The causes and remedial measures of the latest yellowing of rape seedlings

Rapeseed has always been an important oil crop and cash crop in China. It has a long history of planting, and September is the season for planting rape in southern China and the Yangtze River Basin. However, many rape growers often encounter the phenomenon of yellow rape seedlings, so what is the cause of this? How do we solve it? Let's get to know each other.

1. Causes of yellow rape seedlings

Yellowing of rape seedlings is generally caused by three conditions: one is that rape is not ploughed before sowing, rape sowing generally needs to be ploughed twice before sowing, the first time to carry out deep ploughing of large soil, then drying soil for a week, the second time to plough when sowing, then to be fine, and to apply sufficient base fertilizer before ploughing. The second case is because the previous crop is broad bean field, the residual pathogen is larger, because the disease of broad bean occurs is larger, the pathogen will remain in the soil after harvest, causing harm to rape seedlings. The third is that there is no pest control, resulting in the aggravation of the disease, resulting in yellow seedlings.

II. REMEDIATIVE MEASURES

1, in the seedling stage to do a good job of ditch drainage, avoid ponding phenomenon, at the same time to do a good job of timely sowing preparation, rape is more sensitive to the response of sowing time, rape germination and rooting long leaves need certain temperature conditions. The germination temperature is 16-22 degrees, and the leaves need to be above 10-15 degrees to proceed smoothly. It is recommended to select fertile soil and plots close to water sources.

2. Spraying foliar fertilizer on rape. It is suggested to spray 0.1-0.3% potassium dihydrogen phosphate or potassium phosphate on leaves to promote root growth and development of rape seedlings and restore yellowing phenomenon as soon as possible. In terms of topdressing, nutrients should be supplied in time according to the growth of rape, and phosphorus and potassium fertilizer should be appropriately applied to greatly reduce the yellowing phenomenon.

3. Proper trimming and tipping can promote more branches of rape, form excellent population structure, enhance disease resistance, effectively prevent rape yellowing phenomenon, and is also one of the ways to obtain high yield.

4. Timely prevention and control of pests and diseases is also one of the main measures to prevent yellowing of rape seedlings. In the growth cycle of rape, the main pests and diseases that will be received are cabbage worm, jumping beetle, aphid, etc. It is suggested that 25% dichlorodil 3000 times solution or 40% dimethoate 1000 times solution can be used for spray prevention and control.

The above is an introduction to the causes and remedies of rape seedling yellowing. I hope it can help you. If you want to know more about it, please pay attention to us.