Qtls Controlling Seed Weight and Days to Flowering in Mungbean [Vigna Radiata (L.) Wilczek], Their Conservation in Azuki Bean [V. Angularis (Ohwi) Ohwi & Ohashi] and Rice Bean [V. Umbellata (Thunb.) Ohwi & Ohashi]

Mungbean (Vigna radiata (L.) Wilczek) is a socio-economically important legume crop of Asia. Varieties with large seed size and early maturity are preferred in commercial production. In this study, we identified quantitative trait loci (QTL) controlling seed weight and days to flowering in mungbean. The mapping population comprises 155 F2-derived lines from a cross between Kamphaeng Saen 1 (large-seeded and early flowering) and V4718 (small-seeded and late flowering). The F2 population was analyzed with 67 simple sequence repeat markers. The F2:3 families were evaluated for 100-seed weigh and days to flowering in two years, 2008 (one season) and 2011 (two seasons). Composite interval mapping identified six QTLs for 100-seed weight and 5 QTLs for days to flowering. Three genomic regions harbored QTLs for both seed weight and days to flowering, revealing association between the two traits. Comparison of QTLs for both traits found in this study with those reported in azuki bean (Vigna angularis (Willd.) Ohwi & Ohashi) and rice bean (Vigna umbellata (Thunb.) Ohwi & Ohashi) revealed that several QTLs are conserved among the three Vigna species

Genome sequence of Jatropha curcas L., a non-edible biodiesel plant, provides a resource to improve seed-related traits

Jatropha curcas (physic nut), a non‐edible oilseed crop, represents one of the most promising alternative energy sources due to its high seed oil content, rapid growth and adaptability to various environments. We report ~339 Mbp draft whole genome sequence of J. curcas var. Chai Nat using both the PacBio and Illumina sequencing platforms. We identified and categorized differentially expressed genes related to biosynthesis of lipid and toxic compound among four stages of seed development. Triacylglycerol (TAG), the major component of seed storage oil, is mainly synthesized by phospholipid:diacylglycerol acyltransferase in Jatropha, and continuous high expression of homologs of oleosin over seed development contributes to accumulation of high level of oil in kernels by preventing the breakdown of TAG. A physical cluster of genes for diterpenoid biosynthetic enzymes, including casbene synthases highly responsible for a toxic compound, phorbol ester, in seed cake, was syntenically highly conserved between Jatropha and castor bean. Transcriptomic analysis of female and male flowers revealed the up‐regulation of a dozen family of TFs in female flower. Additionally, we constructed a robust species tree enabling estimation of divergence times among nine Jatropha species and five commercial crops in Malpighiales order. Our results will help researchers and breeders increase energy efficiency of this important oil seed crop by improving yield and oil content, and eliminating toxic compound in seed cake for animal feed

Genome sequence of mungbean and insights into evolution within Vigna species

Mungbean (Vigna radiata) is a fast-growing, warm-season legume crop that is primarily cultivated in developing countries of Asia. Here we construct a draft genome sequence of mungbean to facilitate genome research into the subgenus Ceratotropis, which includes several important dietary legumes in Asia, and to enable a better understanding of the evolution of leguminous species. Based on the de novo assembly of additional wild mungbean species, the divergence of what was eventually domesticated and the sampled wild mungbean species appears to have predated domestication. Moreover, the de novo assembly of a tetraploid Vigna species (V. reflexo-pilosa var. glabra) provides genomic evidence of a recent allopolyploid event. The species tree is constructed using de novo RNA-seq assemblies of 22 accessions of 18 Vigna species and protein sets of Glycine max. The present assembly of V. radiata var. radiata will facilitate genome research and accelerate molecular breeding of the subgenus Ceratotropis

Genome sequence of mungbean and insights into evolution within Vigna species

Mungbean (Vigna radiata) is a fast-growing, warm-season legume crop that is primarily cultivated in developing countries of Asia. Here we construct a draft genome sequence of mungbean to facilitate genome research into the subgenus Ceratotropis, which includes several important dietary legumes in Asia, and to enable a better understanding of the evolution of leguminous species. Based on the de novo assembly of additional wild mungbean species, the divergence of what was eventually domesticated and the sampled wild mungbean species appears to have predated domestication. Moreover, the de novo assembly of a tetraploid Vigna species (V. reflexo-pilosa var. glabra) provides genomic evidence of a recent allopolyploid event. The species tree is constructed using de novo RNA-seq assemblies of 22 accessions of 18 Vigna species and protein sets of Glycine max. The present assembly of V. radiata var. radiata will facilitate genome research and accelerate molecular breeding of the subgenus Ceratotropis

Removal of lead from contaminated soils by Typha angustifolia

A greenhouse study was demonstrated for removal of lead (Pb) from contaminated soil by the narrow — leaved cattail, Typha angustifolia. The plants were grown in sandy loam soil containing various concentrations of Pb(NO3)2 (53.3, 106.7, 160, 213.3, and 266.7 mg Pb kg-1 soil). Most lead was accumulated in roots and then transported to leaves. In soil contaminated with 266.7 mg kg-1 of lead, the plants accumulated 7492.6 mg Pb kg-1 dry weight in the roots and 167 mg Pb kg-1 dry weight in the leaves. Yet, no growth retardation from lead was detected. T. angustifolia has high potential as a plant to clean up lead contaminated soil due to its vigorous growth, high biomass productivity, and because it is a perennial in nature. Further work is required to study on the iron plaque formation and its role in metal immobilization

Evaluation of wheat mutants for thermo-stability through physiological parameters

Photosynthetic activity performance of 3 wheat mutants such as BG48-3-1, BG48-3-7, and BD29-3-9 were studied at 2 different levels of temperature (20 °C and 30 °C) at seedling stage under controlled environment conditions during 2011 at Rothamsted Research, UK. These mutants had earlier been developed from 'Cham1' by exposing germinating seeds to the chemical mutagen, ethyl methane sulphonate (EMS). Simple mutations affecting amino acid residues close to catalytically important regions of Rubisco Activase in these mutants were identified through TILLING (Targeting Induced Local Lesions in Genomes). Although generally the mutants were less active for photosynthetic activity (A) than 'Cham1' (control) at 20 °C but their A exceeded those of the control at every CO2 concentration and photosynthetic photon flux density (PPFD) tested at 30 °C. The higher A of the mutant lines at 30 °C was correlated with the induction of mutations affecting amino acid residues close to catalytically important regions of Rubisco activase. Differing trends in leaf stomatal conductance (gs) were observed for mutants and parent lines at 20 °C and 30 °C. Among the mutants, those with gs below 0.54 mmol m-2 s-1 at 20 °C showed greater gs at 30 °C; while the mutants exceeding the gs above 0.54 mmol m-2 s-1 at 20 °C showed slightly lower gs at 30 °C. In Cham1, however, the gs was invariably higher at 30 °C than 20 °C. Intercellular CO2 (Ci) was slightly lower in all mutant lines at every CO2 concentration and at all light intensities. Ci was also slightly lower in mutants at lowest light intensities at 20 than 30 °C. In contrast, Cham1 showed modest increase in Ci at 30 °C. Mutant BG48-3-1 at 30 °C displayed the highest rates of transpiration (E), while Cham1 and mutant BG48-3-7 at 20 °C displayed the highest E. The results are consistent with Rubisco activase from the mutant lines possessing greater thermal-stability than parent 'Cham1' at 30 °C under different levels of CO2 and PPFD. However, the mutant lines require more thorough evaluation before recommendation as a source of germplasm with enhanced thermal tolerance for use in wheat breeding programs