Increase phosphorus availability from the use of alfalfa (Medicago sativa L) green manure in rice (Oryza sativa L.) agroecosystem.
Alfalfa is a good green manure source, but its effect on rice growth has not been fully elucidated. Two green manure species, alfalfa and broad bean (Vicia faba L.), and two N fertilizer levels, alone or combination, were applied to a rice field. The results indicated that alfalfa had more pronounced effects on increasing soil labile phosphorus (P) fractions (including NaHCO3-Pi, NaOH-Pi), P uptake and soil enzyme activities (dehydrogenase, urease, acid phosphatase and β-glucosidase) than broad bean and N fertilizer. The transformation of NaHCO3-Po to labile P regulated by alfalfa played a significant direct and indirect effect on grain yield. Although a much lower N input from alfalfa addition, a similar grain yield with N fertilizer treatment was achieved, and the integration of alfalfa with N fertilizer produced the highest grain yield and P availability, which was associated with the highest urease, acid phosphatase and β-glucosidase activity in soil. These results indicate that alfalfa green manure had a great ability of increasing grain yield through enhancing P availability in rice paddy, which could give us a way to reduce N fertilizer application by enhancing P availability.
School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.|Research Center for Karst Wetland Ecology, Guizhou Minzu University, Guiyang 550025, P. R. China.
Xiaoye
X
Gao
School of Biology Science, Heze University, Heze 274015, P. R. China.
Dongyan
D
Shi
School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Aimin
A
Lv
School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Shengyin
S
Wang
School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Shili
S
Yuan
School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Peng
P
Zhou
School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.|Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Shanghai, P. R. China.
Yuan
Y
An
D000383:Agriculture; D008372:Manure / Q000032:analysis*; D000455:Medicago sativa / Q000737:chemistry*; D009584:Nitrogen / Q000378:metabolism; D012275:Oryza / Q000254:growth & development* / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D031307:Vicia faba / Q000737:chemistry
D008372:Manure; D012987:Soil; D010758:Phosphorus; D009584:Nitrogen