Research On Efficient Watermelon Production Technology Based On The Fertilizer Demand Law And Plant Growth Regulator

Watermelon is an important horticultural crop world wildly.China,the biggest watermelon producer and consumer,who expend much more fertilizer per unit area during watermelon production,as well as show much lower fertilizer utilization rate than those in developed countries such as the United States.Nowadays,improper use of chemical fertilizers has become an important factor of ecological problem such as soil compaction and water pollution,which is also a hot issue to be solved in the watermelon industry in China.In order to promote the high-quality and sustainable development of watermelon industry in China,we try to develop fertilizer efficient utilization technology based on the law of fertilizer demand in the whole growth period of watermelon.Besides,this study also explored the enhanced function of a environmentally friendly plant growth regulator on the fertilizer utilization during watermelon production.The main results are as follows:1.A fertilizer reduction and efficiency enhancement technology was established based on the law of fertilizer demand in the whole growth period of watermelon.It was found that T1-T3（N and P₂O₅ decreased by 56.25%-68.75%,K₂O decreased by34.37%-53.12%）treatments did not result in watermelon growth weakening or element deficiency in the vegetative growth,but improved the flowering and fruit-setting ability of watermelons.In addition,treatments improve the soil nutritional status and the soil fertility by increasing the activities of soil urease,neutral phosphatase,sucrase and catalase in different degrees.Among them,the best fertilization treatment T2 is the most suitable for small-fruit watermelon production in protected cultivation in early spring facilities.In this scheme,the use of N,P₂O₅ and K₂O is reduced by 62.5%,62.5%and 43.75%respectively,while the fruit quality,yield and price are enhanced as compared with the control.Finally,T2 treatment result to an increased yield of 13.31%（2725.08 kg/mu）,as well as rising incomes of27.45%（18596 RMB/mu）.2.N-diethylaminoethyl hexanote（DA-6）,an environmentally friendly plant growth regulator,was employed to promote watermelon production.It was found that,application of 200mg/L DA-6 before flowering and the second female flower significantly reduced the foliar nitrogen content even though it showed no significant effect on the vegetative growth and flowering of the plant.In addition to,application of DA-6 was found to increase the setting rate by 16.67%and yield by 28.44%,but do not affect the fruit quality.In this thesis,we established a set fertilizer reduction and efficiency enhancement technology based on the law of fertilizer demand in the whole growth period of watermelon,as well as preliminarily explored the use of DA-6 during watermelon production.Our findings provide reference and technical support to reduce the use of chemical fertilizers,which will help us to establish a safe,environmentally friendly,efficient and economical watermelon industry.