What to Do About Early Bolting and Early Flowering in Rapeseed? A Detailed Guide to the Latest Solutions
Rapeseed is a fairly common vegetable, generally distributed across the Yangtze River basin. When growing winter rapeseed, the time for bolting and bud emergence is generally in February to March. If it bolts and flowers before the Spring Festival, then this is the phenomenon of early bolting and early flowering in rapeseed. The phenomenon of early bolting and early flowering can have a major impact on rapeseed yield. So what should be done about early bolting and early flowering in rapeseed? Below, the editor will give you a brief introduction. Let's take a look!
1. Preventive Measures
1. Water and Fertilizer Management
When planting rapeseed in autumn and winter, we must pay attention to doing a good job of watering. Whether transplanting or direct seeding, if the soil is too dry, it is very unfavorable to the growth of rapeseed. Therefore, water timely to combat drought and promote the rooting and leaf growth of rapeseed seedlings. If the temperature is too low in winter, then winter irrigation should be carried out in time, which can replenish moisture while also maintaining soil temperature. For some rapeseed seedlings with weaker growth, urea should be applied early to promote the seedlings' growth into strong plants, and this can also prevent the occurrence of early bolting and early flowering. On the contrary, strong seedlings do not need topdressing, to avoid excess nutrients accelerating the growth rate of rapeseed.
2. Chemical Regulation
When rapeseed is at the 4-leaf stage, bolting stage, early flowering stage and other periods, these are key periods for controlling excessive growth in rapeseed. We can choose growth regulators such as paclobutrazol and uniconazole for chemical regulation. When planting rapeseed, if the sowing time is too early or if excessive growth causes the rapeseed to show early bolting and early flowering, then a growth regulator should be diluted with water and sprayed, and it must not be sprayed again excessively or missed. The best time to spray the growth regulator is before overwintering. This can not only prevent the occurrence of early bolting and early flowering in rapeseed, but also improve the cold resistance of rapeseed.
2. Remedial Measures
1. Remove the Bolting Stems in Time
When the early bolting stems of rapeseed have grown to about 15-20 cm, remove the bolting stems. Remove about 8 cm from the tip of the bolting stem. According to the growth habits of rapeseed, if the tip of the bolting stem is removed, the growth process of rapeseed can be delayed by about three weeks. Moreover, because rapeseed has very strong branching growth, removing the bolting stems will not affect yield and can even increase yield. Do not remove bolting stems on rainy days; it should be done on sunny days. After removing the bolting stems, disinfect appropriately to speed up wound healing, and fertilize appropriately. Then spray foliar fertilizer in the later growth stage to ensure normal growth of rapeseed.
2. Fertilize Appropriately
When rapeseed has bolted very tall or has already flowered, then it is generally not recommended to remove the bolting stems again. At this time, after the Major Cold solar term has passed, phosphorus and potassium fertilizer should be sprayed appropriately to strengthen the growth vigor of rapeseed. If the rapeseed variety being grown is double-low rapeseed, then we should also pay attention to supplementing boron fertilizer well. This is because this variety is very sensitive to changes in boron, and it should be done at the bolting stage and early flowering stage to meet the boron demand of rapeseed.
The above is a brief introduction to what to do about early bolting and early flowering in rapeseed. That is all for today's introduction. This article is for reference only, and we hope it can help everyone!