At present, rapeseed in the southwest region has gradually twitched and blossomed. The rapeseed is in the period of budding in the middle and lower reaches of the Yangtze River and is an important period for the formation of yield. Since the beginning of spring, low temperature, rainy weather, and low-light weather have appeared in the Yangtze River Valley, causing rape to spring up late in the spring and sending trees slowly. The growth period has been postponed by 5-7 days. In order to seize the summer oil harvest this year, we must seize agricultural time, effectively respond and promote scientific disaster prevention. Specially put forward technical advice on field management in the middle and later stages of rapeseed.
(i) Clearing the ditch in time to increase temperature and reduce stains. This year, there are many low-temperature and rainy days in the spring, especially if the rainfall is relatively large recently, we must seize the weather to clear the gap and clean up the trenches in time to ensure the smooth flow of the “three channels†so that there will be no dark stains on the plowed land and there will be no clear water in the ditch to prevent stains. Harm, increase soil temperature, promote rape growth and development. Qinggou's soil is cultivated in the side of the rapeseed to improve the lodging resistance of rapeseed.
(B) to strengthen monitoring, prevention and control of pests and diseases. The early flowering period is an important juncture for the prevention and control of rapeseed sclerotinia. At present, rapeseed has entered the Leidai period in most areas and is about to enter the early flowering period. The rapeseed grows vigorously and the fields are poor in air and light, and after the temperature rises, Sclerotinia becomes more susceptible to outbreak. All localities should strengthen forecasting and guidance and guide farmers in the prevention and treatment of Sclerotinia and Sclerotinia after weather is fine. The specific method is to use 40% sclerotia net 100-200 g per mu or 50% carbendazim wettable powder 100-200 g watered 50 kg, which is generally controlled once in the early flowering period of rapeseed. Prevention once.
(3) Control and promote the combination of scientific fertilization. Spring is a period of rapid growth of rapeseed, but also the peak season for fertilizer, according to the timely situation of the seedlings, appropriate amount of topdressing, growth of vigorous plots to control the application of nitrogen fertilizer, topdressing phosphorus and potassium fertilizers. For the poor growing and late sowing plots in the lower reaches of the Yangtze River, 2-3 kilograms of urea and 5 kilograms of potassium chloride per acre can increase the number of branches, flower buds, and seeds of each pod and 1000-grain weight. Boron fertilizer is applied as early as possible to fields with less or no boron application. In view of the delay in the growth period of rapeseed this year, all localities must carry out “one spray and three defenses†during the flowering period. The application amount per acre can be sprayed with 200 grams of potassium dihydrogen phosphate, 100-200 grams of carbendazim, 50-100 grams of speed music boron (effective boron content ≥ 20%) watered 50 kg. Promote growth, prevent premature aging, prevent sclerotia, and prevent high temperatures.
(D) timely harvest, stacking after cooked. Oil rice and dry land canola are relatively loose during the agricultural season. They must be harvested when 80% of all rape plants in the field turn yellow, and are stacked in the land or in the dam for 5-7 days. After full ripening, they are selected for fine weather threshing to increase oil content. . The one-time mechanically harvested rapeseed should be carried out after the pods have completely yellowed. In order to maintain timely rice transplanting and transplanting rice in the oil-bearing rice region, it can be harvested when the whole field Liucheng rape is yellow (2-3 days ahead of normal maturation). The rapeseed can be cut from the lower part of the plant and stacked on the field side or in the field. (The pod layer is placed upwards) and covered with a film for 3-4 days before spreading out to dry, accelerating postcooking of rapeseed, increasing grain weight and oil content.