Management opinions on the later growth stage of High-yielding rapeseed by preventing Disease and waterlogging during farming

At present, rape has entered the flowering stage, so we must grasp the agricultural season, deal with it scientifically, prevent diseases and stains, ensure high yield, and conscientiously implement the field management techniques in the later stage of rape.

Prevention and control of rape diseases and insect pests

1. Do a good job in clearing ditches and regulating water. There are many low-temperature, cloudy and rainy days in spring, especially in the flowering period, with heavy rainfall. Seize the weather clearance and clean up the field ditch system in time to ensure that the "three ditches" are smooth, so that there are no dark stains in the plough layer and no clear water in the ditch, so as to prevent waterlogging damage and increase soil temperature. Promote the growth of rape. The soil of clear ditch was cultivated on the side of rape row to improve the lodging resistance of rape.

2. Strengthen the prevention and control of diseases and insect pests. The early flowering stage is the key period for the control of Sclerotinia sclerotiorum in rape. According to the investigation, Sclerotinia sclerotiorum has occurred sporadically on leaves, with an average incidence rate of 0.23% and a maximum of 0.84%. Downy mildew, the average rate of diseased plants is 1.6%, the highest is 5.0%; the average number of aphids is 180, the highest is 400. Part of rape grows vigorously, and the ventilation and light transmission in the field is poor. After the temperature rises, Sclerotinia sclerotiorum is easy to break out. It is necessary to strengthen field investigation, and 100-200g 40% Sclerotinia sclerotiorum or 100-200g carbendazim 50% wettable powder can be sprayed with 50 kg water.

3. Apply flower fertilizer seriously. Spring is the rapid growth period of rape, so it is necessary to strictly control the application of nitrogen fertilizer, increase the amount of phosphorus and potassium fertilizer, and apply boron fertilizer as early as possible for the fields with little or no boron application. The general mu is sprayed with 200g potassium dihydrogen phosphate, 100g carbendazim, 50ml 100g ≥ boron (effective boron content 20%) and 50kg water to promote growth, prevent premature senility, prevent Sclerotinia sclerotiorum, and increase grain weight.

4. Timely scientific harvest. Oilseed rice and dryland rape are relatively loose in farming season. Harvest 80% of the rape in the whole field when it is loquat yellow, and pile it up in the ground or in the sun for 7 days. After full ripening, threshing in fine weather is selected to increase the oil content. Rape harvested mechanically at one time should be carried out after the pods are completely withered and yellow. In order to plant rice seedlings with stubble in time, rape can be harvested when 60% of the rape is loquat yellow (3 days earlier than the normal maturity), cut down from the middle and lower parts, stacked on the edge of the field or in the sun (pod layer up), and covered with film for 4 days, spread out to dry, accelerate rapeseed ripening, increase 1000-grain weight and oil content.