三种除草剂对外来入侵植物大狼耙草的防除效果

大狼耙草是危害生物多样性的一种恶性杂草。使用使它隆、二甲四氯、草甘膦3种除草剂对大狼耙草进行不同浓度、不同防治时期防除效果研究,结果表明:使它隆对大狼耙草平均致死率为92%,二甲四氯为85%,草甘膦为82%,但三者差异不显著;高、中、低3种浓度(使它隆分别为0.47、0.40、0.33g·L-1,二甲四氯分别为2.80、2.33、1.87g·L-1,草甘膦分别为5.18、3.89、2.59g·L-1)对大狼耙草致死率差异极显著,高浓度溶液防除效果较好;大狼耙草植株在幼苗期(植株高20cm)、生长盛期(植株高40cm)、花期(植株高60cm)3个防治时期致死率差异极显著,幼苗期防除效果理想。研究表明,在大狼耙草幼苗期使用0.47g·L-1浓度的使它隆防除效果最好。

Controlling effect of three herbicides on an alien invasive plant Bidens frondosa

Bidens frondosa is an exotic vicious weed which endangers biodiversity.In this study,a field experiment was conducted to investigate the controlling effect of different concentrations and different application periods of herbicides Starane,MCPA,and glyphosate on B.frondosa.All the three herbicides had significant controlling effect on this weed,with the average lethality of Starane,MCPA,and glyphosate being 92%,85%,and 82%,respectively,but no significant difference among them.Different concentrations of the herbicides(0.47,0.40 and 0.33 g·L-1 of Starane;2.80,2.33 and 1.87 g·L-1 of MCPA;and 5.18,3.89 and 2.59 g·L-1 of glyphosate) had significant differences in the lethality on B.frondosa,and relatively high concentration could obtain better controlling effect.The application period of the herbicides also had significant effects in controlling B.frondosa.Applying the herbicides at B.frondosa seedling stage(plant height 20 cm) could achieve better controlling effect than at its fast growing stage(plant height 40 cm) and blooming stage(plant height 60 cm).It was suggested that applying 0.47 g·L-1 of Starane at the seedling stage of B.frondosa would obtain the best controlling effect.