Abstract: In order to explore the suitable techniques for reducing nitrogen input,increase efficiency improvement and improve soil microecology for summer maize production in lime concretion black soil,the effects of intercropping green manures on maize yield,dry matter accumulation,soil microbial biomass and microbial community of lime concretion black soil was examined under reduced nitrogen fertilizer input.A field experiment including 6 treatments:No fertilizer control (CK),normal nitrogen fertilizer (100%N),30% nitrogen reduced (70%N),30% nitrogen reduced plus Dolichos lablab intercropping (70%N+LA),30% nitrogen reduced plus Vigna unguiculata intercropping (70%N+J) and 30% nitrogen reduced plus Vigna radiata intercropping (70%N+LV) was carried out in the South of Henan Province,a lime concretion black soil region. The maize grain yield,total dry matter mass and soil microbial biomass carbon and nitrogen content were analyzed. The dynamics of soil bacterial community structure was evaluated by Terminal-restriction fragment length polymorphism (T-RFLP) analysis. The results showed that nitrogen reduction plus 3 green manure can't significantly decreased maize grain yield above ground,and 70%N+LA and 70%N+J treatments significantly increased total dry matter mass compared to 70%N treatment. Significantly higher microbial carbon contents were observed in the 70%N+LA and 70%N+J treatments than that in the 100%N and 70%N treatments(P <0.05). Compared with 100%N treatment,nitrogen reduction plus green manure (70%N+LA and 70%N+J) decreased soil Shannon index,and significant decreases were detected in 70%N+LA treatment and 70%N+J treatments under restriction endonuclease of Hae Ⅲ and Msp Ⅰ,respectively. The principal component analysis indicated that 70%N+LA and 70%N+J treatments had higher similarity on bacterial community structure.

Key words: Green manure intercropping, Nitrogen reduction, Lime concretion black soil, Microbial biomass, Bacterial community

CLC Number: 

• S143.1

• S551