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Mungbean [Vigna radiata (L.) R. Wilczek] is an agro‐economically important legume crop of Thailand. In recent years, mungbean has been gaining attention and popularity from consumers and industries for its dense nutrients. Although farmers, consumers, and processors prefer large‐seeded mungbeans, all mungbean cultivars available in Thailand are medium‐seeded. Therefore, a need was felt to develop new mungbean cultivars with large seed size that would fulfill the needs of farmers, consumers, and processors. In this study, we report the development of two new mungbean cultivars: 'KUML4' (Reg. no. CV‐354, PI 703288) and 'KUML8' (Reg. no. CV‐355, PI 703289). These cultivars were developed by pedigree and bulk‐selection methods. Standard yield trials revealed that KUML4 gave seed yields (SDY) of 1444.75 and 1316.38 kg ha−1, respectively, which was on par with check cultivars. The seed of KUML4 and KUML8 was larger than all of the check cultivars; their 100‐seed weights were 7.25 and 7.84 g, respectively, compared with 6.58 g, the mean of the check cultivars. Further, the genotype main effect plus genotype‐by‐environment analysis showed that KUML4 had good yield stability for its SDY. The yield trials under farmer fields and practices revealed that KUML4 gave SDY similar to the best check cultivar, 'Chai Nat 3' (CN3), whereas KUML8 gave a lower yield than CN3. The yield gap between the experimental research station and farmer field/practice was about 47%. In conclusion, KUML4 and KUML8 have shown high yield, large seed size, and early and uniform maturity. Core Ideas: Two mungbean cultivars with large seeds and high yield stability were developed for Thailand.The seed size of both cultivars is greater than that of all other cultivars.These large‐seeded cultivars will be preferred by farmers, traders, consumers, and processors. [ABSTRACT FROM AUTHOR]

Black gram (Vigna mungo) is an important short duration grain legume crop. Black gram seeds provide an inexpensive source of dietary protein. Here, we applied the 10X Genomics linked‐read technology to obtain a de novo whole genome assembly of V. mungo cultivated variety Chai Nat 80 (CN80). The preliminary assembly contained 12,228 contigs and had an N50 length of 5.2 Mb. Subsequent scaffolding using the long‐range Chicago and HiC techniques yielded the first high‐quality, chromosome‐level assembly of 499 Mb comprising 11 pseudomolecules. Comparative genomics analyses based on sequence information from single‐copy orthologous genes revealed that black gram and mungbean (Vigna radiata) diverged about 2.7 million years ago. The transversion rate (4DTv) analysis in V. mungo revealed no evidence supporting a recent genome‐wide duplication event observed in the tetraploid créole bean (Vigna reflexo‐pilosa). The proportion of repetitive elements in the black gram genome is slightly lower than the numbers reported for related Vigna species. The majority of long terminal repeat retrotransposons appeared to integrate into the genome within the last five million years. We also examined alternative splicing events in V. mungo using full‐length transcript sequences. While intron retention was the most prevalent mode of alternative splicing in several plant species, alternative 3' acceptor site selection represented the majority of events in black gram. Our high‐quality genome assembly along with the genomic variation information from the germplasm provides valuable resources for accelerating the development of elite varieties through marker‐assisted breeding and for future comparative genomics and phylogenetic studies in legume species. [ABSTRACT FROM AUTHOR]

Summary: 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. [ABSTRACT FROM AUTHOR]