Biological Control of Meloidogyne Spp. in Cucumber (Cucumis Sativus L.) and Development of the Ecological and Environment-friendly Fertilizer with Pesticides
|School||Nanjing Agricultural College|
|Keywords||Root-knot nematode Biological control Chitosan Salicylic acid Cynanchum Komarocii|
Root-knot nematode(Meloidogyne sp.) was one of the major pathogens damaged the corps and widely spred around the world. More than 80 species of genus Meloidogyne have been reported up to date. They are parasites of more than 2000 hosts, including vegetables, food corps, cash corps, fruit trees, ornamental plants and weeds etc. Plants grew in temperate zone, subtropical and tropical areas were affected severely by root-knot nematodes and yields were normally decreased by 10%-20%, most severely damage would exceed 70%.Based on the theory of plant acquired resistance and the mechanisms of soil eco-biological repairment, the control of root-knot nematode was studied in this paper. The effective immune resistance inducers of root-knot nematode were screened. The plants with antibacterial and insecticide functions, such as the seeds of Sophora alopecuroids L. Cynanchum komanovii and Neem, were grinded to superfine powder as the carriers which were added with plant induced resistance ingredients, trace elements and humic acids. Thus, a multifunctional eco-organic fertilizer with an the integrated functio of nutrition, soil improvement, immune diseases and pests prevention was developed. The filed application technology was integrated in order to satisfy the demand of rural labor with a deft, effortless way to promot the sustainable agricultural development. The results from this study were included as follow:1. The resistance-induced agents of root-knot nematodes were screened and the pathway of immune induced resistance in cucumber root-knot nematodes was created. The chitosan treatment had an inhibition effect to the root-knot nematodes of cucumber. The 150mg/L concentration of chitosan could decrease disease index of root-knot nematode significantly, increase the root growth and the control effect was 28.1%. Exogenous chitosan and salicylic acid had effects of high inhibition and induced resistance to root-knot nematode. Furthermore, chitosan and salicylic acid had synergistic effects. The mixture of 150 mg/L SA+100 mg/L CTS could significantly reduce the disease index of root-knot nematode and the control effect was more than 40% with increasing production by 5.6%.2. The effects of chitosan on the growth of cucumber in greenhouse were studied. The results showed that chitosan could promote the bud differentiation, lower the female flower position, accelerate female flowers bloom, increase the number of female flowers and the ratio of female to male flowers. It also improved the quality of cucumber and increased the yield, which showed a good application prospect.3. Cynanchum komanovii and Sophora alopecuroides L. were obtained after screening the plant resources. The methanol extracts from seeds of Cynanchum komanovii and Sophora alopecuroides were found with a strong toxicity on root-knot nematode, which reduced then number of root-knots and the disease level. The control effect was more than 70%.4. Based on the knowledge accumulated from research in botanical insecticide and fungicide, the technology of plant immune induced resistance and nematode biocontrol were integrated with the consideration of eco-environmental protection, resource utilization, highly economic and effective formulation. The production technology and the usage of quadratic orthogonal rotation were designed. Moreover, a multifunctional eco-organic fertilizer with nutrition and plant protection, together with its production technique and quality control procedures were developed by using residues of a botanical pesticide Kanglvgongchen combined with the superfine powder of neem and Cynanchum komanovii seeds, which was treated as organic carrier of a botanical insecticide and fungicide and adding plant immune agents, humic acid, inorganic nutrients and trace elements,5. The efficacy of eco-organic fertilizer was analyzed. The results showed that the fertilizer increased the cucumber yield and quality, improved the utilization of chemical fertilizer, promoted crop resistance, especially induced resistance to root-knot nematode and bacterial infection. Therefore, the result in this study demonstrated the sustainability in efficient utilization of soil can be improved by significantly reducing the use of toxic chemical pesticides.