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Phytophthora root rot (PRR) of chickpea (Cicer arietinum) caused by Phytophthora medicaginis is an important disease. Partial resistance to PRR is sourced from Cicer echinospermum. In this study, we evaluated if lines with low levels of PRR foliage symptoms in two contrasting recombinant inbred line (RIL) populations parented by chickpea cultivars (Yorker and Rupali) and 04067-81-2-1-1 (C. echinospermum, interspecific breeding line) had a significant drag on yield parameters. For the Yorker × 04067-81-2-1-1 population with the highest level of PRR resistance, in the absence of PRR, low foliage symptom RIL had significantly later flowering and podding, lower grain yields, and lighter seed and shorter plant phenotypes than high foliage symptom RIL. A quantitative trait locus analysis identified significant QTL for flowering, height, 100-seed weight, and yield, and there was a significantly higher frequency of alleles for the negative agronomic traits (i.e., drag) from the 04067-81-2-1-1 parent in low foliage symptom RIL than in high foliage symptom RIL. For the Rupali × 04067-81-2-1-1 population with lower levels of PRR resistance, in the absence of PRR, low foliage symptom RIL had significantly lighter seed and shorter plants than high foliage symptom RIL. Significant QTL were detected, the majority were for the timing of flowering and podding (n = 18), others were for plant height, yield, and 100-seed weight. For this second population, the frequency of alleles for the negative agronomic traits from the 04067-81-2-1-1 parent did not differ between low and high foliage symptom RIL. The 100 seed weight of RIL under moderate PRR disease pressure showed some promise as a yield component trait to identify phenotypes with both high levels of PRR resistance and grain yield potential for further seed number evaluations. We identified that large population sizes are required to enable selection among chickpea × C. echinospermum crosses for high levels of PRR resistance without a significant drag on yield.

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Hundred-seed weight (HSW) and reproductive period length (RPL) are two major agronomic traits critical for soybean production and adaptation. However, both traits are quantitatively controlled by multiple genes that have yet to be comprehensively elucidated due to the lack of major genes; thereby, the genetic basis is largely unknown. In the present study, we conducted comprehensive genome-wide association analyses (GWAS) of HSW and RPL with multiple sets of accessions that were phenotyped across different environments. The large-scale analysis led to the identification of sixty-one and seventy-four significant QTLs for HSW and RPL, respectively. An ortholog-based search analysis prioritized the most promising candidate genes for the QTLs, including nine genes (TTG2, BZR1, BRI1, ANT, KLU, EOD1/BB, GPA1, ABA2, and ABI5) for HSW QTLs and nine genes (such as AGL8, AGL9, TOC1, and COL4) and six known soybean flowering time genes (E2, E3, E4, Tof11, Tof12, and FT2b) for RPL QTLs. We also demonstrated that some QTLs were targeted during domestication to drive the artificial selection of both traits towards human-favored traits. Local adaptation likely contributes to the increased genomic diversity of the QTLs underlying RPL. The results provide additional insight into the genetic basis of HSW and RPL and prioritize a valuable resource of candidate genes that merits further investigation to reveal the complex molecular mechanism and facilitate soybean improvement.

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Adzuki beans are widely cultivated in East Asia and are one of the earliest domesticated crops. In order to gain a deeper understanding of the genetic diversity and domestication history of adzuki beans, we conducted Genotyping by Sequencing (GBS) analysis on 366 landraces originating from Korea, China, and Japan, resulting in 6586 single-nucleotide polymorphisms (SNPs). Population structure analysis divided these 366 landraces into three subpopulations. These three subpopulations exhibited distinctive distributions, suggesting that they underwent extended domestication processes in their respective regions of origin. Phenotypic variance analysis of the three subpopulations indicated that the Korean-domesticated subpopulation exhibited significantly higher 100-seed weights, the Japanese-domesticated subpopulation showed significantly higher numbers of grains per pod, and the Chinese-domesticated subpopulation displayed significantly higher numbers of pods per plant. We speculate that these differences in yield-related traits may be attributed to varying emphases placed by early breeders in these regions on the selection of traits related to yield. A large number of genes related to biotic/abiotic stress resistance and defense were found in most quantitative trait locus (QTL) for yield-related traits using genome-wide association studies (GWAS). Genomic sliding window analysis of Tajima's D and a genetic differentiation coefficient (Fst) revealed distinct domestication selection signatures and genotype variations on these QTLs within each subpopulation. These findings indicate that each subpopulation would have been subjected to varied biotic/abiotic stress events in different origins, of which these stress events have caused balancing selection differences in the QTL of each subpopulation. In these balancing selections, plants tend to select genotypes with strong resistance under biotic/abiotic stress, but reduce the frequency of high-yield genotypes to varying degrees. These biotic/abiotic stressors impact crop yield and may even lead to selection purging, resulting in the loss of several high-yielding genotypes among landraces. However, this also fuels the flow of crop germplasms. Overall, balancing selection appears to have a more significant impact on the three yield-related traits compared to breeder-driven domestication selection. These findings are crucial for understanding the impact of domestication selection history on landraces and yield-related traits, aiding in the improvement of adzuki bean varieties.

