水稻黃萎病抗病性之遺傳研究

Abstract

為探究水稻黃萎病抗病性之遺傳行為，利用黃萎病感病品種臺農61號和臺南5號分別與抗病品種Firooz-(1)和Kabara進行雜交，其F1再與兩雜交親本回交和自交，同時獲有F1、F2、BCPS、F12、BCPR等雜交世代材料，再將此等材料與親本同時種植，於幼苗期進行黃萎病抗病性檢定。第一年以以集團接種法在幼苗長至5~6公分時接種帶菌質昆蟲24小時（蟲苗比1.5倍），然後種植田間；第二年以個體接種法在幼苗長至10~15公分約2~3葉齡時接種帶菌質昆蟲24小時（一試管一幼苗，放入兩隻帶菌質昆蟲），然後移植於塑膠盆中。移植後約5~6週病徵即開始出現，經初步調查後將其宿根，宿根後2~3週間詳細調查宿根後之發病情形，並進行遺傳分離法則符合度測驗，結果顯示黃萎病抗病品種Firooz-(1)和Kabara之抗病性係受一對顯性抗病因子所支配。 This study was designed to investigate the inheritance of yellow dwarf disease in rice. Two susceptible varieties, Tainung 61 and Tainan 5, were crossed with two resistant varieties, Firooz-(1) and Kabara and the F1’s were seif-polinated and backcrossed to their respective parents. Seedlings of F1, F2, BCPS and BCPR were inoculated with vector insects (Nephotettix nigropictus and N. cincticeps) for 24 hours. In the first experiment, the seedlings of 5-6 cm in height were inoculated by the mass inoculation method. In the second experiment the seedlings of 10-15 cm in height which were about at 2- or 3-leaf stage were inoculated by the individual inoculation method. Five to six weeks after inoculation, the degree of resitance to yellow dwarf disease was investigated and then the upper part of the plants near the land about 5-6 cm were cut out (ratoon). Two to three weeks later, another detail investigation was made on ratoons. It was found that the resistance of Firooz-(1) and Kabara to yellow dwarf disease was controlled by a single dominant gene.