Yao Peng-Qiang, Xie Li-Hua, Li Mei-Yu, Jiao Si-Qian, Qi Shuai-Zheng, Wang Zhe, Cheng Shi-Ping
Henan Key Laboratory of Germplasm Innovation and Utilization of Eco-Economic Woody Plant, Pingdingshan University, Pingdingshan, 467000, China.
Chromosome Res. 2024 Dec 2;32(4):15. doi: 10.1007/s10577-024-09759-7.
Triploids play an important role in the polyploidization process and are considered a bridge between diploids and polyploids. To inform plant polyploidization research and polyploid breeding, it is important to explore chromosome behaviour during triploid pollen development, pollen fertility problems in triploids and the potential value of utilizing triploids. In this study, acetocarmine, carbol fuchsin and fluorescence staining methods were used to observe microsporogenesis and microspore development in fertile triploid Chinese chives. The results revealed that some of the pollen mother cells were able to undergo equal chromosome distributions (approximately 36%), whereas other pollen mother cells formed lagging chromosomes, chromosome bridges, micronuclei and early cytoplasmic divisions during microsporogenesis, resulting in microspores of different sizes. Regardless of whether an equal tetrad or an abnormal polyad was formed, microspores were released from callose in a normal manner and contained nuclei. During the process of microspore development, most of the microspore nuclei disappeared gradually and ultimately formed empty pollen cells that lacked nuclei. During the meiosis of pollen mother cells in triploid Chinese chives, a variety of chromosome distribution behaviours contribute to the formation of some viable pollen.
三倍体在多倍体化过程中发挥着重要作用，被认为是二倍体和多倍体之间的桥梁。为了为植物多倍体化研究和多倍体育种提供信息，探索三倍体花粉发育过程中的染色体行为、三倍体中的花粉育性问题以及利用三倍体的潜在价值具有重要意义。在本研究中，采用醋酸洋红、石炭酸品红和荧光染色方法观察了可育三倍体韭菜的小孢子发生和小孢子发育。结果表明，部分花粉母细胞能够进行染色体均等分配（约36%），而其他花粉母细胞在小孢子发生过程中形成落后染色体、染色体桥、微核和早期细胞质分裂，导致产生大小不同的小孢子。无论形成的是均等四分体还是异常多联体，小孢子都能以正常方式从胼胝质中释放出来并含有细胞核。在小孢子发育过程中，大多数小孢子核逐渐消失，最终形成无核的空花粉细胞。在三倍体韭菜花粉母细胞减数分裂过程中，多种染色体分配行为有助于形成一些有活力的花粉。