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Chickpea is among the top three legumes produced and consumed worldwide. Early plant vigor, characterized by good germination and rapid seedling growth, is an important agronomic trait in many crops including chickpea, and shows a positive correlation with seed size. In this study, we report a gamma-ray-induced chickpea mutant with a larger organ and seed size. The mutant (elm) exhibits increased early vigor and contains higher proline that contributes to a better tolerance under salt stress at germination, seedling, and early vegetative phase. The trait is governed as monogenic recessive, with wild-type allele being incompletely dominant over the mutant. Genetic mapping of this locus (CaEl) identified it as a previously uncharacterized gene (101503252) in chromosome 1 of the chickpea genome. There is a deletion of this gene in the mutant with a complete loss of expression. In silico analysis suggests that the gene is present as a single copy in chickpea and related legumes of the galegoid clade. In the mutant, cell division and expansion are affected. Transcriptome profiling identified differentially regulated transcripts related to cell division, expansion, cell wall organization, and metabolism in the mutant. The mutant can be exploited in chickpea breeding programs for increasing plant vigor and seed size.

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Soybean (Glycine max) was domesticated from its wild relative Glycine soja. One-hundred-seed weight is one of the most important domesticated traits determining soybean yield; however, its underlying genetic basis remains elusive. We characterized a soybean seed size 1 (sss1) mutant featuring large seeds compared to its wild-type background. Positional cloning revealed that the candidate gene GmSSS1 encoded a SPINDLY homolog and was co-located in a well-identified quantitative trait locus (QTL)-rich region on chromosome 19. Knocking out GmSSS1 resulted in small seeds, while overexpressing GmSSS1/Gmsss1 induced large seeds. Modulating GmSSS1/Gmsss1 in transgenic plants can positively influence cell expansion and cell division. Relative to GmSSS1, one mutation leading to an E to Q substitution at the 182nd residue in Gmsss1 conferred an enhancing effect on seed weight. GmSSS1 underwent diversification in wild-type and cultivated soybean, and the alleles encoding the Gmsss1-type substitution of 182nd -Q, which originated along the central and downstream parts of the Yellow River, were selected and expanded during soybean domestication and improvement. We cloned the causative gene for the sss1 mutant, which is linked with a seed weight QTL, identified an elite allele of this gene for increasing seed weight, and provided new insights into soybean domestication and breeding.

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To address domestication and improvement studies of soybean seed size- and oil-related traits, a series of domesticated and improved regions, loci, and candidate genes were identified in 286 soybean accessions using domestication and improvement analyses, genome-wide association studies, quantitative trait locus (QTL) mapping and bulked segregant analyses in this study. As a result, 534 candidate domestication regions (CDRs) and 458 candidate improvement regions (CIRs) were identified in this study and integrated with those in five and three previous studies, respectively, to obtain 952 CDRs and 538 CIRs; 1469 loci for soybean seed size- and oil-related traits were identified in this study and integrated with those in Soybase to obtain 433 QTL clusters. The two results were intersected to obtain 245 domestication and 221 improvement loci for the above traits. Around these trait-related domestication and improvement loci, 7 domestication and 7 improvement genes were found to be truly associated with these traits, and 372 candidate domestication and 87 candidate improvement genes were identified using gene expression, SNP variants in genome, miRNA binding, KEGG pathway, DNA methylation, and haplotype analysis. These genes were used to explain the trait changes in domestication and improvement. As a result, the trait changes can be explained by their frequencies of elite haplotypes, base mutations in coding region, and three factors affecting their expression levels. In addition, 56 domestication and 15 improvement genes may be valuable for future soybean breeding. This study can provide useful gene resources for future soybean breeding and molecular biology research.

