Causes of premature senescence in late growth stage of watermelon covered with plastic film

One is to lose weight. Watermelon generally applied enough base fertilizer, and covered with plastic film, high ground temperature, fertilizer decomposition fast, absorbed by the plant more, so after sitting melon performance de-fatting, leading to premature senility in the later stage. The second is to stay in the root melon. The precocious watermelon generally gives birth to the first female flower at the 7 to 8 nodes of the main vine, when the melon seedlings begin to grow. If the first melon is retained, a lot of nutrition will be consumed, which will affect the growth and development of the melon, and it is very easy to form "small old seedlings". Cause premature senescence and produce small melons. The third is the loss of pick. In the fruiting period of watermelon, the air temperature is high, but the root system of plastic film mulching cultivated melon is shallow, the soil moisture is easy to lose, and the water content is too low, which leads to premature senescence.