Effects Of Different Microbial Fertilizer Treatments On Cucumber Growth And Bacterial Stem Soft Rot

Cucumber,as an important vegetable crop,is widely grown in China.Shandong is one of the main production areas.The obstacle of continuous cropping of cucumber caused by irrational fertilization is becoming more and more serious nowadays.Cucumber bacterial stem soft rot has a long incubation period and is difficult to control once it comes on,which has occurred in a large area in northern China in recent ten years.Microbial fertilizer can improve soil environment,enhance root vitality and plant disease resistance.Based on the biological control of cucumber bacterial stem soft rot,the pathogen causing cucumber bacterial stem soft rot was identified,and the effects of microbial fertilizer on cucumber growth index,physical and chemical properties of soil and incidence of cucumber bacterial stem soft rot were studied.It provides data support for the extensive application of microbial fertilizer.The main findings are as follows:1.The pathogen causing cucumber bacterial soft rot in Jiyang area was identified.Samples were taken in cucumber greenhouses in Jiyang District of Jinan city in May and June2020.Through morphological,physiological and biochemical identification and molecular biological identification,the pathogen causing the disease was identified as Pseudomonas syringae pv.Lachrymans(Psl).2.The growth of the three treatments with microbial fertilizer was significantly better than that of the control group,which mainly showed that the plant height,stem diameter,leaf number,leaf chlorophyll content,plant dry and fresh weight and yield of cucumber were significantly improved.The average yield per mu of each treatment with microbial fertilizer increased by 10.89%,12.96% and 7.83%,respectively,compared with the control group.3.The physical and chemical properties of soil were improved in three treatments with microbial fertilizer.In addition,the organic matter content and the electrical conductivity,soil available p,soil available K,soil total P and soil total N contents increased significantly in the treatment of microbial fertilizer,while soil p H value did not change significantly.4.The incidence and disease index of bacterial soft rot of cucumber stem in three treatments with microbial fertilizer were decreased obviously.By investigating the incidence of cucumber bacterial stem soft rot in the shed,we found that the incidence of cucumber bacterial stem soft rot was reduced by 15.90%,17.97% and 10.88% respectively in three treatments of microbial fertilizer in April.