Reference "Molecular dissection of the genetic relationships of source, sink and transport tissue with yield traits in rice"

Reference ID

7856

Title

Molecular dissection of the genetic relationships of source, sink and transport tissue with yield traits in rice

Source

Theoretical and applied genetics, 2003, vol. 106, pp. 649-658

Authors (6)

Cui-H	Peng-B
Xing-Z	Yu-B
Xu-G	Zhang-Q

Abstract

Source, sink, and translocation capacity of assimilates play important roles
during the formation of grain yield. The present study was conducted to
characterize the genetic bases of traits representing source, sink and transport
tissue, and their relationships with yield traits in rice, by analyzing QTLs for
these traits and various ratios among them. The genetic materials were a
recombinant inbred population derived from a cross between two indica cultivars
Zhenshan 97 and Minghui 63, the parents of the most-widely grown hybrid rice in
China. Using a linkage map that covers a total of 1,796 cM based on 221
molecular marker loci, a total of 81 QTLs were identified for the 15 traits
studied (three leaf areas as the source, total spikelets per panicle as the
sink, the number of large vascular bundles in the stem as transport tissue,
three source to sink ratios, three transport tissue to source ratios, one
transport tissue to sink ratio and three yield traits). The amount of variation
explained by individual QTLs ranged from 1.12% to 24.14%. Five QTLs were
identified to show interaction effects with the environment, which explained
from 3.19% to 9.15% of the variation. The results showed that close linkage or
pleiotropy is the genetic basis for the correlations of grain yield traits with
source, sink, transport tissue and the various ratios among them. Of the 25 QTLs
identified for source-sink-transport tissue trait, and 43 for various ratios, 8
and 22 QTLs, respectively, were mapped to the similar genomic blocks harboring
QTLs for yield traits, especially for grain weight. Co-location of QTLs for
yield traits with those for ratios among source, sink and transport tissue may
provide a genetic explanation for the physiological expression of yield traits,
and also suggest that improvement in ratios among source, sink and transport
tissue may result in improvement in yield potential.