and lower dynamic yield stability compared to inbred lines. Hybrids of triticale (×Triticosecale Wittmack) are expected to possess outstanding yield performance and increased dynamic yield stability. The objectives of the present study were to (1) examine the optimum choice of the biometrical model to compare yield stability of hybrids versus lines, (2) investigate whether hybrids exhibit a more pronounced grain yield performance and yield stability, and (3) study optimal strategies to predict yield stability of hybrids. Thirteen female and seven male parental lines and their 91 factorial hybrids as well as 30 commercial lines were evaluated for grain yield in up to 20 environments. Hybrids were produced using a cytoplasmic male sterility (CMS)-inducing cytoplasm that originated from Triticumtimopheevii Zhuk. We found that the choice of the biometrical model can cause contrasting results and concluded that a group-by-environment interaction term should be added to the model when estimating stability variance of hybrids and lines. midparent heterosis for grain yield was on average 3 % with a range from -15.0 to 11.5 %. No hybrid outperformed the best inbred line. Hybrids had, on average, lower dynamic yield stability compared to the inbred lines. Grain yield performance of hybrids could be predicted based on midparent values and general combining ability (GCA)-predicted values. In contrast, stability variance of hybrids could be predicted only based on GCA-predicted values. We speculated that negative effects of the used CMS cytoplasm might be the reason for the low performance and yield stability of the hybrids. For this purpose a detailed study on the reasons for the drawback of the currently existing CMS system in triticale is urgently required comprising also the search of potentially alternative hybridization systems.

Biochemical characterization of the triticale TsPAP1, a new type of plant prolyl aminopeptidase, and its impact on proline content and flowering time in transgenic Arabidopsis plants.

PubMed

Zdunek-Zastocka, Edyta; Grabowska, Agnieszka; Branicki, Tomasz; Michniewska, Beata

2017-07-01

Proline aminopeptidase (PAP, EC 3.4.11.5) is the only enzyme that effectively releases proline from the N-termini of peptides. The amino acid sequence of the PAP from Triticosecale, TsPAP1, comprises conserved regions, characteristic of the monomeric forms of PAP found in bacteria but not yet identified in plants. Therefore, we aimed to obtain and biochemically characterize the TsPAP1 protein. The recombinant TsPAP1 protein was received through heterologous expression of the TsPAP1 coding sequence in a bacterial expression system and purified with affinity chromatography. Gel filtration chromatography and SDS electrophoresis revealed that TsPAP1 is a monomer with a molecular mass of 37.5 kDa. TsPAP1 prefers substrates with proline at the N-terminus but is also capable of hydrolyzing β-naphthylamides of hydroxyproline and alanine. Among the peptides tested, the most preferred were di- and tripeptides, especially those with glycine in the Y position. The use of diagnostic inhibitors indicated that TsPAP1 is a serine peptidase; however, further characterization revealed that the SH residues are also important for maintaining its activity. To examine the role of TsPAP1 under physiological conditions, we developed transgenic Arabidopsis plants overexpressing TsPAP1. Compared with wild-type plants, the transgenic lines accumulated more proline, flowered an average of 3.5 days earlier, and developed more siliques than did untransformed controls. Our paper is the first to describe the biochemical properties of a novel monomeric plant PAP and contributes to the functional characterization of PAP proteins in plants. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

The Agrobacterium-mediated transformation of common wheat (Triticum aestivum L.) and triticale (x Triticosecale Wittmack): role of the binary vector system and selection cassettes.

