Light microscope study of pollen tube growth, fertilization and early embryo and endosperm development in the avocado varieties Fuerte and Hass.
Light microscope study of pollen tube growth, fertilization and early embryo and endosperm development in the avocado varieties Fuerte and Hass.
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鳄梨品种 Fuerte 和 Hass 花粉管生长、受精以及早期胚胎和胚乳发育的光学显微镜研究。
DOI：
10.1093/oxfordjournals.aob.a085739
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发表时间：
1979
期刊：
影响因子：
4.2
通讯作者：
M. Sedgley
中科院分区：
文献类型：
--
作者：
M. Sedgley
以油梨品种Fuerte和Hass为试材，在光学显微镜下观察了授粉后24 h内花粉管穿过胚珠的发育过程。到达子房后，花粉管沿着子房内壁表面生长。然后围绕珠柄生长，穿过珠被内珠孔和珠心顶端的乳头状细胞之间。它通过助细胞进入胚囊。授粉后48 h，胚囊中出现精核，极核和精核的融合发生在卵和精核融合之前。胚乳核最先分裂，随后细胞壁形成。受精卵的第一次分裂发生在授粉后5 ~ 6天，Fuerte品种的1 ~ 2天胚囊中只有不到20%的胚囊被花粉管穿透，尽管在珠被或珠心中经常观察到花粉管。在品种Hass中，超过60%的胚囊被穿透。在得出的结论是，低产量的品种Fuerte可能部分归因于失败的花粉管穿透胚囊。
Pollen tube growth, fertilization and early embryo and endosperm development were studied using light microscopy in the avocado varieties Fuerte and Hass.The ovule was penetrated by a pollen tube by 24 h after pollination. On reaching the ovary, the pollen tube grew along the surface of the inner ovary wall. It then grew around the funicle, through the micropyle in the inner integument and between the papillate cells at the apex of the nucellus. It entered the embryo sac via a synergid. Sperm nuclei were present in the embryo sac at 48 h after pollination and fusion of the polar and sperm nuclei took place before fusion of the egg and sperm. The endosperm nucleus was the first to divide and cell wall formation occurred following division. The first division of the zygote occurred at 5 or 6 days after pollination.In the variety Fuerte less than 20 per cent of the 1- and 2-day-old embryo sacs had been penetrated by a pollen tube although tubes were often observed in the integument or nucellus. In the variety Hass over 60 per cent of the embryo sacs were penetrated. In was concluded that low yields of the variety Fuerte may be partly attributable to the failure of the pollen tube to penetrate the embryo sac.