摘要
【目的】探究豫西浅山丘陵区不同经营世代刺槐和不同质量浓度根际土浸提液对刺槐种子萌发和幼苗生长发育过程的影响,揭示刺槐多代经营培养下根系分泌物对刺槐更新的化感效应,为刺槐破解连栽障碍和实现可持续经营提供理论依据。【方法】选取刺槐不同经营世代林(一代、二代、三代林)为研究对象,以裸地为对照,各设置3块样地进行基本林分调查,分别制备1、5、10、50、100 mg/mL不同质量浓度刺槐根际土浸提液,进行刺槐种子萌发和幼苗生长试验,并测定种子萌发和幼苗生长等相应指标。【结果】刺槐根际土浸提液会对刺槐种子萌发产生一定影响,根据化感综合效应指数来看,在一代林中,随着根际土浸提液质量浓度的增加,对刺槐种子萌发的抑制作用逐渐增强;在二代、三代林中,仅在二代林5 mg/mL时表现出促进作用,其余质量浓度均表现为抑制作用;在三代林中,随着根际土浸提液质量浓度的增加,对刺槐种子萌发的抑制作用均表现为先减弱后增强的趋势。刺槐根际土浸提液会对刺槐幼苗生长产生一定影响,根据化感综合效应指数来看,在一代林与三代林中,均随着浸提液质量浓度的增加,对刺槐幼苗生长由抑制作用转为促进作用再转为抑制作用,一代林和三代林在100 mg/mL时均为抑制作用,且抑制作用最强;在二代林中,不同质量浓度刺槐根际土浸提液对刺槐幼苗生长均为促进作用;裸地中,随着浸提液质量浓度的增加,对刺槐幼苗生长的抑制作用先增强后减弱,在50 mg/mL时达到最大值。【结论】多代经营的刺槐林根系分泌物会在一定程度上抑制刺槐种子萌发,但对于种子萌发以后的幼苗生长阶段并不存在抑制作用,甚至有利于其生长。
[Objective]This paper explores the effects of different management generations of Robinia pseudoacacia and varied concentrations of rhizosphere soil extracts on the germination of R.pseudoacacia seeds and the growth and development of seedlings in the shallow mountains and hilly areas of western Henan Province of northern China,reveals the allelopathic effects of root exudates on R.pseudoacacia regeneration under multi generation management and cultivation so as to provide a theoretical basis for R.pseudoacacia to overcome continuous planting obstacles and achieve sustainable management.[Method]This study selected different generations of R.pseudoacacia forests(first generation,second generation,and third generation forests)as the research object,using bare land as the control,set up three sample plots for basic stand investigation,preparing 1,5,10,50,and 100 mg/mL of R.pseudoacacia rhizosphere soil extracts with different mass concentrations,conducting R.pseudoacacia seed germination and seedling growth experiments,and measuring corresponding indicators such as seed germination and seedling growth.[Result]The extract of R.pseudoacacia rhizosphere soil had a certain impact on the germination of R.pseudoacacia seeds.According to the allelopathic comprehensive effect index,in the first generation forest,the inhibitory effect on germination of R.pseudoacacia seeds gradually increased with the increase of concentration of rhizosphere soil extract in different management generations.In the second and third generation forests,only a promoting effect was observed at 5 mg/mL in the second generation forest.The remaining mass concentrations exhibited inhibitory effects.In the third generation forest,as the concentration of rhizosphere soil extract increased,the inhibitory effect on the germination of R.pseudoacacia seeds showed a trend of first weakening and then strengthening.The extract of R.pseudoacacia rhizosphere soil had a certain impact on the growth of seedlings of R.pseudoacacia.According to the comprehensive effect index of allelopathy,in both the first and third generations of forests,the growth of Robinia pseudoacacia seedlings changed from inhibitory effect to promoting effect and then to inhibitory effect with the increase of leaching solution concentration.Both the first and third generations of forests had inhibitory effect at 100 mg/mL,and the inhibitory effect was the strongest.In second-generation forests,different concentrations of Robinia pseudoacacia rhizosphere soil extracts had a promoting effect on the growth of Robinia pseudoacacia seedlings;In bare soil,as the concentration of extract increased,the inhibitory effect on the growth of Robinia pseudoacacia seedlings first increased and then decreased,reaching its maximum value at 50 mg/mL.[Conclusion]The root exudates of multiple generations of R.pseudoacacia forests will to some extent inhibit the germination of R.pseudoacacia seeds,but there is no inhibitory effect on the seedling growth stage after seed germination,and it may even be beneficial for its growth.
作者
张玉倩
彭祚登
Zhang Yuqian;Peng Zuodeng(School of Forestry,Key Laboratory for Silviculture and Conservation of Ministry of Education,Beijing Forestry University,Beijing 100083,China)
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2024年第7期77-89,共13页
Journal of Beijing Forestry University
基金
国家重点研发计划(2017YFD0600503)。
关键词
刺槐
根际土
种子萌发
幼苗生长
化感效应
Robinia pseudoacacia
rhizosphere soil
seed germination
seedling growth
allelopathic effect