PubMed

Bińka, Agnieszka; Orczyk, Wacław; Nadolska-Orczyk, Anna

2012-02-01

The influence of two binary vector systems, pGreen and pCAMBIA, on the Agrobacterium-mediated transformation ability of wheat and triticale was studied. Both vectors carried selection cassettes with bar or nptII driven by different promoters. Two cultivars of wheat, Kontesa and Torka, and one cultivar of triticale, Wanad, were tested. The transformation rates for the wheat cultivars ranged from 0.00 to 3.58% and from 0.00 to 6.79% for triticale. The best values for wheat were 3.58% for Kontesa and 3.14% for Torka, and these were obtained after transformation with the pGreen vector carrying the nptII selection gene under the control of 35S promoter. In the case of the bar selection system, the best transformation rates were, respectively, 1.46 and 1.79%. Such rates were obtained when the 35S::bar cassette was carried by the pCAMBIA vector; they were significantly lower with the pGreen vector. The triticale cultivar Wanad had its highest transformation rate after transformation with nptII driven by 35S in pCAMBIA. The bar selection system for the same triticale cultivar was better when the gene was driven by nos and the selection cassette was carried by pGreen. The integration of the transgenes was confirmed with at least three pairs of specific starters amplifying the fragments of nptII, bar, or gus. The expression of selection genes, measured by reverse transcriptase polymerase chain reaction (RT-PCR) in relation to the actin gene, was low, ranging from 0.00 to 0.63 for nptII and from 0.00 to 0.33 for bar. The highest relative transcript accumulation was observed for nptII driven by 35S and expressed in Kontesa that had been transformed with pGreen.

Gametocidal Factor Transferred from Aegilops geniculata Roth Can Be Adapted for Large-Scale Chromosome Manipulations in Cereals

PubMed Central

Kwiatek, Michał T.; Wiśniewska, Halina; Ślusarkiewicz-Jarzina, Aurelia; Majka, Joanna; Majka, Maciej; Belter, Jolanta; Pudelska, Hanna

2017-01-01

Segregation distorters are curious, evolutionarily selfish genetic elements, which distort Mendelian segregation in their favor at the expense of others. Those agents include gametocidal factors (Gc), which ensure their preferential transmission by triggering damages in cells lacking them via chromosome break induction. Hence, we hypothesized that the gametocidal system can be adapted for chromosome manipulations between Triticum and Secale chromosomes in hexaploid triticale (×Triticosecale Wittmack). In this work we studied the little-known gametocidal action of a Gc factor located on Aegilops geniculata Roth chromosome 4Mg. Our results indicate that the initiation of the gametocidal action takes place at anaphase II of meiosis of pollen mother cells. Hence, we induced androgenesis at postmeiotic pollen divisions (via anther cultures) in monosomic 4Mg addition plants of hexaploid triticale (AABBRR) followed by production of doubled haploids, to maintain the chromosome aberrations caused by the gametocidal action. This approach enabled us to obtain a large number of plants with two copies of particular chromosome translocations, which were identified by the use of cytomolecular methods. We obtained 41 doubled haploid triticale lines and 17 of them carried chromosome aberrations that included plants with the following chromosome sets: 40T+Dt2RS+Dt2RL (5 lines), 40T+N2R (1), 38T+D4RS.4BL (3), 38T+D5BS-5BL.5RL (5), and 38T+D7RS.3AL (3). The results show that the application of the Gc mechanism in combination with production of doubled haploid lines provides a sufficiently large population of homozygous doubled haploid individuals with two identical copies of translocation chromosomes. In our opinion, this approach will be a valuable tool for the production of novel plant material, which could be used for gene tracking studies, genetic mapping, and finally to enhance the diversity of cereals. PMID:28396677

Evaluation of crossability between triticale (X Triticosecale Wittmack) and common wheat, durum wheat and rye.

PubMed

Hills, Melissa J; Hall, Linda M; Messenger, Doug F; Graf, Robert J; Beres, Brian L; Eudes, François

