太谷核不育小麦可育花药内游离脯氨酸的来源、利用及与不育花药败育的关系

太谷核不育小麦营养体内的游离脯氨酸能迅速地运入并积累于花药中,花药有将谷氨酸转化成脯氨酸的能力。脯氨酸向花药内以主动运输为主,能被DNP所抑制,与旗叶的功能密切相关。在发育阶段Ⅰ(小孢子释放前后),脯氨酸已不能由营养体运入不育花药,运输的障碍在花丝或花药中,不育花药缺乏游离脯氨酸可能是主要原因。发育阶段Ⅰ的可育花药内,脯氨酸是合成蛋白质或其他大分子物质的原料。因而,脯氨酸的缺乏可能是加速不育花药小孢子败育和小孢子释放后急剧解体的重要原因。

THE SOURCE AND UTILIZATION OF PROLINE IN ANTHERS OF NORMAL TAIGU WHEAT PLANTS AND THEIR POSSIBLE RELATION TO THE ABORTION OF STERILE ANTHERS

Feeding experiments with ~3H-proline and infiltration experiments with ~3H-glutamic acid into anthers were carried out to study the source of proline in ferile anthers, the ability of anthers to convert glutamic acid into proline, the physilogical role of proline in the development of microspores and the possible cause of abortion in sterile anthers. The following results were obtained. (1) In fertile anthers, the free proline accumulated came mainly from the vegetative parts of the plants; however, the anthers themselves also possessed some ability of converting glutamic acid into proline, especialy at binucleate stage when the anther walls had turned green. This synthetic activity might be attributed to the chlorophyll-containing tissues. The transport of proline from the vegetative part to anthers was an active process. It was inhibited by 2,4-dinitrophenol, and it was closely connected with the function of flag leaves. (2) In sterile anthers the transport of proline from the vegetative parts was greatly hindered, and this might be the cause of proline deficiency in sterile anthers. (3) Entry of proline from the vegetative parts into the pistils of sterile plants was perfectly normal, suggesting that in the process of gene expression of Ta_1, some physiological barriers appeared in the anthers or filaments, preventing the entry of proline into the anthers. (4) In fertile anthers near microspore releasing stage, free proline administrated could serve as raw material for the synthesis of proteins or other physiologically active substances with large molecular weight. It appears that deficiency of free proline in sterile anthers can directly affect the formation and development of the microspores, which probably speed up the abortion of microspores or their rapid collapse,but the deficiency in free proline is not the primary cause of the microspores abortion in the sterile anthers.