There are so many herbicides, do you know how to use them?

Most of the "alachlor" herbicides on the market are amide herbicides, and most of them are soil treatment agents, which are mainly applied before sprouting after sowing. The control effect of annual Gramineae weeds is good, but the control effect of broad-leaved weeds is poor. In general, the control effect is Acetochlor > Metolachlor = Metolachlor > Butachlor > Acetochlor > Poisachlor.

Acetochlor: the duration was 40-70 days. It is mainly kept in the soil layer of 0~3cm, and it is easy to cause drug damage under high temperature, high humidity or continuous low temperature and high humidity after treatment, but it can return to normal after 10 to 15 days. It is easy to cause drug damage when applied 24-72 hours after sowing. The main part of weed absorption is bud, so the pesticide must be applied before weeds are unearthed.

Metolachlor: the effect lasted for 30 to 35 days, and the activity disappeared naturally at 10 to 12 weeks after administration. Monocotyledon Gramineae weeds were absorbed mainly through bud sheath, dicotyledonous weeds were absorbed and transmitted upward through young buds and roots, and inhibited the growth of buds and fine roots. sensitive weeds died of poisoning before or just after germination. The absorption capacity of Gramineae weeds is stronger than that of broad leaves. It is suitable to apply the drug 3-5 days before transplanting, and before emergence 1-2 days after direct seeding in the field, the drug is easy to be degraded by soil microorganisms, and the effect is medium.

Alachlor: the general time to control weeds is about 60 days. Can be absorbed by the soil, not easy to leaching, not easy to volatilize failure. Rice, sorghum, millet, cucumber, leek and spinach are very sensitive to it. The depth of concrete should not exceed 5cm.

Prochlor: the duration of effect in paddy field is 30-50 days. When used alone, it can only be used for transplanting rice fields, and it will damage the seedlings when used in seedling fields and direct seeding fields. However, the addition of safety agent can make up for the deficiency. When the application amount is too large, the seedling heart leaf, leaf tip to leaf edge turn green and curl, and the plant growth is inhibited.

Ketochlor: the duration is about 40 days. Cucumber is very sensitive to it, and its safety is worse than butachlor, so it is not suitable to be applied in rice seedling field, direct seeding field, small seedling, weak seedling and leaky Honda.

Naphthoylchlor: the half-life is as long as 12 weeks. It is effective to apply pesticide at pre-bud or 1-leaf stage after bud. Wheat of Gramineae, leek of Liliaceae, celery, fennel and lettuce of Umbelliferae are sensitive to it.

Paspalum: used in rice fields and decomposes quickly in the soil. It is a highly selective contact herbicide, does not conduct, only works at the contact site, and is only used as a stem and leaf treatment agent. Rice should not be treated with medicine within 10 days before and after spraying, should not be mixed with 2mai 4murd, and should not be used with liquid fertilizer.

Acetochlor: the duration is about 60 days. Keep the shallow water layer for 5-7 days after application, without drainage and no series irrigation. It is suitable for application in plastic film mulching fields, irrigated fields, summer crops and dry fields in the south, to which rice buds are very sensitive.

Butachlor: the residual period is about 60 days. It is effective for weeds before sprouting and 2-leaf stage. The weeding effect was good when the seedling field was used 3 days after sowing, but the weeding effect was general before or after sowing, and it was easy to cause drug damage when used in advance. Water cannot drown the heart of the seedling.

Metolachlor: the effective period is 60-80 days, and it is safe for the following crops. It has no effect on perennial Gramineae weeds and broad-leaved weeds. It is suitable to be used in plastic film mulching fields, irrigated fields, summer crops and southern dry fields, and rice buds are very sensitive to it.

Dibenzoylchlor: long residual period. It takes one year to grow wheat after application, which can only kill the weeds before sprouting.

Phenylthioaclachlor: it lasts for more than 1 month and is used in rice fields. For barnyardgrass special effect, rice transplanting 3-10 days after application, water-retaining layer 3-4 cm, do not apply in the rice seedling stage, especially not in the seedling stage.

Pyrlofenachlor: the half-life of soil is 16-20 weeks, which can control many kinds of weeds in wheat field.