Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
291 result(s) for "pod traits"
Sort by:
A High Density Genetic Map Derived from RAD Sequencing and Its Application in QTL Analysis of Yield-Related Traits in Vigna unguiculata
Cowpea [ (L.) Walp.] is an annual legume of economic importance and widely grown in the semi-arid tropics. However, high-density genetic maps of cowpea are still lacking. Here, we identified 34,868 SNPs (single nucleotide polymorphisms) that were distributed in the cowpea genome based on the RAD sequencing (restriction-site associated DNA sequencing) technique using a population of 170 individuals (two cowpea parents and 168 F progenies). Of these, 17,996 reliable SNPs were allotted to 11 consensus linkage groups (LGs). The length of the genetic map was 1,194.25 cM in total with a mean distance of 0.066 cM/SNP marker locus. Using this map and the F population, combined with the CIM (composite interval mapping) method, eleven quantitative trait loci (QTL) of yield-related trait were detected on seven LGs (LG4, 5, 6, 7, 9, 10, and 11) in cowpea. These QTL explained 0.05-17.32% of the total phenotypic variation. Among these, four QTL were for pod length, four QTL for thousand-grain weight (TGW), two QTL for grain number per pod, and one QTL for carpopodium length. Our results will provide a foundation for understanding genes related to grain yield in the cowpea and genus .
Estimates of genotypic and phenotypic variance, heritability, and genetic advance of horticultural traits in developed crosses of cowpea (Vigna unguiculata L. Walp)
Cowpea, in addition to being a food and feed crop, plays a key role in sustainable farming. The present study’s goal is to develop new high-yielding cowpea varieties. A Field experiment was carried out across 3 summer seasons and the breeding program included 28 distinct cowpea varieties, out of which five potential parents were selected for this investigation. Local cultivars, i.e., Cream 7 ‘Cr7’, Dokki 331 ‘D331’, Commercial 1 ‘Com1’, and introduced cultivars, i.e., Colossus ‘Col’ and Asian Introduction ‘AI’ were utilized to produce six crosses in two generations apart; F 1 and F 2 : Col x AI, Col x Com1, Cr7 x AI, Cr7 x Com1, D331 x AI, and D331 x Com1. ‘AI’ and ‘Com1’ were superior in pod length, pod diameter, number of seeds/pod and seeds weight/pod, whereas ‘Col’, ‘Cr7’ and ‘D331’ were superior in seeds yield/plant, number of pods/plant and the least number of aborted ovules/pod. The genotypes/crosses showed greater genotypic variance (GV) than phenotypic variance (PV) for number of pods/plant, pod length, number of seeds/pod, number of aborted ovules/pod, fresh pod weight, seeds weight/pod, and seeds yield/plant. All studied variables showed high heritability (H%) in genotypes/crosses, despite the exception of seeds weight/pod, which ranged from 29.14 in ‘D331’ to 83.7 in F 2 of Col x Com1. F 2 plants and their parents’ genotypes showed greater H%. Cr7 x AI developed the most H%, 99.04% for number of pods/plant. D331 x Com1 and Cr7 x AI exhibited moderate H% for fresh pod weight in F 1 , but all other crosses had high H%. F 1 and F 2 crosses yielded moderate to high GCV and PCV for number of seeds/pod. Variations in parental genotypes and crossings reflect genetic diversity and the possibility of selection. Crossing with ‘AI,’ and ‘Com1’ genotypes enhanced the performance of the other varieties, ‘Col’, ‘D331’ and ‘Cr7’. Cr7 x Com1 and D331 x AI were selected as the most promising crosses for cowpea breeding programs.
