胜红蓟种子在不同土壤环境的存活力OA北大核心CSTPCD

[Objectives]The paper aimed to explore the viability of Ageratum conyzoides seeds in different soil environments to reveal the reasons why A.conyzoides seeds form dominant population in farmland.[Methods]This study was conducted to examine the seed viability and dynamic of A.conyzoides stored for 210 d after harvesting after storage at different temperature,humidity,depth,pH value,salt concentration and osmotic potential in soils.[Results]In the soil environment of 10-30℃,the optimum germination temperature was always 20 ℃.Therefore,the germination rate of seeds of A.conyzoides at 20 ℃ after the breaking of dormancy was used as a proxy for seed viability.The viability of seeds stored at 5-30 ℃ and soil humidity 20％for 120 d was higher than 90％under different soil temperature and humidity conditions.Seed viability did not decrease significantly after 180 d of storage at 20 cm of soil depth;it only decreased to 60％stored at 30 cm of soil depth.The viability of the seeds of A.conyzoides stored for 120 d at pH 4-10 was maintained above 95％with no significant differences among treatments.The seed viability of A.conyzoides stored for 150 d in different NaCl concentrations in the soil environment was unchanged more than 95％;after 180 d of storage,the viability of seeds treated with 160 mmol·L-1was significantly lower than that of the other treatments.Seed viability was maintained above 95％in all treatments when it was stored for 150 d in a soil environment with an osmotic potential above-0.8 MPa;it only decreased to 85％when it was stored for 180 d with an osmotic potential below-1 MPa.[Conclusions]It could be inferred that the seed viability of A.conyzoides showed strong adaptability and tolerance to fluctuations in soil temperature and humidity,pH value,salt concentration,osmotic potential,and burial depth in 210 d,which might be the reason for its becoming a destructive weed in agricultural fields in tropical subtropical regions.