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Abstract: Quantitative trait loci (QTLs) contributing to yellow seed colour and acid detergent fibre (ADF) were localized and compared in 3 mapping populations developed from 2 crosses (designated 'YE1' and [...]

Rapeseed meal, a by-product of oilseed extraction related to the agri-food and biofuel industries due to its favourable composition of essential amino acids, is currently utilised for animal feed. In this study, 166 doubled haploid (DH) rapeseed lines from the segregating Brassica napus doubled haploid population YE2-DH were genetically and chemically analysed for phenolic acids. The relationship between seed colour and phenolic acid fractions in B. napus was investigated using these analyses to improve the quality of rapeseed meal. High-performance liquid chromatography assays were used to estimate phenolic acid content, and the outcomes were used to identify quantitative trait loci (QTL). Nine quantitative feature loci for three distinct phenolic acid compounds were mapped to seven linkage groups. A minor QTL for sinapine was located on linkage group C05 in the same interval as the QTL for seed colour. On chromosome A09, two loci for phenolic acids colocalised with the main QTL for seed colour. Closely linked molecular markers for the target traits (seed colour, phenolic acids) identified during this study could be useful tools for breeding new oilseed rape cultivars with lower levels of antinutritive compounds. [ABSTRACT FROM AUTHOR]

Abstract Background Fusarium head blight (FHB) caused by Fusarium species like F. graminearum is a devastating disease of wheat (Triticum aestivum) worldwide. Mycotoxins such as deoxynivalenol produced by the fungus affect plant and animal health, and cause significant reductions of grain yield and quality. Resistant varieties are the only effective way to control this disease, but the molecular events leading to FHB resistance are still poorly understood. Transcriptional profiling was conducted for the winter wheat cultivars Dream (moderately resistant) and Lynx (susceptible). The gene expressions at 32 and 72 h after inoculation with Fusarium were used to trace possible defence mechanisms and associated genes. A comparative qPCR was carried out for selected genes to analyse the respective expression patterns in the resistant cultivars Dream and Sumai 3 (Chinese spring wheat). Results Among 2,169 differentially expressed genes, two putative main defence mechanisms were found in the FHB-resistant Dream cultivar. Both are defined base on their specific mode of resistance. A non-specific mechanism was based on several defence genes probably induced by jasmonate and ethylene signalling, including lipid-transfer protein, thionin, defensin and GDSL-like lipase genes. Additionally, defence-related genes encoding jasmonate-regulated proteins were up-regulated in response to FHB. Another mechanism based on the targeted suppression of essential Fusarium virulence factors comprising proteases and mycotoxins was found to be an essential, induced defence of general relevance in wheat. Moreover, similar inductions upon fungal infection were frequently observed among FHB-responsive genes of both mechanisms in the cultivars Dream and Sumai 3. Conclusions Especially ABC transporter, UDP-glucosyltransferase, protease and protease inhibitor genes associated with the defence mechanism against fungal virulence factors are apparently active in different resistant genetic backgrounds, according to reports on other wheat cultivars and barley. This was further supported in our qPCR experiments on seven genes originating from this mechanism which revealed similar activities in the resistant cultivars Dream and Sumai 3. Finally, the combination of early-stage and steady-state induction was associated with resistance, while transcript induction generally occurred later and temporarily in the susceptible cultivars. The respective mechanisms are attractive for advanced studies aiming at new resistance and toxin management strategies.

Abstract Background Serial analysis of gene expression (LongSAGE) was applied for gene expression profiling in seeds of oilseed rape (Brassica napus ssp. napus). The usefulness of this technique for detailed expression profiling in a non-model organism was demonstrated for the highly complex, neither fully sequenced nor annotated genome of B. napus by applying a tag-to-gene matching strategy based on Brassica ESTs and the annotated proteome of the closely related model crucifer A. thaliana. Results Transcripts from 3,094 genes were detected at two time-points of seed development, 23 days and 35 days after pollination (DAP). Differential expression showed a shift from gene expression involved in diverse developmental processes including cell proliferation and seed coat formation at 23 DAP to more focussed metabolic processes including storage protein accumulation and lipid deposition at 35 DAP. The most abundant transcripts at 23 DAP were coding for diverse protease inhibitor proteins and proteases, including cysteine proteases involved in seed coat formation and a number of lipid transfer proteins involved in embryo pattern formation. At 35 DAP, transcripts encoding napin, cruciferin and oleosin storage proteins were most abundant. Over both time-points, 18.6% of the detected genes were matched by Brassica ESTs identified by LongSAGE tags in antisense orientation. This suggests a strong involvement of antisense transcript expression in regulatory processes during B. napus seed development. Conclusion This study underlines the potential of transcript tagging approaches for gene expression profiling in Brassica crop species via EST matching to annotated A. thaliana genes. Limits of tag detection for low-abundance transcripts can today be overcome by ultra-high throughput sequencing approaches, so that tag-based gene expression profiling may soon become the method of choice for global expression profiling in non-model species.

