Close linkage of a blast resistance gene, Pias(t), with a bacterial leaf blight resistance gene, Xa1-as(t), in a rice cultivar 'Asominori'.
It has long been known that a bacterial leaf blight-resistant line in rice obtained from a crossing using 'Asominori' as a resistant parent also has resistance to blast, but a blast resistance gene in 'Asominori' has not been investigated in detail. In the present study, a blast resistance gene in 'Asominori', tentatively named Pias(t), was revealed to be located within 162-kb region between DNA markers YX4-3 and NX4-1 on chromosome 4 and to be linked with an 'Asominori' allele of the bacterial leaf blight resistance gene Xa1, tentatively named Xa1-as(t). An 'Asominori' allele of Pias(t) was found to be dominant and difference of disease severity between lines having the 'Asominori' allele of Pias(t) and those without it was 1.2 in disease index from 0 to 10. Pias(t) was also closely linked with the Ph gene controlling phenol reaction, suggesting the possibility of successful selection of blast resistance using the phenol reaction. Since blast-resistant commercial cultivars have been developed using 'Asominori' as a parent, Pias(t) is considered to be a useful gene in rice breeding for blast resistance.
NARO Tohoku Agricultural Research Center , 3 Shimo Furumichi, Daisen, Akita 014-0102, Japan ; Present address: Miyagi Prefectural Furukawa Agricultural Experiment Station, 88 Fukoku, Osaki, Miyagi 989-6227, Japan.
Takashi
T
Endo
Masayuki
M
Yamaguchi
Ryota
R
Kaji
Koji
K
Nakagomi
Tomomori
T
Kataoka
Narifumi
N
Yokogami
Toshiki
T
Nakamura
Goro
G
Ishikawa
Jun-Ichi
J
Yonemaru
Takeshi
T
Nishio
Xa1; bacterial leaf blight resistance; leaf blast resistance; phenol reaction; rice; ‘Asominori’