The Podostemaceae family is exceptional among angiosperms because of the absence of double fertilization, a remarkable characteristic that appears to extend to the entire family. A recent investigation of some members of the family, including Dalzellia zeylanica (Tristichoideae), Griffithella zeylanica, Polypleurum stylosum, Zeylanidium lichenoides, and Zeylanidium maheshwarii (Podostemoideae), revealed that the central cell in all of them is degenerated when the pollen tube arrives at the synergid. In the present work, we studied the ontogenetic development of the female gametophyte. We also conducted a terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and an ultrastructural transmission electron microscopy (TEM) analysis of Marathrum schiedeanum (Podostemoideae) to determine the causes of central cell degeneration. The results show that in the early stage, the female gametophyte was 4-celled and 4-nucleated, but the central cell degenerated very quickly before the start of anthesis. The reduced mature female gametophyte is 3-nucleate, 3-celled. TUNEL staining and ultrastructural TEM analysis indicated that developmental programmed cell death (PCD) mediated the degeneration of the central cell. The central cell displayed a significant quantity of vacuoles containing some cellular material, and the compact chromatin was present in the nucleus and DNA fragmentation occurred. The factors that trigger PCD in the central cell are unknown, but the test results confirm that pollination is not necessary for it to occur. The death of the central cell before pollination prevents the possibility of double fertilization and consequently results in failure to form the endosperm.

由于没有双重受精，Po科植物在被子植物中是特殊的，这种显着特征似乎扩展到整个家庭。最近对该家族的一些成员进行了调查，包括Dalzellia zeylanica（Tristichoideae），Griffithella zeylanica，Polypleurum stylosum，Zeylanidium lichenoides和Zeylanidium maheshwarii（Podostemoideae），揭示了当花粉管到达协同体时，所有中央细胞都退化了。在目前的工作中，我们研究了雌配子体的个体发育。我们还进行了Marathrum schiedeanum的末端脱氧核苷酸转移酶dUTP缺口末端标记（TUNEL）分析和超微结构透射电子显微镜（TEM）分析（Podostemoideae）确定中央细胞变性的原因。结果表明，雌配子体在早期阶段是4细胞和4核的，但中心细胞在花期开始之前很快就退化了。减少的成熟雌配子体是3核3胞。TUNEL染色和超微结构TEM分析表明发育性程序性细胞死亡（PCD）介导中央细胞的变性。中央细胞显示大量含有某些细胞物质的液泡，并且紧密的染色质存在于细胞核中，并发生了DNA断裂。触发中心细胞中PCD的因素尚不清楚，但测试结果证实，授粉不是必需的。