The extent of phenotypic variation among Sesame germplasm influences the expression of economic traits and the response to selection. The objective of this study was to determine the variance components, heritability (H2) and association of seed and oil yield‐related traits in Ethiopian sesame germplasm to guide breeding. One hundred sesame germplasm were evaluated under field conditions in two locations in a 10 x 10 lattice design with two replications. The findings revealed higher genotypic coefficient of variation, H2, and genetic advance for number of primary branches (NPB), number of secondary branches (NSB), thousand seed weight (TSW), seed yield per hectare (SYH) and oil yield per hectare (OYH), suggesting high genetic gains can be achieved through selection. Higher direct effects of OYH and NSPC were recorded on SYH, while SYH, NCPP and TSW had higher direct effect on OYH. The genotypes Hirhir Kebabo Hairless‐9, Setit‐3, Orofalc ACC‐2, Hirhir Humera Sel‐6, Setit‐1 and ACC‐NS‐007(2) were found superior and the selected genotypes should promote for further field stability evaluation, which might be utilized in future sesame breeding programmes and production. [ABSTRACT FROM AUTHOR]

The use of rutabaga for increasing the level of heterosis in spring canola was investigated. For this, test hybrids were produced by crossing four inbred populations, derived from F2 and BC1 of two rutabaga × spring canola crosses, to their spring canola parent, and were tested in field‐plots for agronomic and seed quality traits. Average mid‐parent heterosis (MPH) in these test hybrid populations was about 5%‐15% for yield. Compared to the F2‐derived population, the BC1‐derived population exhibited 1.8‐times greater MPH for yield. No correlation was found between inbred and test hybrid for yield; however, a positive correlation of genetic diversity of the inbred lines was found with MPH (r =.58) and hybrid yield (r =.36) suggesting that non‐additive effect of the genes may play an important role for high yield in hybrids. About 2% negative MPH was found for days to flowering, while almost no heterosis was found for seed oil and protein contents. Thus, our study demonstrates the potential of the rutabaga gene pool for use in hybrid canola breeding. [ABSTRACT FROM AUTHOR]

Doubled haploids (DHs) are an important breeding tool for creating maize inbred lines. One bottleneck in the DH process is the manual separation of haploids from among the much larger pool of hybrid siblings in a haploid induction cross. Here, we demonstrate the ability of single‐kernel near‐infrared reflectance spectroscopy (skNIR) to identify haploid kernels. The skNIR is a high‐throughput device that acquires an NIR spectrum to predict individual kernel traits. We collected skNIR data from haploid and hybrid kernels in 15 haploid induction crosses and found significant differences in multiple traits such as percent oil, seed weight, or volume, within each cross. The two kernel classes were separated by their NIR profile using Partial Least Squares Linear Discriminant Analysis (PLS‐LDA). A general classification model, in which all induction crosses were used in the discrimination model, and a specific model, in which only kernels within a specific induction cross, were compared. Specific models outperformed the general model and were able to enrich a haploid selection pool to above 50% haploids. Applications for the instrument are discussed. [ABSTRACT FROM AUTHOR]

Since wheat and other annual cereal crops are often harvested for forage instead of grain in California, replacing them with perennial crops could save energy and reduce the release of heat‐trapping gases. To assess the potential for perennial crops based on wheat, biomass yield and stand persistence were studied for nine wheat×wheatgrass amphiploids (8x to 14x) and five wheatgrass species (2x to 10x) over three seasons in the Central Valley, California. The 8x and 10x amphiploids died after one biomass harvest and a single summer period. In contrast, the 14x amphiploids, which were sterile, continued producing biomass over the entire period of the trial. They were also highly salt‐stress tolerant with little decline in biomass production in response to an increase in salinity from 100 and 250 mM NaCl in a solution‐culture study. The development of a salt‐stress‐tolerant perennial crop based on wheat for the California‐type climate will require either a substantial improvement in perennial growth of low‐ploidy (8x) amphiploids or the development of technology for efficient vegetative propagation of the sterile high‐ploidy (14x) amphiploids. [ABSTRACT FROM AUTHOR]

Alternaria leaf spot (ALS) caused by Alternaria carthami Chowdhury can cause yield loss up to 90% in safflower (Carthamus tinctorius L.) under severe conditions. Even though a definite source of ALS resistance is not available in cultivated species, a few of the wild species, viz. C. palaestinus and C. lantaus, are known to be tolerant to ALS. Therefore, an attempt was made to introgress Alternaria resistance from these species into cultivated species. F1‐F8 generations of crosses (PI537632 × C. palaestinus), (C. palaestinus × PI537632), ("Nira" × C. palaestinus) and ([MS 6(O) × C. lanatus] × C. palaestinus) were screened against ALS. ALS infection (%) was recorded in field and quantified using Windias Leaf Image Analysis system. Detached leaf technique was used in laboratory to confirm resistance in interspecific selections. Six resistant and 29 moderately resistant interspecific lines resembling mostly cultivated species were developed. Inheritance of ALS resistance indicated involvement of multiple minor alleles having small effects on resistance. The identified resistant lines could provide potential source of resistance to ALS for safflower breeding programmes. [ABSTRACT FROM AUTHOR]