种内竞争对稗草生物量生殖分配的影响

生殖分配控制着植物的终生生殖与生存的平衡,为此,通过不同密度处理探讨种内竞争对稗草生物量生殖分配的影响.设置5个密度处理:M1,1.17×105株/hm2(1株/盆)；M2,3.52×105株/hm2(3株/盆)；M3,7.04×105株/hm2(6株/盆)；M4,10.56×105株/hm2(9株/盆)；M5,14....

Effects of Intra-specific Competition on Biomass Allocation of Echinochloa crusglli

Reproductive allocation controls the reproduction and survival balance of plants.Effects of intra-specific competition on the biomass allocation of Echinochloa crusglli(L.) beauv under different densities were studied in this experiment.Five density treatments were designed: M1,1.17×105 plants/ha(1plant/pot);M2,3.52×105 plants/ha(3plants/pot);M3,7.04×105 plants/ha(6plants/pot);M4,10.56×105 plants/ha(9plants/pot);M5,14.08×105 plants/ha(12plants/pot).The biomass and biomass allocation pattern of its various organs were determined and analyzed at flowering and grain filling periods.The results showed that the total biomass was basically unchanged after flowering under all treatments,in which the biomass of vegetative organs was decreased but that of the reproductive organ was increased.At either flowering or grain filling period,within populations there was a certain mechanism to alleviate intra-specific competition which reduced the weight per plant,weight per tiller and biomass of various organs with the increase of density.In the absence of intra-specific competition under low-density treatment(M1),biomass allocation was mainly to increase the distribution of roots,and to reduce the distribution of stems.In the presence of competition,the difference of biomass distribution between plant organs was not significant at the flowering period.At the grain filling period,with increase of intra-specific competition,E.crusglli unit area by the light decreased,resulting in the increase of leaf allocation and decrease of stem allocation,but the allocation of reproductive organs reached the maximum of 17.34% and 17.28% under the medium-density of M2 and M3 treatments.