3种茎叶处理除草剂在胡麻田的最佳施药期研究

Optimal spraying stage of three post-emergence herbicides in flax field

为了筛选出对胡麻安全、对杂草防效优良的茎叶除草剂最佳喷施时期,田间测定了400 g/L 2甲·溴苯腈EC 1500 mL/hm^(2)、56%2甲4氯钠SP 1200 g/hm^(2)和40%2甲·辛酰溴EC 1275 mL/hm^(2)在不同时期喷施对胡麻生长发育的影响及对田间杂草的防效。通过对胡麻株高、鲜重、产量及控草效果综合分析看出:400 g/L 2甲·溴苯腈EC在胡麻株高5 cm、56%2甲4氯钠SP在胡麻株高2.5~5 cm、40%2甲·辛酰溴EC在胡麻株高5~10 cm喷施,对胡麻株高的抑制作用均能在成熟期降至微弱或无影响,对胡麻鲜重的抑制作用均能提早减轻至微弱甚至无影响;胡麻生物产量分别较人工除草增加9.66%、-6.25%~-1.77%和7.19%~9.97%,胡麻籽粒产量分别较人工除草增加5.39%、-0.86%~-0.47%和-0.56%~5.45%;对阔叶杂草株防效分别达到81.82%、51.46%~73.88%和51.91%~67.21%,对阔叶杂草鲜重防效分别达到98.99%、88.96%~96.33%和91.26%~94.47%。可见,参试除草剂在上述时期喷施对胡麻安全、对杂草防效理想,可大面积推广。

In order to screen out the optimal time to spray the herbicide which is safe to flax and has great control effect on weeds,the effect of MCPA-Na·bromoxynil 400 g/L EC 1500 mL/hm 2,MCPA-Na 56%SP 1200 g/hm 2 and MCPA-Na·bromoxynil octanoate 40%EC 1275 mL/hm 2 on the growth and development of flax and their efficiency on field weeds at different periods were investigated,and the effect of herbicides on the height,fresh weight,yield of flax and its control effect on field weeds were also analyzed.The result showed that MCPA-Na·bromoxynil 400 g/L EC,MCPA-Na 56%SP and MCPA-Na·bromoxynil octanoate 40%EC had no obvious effect to the height and fresh weight of mature flax sprayed separately at flax height of 5 cm,2.5-5 cm and 5-10 cm.The biological yield of flax increased by 9.66%,-6.25%to-1.77%and 7.19%to 9.97%,and the grain yield increased by 5.39%,-0.86%to-0.47%and-0.56%to 5.45%,respectively,compared with hand weeding.Control effects on broadleaf weeds were 81.82%、51.46%to 73.88%and 51.91%to 67.21%,and the fresh weight control efficiency on broadleaf weeds were 98.99%,88.96%to 96.33%and 91.26%to 94.47%,respectively.In conclusion,the tested herbicides had best control effect on broadleaf weeds sprayed during the above mentioned periods and were also safe to flax,which had the value of popularization in agricultural production.