杂草稻耐冷性状遗传规律研究

以红长芒杂草稻、白长芒杂草稻、龙粳11、垦稻8号和绥粳3号为亲本材料,配制完全双列杂交。对亲本材料及杂交F1、F2孕穗期耐冷性进行鉴定。结果表明:杂草稻与栽培稻品种相比,优势在于冷水处理下结实率高、成穗率高、后熟快。在冷水处理下,对各组合F1抽穗期、株高、穗数、成穗率、穗粒数、结实率、千粒重、穗颈长、成熟天数等主要性状进行配合力分析,杂草稻多数性状的冷水反应指数值具有较高的一般配合力,以杂草稻作亲本的F1比普通栽培稻品种表现出较迟钝的冷水反应。在耐冷育种中,冷水处理下狭义遗传力高的性状为株高、千粒重和结实率等,且具有较高的一般配合力相对效应值,容易通过对亲本的选择获得所期望的后代,低世代选择效果好。

Study on the Inheritance of Cold Tolerance Characters of Weedy Rice

Red long awn weedy rice, white tong awn weedy rice, Longjing 11, Kendao No. 8 and Suijing No. 3 were selected as parent materials, complete diallel cross was conducted. Cold tolerance in booting stage was identified with parent materials and their F1 and F2 progeny. The results as follows： compared with cultivated varieties, the seed setting rate and the spike rate of weedy rice were higher than those of cultivated varieties, ripening was speeder than that of cultivated varieties with cold water treatment. The combining ability of main characters for F1 progeny of each cross combination such as heading date, plant height, spike number, spike rate, grain number per spike, seed setting rate, 1000-grain weight, neck length of spike and mature stage with cold water treatment were analyzed. Cold response index （CRI） of most characters for weedy rice had higher general combining ability. The cold water response of F1 progeny which weedy rice was the parent was more insensitive than that of cultivated varieties. In cold tolerance breeding, the narrow heritability of plant height, 1000-grain weight and seed setting rate were higher with cold water treatment, and the general combining ability of these characters was higher, in this case, the expected generation would be selected by parent＇s selection, the effect of low generation selection would be better.