Allelopathic effects of decomposed leaf litter from intercropped trees on rape

Authors : XIAOXI ZHANG, ZENGWEN LIU, NAN TIAN, NHU TRUNG LUC, BOCHAO ZHU, YUANHAO BING

Pages : 898-908

View : 15 | Download : 8

Publication Date : 2015-12-01

Article Type : Research Paper

Abstract :Abstract: The allelopathic effect of decomposed litter from trees interplanted with crops is a key problem in the intercrop agroforestry business that could influence the economic benefits and sustainable development of ecoagriculture. In our study, the litter from 12 common intercropped tree species was collected from the Guanzhong Plain insert ignore into journalissuearticles values(Shaanxi Province, China); and mixed with soil, incubated to allow decomposition for 120 days, and then extracted using water. The water extracts at different concentrations were used for fi??lter paper-dish cultivation of rape insert ignore into journalissuearticles values(Brassica napus); seeds. Indicators of the germination and growth of seedlings were measured to investigate the allelopathic effects of decomposed litter on rape. The results showed that in rape the most sensitive indicators of harmful allelochemicals derived from decomposed litter were the germination speed index and catalase activity of seedlings. Moreover, extracts of decomposed medium insert ignore into journalissuearticles values(soil); containing litter from Paulownia fortunei, Acer truncatum, Zanthoxylum bungeanum, Juglans regia, Diospyros kaki, Prunus persica, Prunus armeniaca, and Ziziphus jujube were beneficial to the germination and seedling growth of rape at all concentrations examined, and thus these trees could be safely interplanted with rape. Extracts from Eucommia ulmoides, Populus canadensis, and Malus pumila inhibited the germination and seedling growth of rape, and thus the use of these trees in intercropping should be reduced. Extracts from Pyrus bretschneideri showed growth promotion at lower concentrations insert ignore into journalissuearticles values(10 and 20 mg mL-1); but were growth inhibitive at a high concentration insert ignore into journalissuearticles values(40 mg mL-1);; thus, it could be intercropped with rape but at a low density.
Keywords : Allelopathy, decomposition, germination status, leaf litter, rape, water extraction