Studies on Embryo Induction from Un-pollinated Ovary Culture and Regenerated Plant in Cucumber
LIU Li-gong1, WANG Jing2, ZHAO Hong1, YANG Hong-hong1, ZHANG Feng1*
(1Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(North China),Vegetable Research Center of Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China; 2Beijing Vocational College of Agriculture,Beijing 102442,China)
Abstract:Un-pollinated ovary culture was applied in 7 different cucumber(Cucumis sativus L.) varieties.The embryo yield was significantly different among different genotypes.Among them, the highest embryo formation rate was ‘Beijing 102’, reaching 25.3%, the lowest embryo formation rate was 'Erhuang No.3’, reaching 0.7%.Taking ‘Beijing 102’,'Zhongnong No.26’ and ‘Jinyou No.1’ as experimental material,further studies were conducted about the effects of thermal treatment,exogenous hormones and different growth stage of plant on embryo induction yield.The results showed that a thermal shock at 35 ℃ for 2 days could gain the highest embryo yield,and the differential medium with 0.20 mg·L-1 NAA and 0.8 mg·L-1 6-BA was optimal for embryo differentiation.The highest embryo yield was harvested with ovary selected at 21-30 nodes of the plant stem.When the GA concentration in regeneration medium reached 0.4-0.8 mg·L-1,the ‘blunt with blossom’ phenomenon of regenerated plant could be effectively vanished.Thus,the plant regeneration rate was increased.The ratio of diploid plants in regenerated plants was 70%,and the DH plant ratio in diploid plants was 84%.