To explore the effects of substrates prepared with kitchen waste compost fermented by different species of Bacillus on culture of cucumber seedlings,the fermentation solutions with Bacillus subtilis(T1),B.amyloliquefaciens(T2)and B.velezensis(T3)were watering into the seedling substrates in indoor cavity trays,with water only as control(CK).And then three aspects including growth of cucumber seedlings,chemical properties of the substrates after seedling development and number of pathogenic bacteria were inves-tigated.The results showed that all the three Bacillus species performed well in growth promoting,among which,B.subtilis and B.velezensis were the best in improving chlorophyll content,leaf area,above-ground fresh weight and above-ground dry weight;but they had no significant promotion effect on the the traits of un-derground part especially root length.Comprehensive evaluation with the strength index of seedlings and by membership function method showed that higher strength index of seedlings was obtained when treated with B.subtilis and B.velezensis,and the highest average degree of membership appeared in B.velezensis group,indi-cating the best growth promoting effects of B.velezensis on cucumber seedlings.No obvious effect on pH of the substrates was detected among the three Bacillus species,but the EC of the substrates raised significantly.At the same time,no significant decrease in the Na+and Cl-contents were caused in the substrates treated with the three Bacillus species.In terms of nutrient contents of the seedling substrates,the contents of alkaline dis-solved N and fast-acting K increased significantly under the three Bacillus treatments compared to CK,and the contents of effective phosphorus and organic matter were significantly lower under B.velezensis and B.amyloliq-uefaciens treatments,respectively,compared with the other treatments.All the three species of Bacillus showed significant growth-promoting and disease-preventing effects on cucumber seedlings in the substrates prepared with kitchen waste compost,and B.velezensis showed the best.It was recommended that further research should be carried out to solve the problem of salt ions in kitchen waste compost remaining in the substrates or soil.
关键词
芽孢杆菌/餐厨堆肥/育苗基质/壮苗指数/黄瓜
Key words
Bacillus spp./Kitchen waste compost/Seedling substrate/Strength index of seedling/Cu-cumber