低温预处理对小麦花药内源激素的影响

以烟农19和皖麦41为材料,应用酶联免疫吸附法(ELISA)测定不同时间低温预处理的小麦花药内源激素ABA、GA₃、JA、IAA含量,并统计了低温预处理后小麦花药愈伤组织诱导率和胚性愈伤组织比例,分析了低温预处理过程中小麦花药内源激素的变化规律及其对花药培养特性的影响。结果显示,小麦花药低温预处理2d愈伤组织诱导率最高,低温预处理6d胚性愈伤组织比例达到最大;低温预处理改变了花药内源激素ABA、GA、JA、IAA的含量,ABA、GA、JA含量随预处理时间的延长呈较大的波动变化;低温预处理6d时ABA,JA含量达最大值,GA呈波动下降趋势,IAA含量在低温预处理2d达到最高值,其后逐渐下降;IAA、IAA/ABA、IAA/JA变化与花药愈伤组织诱导率表现出很强的正相关,ABA、JA与胚性愈伤组织比例表现出很强的正相关,GA/ABA与胚性愈伤组织比例表现出负相关。表明低温预处理改变了小麦花药内源激素的含量和比例,阻断了花粉原来的发育方向,使其由配子体的发育途径转向孢子体的发育途径,从而影响了小麦花药培养诱导产生的愈伤组织的数量和质量。

EFFECT OF LOW TEMPERATURE PRETREATMENT ON THE VARIATION OF ENDOGENOUS HORMONES IN WHEAT ANTHER

The effect of low temperature pretreatment on the content of endogenous hormones (ABA, GA, JA and IAA) of wheat anther was studied to explore the role of endogenous hormones in the dedifferentiation of wheat anther. With two wheat varieties, Yannong 19 and Wanmai 41 as materials, enzyme-linked immuno sorbent assay (ELISA) method was used to determine the content of GA3, IAA, ABA and JA of wheat anther treated by low temperature at different time. Combining the influence of low temperature pretreatment on the frequency of callus induction and the ratio of embryogenic calli, the change law of endogenous hormones and the effect of low temperature pretreatment on the culture characteristics of wheat anther were analyzed by relative statistic software. The results showed that after treated with low temperature for 2 days, the wheat anther had the highest frequency of callus induction ratio while the ratio of embryogenic calli reached the maximum after treated with low temperature for 6 days. The content of endogenous ABA, GA, JA and IAA in wheat anther varied with the low-temperature pretreatment,and with the prolongation of pretreatment duration, the content of ABA, GA, JA had larger fluctuation. Treated for 6 days, the content of ABA and JA reached the maximum. The content of GA exhibited fluctuating and descending tendency, and IAA reached the maximum after 2 days and decreasing gradually afterward. The correlation analysis indicated that IAA, IAA/ABA, IAA/JA positively correlated with the frequency of callus induction, and ABA and JA positively correlated with the ratio of embryogenic calli. There was a significantly negative correlation between the GA/ABA and the ratio of embryogenic calli. Low temperature pretreatment changed the content of endogenous hormones and their ratio in the anthers, thus interrupted previous developmental direction of pollen and induced microspores development from gametophytic way to sporophytic way, which influenced the quality and quantity of calli.