Preventing weedy fields in rice fields
Eye dishes, also known as cutting board buds, drifting, Yunnan farmers called dental grass. The Eyelids is a perennial aquatic herb that is a vicious weed that is damaged by rice. It can be propagated through rhizomes and seeds. Due to the strong viability of the grass, manual removal eliminates labor and time-consuming and poor results. It is difficult to achieve the intended purpose of increasing grass production, especially breeding of eye-catching vegetables in cold-waterlogged fields and winter fields. The output and quality of the plant will be reduced by more than 30%. The use of chemical agents for prevention and control has the advantages of high efficiency, low cost, time saving, and labor saving. As long as the technology is properly controlled and pesticides are applied in a timely manner, the desired purpose of killing weeds without damaging the seedlings can be achieved. The use of chemical fertilizers can save 5-10 labors per mu and increase production of rice by more than 10%. It also has good control effects on other perennial weeds such as wild arrowhead, tetraphylla, and water sponge. First, the spraying period and methods: Usually in the period from the peak to the end of rice tillering (20-30 days after planting), dental grasses are almost equal, and most leaves are the best period for applying pesticides when the color changes from brown to green. Therefore, timely and accurate application of drugs is the key to ensuring efficacy. The application of pesticides is done by means of a shallow water layer of toxic soil, and the shallow water layer is kept 7-8 centimeters within 7-10 days after application, and no “race horse water†can be placed. If Tianshui is dry, it can be slowly added. Within 15 days after application, the field should not be allowed to stir mud or thin grass, nor should the ducks fall into the field, so as to avoid phytotoxicity. Second, the selection and dosage of pesticides: Each dose per acre, can be arbitrarily selected one of the following, but should pay attention to the valley in the valley below 1,500 meters above sea level, the dosage should be reduced as appropriate, take the lower limit number (ie the minimum amount). 150% of Weiluosheng (Doucaojing) EC 100-150ml; 250% of Praxanthine WP 70-90g or 25% Diuron Wettable Powder 70-90g; 378.4% Putian net emulsifiable concentrate 200-250 ml; 450% of Praxanthine net wettable powder 50 g, plus 50% of herbicidal oil 150 g; 550% of Praxanthine wettable powder 50 g, plus 26% of diuron Wettable powder 50 grams. Any of the above herbicides can be spread uniformly with 30-40 kg of fluvo-aquic soil. In addition, the following methods can also be used after rice harvest to reduce the damage of dental grass to rice in the second year. (1) After rice is harvested, drain the field water and immediately use 25% diuron (or 50% of paracetamol) WP and 200 g of water 50 kg to evenly spray the dental grass, and keep it in the field after spraying. 4-5 days without water, and then plow the normal wheat, rape and other spring crops. If the rice piles of broad bean and green manure are not plowed, the weeding effect will be slightly worse. However, the interval between application of pesticides to planting spring crops needs to be more than one month. (2) After harvesting rice in winter paddy field, use 25% of diuron or 50% of protocatechue WP for 200g, mix fine soil with 30kg of wet soil, apply the pesticide in shallow water layer, or drain After field water, 50 kg of water was evenly sprayed on the eyes, and water was stored every 7-10 days. The control effect was good.