小麦抗赤霉病基因库研究——Ⅵ.轮选品系与原始亲本的综合分析与比较

Studies on the Development of Scab Resistant Gene Pool in Wheat——Ⅵ. Comprehensive Analysis and Comparison of the Scab Resistance and Agronomic Traits of Recurrent Selection Strains and Their Original Parents

用26个来自基因库的轮选品系或抗源材料和19个原始亲本,在赤霉病单花接种条件下,对抗性和16个农艺性状进行综合分析与比较。平均而言,从接种后16～17天到26～27天,病小穗数和病小穗率的扩增值,轮选品系比原始亲本分别少1.32个和7.11％。病小穗数和病小穗率最终观察值,轮选品系分别为5.35个和24.39％,比原始亲本分别低2.72个和14.75％。轮选品系和原始亲本的平均抗赤霉病忭(抗扩展)分别为MR和MS级。与原始亲本相比,轮选品系的平均株高降低近20cm,生物量、籽粒产量、穗粒数、千粒重、收获指数等重要农艺性状均得到显著改进。部分轮选品系不仅抗赤性较强,而且主要农艺性状也较优良,与推广品种扬麦5号相当或相近。育种实践证明,利用ms2(Tal)基因通过轮回选择建拓抗赤霉病基因库,并结合常规育种,是小麦抗赤霉病遗传改良的有效途径。

The scab resistance and agronomic characters of 26 recurrent selection strains from the scab resistant gene pool of wheat and 19 original parents were comprehensively analyzed and compared after single-floret inoculation with Cibberella zeae. On the average, the increased number and percentage of diseased spikelets in the recurrent selection strains were 1. 32 and 7. 11% less than those of their original parents, respectively, from 16-17 days to 26-27 days after inoculation. The mean number and percentage of diseased spikelets observed on the 26-27th day after inoculation were 5. 35 and 24. 39% for the recurrent selection strains, respectively, and were 2. 72 and 14. 75% less than those of their original parents. The mean resistance level of the recurrent selection strains to scab spread was moderately resistant (MR) but that of their original parents was moderately susceptible (MS). The mean plant height of the recurrent selection strains was about 20 cm shorter than that of their original parents. The biomass, grain yield per plant and stalk, number of grains per spike, 1000-grain weight and harvest index were also significantly improved. Some of the recurrent selection strains possess not only higher resistance to scab but also desirable agronomic characteristics, These results further demonstrated that the development of scab resistant gene pool, using the dominant male-sterile gene ms2 (Tal) , in combination with conventional breeding is an effective approach for the improvement of scab resistance in wheat.