Development of a molecular linkage map of pearl millet
integrating DArT and SSR markersASupriyaauthorSSenthilvelauthorTNepoleanauthorK EEshwarauthorVRajaramauthorRShawauthorC THashauthorAKilianauthorR CYadavauthorM LNarasuauthorPearl millet is an important component of
food security in the semi-arid tropics and is assuming
greater importance in the context of changing climate and
increasing demand for highly nutritious food and feed.
Molecular tools have been developed and applied for pearl
millet on a limited scale. However, the existing tool kit
needs to be strengthened further for its routine use in
applied breeding programs. Here, we report enrichment of
the pearl millet molecular linkage map by exploiting
low-cost and high-throughput Diversity Arrays Technology
(DArT) markers. Genomic representation from 95 diverse
genotypes was used to develop a DArT array with circa
7,000 clones following PstI/BanII complexity reduction.
This array was used to genotype a set of 24 diverse pearl
millet inbreds and 574 polymorphic DArT markers were
identified. The genetic relationships among the inbred lines
as revealed by DArT genotyping were in complete agreement
with the available pedigree data. Further, a mapping
population of 140 F7 Recombinant Inbred Lines (RILs)
from cross H 77/833-2 9 PRLT 2/89-33 was genotyped
and an improved linkage map was constructed by integrating
DArT and SSR marker data. This map contains 321
loci (258 DArTs and 63 SSRs) and spans 1148 cM with an
average adjacent-marker interval length of 3.7 cM. The
length of individual linkage groups (LGs) ranged from
78 cM (LG 3) to 370 cM (LG 2). This better-saturated map
provides improved genome coverage and will be useful for
genetic analyses of important quantitative traits. This DArT
platform will also permit cost-effective background selection
in marker-assisted backcrossing programs as well as
facilitate comparative genomics and genome organization
studies once DNA sequences of polymorphic DArT clones
are available.Millets2011Springer VerlagArticle