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In soybean [Glycine max (L.) Merrill], the genetic analysis of seed yield is important to aid in the breeding of high-yielding cultivars. Seed yield is a complex trait, and the number of quantitative trait loci (QTL) involved in seed yield is high. The aims of this study were to identify QTL associated with seed yield and validate their effects on seed yield using near-isogenic lines. The QTL analysis was conducted using a recombinant inbred line population derived from a cross between Japanese cultivars 'Toyoharuka' and 'Toyomusume', and eight seed yield-associated QTL were identified. There were significant positive correlations between seed yield and the number of favorable alleles at QTL associated with seed yield in the recombinant inbred lines for three years. The effects of qSY8-1, a QTL promoting greater seed yield, was validated in the Toyoharuka background. In a two-year yield trial, the 100-seed weight and seed yield of Toyoharuka-NIL, the near-isogenic line having the Toyomusume allele at qSY8-1, were significantly greater than those of Toyoharuka (106% and 107%, respectively) without any change for days to flowering and maturity. Our results suggest that qSY8-1 was not associated with maturity genes, and contributed to the 100-seed weight.

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Composting is a strategic technology to convert organic waste into environmentally friendly soil improvers, mitigating the pressure on landfills and contributing to sustainability. This research evaluates the effects of different doses of mineral/organic fertilizers on two chickpea types: desi and kabuli. A randomized block design with three replications and six conditions was adopted: non-fertilized control, two mineral fertilizations (M1, M2), and three organic fertilizations (B1, B2, B3). M1 and B1 provided for comparable NPK amounts. Fertilization and variety significantly influenced plant growth and production, and seed hydration. Fertilization had a lower influence on bioactive compounds. The highest seed yields were obtained with M2 (30-40-100 kg ha-1 of N, P2O5, and K2O, respectively. An addition of 40 kg ha-1 of P2O5 (M1) had no effect on seed yield. B1 (10 Mg ha-1 of Bio Vegetal) and M1 led to the same yield, which did not increase using higher doses of green compost. Mineral and organic fertilizations favored hydration and swelling of chickpeas. Desi chickpea showed a significantly higher seed yield but a lower seed weight than kabuli. Organic fertilization, combined with the recovery of peculiar chickpeas, which are more productive and richer in bioactive compounds, promotes a more sustainable food system.

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Globally terminal drought is one of the major constraints to chickpea (Cicer arietinum L.) production. Early flowering genotypes escape terminal drought, and the increase in seed size compensates for yield losses arising from terminal drought. A MutMap population for early flowering and large seed size was developed by crossing the mutant line ICC4958-M3-2828 with wild-type ICC 4958. Based on the phenotyping of MutMap population, extreme bulks for days to flowering and 100-seed weight were sequenced using Hi-Seq2500 at 10X coverage. On aligning 47.41 million filtered reads to the CDC Frontier reference genome, 31.41 million reads were mapped and 332,395 single nucleotide polymorphisms (SNPs) were called. A reference genome assembly for ICC 4958 was developed replacing these SNPs in particular positions of the CDC Frontier genome. SNPs specific for each mutant bulk ranged from 3,993 to 5,771. We report a single unique genomic region on Ca6 (between 9.76 and 12.96 Mb) harboring 31, 22, 17, and 32 SNPs with a peak of SNP index = 1 for low bulk for flowering time, high bulk for flowering time, high bulk for 100-seed weight, and low bulk for 100-seed weight, respectively. Among these, 22 SNPs are present in 20 candidate genes and had a moderate allelic impact on the genes. Two markers, Ca6EF10509893 for early flowering and Ca6HSDW10099486 for 100-seed weight, were developed and validated using the candidate SNPs. Thus, the associated genes, candidate SNPs, and markers developed in this study are useful for breeding chickpea varieties that mitigate yield losses under drought stress.

