GA3诱导枇杷无核的组织解剖学观察

Anatomical study on the seedless formation of loquat (Eriobotrya japonica)treated by GA_3

为了阐明GA3处理枇杷导致无核的原因,以枇杷品种大五星为材料,采用石蜡切片法和花粉发芽试验等方法分别对花前经GA3处理枇杷花穗后的枇杷胚胎发育过程进行了研究。结果表明,1)枇杷的胚珠为倒生胚珠,双珠被,核型胚乳;2)花前用GA3处理枇杷导致无核的原因主要在于胚乳败育或者珠心退化导致胚退化,由于胚乳败育使胚发育所需要的营养不足,引起合子胚分裂异常,最终胚解体退化。但珠被在初期能够发育,所以形成败育种子(秕子)。

In order to clarify the seedless formation mechanism of the loquat cultivar Dawuxing （Eriobotryajaponica Lindl. ev. Dawuxing） treated with GA3 before flowering, the effects on the embryo development, pollen fertility and seedless were investigated by paraffin wax cut and pollen germination examination etc. The results showed that： （ 1 ） the fruit ovule was anatropous ovule with double layers integument and nuclear type endosperm; （2） the seedless mainly was caused by embryo abortion induced from endosperm and nucellus degeneration after treated with GA3; the endosperm degeneration caused the nutrition deficiency which made failure of embryo development, so the embryo abnormally divided and eventually degenerated. On the other hand, the integument could be developed at the early stage of the fruit development and sterile seed was formed.