2007-01-01

Development of transgenic triticale as a platform for novel bio-industrial products is predicated on an environmental biosafety assessment that quantifies the potential risks associated with its release. Pollen-mediated gene flow to related species and conventional triticale varieties is one pathway for transgene movement. A tier 1 quantification of triticale hybridization was conducted by emasculating and hand pollinating flowers under greenhouse conditions. Approximately 2000 manual pollinations were conducted for each cross and its reciprocal between two triticale genotypes: a modern triticale cultivar (AC Alta) and primary triticale (89TT108), and common wheat, durum wheat and rye. The frequency of outcrossing, hybrid seed appearance and weight, and F(1) emergence and fertility were recorded. Outcrossing, F(1) emergence and fertility rates were high from crosses between triticale genotypes. Outcrossing in inter-specific crosses was influenced by the species, and the genotype and gender of the triticale parent. In crosses to common and durum wheat where triticale was the male parent, outcrossing was > or =73.0% and > or =69.5%, respectively, but < or =23.9% and < or =3.0% when triticale was the female parent. Overall, outcrossing with rye was lower than with common and durum wheat. F(1) hybrid emergence was greater when triticale was the female parent. With the exception of a single seed, all wheat-triticale F(1) hybrid seeds were non-viable when triticale was the male parent in the cross. Only seven durum wheat-triticale F(1) hybrids emerged from 163 seeds sown, and all were produced with triticale 89TT108 as female parent. With rye, 8 F(1) hybrids emerged from 38 seeds sown, and all were produced from crosses to AC Alta; five with AC Alta as the female parent and three as the male. Interspecific F(1) hybrids were self-sterile, with the exception of those produced in crosses between common wheat and triticale where triticale was the female parent. Tier 2 hybridization quantification will be conducted under field conditions.

Sina and Sinb genes in triticale do not determine grain hardness contrary to their orthologs Pina and Pinb in wheat

PubMed Central

2013-01-01

Background Secaloindoline a (Sina) and secaloindoline b (Sinb) genes of hexaploid triticale (x Triticosecale Wittmack) are orthologs of puroindoline a (Pina) and puroindoline b (Pinb) in hexaploid wheat (Triticum aestivum L.). It has already been proven that RNA interference (RNAi)-based silencing of Pina and Pinb genes significantly decreased the puroindoline a and puroindoline b proteins in wheat and essentially increased grain hardness (J Exp Bot 62:4025-4036, 2011). The function of Sina and Sinb in triticale was tested by means of RNAi silencing and compared to wheat. Results Novel Sina and Sinb alleles in wild-type plants of cv. Wanad were identified and their expression profiles characterized. Alignment with wheat Pina-D1a and Pinb-D1a alleles showed 95% and 93.3% homology with Sina and Sinb coding sequences. Twenty transgenic lines transformed with two hpRNA silencing cassettes directed to silence Sina or Sinb were obtained by the Agrobacterium-mediated method. A significant decrease of expression of both Sin genes in segregating progeny of tested T1 lines was observed independent of the silencing cassette used. The silencing was transmitted to the T4 kernel generation. The relative transcript level was reduced by up to 99% in T3 progeny with the mean for the sublines being around 90%. Silencing of the Sin genes resulted in a substantial decrease of secaloindoline a and secaloindoline b content. The identity of SIN peptides was confirmed by mass spectrometry. The hardness index, measured by the SKCS (Single Kernel Characterization System) method, ranged from 22 to 56 in silent lines and from 37 to 49 in the control, and the mean values were insignificantly lower in the silent ones, proving increased softness. Additionally, the mean total seed protein content of silenced lines was about 6% lower compared with control lines. Correlation coefficients between hardness and transcript level were weakly positive. Conclusions We documented that RNAi-based silencing of Sin genes resulted in significant decrease of their transcripts and the level of both secaloindoline proteins, however did not affect grain hardness. The unexpected, functional differences of Sin genes from triticale compared with their orthologs, Pin of wheat, are discussed. PMID:24279512

Sina and Sinb genes in triticale do not determine grain hardness contrary to their orthologs Pina and Pinb in wheat.

