外源赤霉素和低温对赤芍种子萌发和幼苗耐低温能力的影响OA

To investigate the effects of exogenous gibberellin(GA3)and low temperature on the seed germination and low temperature resistance of Paeonia lactiflora seeds,this experiment used P.lactiflora seeds from 3 locations-Jilin(JL),Shandong(SD),and Henan(HN)as the experimental materials.The germination rate and germination time of the P.lactiflora seeds after soaking in water(CK)and with exogenous GA3(300 mmol/L)at room temperature and 4℃low temperature were determined.As well as the P.lactiflora seedlings that were frequently treated at room temperature and 4℃low temperature,soaked in water for seed germination and then germinated at room temperature.The contents of malondialdehyde(MDA),the activities of catalase(CAT)and peroxidase(POD)in the young rhubarb seedlings were measured under 3 treatments.water(CK),100 and 300 mmol/L GA₃.The results showed that,compared with CK,300 mmol/L exogenous GA3 could significantly increase the rooting rate of 3 production areas of P.lactiflora,shorten the germination time of embryonic roots and embryos,and also enhance the germination rate and germination potential.300 mmol/L exogenous GA3 could significantly enhance the CAT and POD activities of 3 production areas of P.lactiflora,and promote the accumulation of soluble sugars and soluble proteins;the CAT and POD activities of 3 production areas of P.lactiflora under low temperature all increased,as well as the contents of soluble sugars and soluble proteins.Among them,the antioxidant enzyme activity,soluble sugar and soluble protein accumulation of JL P.lactiflora were the highest;after low-temperature treatment,the MDA content of P.lactiflora from the 3 production areas all increased,and the MDA content of JL P.lactiflora showed the smallest increase.This indicated that JL P.lactiflora had a stronger ability to withstand low temperature,and 300 mmol/L exogenous GA3 could to some extent enhance the cold resistance of P.lactiflora.