几种除草剂对当茬玉米生长发育的影响

除草剂为作物产量提供保障的同时,对作物造成的药害也频繁发生。为此,本文以目前陇东旱塬区主栽玉米品种为试验材料,选用对恶性杂草具有良好防除效果的除草剂,明确了75%二氯吡啶酸SG、90%莠去津WG和56% 2甲4氯钠盐SP 3个单剂及其2个混配配方对玉米主要农艺性状及产量的影响,以期为玉米的安全生产提供依据。结果表明：参试除草剂在药后0~7天及不同生育期对玉米生长均无直观影响。75%二氯吡啶酸SG、90%莠去津WG、75%二氯吡啶酸SG+90%莠去津WG对苗期玉米株高稍有影响,但随着玉米自身防御能力的增强,除草剂对之后各生育期的玉米株高无显著抑制作用。不同除草剂对各生育期玉米茎粗无抑制作用,玉米果穗粗、果穗有效长、穗粒数和百粒重无显著差异。各除草剂处理后玉米产量较空白对照增加21.93%~30.22%,较人工除草对照增加-2.91%~3.69%。可见,供试除草剂对玉米安全性高,可应用于玉米田的杂草防除。

Effects of Several Herbicides on the Growth and Development of Maize

While herbicides can ensure crop yield, their phytotoxicity to crops also occurs frequently. The main maize varieties in east dry land of Gansu Province and several herbicides with good efficacy on malignant weeds were used as experimental materials. Field experiments were conducted to study the effects of clopyralid 75% SG, atrazine 90% WG, MCPA-Na 56% SP and their 2 mixtures on main agronomic traits and yield of maize, aims to provide a basis for safe production of maize. The results showed that no herbicides were found to cause visible phytotoxicity to maize 0-7 days after application and at different growth stages. Clopyralid 75% SG, atrazine 90% WG, clopyralid 75% SG + atrazine 90% WG had slight effects on the plant height of maize at seedling stage, but with the enhance of self-defense ability of maize, herbicides had no significant inhibitory effect on the plant height of maize at subsequent growth stages. Different herbicides had no inhibitory effect on the stem diameter of maize at every growth stage, and there was no significant difference in ear diameter, effective ear length, grain numbers of per spike and 100-seeds weight. The yields of maize treated with herbicides increased by 21.93%-30.22% and -2.91%-3.69% compared with the blank control and artificial weed control, respectively. The tested herbicides are highly safe for maize and can be applied to weeds control in maize field.