Asymmetric effects of planting pattern and density on leaf-height traits of Glycine max and Amaranthus retroflexus  

种植方式与密度对大豆和反枝苋叶片、株高性状的不对称影响

作　　者：Ping Lu Yan Pang Huai-Jing Wang Zi-Han Zhang Xin Dai Xue-Wei Bing Qiu-Yu Yuan 

机构地区：[1]School of Resources and Environment,Northeast Agricultural University,Harbin 150030,China

出　　处：《Journal of Plant Ecology》2024年第6期345-362,共18页植物生态学报(英文版)

基　　金：funded by the National Natural Science Foundation of China(32172431,31770582);the Natural Science Foundation of Heilongjiang Province(LH2023C001).

摘　　要：Environmentally sustainable weed management is crucial to meet the increasing demand for food.Previous studies have demonstrated that improving spatial uniformity and planting density can effectively suppress weeds.However,research on how planting patterns(PPs)affect the functional traits of crops and weeds is limited.In 2019 and 2021,we conducted a field experiment to compare the functional traits and biomass of Glycine max and Amaranthus retroflexus in two PPs-row(R)and equidistant(E)-with varying combinations of G.max and A.retroflexus densities.We found that the equidistant planting pattern(EPP)amplified the competitive ability of G.max in size-asymmetric competition with A.retroflexus,and this advantage increased alongside higher G.max density,primarily due to functional traits related to light acquisition.In the EPP,G.max established a closed canopy during the early growth stage,reducing light availability to A.retroflexus.This advantage was reflected in higher leaf area index(LAI)and leaf dry weight for G.max in the EPP than in the row planting pattern(R_(P)P),while A.retroflexus experienced reduced LAI and plant height due to increased shading in the EPP.Consequently,the EPP enhanced the total biomass and yield of G.max by an average of 40.8%and 37.7%,respectively,while the biomass of A.retroflexus decreased by an average of 34.5%compared with the R_(P)P.These results suggest that adopting an EPP with a high density of G.max,could be an effective strategy for suppressing A.retroflexus and improving crop yield.探索可持续的杂草管理对满足日益增长的粮食需求至关重要。已有研究表明,采用高密度均匀种植可有效抑制杂草生长。然而,针对这种种植方式如何影响作物和杂草功能性状的研究仍较少。2019和2021年,本研究通过田间试验方法比较了在不同大豆(Glycine max)种植方式(常规行种/均匀种植)和其与反枝苋(Amaranthus retroflexus)不同密度组合条件下两个物种的功能性状和生物量。结果发现,高密度均匀种植增强了大豆对反枝苋的竞争力,其放大了大豆相对于反枝苋在生长初期由于其植株较大的不对称竞争优势。这种竞争优势主要与光获取相关的功能性状有关,在均匀种植方式下,大豆在生长初期形成了封闭的冠层,减少了反枝苋获得的光资源。相较于常规行种,均匀种植增加了大豆叶面积指数和叶干重,降低了反枝苋叶面积指数和株高。因此,相较于常规行种,均匀种植下大豆的总生物量和产量分别平均提高了40.8%和37.7%,而反枝苋生物量则平均减少了34.5%。上述结果表明,采用高密度均匀种植是大豆田抑制反枝苋,并提高大豆产量的有效策略。

关 键 词：planting pattern functional traits crop-weed competition Glycine max Amaranthus retrofexus 

分 类 号：S51[农业科学—作物学]