Anhui rapeseed flower period is generally postponed

Anhui rapeseed flower has become a big tourist landscape. According to the comprehensive analysis of the agricultural meteorological conditions since the sowing of rapeseed in Anhui Province in 2010, the current growth of rapeseed and the prediction model of rapeseed development period, it is expected that the general ripening period of rapeseed in Anhui Province in 2011 is: The Jianghuai area was around May 22, and the area along the Yangtze River was around May 18, which was slightly later than normal.

First, the main forecast basis

1. Analysis of agricultural meteorological conditions since sowing

The agro-meteorological conditions during rapeseed sowing and bolting in Anhui Province have more harm than good. The main unfavorable meteorological conditions are that the temperature in January is abnormally low, the extreme minimum temperature below -3 °C lasts for many days, the accumulation temperature of rapeseed is obviously insufficient, and the drought in autumn and winter in the north of Hefei has led to widespread delay in the development of rapeseed. The bolting period was postponed for more than 10 days, and some areas in the south of the Yangtze River were postponed for more than 20 days.

The agrometeorological conditions during rapeseed bolting to flowering are generally favorable. During this period, the main process is mainly precipitation, the soil moisture is basically suitable, the average temperature in the stage is normal and high, and the sunshine is sufficient, which is conducive to the recovery of rapeseed and the transformation of seedlings, which accelerates the development of rapeseed, but there are two cooling in the middle and late March. In the process, the extreme minimum temperature in the main rape producing areas is mostly above 0 °C, and the rape damage is relatively light. Beginning on March 20, Anhui rapeseed blossomed from south to north. At present, the rapeseed along the Yangtze River has been generally flowering, which is about 7 days later than normal; Jianghuai rapeseed has entered the flowering period, and some areas are still in the early flowering stage, about 5 days later than normal.

2. Calculation results of rapeseed development model

According to the calculation results of the flowering-mature prediction model of Brassica napus L. in the Jianghuai District of Anhui Province and the Jiangnan District of Anhui Province, it is estimated that the maturity of the main rapeseed in the Jianghuai region will be on May 23, and along the Jiangnan area on May 19th.

Second, weather trends and production recommendations

According to the forecast of the Anhui Climate Center, the precipitation in the south of the Huaihe River in April 2011 was less than normal, the temperature in the north of the river was slightly higher, and the south of the Yangtze River was close to normal. At the same time, the temperature is wide, and there may be cold weather. According to this suggestion:

1. Spring low temperature frost is the main meteorological disaster during the flowering and knotting period of rapeseed. In April, the temperature will change greatly, and there may be cold weather. Therefore, all localities should pay close attention to the weather changes and adopt anti-frost measures such as smoke before the arrival of cold air. To reduce or avoid low temperature frost to cause loss of yield to rapeseed.

2. After the temperature rises, the weather conditions of high temperature and high humidity are conducive to the development of pests and diseases in spring, and all localities should strengthen the prevention and control of rapeseed pests and diseases. In particular, we must do a good job in the prevention and control of rapeseed sclerotia.

3. The middle and late May is the key period for rapeseed harvesting. The rapeseed production area should pay attention to the weather information, and grab the sun in time to avoid the impact of disasters such as “bad rain” on rapeseed harvest.