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马尾松雌、雄球花的形态发育

A STUDY ON MORPHOLOGICAL DEVELOPMENT OF MALE/FEMALE FLOWERS OF MASSON PINE

  • 摘要: 本文报道了马尾松雌、雄球花的形态变化与发育进程。①雄球花(即小孢子叶球):雄球花芽聚生于当年春梢基部,外被芽鳞,芽鳞张开球花显露。小孢子囊由表皮、中间层、绒毡层和造孢组织组成。绒毡层细胞是双核的。小孢子四分体为四面体形和对称形。单核花粉时期花粉外壁延伸成2个大小相同的气囊;成熟花粉具2个原叶细胞、1个生殖细胞和1个管细胞。②雌球花(即大孢子叶球):雌球花芽着生于当年春梢顶端,顶部芽鳞张开后雌球花显露。珠鳞以螺旋状排列在球花中轴上,腹面着生两枚倒生胚珠。胚珠由珠被和珠心组成,单珠被,受粉时珠鳞张开;珠心内含1或2个大孢子母细胞。雌球花各发育阶段的出现时间,均较雄球花迟。

     

    Abstract: In this paper morphological change and development procedure of male/female flowers of masson pine was reported as follows: ① Male flowers: Male flowers, which were covered by bud scales, aggregated on the lower part of new shoot. It was found that male flowers were naked with scales open. Gynospore sac consisted of epidermis, middle layer, tapetum and sporogenous tissue. Tapetal cell was binucleated and gynospore quadrent was quadritaloral and symmetrical. During monokaryon phase the exhymenine stretched and produced two air sacs of same size. A mature pollen contained two vegetative cells, one generative cell and one tube cell.② Female flowers: Female flowers were at the top of new shoot, and after the top bud scales opened, the female flowers revealed. The ovule scales, in the rear of which there were two anatropous ovules, arranged in the form of a spiral. The ovule consisted of integuments and nucellus, the former with one layer of tissue and ovule scales open when pollinated, and the latter contained one or two macrosporocytes. The appearance of the development of female flowers was later than that of the males in different phases.

     

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