向日葵空壳率一般在30%左右,甚至多达50%以上,其主要原因是授粉不良。人工授粉可以提高向日葵结实率。人工授粉时间是在整个田块有70%植株开花后的2—3天,进行第1次授粉,以后每隔3—5天进行1次,共进行2—3次。授粉应在上午7—8时到11时之间进行。因中午天气炎热,花粉生活力弱,授粉效果不好,因此如上午未授 Sunflower shell rate is generally about 30%, or even up to 50% or more, the main reason is poor pollination. Artificial pollination can improve sunflower seed setting rate. Artificial pollination time is 70% of the plants in the field after blooming 2-3 days, the first pollination, after every 3-5 days 1, a total of 2-3 times. Pollination should be carried out between 7 am and 11 am in the morning. Due to the noon hot weather, pollen vitality is weak, pollination is not good, so the morning did not grant