蝴蝶兰组织培养过程中减轻外殖体褐化的方法研究

Method Research of Alleviating Explant Browning in Phalaenopsis Tissue Culture

采用表面活性剂（Tweens20）20×10^-6处理10min、70％酒精浸泡30s、0．5％的次氯酸钠溶液浸泡5min的方法消毒外殖体最佳；采用带腋芽的、抽4节的花梗为外殖体诱导率最高为90．2％，褐化系数最低9．8％；培养基中添加10mg／LAA和1000mg／LPVP抗褐化效果较好；添加了2000mg／L或1000mg／LAC的培养基褐变比对照轻；在诱导阶段蔗糖采用低浓度诱导效果较好；先采用低温（17～20℃）处理3～5d，然后转到正常温度培养，可以减轻褐化程度；增加光照强度外殖体褐变严重，黑暗培养的外殖体褐变发生推迟而且程度轻；蝴蝶兰在pH5．6时，褐化较轻。

Treating the explant with tweens （20 × 10^-6） in 10 rninute, then putting the explant in 70% alcohol with 30 second, and then immersing the explant in 0.5% sodium hypochlorite with 5 minute was the best method. Used footstalk with axillary bud and four steps as explant, then we got the highest inducing ratio to 90.2 % and the lowest browning modulus to 9.8 %. Appending AA with 10mg/L and PVP with 1000mg/L to the substrate could get the best effect of browning resistance. The browning of substrate with AC （2000mg/L or 1000mg//L） is lower than the contrast. We got a better inducing effect with a lower sugar intensity. Dealing the explant with a low temperature （17-20℃） in 3-5 days, and then returning to the normal temperature could alleviate the browning. Enhancing illumination intensity could aggravate browning, and culturing in dark could reserve and alleviate browning. We got a lower browning with pHS. 6 in Phalaenopsis.