大棚黄瓜连作土壤的日光消毒技术效果比较

Comparison of efficacy of successive soil's solar disinfection of continuous cropping of cucumber in plastic covering

【目的】针对大棚黄瓜连作造成的病害问题，筛选出适合西北地区大棚土壤日光消毒的方法。【方法】于2008—07—2008—11，利用大棚夏季休茬的时间，通过覆以不同颜色薄膜以及在土壤中添加不同添加物对棚内土壤进行日光消毒，共设12种土壤消毒处理，测定大棚内气温、地温、微生物数量及杂草种类的变化；以黄瓜和西瓜为消毒后测试作物，测定其出苗率和成苗率。【结果】在整个消毒期内，大棚内气温的日变化为24．9～49．9℃，日均气温为34．5℃；10cm土层日均地温为39．9℃，地温≥40℃时数为6．7h。不同处理对10cm土层的增温效果不同，其中增温效果较好的处理依次为T4（稻壳）、T5（麦糠）、T7（生鸡粪）、T3（石灰氮）和T6（生牛粪），日均地温分别为42．7，41．8，41．2，40．8和40．3℃，其他处理均低于以上5个处理；20cm土层地温日变化与10cm土层一致，但增温效果低于10cm土层。日光消毒对土壤中微生物杀菌效果较好的处理依次为T3（石灰氮）、T7（生鸡粪）和T6（生牛粪），其对细菌、真菌、放线菌的杀菌率分别为95．5％，79．7％，85．3％；94．7％，74．2％，35．1％和93．5％，61．7％，27．6％，使测试作物黄瓜、西瓜的成苗率分别达到94．7％和88．7％，87．3％和84．7％，82．0％和80．0％；经过日光消毒，覆膜处理对杂草有明显的防治效果，不覆膜处理杂草生长量大，且以马齿苋为主，占杂草鲜质量的84．8％。【结论】通过在土壤中施人添加剂且经过日光消毒后，对于黄瓜连作造成的病害问题有明显的防治作用，其中以施人石灰氮和生鸡粪的效果最佳。

【Objective】 Aiming at the disease caused by continuous cropping of cucumber in plastic covering,the study was to sift out soil disinfection methods fit to northwest areas.【Method】 Using high temperature to disinfect the soil of plastic covering in the summer before growing season in 2008-07-2008-11,setting 12 kinds of treatments,different colours of plastic and different functions of additives were adopted to determine the variations of air and soil temperatures,amount of microorganism,and weeds kinds in plastic covering.Cucumber and watermelon were taken as the plants to determine emergence rate and seeding rate.【Result】 In the whole period of disinfection,the change of daily air temperature in plastic covering was 24.9-49.9 ℃ and daily mean air temperature 34.5 ℃;The average temperature in 10 cm soil layer was 39.9 ℃,the average time ≥40 ℃ was 6.7 h.The different treatments had different temperatureincreasing effects for 10 cm soil layer,among them the best treatments were T4 （rice husk）,T5 （wheat bran）,T7 （raw chicken manure）,T3 （nitrolime） and T6 （raw cow manure）;The average soil temperature was 42.7,41.8,41.2,40.8 and 40.3 ℃,respectively,other treatments were not as good;The variation of 20 cm soil temperature had the same trend with the 10 cm soil layer temperature,but temperatureincreasing effect of 20 cm soil layer was worse than that of 10 cm soil layer.The best treatments of sterilization for soil microorganisms were T3 （nitrolime）,T7 （raw chicken manure） and T6 （raw cow manure）;The sterilizing rate of bacterium,fungus,actinomyce was 95.5%,79.7%,85.3%;94.7%,74.2%, 35.1% and 93.5%,61.7%, 27.6%,the rate of plant of the test crop including cucumber and watermelon was 94.7%and 88.7%,87.3% and 84.7%,82.0% and 80.0%;The prevention measures were obvious to kill the weed by solar disinfection;The main weed species was purslane herb,accounting for 84.8%.【Conclusion】 The effects of controlling disease of cucumber caused by continuous cropping were significant after adding different kinds of additives to soil,and the best treatments among them were nitrolime and raw chicken manure.