Dataset Information

Identification of genetic loci associated with crude protein and mineral concentrations in alfalfa (Medicago sativa) using association mapping.

ABSTRACT:

Background

Alfalfa (Medicago sativa) is one of the most important legume forage species in China and many other countries of the world. It provides a quality source of proteins and minerals to animals. Genetic underpinnings for these important traits, however, are elusive. An alfalfa (M. sativa) association mapping study for six traits, namely crude protein (CP), rumen undegraded protein (RUP), and four mineral elements (Ca, K, Mg and P), was conducted in three consecutive years using a large collection encompassing 336 genotypes genotyped with 85 simple sequence repeat (SSR) markers.

Results

All the traits were significantly influenced by genotype, environment, and genotype × environment interaction. Eight-five significant associations (P < 0.005) were identified. Among these, five associations with Ca were repeatedly observed and six co-localized associations were identified.

Conclusions

The identified marker alleles significantly associated with the traits provided important information for understanding genetic controls of alfalfa quality. The markers could be used in assisting selection for the individual traits in breeding populations for developing new alfalfa cultivars.

SUBMITTER: Jia C

PROVIDER: S-EPMC5460482 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Publications

Identification of genetic loci associated with crude protein and mineral concentrations in alfalfa (Medicago sativa) using association mapping.

Jia Congjun C Wu Xinming X Chen Min M Wang Yunqi Y Liu Xiqiang X Gong Pan P Xu Qingfang Q Wang Xuemin X Gao Hongwen H Wang Zan Z

BMC plant biology 20170606 1

<h4>Background</h4>Alfalfa (Medicago sativa) is one of the most important legume forage species in China and many other countries of the world. It provides a quality source of proteins and minerals to animals. Genetic underpinnings for these important traits, however, are elusive. An alfalfa (M. sativa) association mapping study for six traits, namely crude protein (CP), rumen undegraded protein (RUP), and four mineral elements (Ca, K, Mg and P), was conducted in three consecutive years using a ...[more]

PMID: 28583066

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Project description:BackgroundThe genetic and genomic basis of flowering time and biomass yield in alfalfa (Medicago sativa L.) remains poorly understood mainly due to the autopolyploid nature of the species and the lack of adequate genomic resources. We constructed linkage maps using genotyping-by-sequencing (GBS) based single dose allele (SDA) SNP and mapped alfalfa timing of flowering (TOF), spring yield (SY), and cumulative summer biomass (CSB) in a pseudo-testcross F1 population derived from a fall dormant (3010) and a non-dormant (CW 1010) cultivars. We analyzed the quantitative trait loci (QTL) to identify conserved genomic regions and detected molecular markers and potential candidate genes associated with the traits to improve alfalfa and provide genomic resources for the future studies.ResultsThis study showed that both fall dormant and non-dormant alfalfa cultivars harbored QTL for early and late flowering, suggesting that flowering time in alfalfa is not an indicator of its fall dormancy (FD) levels. A weak phenotypic correlation between the flowering time and fall dormancy (FD) in F1 and checks also corroborated that alfalfa FD and TOF are not the predictors of one another. The relationship between flowering time and alfalfa biomass yield was not strong, but the non-dormant had relatively more SY than dormant. Therefore, selecting superior alfalfa cultivars that are non-dormant, winter-hardy, and early flowering would allow for an early spring harvest with enhanced biomass. In this study, we found 25 QTL for TOF, 17 for SY and six QTL for CSB. Three TOF related QTL were stable and four TOF QTL were detected in the corresponding genomic locations of the flowering QTL of M. truncatula, an indication of possible evolutionarily conserved regions. The potential candidate genes for the SNP sequences of QTL regions were identified for all three traits and these genes would be potential targets for further molecular studies.ConclusionsThis research showed that variation in alfalfa flowering time after spring green up has no association with dormancy levels. Here we reported QTL, markers, and potential candidate genes associated with spring flowering time and biomass yield of alfalfa, which constitute valuable genomic resources for improving these traits via marker-assisted selection (MAS).

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Dataset Information

Identification of genetic loci associated with crude protein and mineral concentrations in alfalfa (Medicago sativa) using association mapping.

Background

Results

Conclusions

Publications

Identification of genetic loci associated with crude protein and mineral concentrations in alfalfa (Medicago sativa) using association mapping.

Similar Datasets

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