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BACKGROUND: Plant architecture-related traits (e.g., plant height (PH), number of nodes on main stem (NN), branch number (BN) and stem diameter (DI)) and 100-seed weight (100-SW) are important agronomic traits and are closely related to soybean yield. However, the genetic basis and breeding potential of these important agronomic traits remain largely ambiguous in soybean (Glycine max (L.) Merr.). RESULTS: In this study, we collected 133 soybean landraces from China, phenotyped them in two years at two locations for the above five traits and conducted a genome-wide association study (GWAS) using 82,187 single nucleotide polymorphisms (SNPs). As a result, we found that a total of 59 SNPs were repeatedly detected in at least two environments. There were 12, 12, 4, 4 and 27 SNPs associated with PH, NN, BN, DI and 100-SW, respectively. Among these markers, seven SNPs (AX-90380587, AX-90406013, AX-90387160, AX-90317160, AX-90449770, AX-90460927 and AX-90520043) were large-effect markers for PH, NN, BN, DI and 100-SW, and 15 potential candidate genes were predicted to be in linkage disequilibrium (LD) decay distance or LD block. In addition, real-time quantitative PCR (qRT-PCR) analysis was performed on four 100-SW potential candidate genes, three of them showed significantly different expression levels between the extreme materials at the seed development stage. Therefore, Glyma.05 g127900, Glyma.05 g128000 and Glyma.05 g129000 were considered as candidate genes with 100-SW in soybean. CONCLUSIONS: These findings shed light on the genetic basis of plant architecture-related traits and 100-SW in soybean, and candidate genes could be used for further positional cloning.

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As soybean plays an indispensable role in the supply of vegetable oil and protein, balancing the relationship between seed quality and yield traits according to human demand has become an important breeding goal for soybean improvement. Here, 256 intraspecific recombinant inbred lines (RILs), derived from a cross between Qi Huang No.34 (QH34) and Ji Dou No.17 (JD17), were used for quantitative trait loci (QTLs) mapping with remarkable four chemical and physical properties with a purpose for exploring the distribution of excellent alleles in germplasm resources in China. A total of 25 QTLs were detected, of which 10 QTLs inherited the alleles from the parent QH34. Pedigree research on favorable alleles on these QTLs showed the process of excellent alleles pyramided into QH34. Meta-analysis of the 25 QTLs by comparing with existed QTLs in previous study identified 17 novel QTLs. QTLs with pleiotropic effects have been detected. Furthermore, three representative elite recombinant inbred lines in different locations that have great potential in soybean breeding were selected, and finally, four seed weight-related candidate genes were identified. The discovery of these QTLs provides a new guidance for combining the diversity and rarity of germplasm resources, which can effectively increase population genetic diversity and broaden genetic basis of varieties. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01211-6.

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100-seed weight (100-SW) in soybeans is a yield component trait and controlled by multiple genes with different effects, but limited information is available for its quantitative trait nucleotides (QTNs) and candidate genes. To better understand the genetic architecture underlying the trait and improve the precision of marker-assisted selection, a total of 43,834 single nucleotide polymorphisms (SNPs) in 250 soybean accessions were used to identify significant QTNs for 100-SW in four environments and their BLUP values using six multi-locus and one single-locus genome-wide association study methods. As a result, a total of 218 significant QTNs were detected using multi-locus methods, whereas eight QTNs were identified by a single-locus method. Among 43 QTNs or QTN clusters identified repeatedly across various environments and/or approaches, all of them exhibited significant trait differences between their corresponding alleles, 33 were found in the genomic region of previously reported QTLs, 10 were identified as new QTNs, and three (qHSW-4-1, qcHSW-7-3, and qcHSW-10-4) were detected in all the four environments. The number of seed weight (SW) increasing alleles for each accession ranged from 8 (18.6%) to 36 (83.72%), and three accessions (Yixingwuhuangdou, Nannong 95C-5, and Yafanzaodou) had more than 35 SW increasing alleles. Among 36 homologous seed-weight genes in Arabidopsis underlying the above 43 stable QTNs, more importantly, Glyma05g34120, GmCRY1, and GmCPK11 had known seed-size/weight-related genes in soybean, and Glyma07g07850, Glyma10g03440, and Glyma10g36070 were candidate genes identified in this study. These results provide useful information for genetic foundation, marker-assisted selection, genomic prediction, and functional genomics of 100-SW.

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The 100-seed weight (100SW) is one of the most important traits that control soybean yield. To identify the quantitative trait loci (QTL) of 100SW, 120 BC3F5 chromosome segment substitution lines (CSSLs) were cultivated over three years. The CSSLs were developed from a cross between the cultivated soybean variety 'Jackson' and the wild soybean accession 'JWS156-1', followed by continuous backcrossing using 'Jackson' variety as a recurrent parent. A total of nine QTLs (qSW8.1, qSW9.1, qSW12.1, qSW13.1, qSW14.1, qSW16.1, qSW17.1, qSW17.2, and qSW20.1) were detected on eight chromosomes. Of these, qSW12.1 (LOD = 6.78-12.31) was detected over the three successive years on chromosome 12 as a novel, stable, and major QTL. To validate the effect of qSW12.1, a residual heterozygous line (RHL), RHL564, which showed heterozygous at the qSW12.1 region, was selected from the BC3F5 population. Of the two homologous genotypes in the progenies produced by self-pollination of RHL564, a higher seed weight was observed in the 'Jackson' genotype plants than that in the 'JWS156-1' genotype plants. qSW12.1 was delimited in an interval of approximately 1,348 kb between the BARCSOYSSR_12_1282 and BARCSOYSSR_12_1347 markers on chromosome 12.

