种间相互作用对牧草间作体系生产力的影响

摘要

To uncover effects of interspecific interactions on productivity of the intercropping system of intercropping Stylosanthes guianensis / Paspalum atratum,three treatments,respective monoculture of S.guianensis and P.atratum,P.atratum/S,guianensis reciprocal intercropping,were designed to observe difference in growth,biomass,and equivalent ratio of the biomass of the whole plant,phenology,as well as soil organic matter,total nitrogen and total phosphorus of sample plot under the three treatments in the whole growth period.The results showed the LER of biomass aboveground and underground was 3.05 and 3.52 respectively 270 days after planting in intereropping system and LER was greater than 1,which indicated that the intercropping system had its advantage.Compared with monoculture,phenology of P.atratum in intercropping system delayed for 5 days,and its growth and biomass were higher than those in monoculture.Its plant height,root length,dry yield and root yield were higher than those in monoculture by 9.67 cm,7.33 cm,345.50 g·stmin-1,131.67 g·stmin-1 respectively.Compared with monoculture,the stage of branch,flower buds and flowering of S.guianensis in intercropping system delayed for 5 days,15 days and 5 ～ 15 days respectively,and its growth and biomass were lower than those in monoculture.Its plant height,root length,root shoot ratio were lower than those in monoculture by 10.64 cm,0.54 cm,0.08,0.84 grain· strain-1,14.29 g·strain-1 and 1.48 g·strain-1.The increase in organic matter,total nitrogen and total phosphorus in the intercropping sample plot after planting was 0.039％ 0.003％ and 0.001％.The increase in organic matter and total nitrogen in monoculture of S.guianensis was 0.063％ and 0.006％ after planting.The total phosphorus decreased by 0.001％ after planting.Organic matter and total nitrogen decreased in monoculture of P.atratum by 0.017 ％ and 0.002％ after planting.It was concluded that S.guianensis used phosphobacteria for nitrogen fixation in BNF process.Phosphorus consumption led to the decrease in total phosphorus and increase in total nitrogen in monoculture of S.guianensis.%为了揭示种间相互作用对柱花草/黑籽雀稗间作体系生产力的影响,试验设计三个处理,分别是单作柱花草、单作黑籽雀稗、柱花草/黑籽雀稗间作,观测了三个不同种植模式作物整个生育的物候期、整个植株生长量、生物量、生物量的当量比及不同种植体系土壤有机质、全氮和全磷的差异.结果表明:①种植牧草270天后,间作体系地上部和地下部生物量的当量比分别是3.05和3.52,土地当量比大于1,表明柱花草/黑籽雀稗间种具有间作优势.②与单作相比,间作体系黑籽雀稗物候期推迟5天;其生长量、生物量均高于单作,株高、根长、干草产量和根系产量分别高于单作9.67 cm、7.33 cm、345.50 g·株-1、131.67 g·株-1.与柱花草单作对比,间作的分枝期、现蕾期、花期比单作分别推迟5天、15天、5～ 15天;其生长量和生物量低于单作,柱花草株高、根系深、根冠比、根瘤量、干草产量和根系产量分别低于单作10.64 cm、0.54 cm、0.08、0.84粒·株-1、14.29 g·株-1和1.48g·株-1;③间作体系土壤养分有机质、全氮、全磷比种植前增加的量分别为0.039％、0.003％、0.001％.单作柱花草样地有机质、全氮比种植前增加的量分别为0.063％、0.006％,磷比种植前减少0.001％;单作黑籽雀稗样地有机质、全氮比种植前减少0.017％、0.002％.表明,柱花草的间作提高了样地土壤有机质、全氮和全磷含量;柱花草在生物固氮过程中,以磷固氮,消耗磷素致使单作柱花草样地全磷量减少,全氮量增加.