节节麦密度对小麦生长发育与竞争能力的影响

Effects of Aegilops tauschii Density on Growing Development and Competitive Capacity of Wheat

【目的】探明入侵物种节节麦不同密度对小麦生长发育及竞争能力的影响,为冬小麦田节节麦的科学防控提供参考。【方法】采用密度添加系列试验方法,固定目标物种小麦的密度为300株/m^(2)条件下,分析入侵物种节节麦密度25~200株/m^(2)不同处理条件下小麦形态及生物量的变化特征。【结果】随节节麦密度增加,小麦生长指标下降,节节麦密度达200株/m^(2)时,小麦株高、叶面积和总生物量分别较对照(小麦单种)下降42.60%、42.05%和42.97%,降幅显著(P<0.05)。随节节麦密度增加,小麦根冠比(R/C)逐渐下降,比叶面积(SLA)不断升高,节节麦密度为200株/m^(2)时,小麦的R/C较对照降低12.00%,SLA增加24.52%,但变化不显著。节节麦密度为25株/m^(2)时,小麦的竞争平衡指数(CB)大于0;节节麦密度为50~200株/m^(2)时,小麦的竞争平衡指数小于0。【结论】节节麦对小麦的竞争危害与其密度呈正相关,节节麦密度为25株/m^(2)时,其竞争能力小于小麦,对小麦竞争抑制相对较弱;节节麦密度达50株/m^(2)及以上时对小麦生长发育造成严重影响。

【Objective】The effects of different Aegilops tauschii density on growing development and competitive capacity of wheat are discussed to provide a reference for scientific prevention and control of A.tauschii in winter wheat field.【Method】The effect of 7 A.tauschii densities(0/m^(2),25/m^(2),50/m^(2),75/m^(2),100/m^(2),150/m^(2) and 200/m^(2)) on variation characteristics of wheat morphology and biomass is analysed when the wheat density is 300 plants/m^(2).【Result】The growth index of wheat declines with increase of A.tauschii density when the A.tauschii density is up to 200 plants/m^(2),the height,leaf area and total biomass of wheat decrease by 42.60%,42.05% and 42.97% compared with CK respectively(P<0.05).With increase of A.tauschii density,the root/crown ratio(R/C) decreases gradually but specific leaf area(SLA) rises continuously.When the A.tauschii density is 200 plants/m^(2),the R/C decreases by 12.00% and SLA increases by 24.52% compared with CK.When the A.tauschii density is 25 plants/m^(2),the competitive balance index(CB) of wheat is more than 0.When the A.tauschii density is 50~200 plants/m^(2),the competitive balance index(CB) of wheat is less than 0.【Conclusion】The competitive damage of A.tauschii is positively related to its density.When the A.tauschii density is 25 plants/m^(2),the competitive capacity is less than wheat.When the A.tauschii density is ≥50 plants/m^(2),A.tauschii has a strong impact on growing development of wheat.