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Deficiencies of iron (Fe) and zinc (Zn) are major problems in developing countries especially for woman and preschool children. Biofortification of staple food crops is a sustainable approach to improve human mineral intake via daily diet. Objectives of this study were to (1) determine the genetic variability for Fe and Zn content in cultivated indigenous and exotic lentil genotypes, and (2) determine the effect of genetic (G) × environmental (E) interaction on Fe and Zn content in 96 lentil genotypes grown in India over the 2 years. Significant genetic variability was observed for Fe and Zn content in lentil genotypes. Content ranged from 71.3 to 126.2 mg/kg for Fe, and 40.1 to 63.6 mg/kg for Zn. For Fe, cultivars and parental lines (71.3-126.2 mg/kg) showed slightly higher content than the breeding lines (76.8-124.3 mg/kg). For Zn, content were similar for both cultivars and breeding lines. However, year and the genotype × year interaction were significant for both Fe and Zn. Broad sense heritability estimates were found to be 45.8, 45.4 and 40.1 for Fe; 30.0, 63.0 and 69.0 for Zn content in breeding lines, cultivars/parental lines, and exotic lines, respectively. These heritability estimates indicated the potential of these lentil genotypes towards genetic improvement for increased Fe and Zn content using hybridization and selection over several generations. Significant positive correlation of Fe content and seed weight suggested a selection strategy for developing large seeded lentil for accumulation of more Fe in the seeds. No correlation was observed between Fe and Zn content. Further, recombination of Fe and Zn content is possible by developing recombination breeding. Thus present study findings would be useful in future for mapping and tagging the genes/QTL controlling Fe and Zn content and developing the improved biofortified cultivars.

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BACKGROUND: To continue to meet the increasing demands of soybean worldwide, it is crucial to identify key genes regulating flowering and maturity to expand the cultivated regions into short season areas. Although four soybean genes have been successfully utilized in early maturity breeding programs, new genes governing maturity are continuously being identified suggesting that there remains as yet undiscovered loci governing agronomic traits of interest. The objective of this study was to identify novel loci and genes involved in a diverse set of early soybean maturity using genome-wide association (GWA) analyses to identify loci governing days to maturity (DTM), flowering (DTF) and pod filling (DTPF), as well as yield and 100 seed weight in Canadian environments. To do so, soybean plant introduction lines varying significantly for maturity, but classified as early varieties, were used. Plants were phenotyped for the five agronomic traits for five site-years and GWA approaches used to identify candidate loci and genes affecting each trait. RESULTS: Genotyping using genotyping-by-sequencing and microarray methods identified 67,594 single nucleotide polymorphisms, of which 31,283 had a linkage disequilibrium < 1 and minor allele frequency > 0.05 and were used for GWA analyses. A total of 9, 6, 4, 5 and 2 loci were detected for GWA analyses for DTM, DTF, DTPF, 100 seed weight and yield, respectively. Regions of interest, including a region surrounding the E1 gene for flowering and maturity, and several novel loci, were identified, with several loci having pleiotropic effects. Novel loci affecting maturity were identified on chromosomes five and 13 and reduced maturity by 7.2 and 3.3 days, respectively. Novel loci for maturity and flowering contained genes orthologous to known Arabidopsis flowering genes, while loci affecting yield and 100 seed weight contained genes known to cause dwarfism. CONCLUSIONS: This study demonstrated substantial variation in soybean agronomic traits of interest, including maturity and flowering dates as well as yield, and the utility of GWA analyses in identifying novel genetic factors underlying important agronomic traits. The loci and candidate genes identified serve as promising targets for future studies examining the mechanisms underlying the related soybean traits.

