Recent snowfall and low temperature freezing have had a significant impact on the planting of oilseed rape, especially some of the early-sown oilseed rapeseed that has been sprouted, which has suffered obvious frost damage, manifested as leaf wilting, stalk waterlogging, and even the whole plant dying. In order to reduce disaster losses, we should keep in mind the following technical points for disaster resistance and loss reduction.
1. Reduce agricultural operations and avoid physical damage
Before the snow melts, the stalks of canola become brittle and break easily. Therefore, agricultural practices in the field, especially those that may touch the stalks, should be minimized to avoid aggravating the injury. Oilseed rape has a certain recovery capacity, and it is recommended to take corresponding management measures according to the actual damage after the temperature rises.
2. Classified management to promote the recovery of rapeseed
For the fields that are severely frosted and the stems are cracked or broken, when the temperature rises above 0, the sprouts should be picked in time on a sunny day, which is conducive to the rapid growth of the base axillary buds. For fields with light frost damage, when the temperature rises to more than 5, growth regulators such as brassinolide and neoamericans should be sprayed in time to promote the recovery of rapeseed.
3. Clean the ditches and reduce the humidity in the field
The budding stage is the most sensitive stage for rapeseed to water, and it is also the period when its root system grows rapidly. In order to ensure the normal growth of rapeseed, the water content in the field should be controlled at 70-85%. Prolonged flooding can lead to a reduction in rape yield of more than 50%. Therefore, it is necessary to clean up the "three ditches" in time to ensure smooth drainage and reduce the occurrence of diseases.
Fourth, adjust the fertilization strategy to increase yield and resist lodging
After rape enters the budding stage, excessive application of nitrogen fertilizer should be avoided to prevent late ripening. For the fields with obvious frost, about 5 kg of urea and 3 5 kg of potassium chloride can be applied per mu, which can not only help the recovery of rapeseed growth, but also improve its lodging resistance in the later stage, thereby increasing the yield.
Fifth, timely implementation of "one promotion and four prevention" measures
Within one week after flowering, the steady growth of rapeseed was promoted by spraying foliar fertilizer, fungicides, growth regulators, etc., and to prevent sclerotinia sclerotinia disease, flowering and fruiting, premature senescence and high temperature ripening.
Following the above technical points, it is expected to minimize the impact of low temperature freezing on oilseed rape fields, and ensure the healthy growth and stable yield of oilseed rape.
Editor: Shao Shuai.
Proofreading: Li Yunfei.
Second trial: Zhao Min.
on the Internet).