Genome wide association mapping and candidate gene analysis for pod shatter resistance in Brassica juncea and its progenitor species
We investigated phenotypic variations for pod shattering, pod length and number of seeds per pod in large germplasm collections of Brassica juncea (2n = 36; AABB) and its progenitor species, B. rapa (2n = 20; AA) and B. nigra (2n = 16; BB). Pod shatter resistance was measured as energy required for rupturing a mature dry pod, with a specially fabricated pendulum machine. Rupture energy (RE) ranged from 3.3 to 11.0 mJ in B. juncea . MCP 633, NR 3350 and Albeli required maximum energy to shatter a pod. It ranged from 2.5 to 7.8 mJ for B. rapa with an average of 5.5 mJ. B. nigra possessed easy to rupture pods. Correlation analysis showed strong associations among these traits in B. juncea and B. rapa. Genome wide association studies were conducted with select sets of B. juncea and B. rapa germplasm lines. Significant and annotated associations predict the role of FRUITFULL, MANNASE7, and NAC secondary wall thickening promoting factor ( NST2 ) in the genetic regulation of shatter resistance in B. juncea . NST2 and SHP1 appeared important for pod length and seeds per pod in B. rapa . Candidate gene based association mapping also confirmed the role of SHP1 and NST2 in regulating pod shattering and related pod traits in B. rapa and B. juncea . Footprints of selection were detected in SHP1 , SHP2 ( B. rapa , B. nigra and B. juncea ), RPL ( B. rapa ) and NAC ( B. juncea ). Our results provide insights into the genetic architecture of three pod traits. The identified genes are relevant to improving and securing crop productivity of mustard crop.
A Core Set of Snap Bean Genotypes Established by Phenotyping a Large Panel Collected in Europe
Snap beans are a group of bean cultivars grown for their edible immature pods. The objective of this work was to characterize the diversity of pod phenotypes in a snap bean panel (SBP), comprising 311 lines collected in Europe, and establish a core set (Core-SBP) with the maximum diversity of pod phenotypes. Phenotyping of the SBP was carried out over two seasons based on 14 quantitative pod dimension traits along with three qualitative traits: pod color, seed coat color, and growth habit. Phenotypes were grouped into 54 classes using a hierarchical method, and a Core-SBP with one line per phenotype class was established. A further field-based evaluation of the Core-SBP revealed higher diversity index values than those obtained for the SBP. The Core-SBP was also genotyped using 24 breeder-friendly DNA markers tagging 21 genomic regions previously associated with pod trait control. Significant marker-trait associations were found for 11 of the 21 analyzed regions as well as the locus fin. The established Core-SBP was a first attempt to classify snap bean cultivars based on pod morphology and constituted a valuable source of characteristics for future breeding programs and genetic analysis.
Identification of QTLs for seed and pod traits in soybean and analysis for additive effects and epistatic effects of QTLs among multiple environments
Soybean seed and pod traits are important yield components. Selection for high yield style in seed and pod along with agronomic traits is a goal of many soybean breeders. The intention of this study was to identify quantitative trait loci (QTL) underlying seed and pod traits in soybean among eleven environments in China. 147 recombinant inbred lines were advanced through single-seed-descent method. The population was derived from a cross between Charleston (an American high yield soybean cultivar) and DongNong594 (a Chinese high yield soybean cultivar). A total of 157 polymorphic simple sequence repeat markers were used to construct a genetic linkage map. The phenotypic data of seed and pod traits [number of one-seed pod, number of two-seed pod, number of three-seed pod, number of four-seed pod, number of (two plus three)-seed pod, number of (three plus four)-seed pod, seed weight per plant, number of pod per plant] were recorded in eleven environments. In the analysis of single environment, fourteen main effect QTLs were identified. In the conjoint analysis of multiple environments, twenty-four additive QTLs were identified, and additive QTLs by environments interactions (AE) were evaluated and analyzed at the same time among eleven environments; twenty-three pairs of epistatic QTLs were identified, and epistasis (additive by additive) by environments interactions (AAE) were also analyzed and evaluated among eleven environments. Comparing the results of identification between single environment mapping and multiple environments conjoint mapping, three main effect QTLs with positive additive values and another three main effect QTLs with negative additive values, had no interactions with all environments, supported that these QTLs could be used in molecular assistant breeding in the future. These different effect QTLs could supply a good foundation to the gene clone and molecular asisstant breeding of soybean seed and pod traits.
