Liu Xueqing, Yu Xiaoqian, Yang Ling
State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China.
College of Forestry, Beijing Forestry University, Beijing 100091, China.
Plants (Basel). 2025 Feb 20;14(5):637. doi: 10.3390/plants14050637.
In this study, the morphological and anatomical characteristics of the growth of the internal ovules and the dynamic changes in the content of endogenous hormones during the development of Korean pine ( Siebold & Zucc.) cones were investigated in detail and their interrelationships determined. In addition, morphological examinations, paraffin section, analysis and enzyme immunoassays were performed to observe the growth and development as well as the fertilization stages of the ovules of from July of the pollination year to June of the following year. From July of the pollination year to May of the next year, the increase in the content of indoleacetic acid (IAA) and gibberellin and a decrease in the content of abscisic acid (ABA) in the pollination year correlated with the division of the gametophyte free nuclei. It was observed that the levels of IAA, ABA, zeatin riboside (ZR) and isopentenyl adenosine (IPA) initially decreased and then increased during overwintering, which was interpreted as a symptom of adaptation of ovules to low temperatures. At the end of overwintering, the increase in IPA, ZR and ABA levels was associated with the development of the female gametophyte. The week before fertilization was identified as the stage of oocyte division, in which growth-promoting hormones dominate. During the week of fertilization, the increase in the level of growth-inhibiting hormones correlated with fertilization. After fertilization, the increase in the level of growth-promoting hormones also correlated with early embryonic development. The levels of endogenous hormones were observed to change dynamically with the development of oocytes, indicating their important role. The results of this study provide the morphological and anatomical basis for related studies on the development of the ovarian strobilus in gymnosperms.
本研究详细调查了红松球果发育过程中内部胚珠生长的形态和解剖特征以及内源激素含量的动态变化，并确定了它们之间的相互关系。此外，还进行了形态学检查、石蜡切片、分析和酶免疫测定，以观察从授粉年7月到次年6月胚珠的生长发育以及受精阶段。从授粉年7月到次年5月，授粉年中吲哚乙酸（IAA）和赤霉素含量的增加以及脱落酸（ABA）含量的降低与雌配子体游离核的分裂相关。观察到在越冬期间，IAA、ABA、玉米素核苷（ZR）和异戊烯基腺苷（IPA）的水平最初下降然后上升，这被解释为胚珠适应低温的症状。在越冬结束时，IPA、ZR和ABA水平的增加与雌配子体的发育相关。受精前一周被确定为卵母细胞分裂阶段，在此阶段促进生长的激素占主导地位。在受精周期间，生长抑制激素水平的增加与受精相关。受精后，促进生长的激素水平的增加也与早期胚胎发育相关。观察到内源激素水平随着卵母细胞的发育而动态变化，表明它们具有重要作用。本研究结果为裸子植物雌球花发育的相关研究提供了形态和解剖学基础。