PubMed

Gasparis, Sebastian; Orczyk, Waclaw; Nadolska-Orczyk, Anna

2013-11-26

Secaloindoline a (Sina) and secaloindoline b (Sinb) genes of hexaploid triticale (x Triticosecale Wittmack) are orthologs of puroindoline a (Pina) and puroindoline b (Pinb) in hexaploid wheat (Triticum aestivum L.). It has already been proven that RNA interference (RNAi)-based silencing of Pina and Pinb genes significantly decreased the puroindoline a and puroindoline b proteins in wheat and essentially increased grain hardness (J Exp Bot 62:4025-4036, 2011). The function of Sina and Sinb in triticale was tested by means of RNAi silencing and compared to wheat. Novel Sina and Sinb alleles in wild-type plants of cv. Wanad were identified and their expression profiles characterized. Alignment with wheat Pina-D1a and Pinb-D1a alleles showed 95% and 93.3% homology with Sina and Sinb coding sequences. Twenty transgenic lines transformed with two hpRNA silencing cassettes directed to silence Sina or Sinb were obtained by the Agrobacterium-mediated method. A significant decrease of expression of both Sin genes in segregating progeny of tested T1 lines was observed independent of the silencing cassette used. The silencing was transmitted to the T4 kernel generation. The relative transcript level was reduced by up to 99% in T3 progeny with the mean for the sublines being around 90%. Silencing of the Sin genes resulted in a substantial decrease of secaloindoline a and secaloindoline b content. The identity of SIN peptides was confirmed by mass spectrometry. The hardness index, measured by the SKCS (Single Kernel Characterization System) method, ranged from 22 to 56 in silent lines and from 37 to 49 in the control, and the mean values were insignificantly lower in the silent ones, proving increased softness. Additionally, the mean total seed protein content of silenced lines was about 6% lower compared with control lines. Correlation coefficients between hardness and transcript level were weakly positive. We documented that RNAi-based silencing of Sin genes resulted in significant decrease of their transcripts and the level of both secaloindoline proteins, however did not affect grain hardness. The unexpected, functional differences of Sin genes from triticale compared with their orthologs, Pin of wheat, are discussed.

Inclusion of wheat and triticale silage in the diet of lactating dairy cows.

PubMed

Harper, M T; Oh, J; Giallongo, F; Roth, G W; Hristov, A N

2017-08-01

The objective of this experiment was to partially replace corn silage with 2 alternative forages, wheat (Triticum aestivum) or triticale (X Triticosecale) silages at 10% of the diet dry matter (DM), and investigate the effects on dairy cow productivity, nutrient utilization, enteric CH 4 emissions, and farm income over feed costs. Wheat and triticale were planted in the fall as cover crops and harvested in the spring at the boot stage. Neutral- and acid-detergent fiber and lignin concentrations were higher in the wheat and triticale silages compared with corn silage. The forages had similar ruminal in situ effective degradability of DM. Both alternative forages had 1% starch or less compared with the approximately 35% starch in corn silage. Diets with the alternative forages were fed in a replicated 3 × 3 Latin square design experiment with three 28-d periods and 12 Holstein cows. The control diet contained 44% (DM basis) corn silage. In the other 2 diets, wheat or triticale silages were included at 10% of dietary DM, replacing corn silage. Dry matter intake was not affected by diet, but both wheat and triticale silage decreased yield of milk (41.4 and 41.2 vs. 42.7 ± 5.18 kg/d) and milk components, compared with corn silage. Milk fat from cows fed the alternative forage diets contained higher concentrations of 4:0, 6:0, and 18:0 and tended to have lower concentrations of total trans fatty acids. Apparent total-tract digestibility of DM and organic matter was decreased in the wheat silage diet, and digestibility of neutral-and acid-detergent fiber was increased in the triticale silage diet. The wheat and triticale silage diets resulted in higher excretion of urinary urea, higher milk urea N, and lower milk N efficiency compared with the corn silage diet. Enteric CH 4 emission per kilogram of energy-corrected milk was highest in the triticale silage diet, whereas CO 2 emission was decreased by both wheat and triticale silage. This study showed that, at milk production of around 42 kg/d, wheat silage and triticale silage can partially replace corn silage DM and not affect DM intake, but milk yield may decrease slightly. For dairy farms in need of more forage, triticale or wheat double cropped with corn silage may be an appropriate cropping strategy. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Productivity and nutrient cycling in bioenergy cropping systems

