《植物生理学报》 2015, 51(8): 1265-1272

环境胁迫对不同倍性大花蕙兰类原球茎增殖和分化的影响

周珊珊¹, 谢利¹, 王辰辉¹, 周玉亮¹, 曾瑞珍¹, 郭和蓉¹, 王木桂¹, 张志胜^1,2,*

¹华南农业大学广东省植物分子育种重点实验室, 广州510642; ²国家植物航天育种工程技术研究中心, 广州510642

通信作者：张志胜；E-mail: zszhang@scau.edu.cn；Tel: 13711026839

摘　要：

本文研究了低温、高温、紫外线和暗培养对二倍体、三倍体和四倍体大花蕙兰类原球茎(PLBs)增殖和分化的影响。结果表明, 10 ℃下培养, 四倍体PLBs增殖率最高; 35 ℃下培养20 d, 三倍体和四倍体PLBs死亡率显著低于二倍体, 表明多倍体PLBs具有更强的抵御低温和高温能力。紫外灯下培养30 d, PLBs的增殖率大小依次是四倍体＞三倍体＞二倍体, 与日光灯下相反, 说明多倍体PLBs对紫外线耐受力比二倍体强。暗培养30 d, 二倍体PLBs增殖率和芽分化率明显提高, 而三倍体和四倍体增殖率没有明显变化, 其芽分化率明显降低。在黑暗条件下继代培养30 d, 二倍体PLBs增殖率降低, 但降幅小于三倍体和四倍体, 芽分化率则进一步提高, 而三倍体和四倍体PLBs芽分化率进一步降低, 表明多倍体PLBs对黑暗的耐受力变弱。多倍体PLBs中SOD、POD和CAT的活性均高于二倍体, MDA含量低于二倍体, 抗氧化酶系及MDA的变化是导致多倍体PLBs抗性增强的重要原因。

关键词：大花蕙兰; 多倍体; 类原球茎; 环境胁迫

收稿：2015-01-29   修定：2015-06-20

资助：广东省科技攻关项目(2006A20201002和2011A020102004)和广州市农业局项目(1210699和1310998)。

Effects of Environmental Stress on Proliferation and Differentiation of Protocorm-Like Bodies of Different Ploidy Cymbidium hybridum

ZHOU Shan-Shan¹, XIE Li¹, WANG Chen-Hui¹, ZHOU Yu-Liang¹, ZENG Rui-Zhen¹, GUO He-Rong¹, WANG Mu-Gui¹, ZHANG Zhi-Sheng^1,2,*

¹Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agriculture University, Guangzhou 510642, China; ²National Engineering Research Center of Plant Space Breeding, Guangzhou 510642, China

Corresponding author: ZHANG Zhi-Sheng; E-mail: zszhang@scau.edu.cn; Tel: 13711026839

Abstract:

The proliferation and bud differentiation rate were measured in protocorm-like bodies (PLBs) of diploid, triploid and tetraploid Cymbidium hybridum with different conditions of low and high temperature, ultraviolet radiation (UV) and dark. The results showed that the proliferation rate of tetraploid PLBs was the highest at 10 ℃; and the death rates of triploid and tetraploid PLBs were significantly lower than that of diploid PLBs at 35 ℃ for 20 d, suggesting that polyploidy PLBs had a stronger ability to resist low and high temperature. Under UV light, the proliferation rates showed the following trend: tetraploid>triploid>diploid, but showed opposite trends under fluorescent lamp, indicating that polyploid PLBs were more resistant to UV light. After cultured in dark for 30 d, the proliferation and bud differentiation rates of diploid were obviously increased, however, the bud differentiation rates of polyploids were decreased, and their proliferation rates were little changed. Subcultured in dark for 30 d, the bud differentiation rate of diploid further increased, while those of polyploids further decreased, although the proliferation rate of diploid was decreased, but the range of decrease was lower than those of polyploids, demonstrating that polyploid PLBs were more sensitive to dark condition. The activities of SOD, POD and CAT in polyploid PLBs were higher than those in diploid, and MDA contents were lower than that in diploid, which indicated the changes of antioxidant enzyme system and MDA were important reasons for the enhancement of PLBs resistance.

Key words: Cymbidium hybridium; polyploid; PLBs; environmental stress