苗期低温胁迫对当归生长及生理特性的影响OA

Objective To study the effects of low temperature stress during seedling stage on growth and physiological characteristics of facility-cultivated Angelica sinensis(Oliv.)Diels seedlings.Methods 120-day-old Angelica sinensis seedlings from off-season facility cultivation were used as experimental materials.The seedlings were subjected to artificial low temperature stress at 5℃,10℃,and 15℃for 1 to 7 days,followed by a 7-day recovery treatment.Growth and physiological indicators were measured.Results After low temperature stress,the facility off-season Angelica sinensis seedlings showed decrease in plant height,stem diameter,root length,root diameter,leaf area,shoot and root fresh weight,and shoot and root dry weight,with a more pronounced effect on aboveground parts.Chlorophyll content was decreased significantly(P<0.05).Malondialdehyde(MDA)content was increased.The activities of SOD and POD were generally increased.The contents of Pro,soluble protein,and soluble sugar were increased,and all showed recovery after 7 days of recovery treatment.Principal component analysis(PCA)revealed that the contents of Pro,soluble protein,and soluble sugar were significantly negatively correlated with the growth indicators of Angelica sinensis seedlings,while CAT activity was significantly positively correlated with the growth indicators.Conclusion Angelica sinensis seedlings under low temperature stress alleviated the damage by slowing down growth and increasing the activities of antioxidant enzymes and the contents of osmoregulatory substances.