NASA Astrophysics Data System (ADS)

Heggenstaller, Andrew Howard

One of the greatest obstacles confronting large-scale biomass production for energy applications is the development of cropping systems that balance the need for increased productive capacity with the maintenance of other critical ecosystem functions including nutrient cycling and retention. To address questions of productivity and nutrient dynamics in bioenergy cropping systems, we conducted two sets of field experiments during 2005-2007, investigating annual and perennial cropping systems designed to generate biomass energy feedstocks. In the first experiment we evaluated productivity and crop and soil nutrient dynamics in three prototypical bioenergy double-crop systems, and in a conventionally managed sole-crop corn system. Double-cropping systems included fall-seeded forage triticale (x Triticosecale Wittmack), succeeded by one of three summer-adapted crops: corn (Zea mays L.), sorghum-sudangrass [Sorghum bicolor (L.) Moench], or sunn hemp (Crotalaria juncea L.). Total dry matter production was greater for triticale/corn and triticale/sorghum-sudangrass compared to sole-crop corn. Functional growth analysis revealed that photosynthetic duration was more important than photosynthetic efficiency in determining biomass productivity of sole-crop corn and double-crop triticale/corn, and that greater yield in the tiritcale/corn system was the outcome of photosynthesis occurring over an extended duration. Increased growth duration in double-crop systems was also associated with reductions in potentially leachable soil nitrogen relative to sole-crop corn. However, nutrient removal in harvested biomass was also greater in the double-crop systems, indicating that over the long-term, double-cropping would mandate increased fertilizer inputs. In a second experiment we assessed the effects of N fertilization on biomass and nutrient partitioning between aboveground and belowground crop components, and on carbon storage by four perennial, warm-season grasses: big bluestem (Andropogon geradii Vitman), switchgrass (Panicum virgatum L.), indiangrass [ Sorghastrum nutans (L.) Nash], and eastern gamagrass (Tripsacum dactyloides L.). Generally, the optimum rate of fertilization for biomass yield by the grasses was 140 kg N ha-1. Nitrogen inputs also had pronounced but grass-specific effects on biomass and nutrient partitioning, and on carbon storage. For big bluestem and switchgrass, 140 kg N ha -1. maximized root biomass, favored allocation of nutrients to roots over shoots, and led to net increases in carbon storage over the study duration. In contrast, for indiangrass and eastern gamagrass, root biomass and root nutrient allocation were generally adversely affected by N fertilization and carbon storage increased only with 0 or 65 kg N ha-1. For all grasses, 220 kg N ha -1 tended to shift allocation of nutrients to shoots over roots and resulted in no net increase in carbon storage. Optimal nitrogen management strategies for perennial, warm-season grass energy crops should take into consideration the effects of N on biomass yield as well as factors such as nutrient and carbon balance that will also impact economic feasibility and environmental sustainability.

The nitrogen efficiency of MSW composts as measured by triticale uptake in a 3-year field experiment

NASA Astrophysics Data System (ADS)

Weber, Jerzy; Licznar, Michal; Bekier, Jakub; Drozd, Jerzy; Jamroz, Elzbieta; Kocowicz, Andrzej; Parylak, Danuta; Kordas, Leszek; Licznar, Stanislawa

