干旱胁迫下水杨酸和油菜素内酯对木薯苗生理特性的影响

采用盆栽试验．以木薯品种华南205（SC205）和华南8号（SC8）为试材．研究干旱胁迫下叶片分别喷施清水，40、60、100mg／L的水杨酸（SA），0．1、0．2、0．5mg／L的油菜素内酯（BR）对木薯苗生长和生理特性的影响。结果表明．干旱胁迫下木薯苗的电解质渗透率和丙二醛（MDA）含量升高．可溶性蛋白含量先升高后降低：复水后，木薯苗电解质渗透率和MDA基本恢复正常：与对照相比，干旱胁迫下喷施SA或BR能显著促进木薯苗的生长，显著降低细胞膜透性和质膜伤害程度，并显著提高可溶性蛋白含量：不同浓度处理中．以喷施100mg／LSA或0．2mg／LBR效果最好．

Effects of Salicylic Acid and Brassinolide on Physiological Characteristics in Cassava Seedling under Drought Stress

Using potted plant, cassava seedling were improved by foliage sprayed of water, 40, 60, 100 mg/L salicylic acid （SA）, 0.1, 0.2, 0.5 mg/L brassinolide （BR）, study the effects of SA and BR on growth and physiological characteristics of two cassava cultivars Huannan 205 （cv. SC205） and Huannan 8 （cv. SC8） under drought stress. The results showed that, under drought stress condition, increased leakage rate of electrolyte and content of MDA in leaves, soluble protein content raised firstly and then decreased; After rewater, cassava seedlings indicators （except the soluble protein） resumed to normal; Compared to control, SA and BR could significantly increase the growth of cassava seedlings, cell membrane permeability and membranic injury were significantly decreased, content of soluble proteins were significantly increased under drought stress; In different thickness disposals, SA sprayed at 100 mg/L and BR sprayed at 0.2 mg/L both could produce the best effects.