Identification of resistant sources for pod shattering in a cowpea ( Vigna unguiculata L.) core collection using a modified screening system based on weighted level scores using random impact method
In the present study we evaluated a core set of 254 cowpea genotypes for seven pod physical traits and shattering score using a modified weighted average screening system based on random impact assessment. There was substantial variability in all the pod physical traits and shattering score in the cowpea core collection indicating significant diversity of the material in respect of pod traits. Shattering score had a mean value of 5.39 with a range of 0–10. Out of 254 genotypes, 34 were resistant, 83 were moderately resistant, 82 were moderately susceptible and 55 were highly susceptible. Shattering score had significant negative correlation with pod length followed by pod weight, pod breadth, seeds per pod, pod wall weight and pod thickness. PCA concentrated 69.60% variability in the first two principal components with Eigen value of 4.49 for PC1 and 1.07 for PC2, mainly contributed by pod weight, pod length, pod breadth, pod thickness and pod wall weight. The conventional screening methods are based on level of shattering and do not take into account various types of shattering such as fissured, split, twisted or abscised. The present was aimed at identification of shattering resistant genotypes using a modified screening method based on weighted level averages. The study identified several genotypes highly resistant to pod shattering that can be used to develop shattering resistant cowpea varieties for sustainable cowpea farming and highlights the effectiveness of proposed screening method.
Identification of candidate genes and development of KASP markers for soybean pod-related traits using GWAS
Soybean ( Glycine max [L.] Merr.) is a crop characterized by rich content of oil and protein in seeds, enhancing both yield and quality is considered a pressing challenge in current soybean research and production. Soybean yield is determined by individual traits, including seed number per plant, seed weight per plant, pod number per plant, pod weight per plant and 100−seed weight. Here, 338 resequenced soybean varieties (or lines) were evaluated under two planting densities for five pod−related traits. Substantial variation was detected among the 338 accessions under both densities, and all phenotypic traits followed a normal distribution. A total of 47 and 56 significant SNPs were identified respectively under high and low planting densities through genome−wide association studies (GWAS). Among them, eight SNPs were repeatedly detected across at least two planting densities or environments, and were significantly associated with the seed number per plant (SNPP), seed weight per plant (SWPP) and 100−seed weight (HSW). Based on linkage disequilibrium (LD) analysis, haplotype analysis, gene functional annotation, and qRT−PCR validation, Glyma.20G116200 and Glyma.13G162800 were identified as key genes associated with HSW and SNPP, respectively. Based on this, a KASP marker, S20_35808042 (G/C), was developed and successfully validated in 97 soybean accessions. In summary, these findings hold substantial value for soybean improvement, providing new insights into the genetic architecture of pod−related traits and establishing a conceptual foundation for marker−based selection in breeding programs.
Genome-Wide Association Studies Revealed the Genetic Loci and Candidate Genes of Pod-Related Traits in Peanut (Arachis hypogaea L.)
Cultivated peanut (Arachis hypogaea L.) is one of the most important oilseed crops worldwide. Pod-related traits, including pod length (PL), pod width (PW), ratio of PL to PW (PL/W) and 100-pod weight (100-PW), are crucial factors for pod yield and are key target traits for selection in peanut breeding. However, the studies on the natural variation and genetic mechanism of pod-related traits are not clear in peanut. In this study, we phenotyped 136 peanut accessions for four pod-related traits in two consecutive years and genotyped the population using a re-sequencing technique. Based on 884,737 high-quality single nucleotide polymorphisms (SNPs), genome-wide association studies (GWAS) were conducted for four pod-related traits using a fixed and random model uniform cyclic probability (FarmCPU) model. The results showed that a total of 36 SNPs were identified by GWAS, among which twenty-one, fourteen and one SNPs were significantly associated with PL, PL/W and 100-PW, respectively. The candidate regions where the four peak SNPs (10_76084075, 11_138356586, 16_64420451, and 18_126782541) were located were used for searching genes, and nineteen candidate genes for pod-related traits were preliminarily predicted based on functional annotations. In addition, we also compared the expression patterns of these nineteen candidate genes in different tissues of peanut, and we found that eight genes were specifically highly expressed in tender fruit, immature pericarp, or seed, so we considered these genes to be the potential candidate genes for pod-related traits. These results enriched the understanding of the genetic basis of pod-related traits and provided an important theoretical basis for subsequent gene cloning and marker-assisted selection (MAS) breeding in peanut.