2010-05-01

This paper presents results of three year field experiment, where two different composts produced from municipal solid wastes were applied to sandy soil. The experiment was established on soil developed from loam sand, according to U.S.D.A. textural classes (81% of sand, 12% of silt, and 7% of clay), of a slightly acidic reaction (pH KCl 6.05 - 6.44). The plough layer (0 - 25 cm) contained about 5.0 g/kg of organic carbon. Both composts were alkaline in reaction and contained high amounts of plant available forms of phosphorus, potassium and magnesium. Composts were used non-recurrently in rates of 18, 36, and 72 t/ha, calculated on dry matter basis. Control objects (0 and NPK) were plots without fertilization, as well as plots fertilized each year with mineral forms of NPK. Field experiment was conducted in 15 m2 plots, using five replications in a randomized block design. Spring triticale (x Triticosecale Wittm.) cultivated in a 3-year monoculture was used as the experiment plant. Soil samples were collected each year after harvesting. Changes in triticale yield were considered in relation to soil properties and nitrogen content in triticale straw and grain. Application of composts caused beneficial changes in soil fertility, connected mainly with an increase of soil organic matter and content of available forms of P, K, and Mg. These effects were observed throughout three years of the experiment. However, significantly higher values of organic carbon - as compared to control (0 and NPK) - were observed only in plots with medium and highest compost doses. This effect was very clear in the first year, while significant differences in soil carbon content were still observed in next two years. The yield of triticale straw and grain depended significantly on fertilization with composts, but beneficial effect of compost was observed only in the first year. Yield similar to NPK control was found only on plots where the highest dose of compost was applied. Next two years, all compost amended plots indicated distinctly lower yield than that on NPK control. Decrease of yield was accompanied by decreased level of nitrogen in triticale straw and grain, although soil of compost amended and NPK fertilized plots indicated the same level of total nitrogen. In the third year dramatic decrease of soil total nitrogen was observed in (0) control, as result of exhausting available nitrogen, while soil amended with composts still contained nitrogen present in non-mineralized organic matter. The yield of triticale grown on soil amended with compost produced from municipal solid wastes was limited by not sufficient amount of plant available nitrogen. Nitrogen efficiency measured as amount of N taken up by triticale grain and straw - after depriving N uptake by triticale grown on control (0) - was very low, around 3 % in the first year and around 1% in the third year. Application of MSW composts is a good alternative for mineral fertilization, however supplementary fertilization with mineral nitrogen is necessary, depending on compost dose and quality.

Liming and Fertilization Effects on Triticale (XTriticosecale W.) Yield Between 1999 and 2006

NASA Astrophysics Data System (ADS)

László Phd, M., ,, Dr.

