施肥对高粱生长、干物质积累与养分吸收分配的影响

以晋杂12号高粱(Sorghum bicolor(L.)Moench)为试验材料,采用"3414"试验设计研究了不同N,P,K施用量对高粱生长、干物质积累与养分吸收分配的影响。结果表明,在不施用N,P,K(基础地力)时,高粱根系和地上部生长及产量均较低,施用任意2种养分均会明显促进高粱生长;对N,P,K这3因素中任2因素设计最佳施用量时,施P肥具有较好的增产效果,施K肥没有增产效果。高粱干物质积累主要集中在拔节到抽穗期,成熟期干物质积累量达到最大,施肥高粱在不同生育时期干物质积累均高于对照,成熟期全株干物质积累量比对照增加19.77%。高粱干物质分配主要在茎叶部分,施肥对干物质分配比例没有显著影响。高粱N,P,K养分吸收量和分配比例最大的是K,其次是N,最低的是P。不同生育期高粱N,P,K养分吸收量和分配比例表现不同,N,P,K养分主要分配在茎叶上,穗部中养分分配比例大小为P>N>K。在施肥条件下,成熟期高粱N,P2O5,K2O养分吸收比例为1∶0.32∶2.22。施肥高粱在不同生育期对N,P,K的吸收比例与对照相似。

Effect of Fertilization on Growth, Dry Matter Accumulation, Nutrient Uptake and Distribution in Sorghum

Based on "3414" test,sorghum(Sorghum bicolor(L.) Moench) cv."Jinza 12" was used to investigate the effects of different combination application rates of N,P and K on growth,dry matter accumulation,nutrient uptake and distribution in different parts of plant under field experiment conditions.The experimental results showed as the following:When no N,P or K was applied,the root volume,plant growth and yield were the lowest among the 14 treatments,and application of any two of the three N,P or K,sorghum growth would be remarkably promoted;When any two of these three were designed as the optimum rates,P would significantly promoted grain yield whereas no such effect of K was observed;The dry matter mainly accumulated from shooting stage to heading stage,the maximum dry matter accumulation was obtained at the maturity stage.The dry matter accumulation at all stages of sorghum plants with fertilization was always higher than those without fertilization.The dry matter accumulation at maturity stage increased 19.77%,as compared with the control.The dry matter partitioning was mainly in the leaves and stems of the sorghum plants.Fertilization did not influence the proportion of dry matter partitioning.The order of the nutrient accumulations and the proportion of nutrient partitioning was K>N>P in sorghum plants.The nutrient accumulations and the proportion of nutrient partitioning were not the same at different stages.The nutrients of N,P and K were mainly partitioned in leaves and stems.The order of the proportion of nutrient partitioning was P>N>K in the grain sorghum head.The nutrient absorption ratio of N,P2O5 and K2O was 1∶0.32∶2.22 in whole plants with fertilizer supply at maturity stage.It showed similar trend in the nutrient absorption ratio of N,P2O5 and K2O in plants with and without fertilizer supply at different stages.