Effect Of Summer Catch On Soil Enzyme Activity And Soil Trait Of Cucumber

As vegetables production scale, specialization, the speeding up of SheShiHua development, result in continuous cropping vegetable growing area, caused the serious soil quality degradation, soil nutrient imbalance, plant diseases and insect pests, microbial population structure imbalance, which led to the decrease of the yield and quality of vegetables, seriously hindered the development of vegetable production, facility vegetable continuous cropping obstacle has become the primary problem of the sustainable healthy development of vegetable industry in our country.Cucumber (Cucumis sativus1.) alias wang melon, cucumber, belong to the gourd family cucumber annual herbaceous plants, fruit combination, can be the anniversary production and supply of high yield of vegetables, is one of main melons as in our country, the common culture, has a long history. Vegetable production is one of the protected area in the cultivated area is one of the largest vegetable crops, as well as continuous cropping obstacle serious crop.Although the causes of continuous cropping obstacle is more, but the main reason from the soil.Continuous cropping obstacle is the same crop or relatives crop after continuous cropping, even under the condition of normal cultivation management, can also lead to lower yield, poor quality change, growth and development status of inferior quality.The causes of continuous cropping obstacle is very complex, it is plants, soil, and the result of the interaction among the microorganism.Its general main thought is based on the following aspects:plant released allelochemicals, the accumulation of soil borne pathogens, the change of soil microbial community structure and the change of soil physical and chemical properties and soil nutrient consumption.The study of continuous cropping obstacle is more at home and abroad, and put forward a lot of can play a good role in the production of prevention and control measures, such as "associate" and "catch" cultivation and application of resistant varieties, soil disinfection and reasonable fertilization, such as biological control measures, but so far, the real cause of continuous cropping obstacle or dominant factor has not yet been determined.Since the toxic substances belong to allelopathy.Allelopathy is by H.M oHsch professor for the first time in1937, is refers to the plant in the process of growth and development, through the release of certain chemicals on the surrounding environment of other plants or microorganisms inhibit or promote role, to protect their own growth, the allelopathy is widespread in nature.And since the poison effect is a kind of special function of allelopathy, occurred within the kind of between the effect of growth inhibition.Since the toxic effect of production mainly includes the volatile, plant aboveground leaching, commend root secretions and plant residual decay, and so on, through this a series of ways to release the material will be the same or next crops are of the same or different kinds of crops to produce inhibition.Plant residue Ren decomposing approach, after harvesting the crops, used for covering with rice straw and in the field of residue after the rain of leaching and microbial decay, will release a great deal of allelochemicals, under the influence of the growth of crop.Based on the soil of continuous cropping cucumber as the research object, to Sudan grass, rye, wheat, basil, sage, and Chinese cabbage as fill idle plant, using the traditional way to measure the cucumber plant height, fresh weight, dry using high performance liquid chromatography (HPLC) method to analysis the phenolic acids material type and content in the soil, and explores in northeast China catch PengShi soil, the influence of continuous cropping cucumber and select appropriate fill idle plants, and provide a basis to keep continuous cropping cucumber soil health.The main results are as follows:1, after to catch the crop of the cucumber plant height and dry weight determination, you can get, summer catch can significantly increase the crop of the cucumber plant height, dry weight and fresh weight.Each fill idle processing can effectively improve the cucumber plant height, dry and fresh weight, of which the most catch Sudan grass processing.This rotation with catch belongs to a kind of short cycle, and has carried on the straw returned, improved the various aspects of soil properties have a direct relationship.2, after to catch the crop of the cucumber root area, the determination of soil physical and chemical properties, can be obtained, by filling in spare can significantly reduce the soil EC value, alkali solution nitrogen, rapidly-available potassium content in soil, of which the most catch Sudan grass significantly.Increased soil available p content, in order to catch the most significant of wheat.That catch can effectively slow the enrichment of potassium and nitrogen in the soil, reduce soil salt accumulation, slow down the occurrence of soil secondary salinization.3, through determination of soil enzyme activity, found that catch for the change of soil enzyme activity have a significant impact.The possible reason is that, fill idle plant root secretion, decomposing and produce allelochemicals, or because they changed the proportion of the carbon source in the soil, caused the significant change of soil enzyme activity.Catch can significantly change the soil enzyme activity, in which wheat to changing soil urease activity effect is obvious.Rape to changing soil polyphenol oxidase activity.Sudan grass for change dehydrogenase and catalase activity.4, based on the influence of soil phenol acids material type and content, research shows that after harvesting the crops, used for covering with rice straw and in the field of the residue after the rain of leaching and microbial decay, will release a great deal of allelochemicals, under the influence of the growth of crop.Study found, sorghum, corn, oats and wheat residue decomposing and fluid contains a large number of phenolic acids material, fill idle plants decay in this test, is the main reason for the increase soil phenolics.Summer catch all kinds of crops increased the kinds of phenolic compounds content in soil, including rye and wheat to increase the effect of phenolic acids matter content in soil is more noticeable.To sum up, the summer catch for continuous cropping cucumber growth and soil ecological environment has a significant effect, can significantly promote the crop of the cucumber plant height and fresh weight, dry change of soil physical and chemical properties, change the soil enzyme activity, and increase the content of phenolic acids substances in soil.For different fill idle plants, for the influence of various aspects index also each are not identical, but the comprehensive comparison, catch Sudan grass to improving the effect of cucumber growth and soil environment are higher than other fill idle plants.