2009-04-01

Precipitation amount, distribution and nitrogen (N)-, phosphorus (P2O5)-, potassium (K2O)-, calcium (CaO)-, and magnesium (MgO) fertilization interaction effects were studied on a sandy acidic lessivated brown forest soil; WRB: Haplic Luvisol in the 44 year old Nyírlugos Field Trial (NYFT) in a Hungarian fragile agro-ecosystem in Nyírség region (N: 470 41' 60'' and E: 220 2' 80'') on triticale (X Triticosecale W.) yield from 1999 to 2006. At the trial set up in 1962, the soil had the following agrochemical properties: pH (H2O) 5.9, pH (KCl) 4.7, hydrolytic acidity 8.4, hy1 0.3, humus 0.7%, total N 34 mg kg-1, ammonlactate (AL) soluble-P2O5 43 mg kg-1, AL-K2O 60 mg kg-1 in the plowed (0-25 cm) layer. From 1980 to 2006, the experiment consisted of 32x4=128 plots in randomised block design. The gross plot size was 10x5=50 m2. The average fertilizer rates in kg ha-1 year-1 were nitrogen 75, phosphorus 90 (P2O5), potassium 90 (K2O), calcium 437.5 (CaCO3) and magnesium 140 (MgCO3). The groundwater table has had at a depth of 2-3 m below the surface. The main results are as follows. During drought conditions the respective yield of the control areas was -25% less than for average years. The application of N alone, or of NP and NK treatments, led to yield reduction of -19.7%, while that of NPK, NPKCa, NPKMg or NPKCaMg caused an -28.3% drop during these types of years. In the wet years, the yield decreased by -22.2% on the unfertilized soils; in the case of N, NP, or NK nutrition with an -14.1%; and increased at 13.8% on NPK, NPKCa, NPKMg and NPKCaMg treated plots. In the very wettest year, the yields were dropped -43.1% on control soils, -39.3% of N, NP, or NK loadings and -35.8% on NPK, NPKCa, NPKMg and NPKCaMg treatments to those in the average year. The relationships between rainfall quantitiy during the vegetation period N, P, K, Ca and Mg nutrition and yield were characterised by polynomial correlations (control: R= 0.7212***, N: R = 0.7410***, NP: R = 0.6452***, NK: R = 0.6998***, NPK: R = 0.5555***, NPKCa: R = 0.5578***, NPKMg: R = 0.4869**, NPKCaMg: R = 0.4341**). However, the total regression coefficients ranged from 0.43 to 0.74 in depence on the different nutrient application. Maximum yields of 5.8-6.0 t . ha-1 were achieved in the rainfall range of 580-620 mm. At values above and below this domain of the precipitation the grain yield reduced quadratically. So, it can be stated that both, drought and excess rainfall conditions resulted dramatically in significant negative effects between fertilization (N, P, K, Ca, Mg) and triticale yield. Keywords: precipitation, fertilization, liming, triticale, yield Introduction: The hazards associated with climate change are depend on the interaction of several systems with many variables (Johnston, 2000). Accummulation of carbon dioxide, methane, water vapor, ozone, nitrous oxide, sulfur hexafluoride, hydrofluorocarbons, perfluorocarbons, chlorofluorocarbons (build-up of greenhouse gases) in the atmosphere and trends in their emissions suggest that we can expect significant environmental changes in the 21th century (Cynthia and Ana, 2006; Eric 2006). However, a recent consensus has emerged that between the greenhouse gases rising of atmospheric concentrations of carbon dioxide could become the more dangerous bacause it causing the global warming (Láng, 2005). Today, most researchers believe that higher temperature, drought and rainfall excess caused by climate change will depress crop yields in many places in the coming decades (Kádár et al., 2000; Jolánkai, 2005). Thus, in the last decades many agricultural investigations focused on understanding the relation between mean climate change and crop production (Runge, 1968; Várallyay, 1992). Changes in weather patterns were observed thoughout Europe including Hungary as early as 1850. Among the natural consequences of changing weather patterns, years of drought (rainfall deficit) and wet (rainfall excess) conditions, resulted in problems among plant nutrition and field crop production (EU, 2003). Triticale (Kádár et al., 1999; Márton, 2002) is a crop of worldwide importance, limited research exists about the effects of climate change on these crop. The crop is sensitive to the prevailing weather conditions (such as rainfall) and, for this reason, understanding the effects of anthropogenic climate change on it's production is important (Márton, 2006). In addition to growing season triticale conditions (e.g., soil agrochemical properties, fertilization, liming) affect the growth and yield of crop (Lobell and Asner, 2003) and cause yield variations. Understanding the fertilization, liming and rainfall effects have been a continuous endeavor toward improving farming technology and management strategy to reduce the negative impacts of fertilization, liming and rainfall and to increase crop yield (Kádár and Szemes 1994; Várallyay 1994; among others). Our main objective of this