除草剂(百草枯)对稗草生物量生殖分配及生长特性的影响

为了解稗草[Echinochloa crusglli(L.)Beauv.]在不同浓度除草剂条件下的资源分配特点,现选用百草枯为试验试剂,并据大田施用量设置5种施用浓度,分别测定不同浓度条件下稗草各器官生物量、生殖分株数量特征,并比较分析各器官生物量及生物量分配比例。试验结果表明:盛花期至结实期,稗草的总生物量基本保持不变,根、茎生物量及其分配比例逐渐减小:生殖器官的生物量及其分配比例逐渐增加;而叶生物量的变化无明显规律,生物量分配值随除草剂浓度的增加而增加。各生长时期内,器官生物量分配格局呈茎>根>叶>花(果)。生殖分株数量特征随除草剂浓度的增加而减小;在C1浓度条件下,稗草穗长、RAⅠ、RAⅡ呈最大值。

The Biomass Allocation of Echinochloa crusglli (L.) Beauv under Different Concentrations of Herbicide (Paraquat)

In order to understand the resource allocation characteristics under different concentrations of herbicides,paraquat was selected as the test reagent,and five application concentrations were set according to the application amount for rice fields to determine the biomass of every organs and the quantitative characteristics of reproductive plantlets of Echinochloa crusglli(L.) beauv under different concentrations,and to compare and analyse the biomass of each organ and biomass allocation ratios.The results indicated that from the flowering stage to the ripening stage,the total biomass of Echinochloa crusglli(L.) beauv kept basically unchanged,the biomass and biomass allocation ratio of root and stem decreased,the biomass and its allocation ratios of reproductive organs increased.There was no obvious law of change in the biomass of leaf,but the biomass allocation value increased with the concentration of herbicide.In each stage,the reproductive allocation ratios showed an order of stem>root>leaf>flower(seed).The quantitative characteristics of the reproductive decreased with the increase of the concentration of paraquat.Under the concentration of C1,the spike length,RAⅠ,RAⅡwere all the maximum.