Reference "Identification of heading date quantitative trait locus Hd6 and characterization of its epistatic interactions with Hd2 in rice using advanced backcross progeny"

Reference ID

6943

Title

Identification of heading date quantitative trait locus Hd6 and characterization of its epistatic interactions with Hd2 in rice using advanced backcross progeny

Source

Genetics, 2000, vol. 154, pp. 885-891

Authors (4)

Yamamoto-T	Lin-H
Sasaki-T	Yano-M

Abstract

A backcrossed population (BC(4)F(2)) derived from a cross between a japonica
rice variety, Nipponbare, as the recurrent parent and an indica rice variety,
Kasalath, as the donor parent showed a long-range variation in days to heading.
Quantitative trait loci (QTL) analysis revealed that two QTL, one on chromosome
3, designated Hd6, and another on chromosome 2, designated Hd7, were involved in
this variation; and Hd6 was precisely mapped as a single Mendelian factor by
using progeny testing (BC(4)F(3)). The nearly isogenic line with QTL (QTL-NIL)
that carries the chromosomal segment from Kasalath for the Hd6 region in
Nipponbare's genetic background was developed by marker-assisted selection. In a
day-length treatment test, the QTL-NIL for Hd6 prominently increased days to
heading under a 13.5-hr day length compared with the recurrent parent,
Nipponbare, suggesting that Hd6 controls photoperiod sensitivity. QTL analysis
of the F(2) population derived from a cross between the QTL-NILs revealed
existence of an epistatic interaction between Hd2, which is one of the
photoperiod sensitivity genes detected in a previous analysis, and Hd6. The day-
length treatment tests of these QTL-NILs, including the line introgressing both
Hd2 and Hd6, also indicated an epistatic interaction for photoperiod sensitivity
between them.