research it was study and clarify the precipitation amount and distribution and nitrogen (N)-, phosphorus (P2O5)-, potassium (K2O)-, calcium (CaO)-, and magnesium (MgO) fertilization interaction effects on a sandy acidic lessivated brown forest soil; WRB: Haplic Luvisol in the 44 year old Nyírlugos field trial in a Hungarian fragile agro-ecosystem in Nyírség region on triticale (X Triticosecale W.) yield from 1999 to 2006. Furthermore, it was our intent to emphasize that the net effect of multiple environmental changes is far more important than the effect of a single factor on the crop. Materials and Methods: The net-influence of rainfall (quantity, distribution) and mineral fertilization (N, P2O5, K2O, CaO, MgO) were studied in a long term field experiment established at the Research Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences Experiment Station (RISSAC-HAS ET) in Hungary on a Haplic Luvisol (sandy acidic lessivated brown forest soil) with triticale (X Triticosecale W.) indicator crop under fragile agro-ecological circumstances at Nyírlugos for 8 years from 1999 to 2006. The main experiment's soil agrochemical characteristics in the plowed (0-25 cm) layer are presented in Table 1. at the experimental set up in 1962 (Láng, 1973). From 1980 to 2006 the experiment consisted of 32x4=128 plots in randomized block designs. The gross plot size has been having 10x5=50 m2. The experimental treatments and combinations are shown in Table 2. The fertilizers were applied in the form of 25% calcium ammonium nitrate, 18% superphosphate, 40% potassium chloride, calcium carbonate and magnesium sulphate. The groundwater table has had at a depth of 2-3 m below the surface. The plant samples had had taken by manually at the harvest time. Rainfall amounts (deviation in rainfall from the average over many years: dry year -10 - -20%, drought year -20% over, wet year +10 - +20%, year with excess rainfall +20% over) and other related data determined on traditional Hungarian (Harnos, 1993) and Research Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences (Márton, 2004) standards, and MANOVA (Multivariate Analysis of Variance) by SPSS test (SPSS Inc., 2000). Table 1: The main soil agrochemical properties in the plowed (0-25 cm) layer at the experiment set up. (Brown forest soil, acid sand; WRB: Haplic Luvisol, Nyírség region Nyírlugos 1962) Content PH HA* Hy1 Humus Total AL** (H2O) (KCl) nitrogen P2O5 K2O 5.9 4.7 8.4 0.3 % 0.7 mg . kg-1 34 43 60 * Hydrolytic acidity, ** ammoniumlactate (AL) soluble Table 2: Fertilization and liming treatments in the experiments, kg ha-1 year-1 (Brown forest soil, acid sand; WRB: Haplic Luvisol, Nyírség region Nyírlugos) TreatmentLevels Applied kg ha-1 yr-1 N P2O5 K2O CaCO3 MgCO3 0 0 0 0 0 0 1 50 60 60 250 140 2 100 120 120 500 280 3 150 180 180 1000 - Note: In the form of Ca-ammonium-nitrate, Superphosphate, potassium cloride, powdered limestone and dolomite. Results and Discussion: During drought conditions, in conformity with Adams et al. (1995), Rosenzweig and Tubiello (1997) and McMaster (1999) the respective yield of the control areas was -25% less than for average years. The application of N alone, or of NP and NK treatments, led to yield losses of -19.6%, while that of NPK, NPKCa, NPKMg or NPKCaMg caused an -28.3% drop during these types of years. In the wet years, the yield decreased by -22.2% in the unfertilized plots; in the case of N, NP, or NK nutrition with an -14.1%; and increased at 13.8% on NPK, NPKCa, NPKMg and NPKCaMg treatments. In the very wettest year, the yields were dropped -43.1% on control soils, -39.3% of N, NP, or NK loadings and -35.8% on NPK, NPKCa, NPKMg and NPKCaMg treatments to those in the average year, reverse of Asbjorn et al. (2004). The relationships between rainfall quantitiy during the vegetation period N, P, K, Ca and Mg nutrition and yield were characterised by polynomial correlations (control: R= 0.7212***, N: R = 0.7410***, NP: R = 0.6452***, NK: R = 0.6998***, NPK: R = 0.5555***, NPKCa: R = 0.5578***, NPKMg: R = 0.4869**, NPKCaMg: R = 0.4341**). However, the total regression coefficients ranged from 0.43 to 0.74 in depence on the different nutrient application. Maximum yields of 5.8-6.0 t . ha-1 were achieved in the rainfall range of 580-620 mm. At values above and below this range the grain yield reduced quadratically. To sum up we can say climate change will gradually and, at some point, be even abruptly affects Europa and Hungary agriculture. Warming temperatures and a greather incidence and intensity of extreme weather events possible lead to significant reductions in triticale yield. Expanded ranges of crop agrochemicals and altered transmission dynamics of different irrigation solutions might exacarbate these reductions. Since farmers' strategies grow out of experience, they can find that the past will be a less reliable predictor of the future. 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