化学溶液浸种对荆条种子萌发和幼苗抗旱性的效应

Effects of chemical solution soaking on seed germination and seedling drought resistance of Vitex negundo var. heterophylla

为筛选出既能提高荆条种子发芽率又能增强荆条幼苗抗旱性的化学溶液处理方式,研究了不同化学溶液浸种处理对荆条种子萌发及幼苗抗旱性的影响。结果表明:0.1%GA_3,0.2%H2O2和0.1%GA_3+0.5%CaCl_2混合溶液3种方式浸种24h均能够显著提高荆条种子的发芽势、发芽率和发芽指数。同干旱胁迫相比,0.1%GA_3+0.5%CaCl_2混合溶液浸种能够在最大程度上提高荆条幼苗的相对含水量和叶绿素含量,降低电解质渗透率和丙二醛含量,并进一步增加APX,CAT和POD的活性。混合溶液0.1%GA_3+0.5%CaCl_2浸种能够提高荆条种子的发芽率,同时有效提高荆条幼苗的抗旱性。

In order to find out the seed treatment methods for improving seed germination rate and drought resistance of Vitex negundo var.heterophyllaseedling,the seeds were soaked in GA3,H2O2,CaCl2,GA3＋CaCl2solutions with different concentrations for 24 h,and the germination potential,germination rate and germination index were measured and the physiological index of seedlings under drought stress for 21 d were assayed as well.The results showed that the germination potential,germination rate and germination index could be significantly enhanced by seed soaking in GA3,H2O2 and GA3＋CaCl2solutions with suitable concentration,and the treatments of 0.1% GA3,0.2% H2O2 and 0.1% GA3＋0.5% CaCl2 solutions were the best for seed germination.Soaking seed in 0.1% GA3,0.2% H2O2 and 0.1% GA3＋0.5% CaCl2 solutions alleviated the drought-induced damage through increasing relative water content and chlorophyll content as well as decreasing electrolyte leakage and MDA content in seedlings,and 0.1% GA3＋0.5% CaCl2 solution was the most effective.Besides,soaking seed in 0.1% GA3＋0.5% CaCl2 solutions enhanced the activities of APX,CAT and POD of seedlings.