PEG模拟干旱胁迫对加拿大飞蓬种子萌发及幼根生长的影响  

Effects of PEG simulated drought stress on Conyza canadensis seed germination and young root growth

作　　者：吴生海 王玉莹 杨春波[1] 李黎明 张一 杜凤国[1,2] WU Shenghai;WANG Yuying;YANG Chunbo;LI Liming;ZHANG Yi;DU Fengguo(College of Forestry,Beihua University,Jilin,Jilin 132013,China;Key Laboratory of State Forestry Administration on Conservation and Efficient Utilization of Precious and Rare Forest Resources in Changbai Mountain,Jilin,Jilin 132013,China)

机构地区：[1]北华大学林学院,吉林吉林132013 [2]长白山特色森林资源保育与高效利用国家林业局重点实验室,吉林吉林132013

出　　处：《生物安全学报（中英文）》2024年第1期32-37,共6页Journal of biosafety

基　　金：国家林业和草原局林业外来物种调查与研究专项(KJZXSA202019)。

摘　　要：【目的】研究干旱胁迫对加拿大飞蓬种子萌发及幼根生长的影响,为科学防控加拿大飞蓬入侵提供依据。【方法】以当年生加拿大飞蓬成熟种子为材料,分别用蒸馏水(CK)和不同浓度5%、10%、15%、20%、25%的聚乙二醇溶液(PEG)(分别表示轻度、中度、重度、极度和极重度干旱胁迫强度)对加拿大飞蓬种子进行处理。测定日相对发芽率、发芽率、发芽势等指标,分析加拿大飞蓬种子萌发情况;测定幼苗根系宽、根系高、根平均直径、根面积、总根尖数及根分叉数,分析其幼苗根生长情况;并测定种子恢复萌发情况。【结果】无干旱胁迫的加拿大飞蓬种子萌发指标最高,随着干旱胁迫强度增加,种子萌发指标减小,极重度干旱胁迫下加拿大飞蓬种子不萌发。与CK相比,轻度干旱胁迫和重度干旱胁迫对加拿大飞蓬根平均直径影响不显著,但会促进侧根与不定根生长;重度干旱胁迫下,加拿大飞蓬的总根尖数和分叉数显著增加。加拿大飞蓬种子在PEG浓度为20.13%的干旱胁迫下不发芽。种子在极度和极重度干旱胁迫下不萌发,但当水分条件充足时,种子依然具有萌发的能力。【结论】建议在加拿大飞蓬种子尚未成熟前进行人工拔除,或在加拿大飞蓬入侵地种植耐旱强、生长快、根系发达、竞争性强的植物,以控制加拿大飞蓬的生长发育。【Aim】We investigated the effect of drought stress on Conyza canadensis seed germination and radicle growth,aiming to provide a scientific basis for the prevention and control of C.canadensis invasion.【Method】Mature C.canadensis seeds from the current year were treated with distilled water and polyethylene glycol(PEG)solutions of different mass fractions(5%,10%,15%,20%,and 25%).These mass fractions represented mild,moderate,severe,extreme,and extremely severe drought stress intensities,respectively.We measured various indices,including daily relative germination rate,germination rate,and germination potential,to analyze the seed germination potential of C.canadensis.Additionally,we measured seedling root width,root length,average root diameter,root area,total number of root tips,and root branching number to assess radicle growth capacity.Seed recovery germination was also measured.【Result】Germination indicators were highest for C.canadensis seeds not exposed to drought stress.As drought stress intensity increased,seed germination indicators decreased,and C.canadensis seeds did not germinate under extremely severe drought stress.Compared with control seeds,mild drought stress and severe drought stress had no significant effect on the average root diameter of C.canadensis but did promote the growth of lateral and indefinite roots.These studies summarize the impact of PEG induced drought stress on the germination and radicle growth of C.canadensis seeds.C.canadensis seeds do not germinate under drought stress with a PEG mass fraction of 20.13%.Seeds do not germinate under extreme and severe drought stress,but when water conditions become sufficient,seeds regain the ability to germinate.【Conclusion】These results suggest manual removal of plants before C.canadensis seeds have matured or the planting of drought-resistant,fast-growing,well-rooted,and highly competitive plants in C.canadensis invasion areas to control the growth and development of C.canadensis.

关 键 词：加拿大飞蓬 干旱胁迫 种子萌发 幼根生长 PEG溶液 

分 类 号：S451[农业科学—植物保护]