Construction of EMS-Induced Peanut Mutant Libraries and Identification of Pod-Related Traits Mutant Lines
Peanut (Arachis hypogaea L.) is an oil and economic crop of vital importance, and peanut pod is the key organ influencing the yield and processing quality. Hence, the Pod-related traits (PRTs) are considered as important agronomic traits in peanut breeding. To broaden the variability of PRTs in current peanut germplasms, three elite peanut cultivars were used to construct Ethyl methane sulfonate (EMS)-induced mutant libraries in this study. The optimal EMS treatment conditions for the three peanut varieties were determined. It was found that the median lethal dose (LD50) of EMS treatment varied greatly among different genotypes. Finally, the EMS-induced peanut mutant libraries were constructed and a total of 124 mutant lines for PRTs were identified and evaluated. Furthermore, “M-8070”, one of the mutant lines for pod constriction, was re-sequenced via high-throughput sequencing technology. The genome-wide variations between “M-8070” and its wild parent “Fuhua 8” (FH 8) were detected. 2994 EMS-induced single nucleotide polymorphisms (SNPs) and 1188 insertion-deletions (InDels) between “M-8070” and its wild parent were identified. The predominant SNP mutation type was C/G to T/A transitions, while the predominant InDel mutation type was “1-bp”. We analyzed the distribution of identified mutations and annotated their functions. Most of the mutations (91.68% of the SNPs and 77.69% of the InDels) were located in the intergenic region. 72 SNPs were identified in the exonic region, leading to 27 synonymous, 43 non-synonymous and 2 stop-gain variation for gene structure. 13 Indels were identified in the exonic region, leading to 4 frame-shift, 8 non-frame-shift and 1 stop-gain variations of genes. These mutations may lead to the phenotypic variation of “M-8070”. Our study provided valuable resources for peanut improvement and functional genomic research.
Major seed size QTL on chromosome A05 of peanut (Arachis hypogaea) is conserved in the US mini core germplasm collection
Pod and seed size are important characteristics for the peanut industry and have been under strong selection pressure since peanut domestication. In order to dissect the genetic control of peanut pod and seed size, a recombinant inbred mapping population from a cross of Florida-07 by GP-NC WS 16 was used to determine the genomic regions associated with traits including 100 pod weight, 100 seed weight, pod weight of double-seeded pods, seed weight of double-seeded pods, and area of double-seeded pods. Nine QTL on linkage groups (LGs) A05, A06, A09, B10, B04, A03, B05, and B08 were associated with pod and seed size. A majority of the QTL have small effects except the locus on LG A05 (93 to 102 Mbp) which explained up to 66% phenotypic variation for all measured pod and seed traits. A comparison of QTL previously reported for yield component traits showed a common QTL on LG A05 was detected in two genetic populations whose parentage is distinct from those used in this study. The markers tightly linked to this major QTL were informative in distinguishing large versus small-seeded germplasm lines in the mini core collection originating from thirty-one countries, suggesting selection for this seed size QTL in large-seeded ecotypes. However, the large seed size allele appeared to co-segregate with a late leaf spot disease susceptibility allele inherited from the Florida-07 parent. Therefore, peanut breeders need to weigh the pros and cons before integrating the large seed size QTL from Florida-07 in their breeding program.