主要抗蚜小麦品种(系)的抗性类型及其生化抗性机制

通过对10个抗麦蚜品种(系)室内苗期生命参数、抗性类型和抗蚜次生物质的研究，明确了不同抗性级别的品种对麦蚜种群控制力及部分生化抗蚜机制。实验结果表明，参试的抗蚜品种(系)中30%左右为不选择性：表现为爬行频繁，定殖率低，但是定殖个体生长发育良好；70%为抗生性；表现为使麦长管蚜Sitobion avenae(F.)和禾谷缢管蚜只Rhopalosiphum padi(L.)的发育历期分别延长2.1%～28.2%和3.7%～13.9%，若蚜死亡率增加1.0～3.6倍和1.0～2.25倍，平均寿命缩短10.2%～96.5%和37.5～97，1%，繁殖力下降3.4%～72.8%和25%～97.2%。苗期生化测定结果表明：不同抗源的单宁和总酚含量明显高于感蚜品种，其总酚含量与抗麦长管蚜级别呈显著负相关，以抗生性为主的品种其总酚含量亦与麦长管蚜的内禀增长力(r_m)呈显著负相关(P<0.05)，表明总酚是小麦抗长管蚜的关键因子之一，而与禾谷缢管蚜抗性水平无关；单宁含量与麦蚜抗性关系不密切。

THE RESISTANT PATTERNS AND MECHANISM OF BIOCHEMICAL RESISTANCE IN VARIOUS WHEAT CULTIVARS (LINES)

Ten winter wheat cultvars (lines) with different degrees of resistance to wheat aphids were studied at seedling stage under the lab condition on the parameters of life table, resistant patterns and the content of some secondary substances in the plant tissues. The control capacity on Sitobion avenae F. (SA) andRhopalosiphurn padi L.(RP) and partial biochemical resistant mechanism have been revealed. The results showed the resistant patterns of cultivars to wheat aphid being 30% non-perference and70% antibiosis. The non-perference resistant cultivars made aphids crawling frequently and decreasing the colonial rate on wheat leaf greatly, but the colonial individuals and their growth rate and fecundity were as CK. The cultivars with different degrees of an-tibiosis resistance made SA and RP nymphal development prolonged by 2.1%-28.2% and 3.7%-13.9%, nymphal mortality increased 1.0-3. 6 and 1.0-2.25 times, average longivity shortened by 10.2%-96. 5% and 37.5%-97.1% and fecundity decreased by 3.4%-72.8% and 25%-97.2%, respectively. The result of biochemical analysis at seedling stage showed that there were significant differences in the contents of tannin and phenolic in plant tissues between the resistant and susceptible cultivars. The correlation between phenolic content and the resistant degree to SA was negatively significant(P＜0.05). The correaltion between phenolic content and the innate capacity for increase (r_m) of SA was also negatively significant. So, phenols in plant tissues seem to be one of the key resistant factors to SA. No correlation between phenolic content and the resistant degree to RP or rm of RP was found. There was no correlation between tannin content and the resistant degree to both wheat aphids.