不同品种油菜对苯磺隆耐药性差异的鉴定

Identification of the Tribenuron-methyl Tolerance in Different Rapeseed Genotypes

首先以中双9号油菜为试材,探索适宜油菜筛选的苯磺隆药液质量浓度和鉴定指标。叶片药害指数、叶片数减少率、叶夹角减少率与植株死亡率间均存在显著或极显著相关关系,说明这3个指标可作为早期鉴定油菜对苯磺隆耐药性的指标。用上述试验筛选出的2.0μg·mL-1苯磺隆溶液处理49个不同基因型油菜幼苗,根据叶片药害指数、叶片数减少率、叶夹角减少率、植株死亡率4个指标计算出的耐苯磺隆平均隶属函数值(AS)将参试材料分为3个等级,低度敏感材料2份(AS<0.33)、中度敏感材料22份(0.33≤AS<0.67)、高度敏感材料25份(AS≥0.67)。参试材料对苯磺隆抗性存在一定差异,但与小麦田推荐的苯磺隆使用质量浓度相比,油菜对苯磺隆抗性水平还很低,说明利用油菜种内基因资源,进行抗苯磺隆油菜育种潜力有限。

In this study, Zhongshuang 9 rapeseed （Brassica napus L. ） was used as the material to in-vestigate the suitable concentration of tribenuron-methyl treatment and screening suitable indicators for evaluation the resistance. The result indicated that phytotoxicity index, inhibition ratio of leaf number, inhibition ratio of leaf angle significantly correlated with death ratio, so they were recom-mended as key index for tribenuron-methyl resistance screening at seedling stage. Seedlings of 49 rapeseed accessions were foliar sprayed with 2.0μg· mL^-1 tribenuron-methyl solution and were clas- sified into three groups based on the average subordinate function （AS） calculated by phytotoxicity in- dex, inhibition ratio of leaf number, inhibition ratio of leaf angle and death ration. Two accessions were grouped into the low sensitive material （AS〈0.33）, 22 accessions into the moderately sensitive material （0.33≤AS〈0. 67）, 25 accessions into highly sensitive materials （AS ≥0.67）. Although there existed some resistance di{ferences among the tested materials to tribenuron-methyl, their resist- ances were very low compared with the recommended concentration of tribenuron-methyl for weed control in wheat field. These results suggested that breeding potential of rapeseed varieties with re- sistance to tribenuron-methyl by using the genetic variation within B. napus gene pool was limited.