Effect Of Precise Management Of Water And Fertilizer On Nutrient Absorption And Growth Of Facility-cultivated Watermelon And Melon

Watermelons and melons are among the top ten fruits in the world and are grown all over the country.In 2018,the planting area of watermelon and melon in China was 150.97and 358.9 million hectares,and the yield was 6302 tons and 12.78 million tons,accounting for 60.64%and 46.76%of the world,s output,respectively,ranking first in both area and yield.The output value of watermelon and melon per unit area is about four times the average output value of China's planting industry,and it is the main industry for the revitalization of many rural villages and poverty reduction.However,with the rapid development of the watermelon and melon industry,due to the relatively weak research on watermelon and melon nutrient absorption laws and precise management systems for water and fertilizer,and the melon farmers generally lack scientific fertilization knowledge and resource environmental protection awareness,farmers,water and nutrient inputs during cultivation If it is used too much,it will not only reduce the yield and fruit quality,but also bring potential environmental risks.In this paper,through field experiments under facility cultivation conditions,the nutrient absorption characteristics of watermelon and melon at different growth stages and the effects of different water and fertilizer on the growth of watermelon and melon were studied,with a view to determining a reasonable recommended fertilizer application amount for watermelon and melon,and formulating a water and fertilizer integrated precision management system Provide theoretical and technical support to reduce fertilizer application and increase efficiency.Through research,the following main results were obtained:?1?The nutrient absorption characteristics of watermelon at different growth stages show that the difference in nutrient demand per unit of economic output of different water and fertilizer treatments is not significant.The average nutrient requirements of N,P₂O₅ and K₂O are 1.42,0.82 and 3.39 kg/1000kg,respectively.More,the proportion of phosphorus and potassium required during the reproductive growth period increased,the average N:P₂O₅:K₂O absorption of watermelon throughout the growing period was 1.00:0.58:2.39;the dry matter accumulation of the watermelon fruit during the expansion period accounted for 78%of the dry matter throughout the growing period,nitrogen and phosphorus,Potassium nutrient carried out accounted for 58%,67%and 71%of the total carried out,respectively,the fruit expansion period is the maximum efficiency period of watermelon nutrition.?2?The nutrient absorption characteristics of melons at different growth stages show that different varieties of Qianyu 6?thin skin?,Xinongxiaozizaomi?thick skin?,and Xizhoumi 25?thick skin reticulated?have nutrients per unit of economic output under fertilization conditions The difference in demand is not significant.The average demand for N and P₂O₅ nutrients is 2.60 and 1.25 kg/1000kg,respectively.The demand for K₂O nutrients Xizhoumi 25 is significantly higher than Qianyu and Xinongxiaozizaomi,Qianyu and Xinnongxiaozizaomi.The K₂O demand for Xinongxiaozizaomi is 5.01 kg/1000kg,and Xizhoumi 25 is 7.27 kg/1000kg.The average N:P₂O₅:K₂O absorption of melon during the whole growth period is 1:0.48:2.16.The amount of nitrogen,phosphorus and potassium nutrients carried out by different varieties in each growth period was the highest in the fruit expansion period,with an average proportion of 55%,58%and 62%.?3?Precise automatic control of water and fertilizer Compared with conventional water and fertilizer,there is no significant difference in watermelon dry matter quality,nutrient content and nutrient carry-out,yield and quality are not reduced,which is 37%less water than conventional water and fertilizer,reducing fertilizer N 46.0%,P₂O₅ 72.0%,K₂O 56%,irrigation water utilization rate increased by 68.0%,and nitrogen,phosphorus,and potassium nutrient utilization rates increased by 3.6,4.4,and 9.1 percentage points,respectively.Formulate integrated irrigation and fertilization system for watermelon water and fertilizer in spring stubble in facilities.?4?The precise control of water and fertilizer under the same variety of melon has no significant difference in dry matter quality,nutrient content and nutrient carry-out compared with conventional water and fertilizer,and the yield and quality have not decreased,which is37.0%less water than conventional water and fertilizer,reducing fertilizer N 65.0%,P₂O₅84.0%,K₂O 68.0%,irrigation utilization rate Qianyu 6,Xinongxiaozizaomi,Xizhoumi 25increased by 59.0%,60.0%,58.0%,Qianyu 6 Potassium nutrient utilization rate increased by3.6,3.5 and 11.1 percentage points respectively.The nutrient utilization rate of early-dense Nitrogen,Phosphorus and Potassium in Xinnong Seeds increased by 3.4,2.8 and 8.4percentage points respectively.The utilization rate of nitrogen,phosphorus and potassium in Xizhou Mi No.25 increased by 3.4,5.9 and 19.2 percentage points respectively.Formulate integrated irrigation and fertilization system for melon water and fertilizer in spring stubble in facilities.