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Identification of QTLs for pod and kernel traits in cultivated peanut by bulked segregant analysis
Selvaraj, M.G.; Narayana, M.; Schubert, A.M.; Ayers, J.L.; Baring, M.R. & Burow, M.D.
Abstract
Bulked segregant analysis was used to identify simple
sequence repeat (SSR) markers associated with pod and
kernel traits in cultivated peanut, to permit rapid
selection of superior quality genotypes in the breeding
program. SSR markers linked to pod and kernel traits
were identified in two DNA pools (high and low), which
were established using selected F2:6 recombinant
individuals resulting from a cultivated cross between a
runner (Tamrun OL01) and a Spanish (BSS 56) peanut.
To identify quantitative trait loci (QTLs) for pod and
kernel-related traits, parents were screened initially
with 112 SSR primer pairs. The survey revealed 8.9%
polymorphism between parents. Of ten SSR primer
pairs distinguishing the parents, five (PM375, PM36,
PM45, pPGPseq8D9, and Ah-041) were associated with
differences between bulks for seed length, pod length,
number of pods per plant, 100-seed weight, maturity, or
oil content. Association was confirmed by analysis of
segregation among 88 F2:6 individuals in the RIL
population. Phenotypic means associated with markers
for three traits differed by more than 40%, indicating
the presence of QTLs with major effects for number of
pods per plant, plant weight, and pod maturity. The
SSR markers can be used for marker assisted selection
for quality and yield improvement in peanut. To the
best of our knowledge, this is the first report on the
identification of SSR markers linked to pod - and
kernel- related traits in cultivated peanut.
Keywords
maturity, oil quantity, quality, SSR markers
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