梨远缘花粉原位萌发及生长特性

应用荧光标记方法对梨远缘花粉在‘丰水’和‘噢嗄二十世纪’柱头上萌发及花粉管生长特性进行观察,结果表明:(1)梨远缘花粉均能在柱头上萌发,但其萌发率不同,授粉后24 h,在‘丰水’柱头上‘红叶桃’花粉萌发率最高,达62.8%,而‘盖县大李’花粉萌发率仅为12.0%,各种远缘花粉在‘丰水’柱头萌发率均高于‘噢嗄二十世纪’柱头。(2)各种远缘花粉管在梨柱头或花柱内生长情况也有差异,‘红叶桃’等核果类花粉管在梨柱头上均表现为扭曲、盘绕等现象,不能穿过柱头;‘红星’和‘红富士’花粉管虽然有少量穿过柱头,但不能进一步在花柱内生长,表现为扭曲变形、先端膨大等不亲和性现象。因此,梨与远缘果树杂交不亲和在柱头上就已发生,这与梨自交不亲和反应发生在花柱内的现象不同。

In Situ Germination and Pollen Tube Growth of Distant Pollens in Pear

The germination and pollen tube growth of pear distant pollens on the stigma in 'Housui' and 'Osa-nijisseiki' were observed by fluorescence microscopy,which showed that(1) pear distant pollens could germinate on the stigmas but the germination rates differed;24 hours after pollination,the germination rate of the pollens of 'Hongyetao'(a peach variety) on the stigmas of 'Housui' peaked reaching(62.8)% and the germination rate of the pollens of 'Gaixiandali'(a pear variety) on the stigmas of 'Housui' was only 12.0%;The germination rates of various pollens on the stigmas of 'Housui' were higher that those of 'Osa-nijisseiki';(2) The pollen tubes of different distant pollens grew different on the stigmas or inside the styles,the pollen tubes of such drupe trees as 'Hongyetao' appearing twisty and coiled not capable of penetrating the stigmas and a few pollen tubes of 'Hongxing' and 'Red Fuji'(apple variety) could penetrate the stigmas but could not grow inside the styles showing such incompatible symptoms as twisting and swelling at their tips.Therefore,the incompatible reaction occurred on the stigmas in the distant hybridization between pear and its distant fruit trees and this was different from the conclusion that the self-incompatible reaction of pear occurs inside the styles.