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Cultivated soybeans may lose some useful genetic loci during domestication. Introgression of genes from wild soybeans could broaden the genetic background and improve soybean agronomic traits. In this study, through whole-genome sequencing of a recombinant inbred line population derived from a cross between a wild soybean ZYD7 and a cultivated soybean HN44, and mapping of quantitative trait loci for seed weight, we discovered that a phosphatase 2C-1 (PP2C-1) allele from wild soybean ZYD7 contributes to the increase in seed weight/size. PP2C-1 may achieve this function by enhancing cell size of integument and activating a subset of seed trait-related genes. We found that PP2C-1 is associated with GmBZR1, a soybean ortholog of Arabidopsis BZR1, one of key transcription factors in brassinosteroid (BR) signaling, and facilitate accumulation of dephosphorylated GmBZR1. In contrast, the PP2C-2 allele with variations of a few amino acids at the N-terminus did not exhibit this function. Moreover, we showed that GmBZR1 could promote seed weight/size in transgenic plants. Through analysis of cultivated soybean accessions, we found that 40% of the examined accessions do not have the PP2C-1 allele, suggesting that these accessions can be improved by introduction of this allele. Taken together, our study identifies an elite allele PP2C-1, which can enhance seed weight and/or size in soybean, and pinpoints that manipulation of this allele by molecular-assisted breeding may increase production in soybean and other legumes/crops.

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A representative sample comprising 366 accessions from the Chinese soybean landrace population (CSLRP) was tested under four growth environments for determination of the whole-genome quantitative trait loci (QTLs) system of the 100-seed weight trait (ranging from 4.59g to 40.35g) through genome-wide association study (GWAS). A total of 116 769 single nucleotide polymorphisms (SNPs) were identified and organized into 29 121 SNP linkage disequilibrium blocks (SNPLDBs) to fit the property of multiple alleles/haplotypes per locus in germplasm. An innovative two-stage GWAS was conducted using a single locus model for shrinking the marker number followed by a multiple loci model utilizing a stepwise regression for the whole-genome QTL identification. In total, 98.45% of the phenotypic variance (PV) was accounted for by four large-contribution major QTLs (36.33%), 51 small-contribution major QTLs (43.24%), and a number of unmapped minor QTLs (18.88%), with the QTL×environment variance representing only 1.01% of the PV. The allele numbers of each QTL ranged from two to 10. A total of 263 alleles along with the respective allele effects were estimated and organized into a 263×366 matrix, giving the compact genetic constitution of the CSLRP. Differentiations among the ecoregion matrices were found. No landrace had alleles which were all positive or all negative, indicating a hidden potential for recombination. The optimal crosses within and among ecoregions were predicted, and showed great transgressive potential. From the QTL system, 39 candidate genes were annotated, of which 26 were involved with the gene ontology categories of biological process, cellular component, and molecular function, indicating that diverse genes are involved in directing the 100-seed weight.

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Foram conduzidos três ensaios em município de Minas Gerais, com inverno ameno, para estudar a viabilidade do cultivo do feijão-arroz no outono-inverno. Os ensaios foram instalados em Leopoldina, nestas datas: 3 de maio de 1996, 18 de abril de 1997 e 11 de maio de 1998. Foram usados 12 genótipos de feijão-arroz; uma cultivar de feijão-comum foi usada para comparação. Foi empregado o delineamento em blocos ao acaso, com 4 repetições. As plantas foram irrigadas por aspersão, e o controle de pragas com inseticida foi feito quando necessário. Os ciclos de vida do feijão-arroz variaram de 99 a 111 dias (da emergência à colheita), enquanto os do feijão-comum variaram em torno de 90 dias. Não foi observada doença na folhagem do feijão-arroz. As produtividades médias variaram de 1164 (11 de maio) a 2261 kg ha-1 (18 de abril). O feijão-arroz foi tão produtivo quanto o feijão-comum. Conclui-se que é viável o cultivo do feijão-arroz [Vigna umbellata (Thunb.) Ohwi & Ohashi] no outono-inverno em regiões de inverno ameno.

Three trials were carried out in a municipality of the state of Minas Gerais of mild winter to study the viability of rice bean cultivation in fall-winter season. Trials were installed in Leopoldina on the following dates: May 3, 1996; April 18, 1997; and May 11, 1998. Twelve genotypes of rice bean were used; one cultivar of common bean was also included for comparison. A randomized complete-block design with 4 replications was used. Plants were sprinkler irrigated and insecticide was applied when necessary. Rice bean life cycles varied from 99 to 111 days (from emergence to harvest), while common bean life cycles varied around 90 days. No foliar disease was observed on rice bean plants. Yields ranged from 1164 (May 11) to 2261 kg ha-1 (April 18). Rice bean yielded as much as common bean. One concluded that the cultivation of rice bean [Vigna umbellata (Thunb.) Ohwi & Ohashi] in fall-winter in regions of mild winter is viable.