青杨派树种雌蕊柱头可授性及最佳授粉时期

Stigma receptivity and the optimal pollination period of Populus spp. (Section Tacamahaca)

为提高青杨派树种有性杂交和多倍体诱导效率,以小青杨、小叶杨和哲引3号杨等青杨派树种及杂种为材料,用过氧化物酶试纸溶液测试结合授粉观察的方法对其雌蕊柱头可授性及最佳授粉时期进行了研究。结果表明：在温室水培条件下,青杨派树种花序可授期持续4~5 d;花序不同部位雌蕊柱头获得可授性的时间不同,基部雌蕊柱头最早获得可授性,而顶部雌蕊柱头获得可授性最晚;过氧化物酶试纸溶液在具有可授性的柱头表面呈现蓝色阳性反应,在育种实践中,可以应用过氧化物酶试纸溶液快速、有效地对青杨派树种雌蕊柱头可授性进行检测;3种青杨派树种雌花序柱头最佳授粉期为花序顶部露出芽鳞84~96 h,以此为参照点,对于适时施加理化处理诱导胚囊染色体加倍选育青杨三倍体等工作具有重要的指导价值。

The stigma receptivity and optimal pollination period were studied by testing with Peroxtesmo Ko solution and pollen germination on stigmas in Populus pseudo-simonii, P. simonii and P. pseudo-simonii x P. nigra var. lica, to increase the efficiency of hybridization and polyploid induction in Section Tacamahaca. The results showed that： 1 ） the stigma receptivity of Section Tacamahaca lasted 4-5 days under a greenhouse condition; 2） the pistils in different parts of catkin obtained the stigma receptivity at different time. The pistils at the base of catkin were the first to acquire stigma receptivity and those at the top acquired it last; 3） the stigmas with receptivity turned to blue by testing with Peroxtesmo Ko solution. In breeding procedure of Section Tacamahaca, the Peroxtesmo Ko solution can be applied to determine the stigma receptivity instantly and effectively; 4） the optimal pollination periods of three species of Section Tacamahaca were all in 84-96 hours after the catkins emerged from the bract scales. It is valuable to confirm the effective time of triploid induction through embryo sac chromosome doubling treated with chemical or physical techniques in Populus spp. （Section Tacamahaca）.