Studies On Cytology And Physiological&Biochemical Characteristics Of Male Sterile Plants In Nitraria Roborowskii Kom

With floral organ of the male sterile plants and fertile plants of Nitraria roborowskii Kom.which distributed in Dengkou county of Inner Mongolia were taken as tested material in this experiment. The microscopic structure and ultrastructure of anther at different developmental stages were observed and researched to explore the period,methods,and cell ultrastructure changes and relationship between male abortion and the anther wall as well as the change of ultrastructure.The physiological&biochemical characteristics of anther were analysised and researched to explore the relationship between metabolism and male sterility in abortion of the male sterile plants.The result as follows:1. There was no obvious difference in plant height, plant width and number of branches between the male sterile plants and fertile plants of Nitraria roborowskii-Kom.. The flowers of the male sterile plants compared to fertile plants were smaller; with white corolla with a light green and very short filaments; anthers were thin and shriveled, which early stage showed pale yellow, but late into brown, not crack, and no pollen shed. Filaments of fertile plants are longer; anthers are plump and yellow, and entire anther cover with pollen after anthers crack. It could be observed by naked eyes that the style of the male sterile plants lengthenes and more shorter than fertile plants, and individual swelling at the front-end. Pistil function is normal and produces many seeds.2. The microspore of male sterile plants of Nitraria roborowskii Kom. abortion occurred soon after the formation of the microspore mother cells,it caused by the early disintegration of the tapetum, including microsporocytes, middle layers, endothecia and connectivum cells vacuolization, malformation, anther wall’s abnormal breakup, etc. After those, the whole anther withered, couldn’t crack and wouldn’t produce pollen. With the electron microscope,the results showed that there were unusually large vacuoles in tapetum and microspore mother cells, and abnormal disintegration of the nucleus and organelles, there was no ubisch bodies in the chamber.3. Physiological and biochemical tests results showed that:the soluble protein showed a downward trend in the floral organ of the male sterile plants and fertile plants of Nitraria roborowskii Kom..The difference of content is obvious of in early stage; the proline content of male sterile plants floral organ is lower than the same period in the fertile plants, with the development of microspore showed a constantly decreasing trend and fertile plants showed an upward trend; POD activity and MDA levels were higher than the same period in the fertile plants. The results suggested that:the reduction of substance&energy metabolism, accumulation of harmful substances were existed in male sterile plants.