我团大面积稻田化学除草已有10多年的历史.在长期生产实践中,我们观察到,每一种除草剂在施药剂量、时间、方法相同的情况下,相对灭草效果的高低和安全与否,与稻田水层深度关系颇大.大多数除草剂的灭草效果与温度呈正相关,即温度越高灭草效果越好,而稻田水层浅的水温和地温较水层深的高,所以前者用除草剂封闭后的灭草效果较后者高.如6-5-1-4条田1984年旱直播后,亩施40%除草醚乳粉400克与无碱细潮土30公斤拌匀制成的毒土,随即进水,到稻苗二叶一心期调查,水层深为5—7厘米的地段,灭稗效果达85—90%,8—12厘米的地段为70-80%,14厘米以上的地段仅50—60%;3-11-3条田旱直播后,亩喷50% In our long-term production practice, we have observed that, in the case of the same dosage, time and method of application of each herbicide, the relative herbicide effect is safe and safe Or not, and the depth of the water layer in paddy field quite large.Most herbicide effect of weed control and temperature were positively correlated, that is, the higher the temperature, the better weed control effect, while the shallow paddy field water temperature and ground temperature is higher than the water depth , So the former Herbicidal effect than the latter after the closure of high herbicides, such as 6-5-1-4 field after direct seeding in 1984, Mushi 40% 400 grams of weeding ether powder and alkali-free soil 30 Kg of soil made of poison, and then into the water, to the rice leaf two leaves one heart phase survey, the water depth of 5-7 cm lot, the effect of barnyardgrass up to 85-90%, 8-12 cm of the lot is 70 -80%, more than 14 cm of the lot only 50-60%; 3-11-3 field drought broadcast, mu spray 50%