PJB-2018-676
Anatomical and histochemical observation of microspore abortion and tapetum degeneration in male-sterile Rosa steriliser S. D. Shi (Rosaceae)
Xing-Yin Chen, Ping Guan, Jian-Ming Shi, Peng Yang and Kai-Kai Zhang
Abstract
A high frequency of pollen grain abortion causes male sterility in Rosa sterilis S. D. Shi. To study the cytological mechanism of male sterility in R. sterilis, we compared microspore development and histochemical distribution of nutritive materials at different stages of anther development in R. sterilis and its fertile close relative Rosa roxburghii Tratt by light microscopy. The pollen mother cells of R. sterilis and R. roxburghii develop consistently, and undergo normal meiosis. At the tetrad stage, the tapetum cells of R. sterilis showed binuclearte and trinucleate augmentation and no signs of degeneration, whereas R. roxburghii showed evidence for initiation of tapetum degeneration. At the vacuolate microspore (VMP) and mature pollen stages, the nucleus degenerated in R. sterilis microspores, resulting in empty pollen grains. Non-nucleate microspores comprised 76.70% of total microspores in late-VMP anther of R. sterilis, but only 2.4% in R. roxburghii anthers. The distribution of nutritive materials in R. sterilis and R. roxburghii anthers showed no notable differenc at the meiosis stage, except for that of starch grains. At the mature pollen stage, nutritive materials (protein, polysaccharides, starch grains) accumulated in R. roxburghii pollen grains, whereas nutrients failed to accumulate in R. sterilis pollen grains. The delayed disintegration of the tapetum and lack of accumulation of nutritive material may be cause of pollen abortion in R. sterilis. late VMP stage is a critical period for R. sterilis pollen abortion. Nuclear matter melted was the key factor resulting in pollen abortion of R. sterilis.
To Cite this article:
Chen, X.Y., P. Guan, J.M. Shi, P. Yang and K.K. Zhang. 2020. Anatomical and histochemical observation of microspore abortion and tapetum degeneration in male-sterile Rosa steriliser S. D. Shi (Rosaceae). Pak. J. Bot., 52(3): DOI: http://dx.doi.org/10.30848/PJB2020-3(28)
Download
