乐东拟单性木兰茎段愈伤组织诱导与褐变控制的研究  

A Study on Techniques of Inducing Callus and Controlling Browning of Stem Segments of Parakmeria lotongensis

作　　者：苏梦云[1] 姜景民[1] 

机构地区：[1]中国林业科学研究院亚热带林业研究所,浙江富阳311400

出　　处：《林业科学研究》2004年第6期757-762,共6页Forest Research

基　　金：科技部基础性工作专项子课题"亚热带珍贵经济树种资源收集;保存和利用"和亚热带林木培育实验室基金课题"难繁阔叶树种组织培养技术的研究"

摘　　要：利用乐东拟单性木兰成龄树嫩枝茎段作外植体,研究了控制褐变和组织培养的技术。试验结果表明,抗氧化剂控制褐变的效果比吸附剂好,以抗坏血酸最好,其次是巯乙醇和二硫苏糖醇。在培养基中分别加入抗坏血酸(10mgL-1)、巯茎乙醇(1mL·L-1)和二硫苏糖醇(1 5mg·L-1)使外植体的褐变率分别比对照降低67%、53%和33%。在接种前,将外植体在4℃下冷处理2h,能使外植体的褐变率从对照的35%降低为25%。1 2MS和WPM均是较合适的基本培养基。外植体在BA1 5mg·L-1+NAA0 2mg·L-1+2,4 D1 0mg·L-1的激素组合下,能诱导出较多的愈伤组织;在WPM+BA1 5mg·L-1+KT0 5mg·L-1+NAA0 2mg·L-1+2,4 D0 2mg·L-1的培养基上,能产生较多的不定芽和愈伤组织;WPM+BA1 5mg·L-1+KT0 5mg·L-1+NAA0 2mg·L-1+IAA1mg·L-1的培养基适合于芽增殖;在1 2MS+NAA0 3mg·L-1+IBA0 2mg·L-1的培养基上,添加15g·L-1活性炭有利于生根。Techniques of controlling browning and tissue culture on stem segments of young branches on mature trees of Parakmeria lotongesis were researched.Results obtained showed that 1/2 MS medium and WPM medium were more suitable to tissue culture of Parakmeria lotongensis.A lot of callus were induced on WPM medium containing BA 1.5 mg·L^(-1),NAA 0.2 mg·L^(-1) and 2,4-D 1.0 mg·L^(-1).A large number of adventitious buds and some calluses induced from calluses were observed on WPM medium supplemented with BA 1.5 mg·L^(-1),KT 0.5 mg·L^(-1),NAA 0.2 mg·L^(-1) and 2,4-D 0.3 mg·L^(-1).The medium of WPM+BA 1.5 mg·L^(-1)+KT 0.5 mg·L^(-1)+NAA 0.2 mg·L^(-1)+IAA 1.0 mg·L^(-1) was fit to shoot proliferation. Plantlets rooted well on 1/2 MS medium containing NAA 0.3 mg·L^(-1) and IBA 0.2 mg·L^(-1) with 1.5 percent active charcoal. The effects of antioxidizer on controlling oxidative browning was better than that of adsorbent.There were difference among various antioxidizers on controlling browning.Their capacities of preventing browning were as follows:ascorbic acid (vitamin C)>mecapto ethanol>dithiothreitol.Effects of polyvinylpyrrolidone (PVP) and active charcoal on preventing browning were not obvious. Oxidative browning rates of explants on WPM medium supplemented with ascorbic acid (10 mg·L^(-1)),mecapto ethanol (1 mL·L^(-1)) and dithiothreitol (0.5 mg·L^(-1)) were 67%,53% and 33% lower than that of without any antioxidizer in initial culture and subculture.The treatment that explants were putfor 2 h at 4 ℃ before inoculation favor the decreasing browning, esplants browning rate decreased from 35% (CK) to 25%.

关 键 词：乐东拟单性木兰 茎段 愈伤组织 褐变现象 控制措施 组织培养 

分 类 号：S685.99[农业科学—观赏园艺]