甘蓝型油菜抗除草剂恢复系18Z363苯磺隆抗性剂量筛选

Tribenuron-methyl Tolerance of Brassica napus Restorer Line 18Z363

【目的】研究不同剂量苯磺隆对甘蓝型油菜苗期叶绿素含量、存活率及成熟期农艺性状的影响,为波里马细胞质不育(polima cytoplasmic male sterility, pol CMS)恢复系18Z363筛选安全、有效、经济的苯磺隆除草剂施用量提供依据。【方法】以pol CMS恢复系18Z363、M342、2350C及杂交种LDX95-58A×18Z363为试验材料,盆栽种植于4-6叶期喷施不同剂量的苯磺隆,7 d后采用SPAD-502叶绿素测定仪测量叶片的叶绿素含量,14 d后调查存活率;大田种植4-6叶期喷施不同剂量的苯磺隆,于成熟期考察主要农艺性状。【结果】油菜叶片叶绿素含量SPAD值随苯磺隆施用剂量的增加而下降,在18.0 g·hm^-2及以上剂量处理下,不抗除草剂材料2350C叶片叶绿素含量SPAD值显著下降到较低水平,而抗除草剂材料18Z363、M342及杂交种LDX95-58A×18Z363的SPAD值仍保持较高水平;18.0 g·hm^-2处理下不抗除草剂材料2350C存活率为0,而18Z363、M342及杂交种LDX95-58A×18Z363存活率在88.9%以上;高于18.0 g·hm^-2剂量的苯磺隆处理对18Z363、M342及杂交种LDX95-58A×18Z363成熟期的主要农艺性状造成不同程度的负面影响。【结论】pol CMS恢复系18Z363及配制的"三系"杂交种的最适苯磺隆施用剂量为18.0 g·hm^-2。

【Objective】 Effects of the herbicide, tribenuron-methylon, in varied concentrations on the survival rate,chlorophyll content, and agronomic traits of Brassica napus L. were studied to determine the appropriate dosage for field application.【Method】 In a pot experiment, seedlings of B. napus polima cytoplasmic male sterility(pol CMS) restorer lines,including 18 Z363, M342, 2350 C, and the hybrid(LDX95-58 A×18 Z363), at 4 to 6 leaves stage were sprayed with tribenuronmethylon solutions in varied concentrations. Chlorophyll contents in leaves of the plants were measured 7 d after treatments using a SPAD-502 chlorophyll meter. Survival rates of the seedlings were determined 14 d after the spraying. In the field,agronomic traits of the mature plants, which had been treated at 4 to 6 leaves stage, were observed.【Result】 Overall, the leaf SPAD decreased with increasing herbicide dosage applied on the plants. When the application dosage was greater than or equal to 18.0 g·hm^-2, it declined significantly in the herbicide-susceptible line 2350 C reaching a low level, but remained high in the resistant lines 18 Z363, M342, and the hybrid. Meanwhile, all 2350 C seedlings died in 2 weeks, whereas, more than 88.9% of18 Z363, M342 or the hybrid survived the treatments. Once the herbicide application was beyond 18.0 g·hm^-2, even the resistant species began to show ill-effects in varying degrees on the agronomic traits.【Conclusion】 The results appeared that the upper limit of tribenuron-methyl usage around the restorer line18 Z363 and its hybrids was 18.0 g·hm^-2.