Role of the rice blast resistance gene Pi‐cd in rice (Oryza sativa) breeding programmes.

A series of DNA markers for various agronomic traits may accelerate the success of marker‐assisted selection in practical plant breeding programmes. Here, we developed DNA markers for the blast resistance gene Pi‐cd. In this study, we examined the effects of the Pi‐cd locus on not only blast resistance but also agronomic traits in agriculture. We developed three pyramiding lines (PLs) coupling Pi‐cd with three blast resistance genes, pi21, Pi35 and Pi39. The effect of Pi‐cd on blast resistance was dependent on the coupled resistance genes. Then, we evaluated the effects of Pi‐cd on 13 agronomic traits. Amylose content and 1,000‐grain weight showed significant differences between the PLs and current commercial varieties, which had no negative effects on agronomic trait values. Furthermore, we investigated the distribution of genotype for the Pi‐cd locus among varieties of upland rice. The KT genotype specific to rice blast resistance may be predominant in the varieties. The results suggested that Pi‐cd has the potential to be useful for improving blast resistance in rice breeding programmes. [ABSTRACT FROM AUTHOR]