芝麻花粉附着、萌发与花粉管伸长过程研究

Study of pollens adhesion,germination and pollen tube penitration of sesame

以中芝14号为试验材料,采用荧光显微镜和石蜡切片法研究芝麻花粉在柱头上附着、萌发、伸长及在花柱内生长全过程。于授粉后不同时间段连续取样固定,并进行显微观察和数据统计。结果表明,在芝麻柱头上,授粉后5min基本无花粉萌发,10min有极少量花粉萌发,30min大量花粉开始萌发,并长出花粉管。花粉管具明显的绿色荧光,进入羽毛状柱头后继续生长于花柱基部至子房顶部的引导组织内。授粉后2h,生长最快的花粉管已经到达花柱基部,花粉管的平均生长速度约为3.0mm/h。授粉后4h,大量花粉管进入子房。即使在授粉后24h,仍有部分花粉在萌发和生长中。

In this study,pollen adhesion,germination and pollen-tube penitration of sesame were characterized by paraffin sections and fluorescence microscope technique.A widely cultivated sesame variety,Zhongzhi No.14,was used as plant material.The results showed that there were no pollen grains adhered to the stigma 5min after pollination.Similarly,there were hardly any pollen grains adhered to the stigma 10min after pollination.However,large numbers of pollen grains began to germinate and the pollen tubes were growing out 30min after pollination.The pollen tube showed strong green fluorescence during germination and growing into transmitting tissue in style.Furthermore,the longest pollen tubes reached the bottom of style（the top of ovary） 2h after pollination.The average elongation rate of pollen tubes was estimated at 3.0mm per hour.At 4h after pollination,many pollen tubes had entered the ovary.Meanwhile,some pollen was still germinating or growing in pistil 24h after pollination.