5种除草剂对油菜ALS酶活性的影响及杀雄作用评价

摘要

在油菜杂种优势利用中，为筛选新型化学杀雄剂，有效诱导雄性不育，以甘蓝型油菜自交系740C和Q8C为材料，使用5种除草剂（苯磺隆、氯吡嘧磺隆、环氧嘧磺隆、双草醚和阔草清），各4个稀释浓度（1／200、1／100、3／200、1／50）对现蕾期的植株进行喷施，在处理后1至4d分别采取油菜叶片和花蕾，测定乙酰乳酸合成酶（acetolac-tate synthase，ALS）酶活性，并在后期进行花粉活力的测定和育性分析。结果表明：双草醚、阔草清能够抑制ALS酶的活性但不具有化学杀雄作用。同一药剂不同浓度处理的油菜体内ALS酶活性表现为随药剂浓度升高而降低的趋势。740C比Q8C对5种除草剂更敏感，ALS酶活性抑制程度更明显。老叶、幼叶、花蕾对化学杀雄剂的敏感程度依次增加，其ALS酶活性逐步降低。筛选出氯吡嘧磺隆和环氧嘧磺隆，可以作为候选化学杀雄剂，适合浓度分别是1．3～2．6mg／L和1．5～3．0mg／L。%Chemical hybridization agent is used to induce male sterility which is one of the effective ways to uti-lize rapeseed heterosis.To select better herbicide as chemical hybridizing agent in fields,5 herbicides were studied which inhibited rapeseed acetolactate synthase (ALS).5 herbicides including tribenuron-methyl,halosulfuron-methyl,oxasulfuron,bispyribac-sodium,and flumetsulam,were sprayed on Brassica napus inbred lines 740C and Q8C at bolting stage.Each herbicide was tested in 4 concentrations:1/200,1/100,3/200 and 1/50 of the bench-mark concentrations respectively.In vivo enzyme activities of ALS were assayed from leaves and buds collected dur-ing 1 -4 d after spray.Pollen viability was tested.Results showed that bispyribac and flumetsulam inhibited ALS activity without gametocidal effect.ALS enzyme activities of treated plants under different herbicide concentrations decreased with concentrations.740C was more sensitive than Q8C.The decrease of ALS activity was more promi-nent.ALS activities decreased gradually in old leaves,young leaves and flower buds,which indicated the increase of sensitivity.Halosulfuron and oxasulfuron could be used as potential chemical hybridizing agents on rapeseed un-der 1.3 to 2.6mg/L and 1.5 to 3.0mg/L respectively.