Confirmations on gene introgression events and hybridity for BLB resistance and yield in rice

Muh Aswad Ashan; Reflinur; Sintho Wahyuning Ardie

doi:10.24831/jai.v51i3.51194

Muh Aswad Ashan Plant Breeding and Biotechnology Study Program, Graduate School of IPB University (Bogor Agricultural University), Jl. Meranti, Kampus IPB Dramaga, Bogor 16680, INDONESIA
Reflinur Research Center for Genetic Engineering, Research Organization for Life Science and Environment, National Research and Innovation Agency, Jl. Raya Bogor Km 46, Cibinong, Bogor 16911, INDONESIA
Sintho Wahyuning Ardie Department of Agronomy and Horticulture, Faculty of Agriculture, IPB University (Bogor Agricultural University), Jl. Meranti, Kampus IPB Dramaga, Bogor 16680, INDONESIA

DOI: https://doi.org/10.24831/jai.v51i3.51194

Abstract

A superior variety of rice with high yield and resistance to diseases is expected to meet the increasing demand for this one of the most important carbohydrate sources worldwide. Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the major biotic stresses limiting rice production. Combining BLB resistance and high-yield traits is possible through gene pyramiding. Introgression of targeted traits in the parental genotypes and hybridity confirmation in the F₁ generation are important initial steps in gene pyramiding. This study aimed to confirm the presence of targeted genes in parent genotypes using specific molecular markers and to confirm the hybridity of F₁ plants generated from three crosses combinations of Inpari 32 (as the female parent) and three Code-qTSN4 lines (as the male parents) using SSR markers. This study successfully confirmed the introgression of BLB-resistance genes in Inpari 32 (Xa4, Xa7, and Xa21) and in Code-qTSN4 (Xa4, Xa7). The introgression of yield-related QTL, qTSN4, was confirmed in the three Code-qTSN4 lines (A10-1, B12-2, and A16-5) by RM17483 marker. Five SSR markers (RM5, RM55, RM105, RM223, and RM561) successfully confirmed the hybridity of F₁ derived from Inpari 32xA10-1 (five individuals), Inpari 32xB12-2 (one individual), Inpari 32xA16-5 (two individuals). These confirmed hybrids can be further evaluated in the F₂ generation.

Keywords: Gene pyramiding; molecular marker; SSR; qTSN4; Xoo.