刈割强度对开花期醉马草繁殖特性的影响

Effects of Cutting Intensity and Flowering Period onReproductive Characteristics of Achnatherum inebrians

为了研究不同刈割强度下醉马草(Achnatherum inebrians)生长特征和生物量变化,探明不同刈割强度对醉马草繁殖特征的抑制作用,本试验以生长在荒漠、草原、草甸生境下的醉马草为对象,在醉马草开花期进行刈割,结实期取样进行测定,基于植株株丛横截面半分比的划分,设置0%(CK)、25%、50%、75%、100%5个刈割强度,测定形态特征、结实特性以及生物量等指标,选出较优和有针对性的刈割强度。研究结果表明,在5种刈割强度下,各生境中与CK对比,25%~100%刈割强度对醉马草生殖枝数量、千粒重和结实率均具有显著抑制作用;100%刈割强度抑制各生境的总生物量、营养枝和生殖枝生物量(P<0.05)。草原生境多为等补偿或欠补偿,而荒漠和草甸生境多为欠补偿,补偿指数总体随着刈割强度的增加而降低,重度刈割均会使醉马草出现显著的欠补偿生长。醉马草开花期高强度刈割能够控制醉马草有性生殖,实现有效防控。

In order to study the growth characteristics and biomass changes of Achnatherum inebrians under different cutting intensities in the hope of ascertaining the inhibitory effects of different cutting intensities on the reproductive characteristics of Achnatherum inebrians.This experiment focuses on Achnatherum inebrians growing in desert,steppe,and meadow habitats.During the flowering period of Achnatherum inebrians,samples were taken and measured during the fruiting period.Based on the division of the plant bundle cross-section half ratio,0%(CK),25%,50%,75%,75%and 100%were set to measure morphological characteristics,fruiting setting characteristics,biomass and other indicators,thus selecting the better and targeted cutting intensity.The research results indicated that under 5 different cutting intensities,compared with CK in various habitats,25%to 100%cutting intensities had a significant inhibitory effect on the number of reproductive branches,thousand grain weight,and seed setting rate of the Achnatherum inebrians;100%cutting inhibited the total biomass,nutrient branch biomass,and reproductive branch biomass of each habitat(P<0.05).In addition,steppe habitats were mostly equal compensated or undercompensated,while desert and steppe habitats were mostly undercompensated.The compensation index generally decreased with the increase of cutting intensity,and heavy cutting would cause significant undercompensated growth of the drunken horse grass.In short,high cutting during the flowering period of the Achnatherum inebrians can control its sexual reproduction and ultimately achieve effective prevention and control.