关键词: 百日草（Zinnia elegans）, 花序浸染, 遗传转化, 真空处理, 花蕾时期

Abstract: Based on the observation of the head inflorescence morphology and ovary cytology of Zinnia elegans S5, the applicability of the transformation technology of Zinnia elegans was explored by using different ratios of Agrobacterium suspension, vacuum treatment method and non-tissue culture inflorescence infection method during the development of the head inflorescence. The results showed that the external morphology and cytological observation of S5 inflorescence development found that the carpels of small flower bud 7 and later development stages were in an open state. The bud 3 capitate inflorescence was treated with the Agrobacterium suspension of 1/2 MS + 0.03% Silwet L-77 + 10% sucrose + 0.01 mg/L 6-BA （OD_{600 nm}=0.4）, the obtaining 0.35% conversion rate. The vacuum intermittent treatment was beneficial to the improvement of the conversion rate. The better treatment combination was vacuum intermittent 2 min + 30 s treatment bud 5 to bud 7 capitulum. The conversion rate of small bud 7 to bud 9 could reach 3.23%~5.00%.

Key words: Zinnia elegans, inflorescence dipping, genetic transformation, vacuum treatment, bud period