小麦、毛苕子与黄瓜轮作对土壤微生态环境及产量的影响

EFFECTS OF ROTATIONS OF CUCUMBER WITH WHEAT AND HAIRY VETCH ON SOIL MICRO-ECOLOGICAL ENVIRONMENT AND ITS YIELD

采用常规方法及PCR-DGGE技术对土壤速效养分含量、土壤酶活性和微生物群落结构多样性以及黄瓜产量进行分析,以探究小麦、毛苕子与黄瓜轮作对黄瓜土壤微生态环境及产量的影响。结果表明,不同轮作处理均显著地提高了黄瓜产量,有效地改善了土壤微生态环境。其中小麦-黄瓜轮作黄瓜产量极显著高于对照(p<0.01),增产28.04%,其多酚氧化酶、过氧化氢酶及脲酶活性总体较高。毛苕子-黄瓜处理增产16.78%,并增加了土壤养分含量,转化酶活性较高,极显著高于对照(p<0.01)。DGGE结果表明,轮作有助于根际土壤细菌种类的增多及结瓜后期真菌种类的减少,其中毛苕子-黄瓜处理的影响更为明显。小麦-黄瓜轮作对土壤真菌与定植后30 d土壤细菌群落结构具有一定的影响。总之,小麦、毛苕子与黄瓜轮作有利于缓解黄瓜连作障碍,改善土壤微生态环境,提高黄瓜产量。

Soil available nutrients, enzyme activities, microbial community diversities and cucumber yield in a field under crop rotations of cucumber with wheat or hairy vetch were investigated with conventional methods and PCR-DGGE to study the effect of the rotation on soil micro-ecological environment and yield of cucumber. Results indicate that the rotations significantly increased cucumber yield and effectively improved soil micro-ecological environment. The rotation of wheat-cucumber increased the yield of cucumber the most signifi- cantly （p 〈 0.01 ） , by 28.04% , and improved the overall activities of polyphenol oxidase, catalase and urease. The rotation of hairy vetch-cucumber increased the yield of cucumber by 16.78% and improved the contents of soil available nutrients, and the invertase activity significantly over CK （p 〈 O. O1 ）. DGGE analysis shows that the rotation helped increase the diversity of bacterial community in the rhizosphere, while decrea- sing that of fungi at the late fruit-bearing stage. The effect of the rotation of hairy vetch-cucumber was more sig- nificant. The rotation of wheat-cucumber showed certain effect on rhizosphere soil funged and bacterial commu- nity structures 30 days after transplanting of cucumber. To sum up, the rotations of cucumber with wheat and with hairy vetch help mitigate the cucumber soil sickness, improve the soil microbial eco-environment and raise the yield of cucumber.