K型温敏雄性不育系KTP116A育性转换规律的研究

基于两系杂交小麦系统的K型（Aegilops kotshyi）细胞质小麦温敏雄性不育系，在中国北方小麦正常生长季节表现完全雄性不育，可用于杂交小麦种子生产，在反季节播种表现育性部分恢复，是一类非常有利用价值的小麦温敏雄性不育系。本研究以小麦温敏雄性不育系KTP116A为材料，采用人工气候箱控温和涂抹法压片的方法对其育性转换的关键时期及败育的花粉发育过程进行更为精细的研究。研究发现，KTP116A可育环境下能正常进行减数分裂并发育为成熟花粉粒；不育环境下只有少数能经过第二次有丝分裂产生两个精细胞，大部分为二核期花粉粒、异常花粉粒和没有原生质体的空壳花药不开裂，自然条件下不散粉；KTP116A育性敏感期为两个时期，减数分裂期至单核早期和二核晚期至三核期，在自然条件下温度感应历期为10d左右；从小麦外部发育进程来看，抽穗前的2-8d和扬花前的3-5d为其敏感时期。这对于进一步研究败育的机理，分析败育的原因和更好的利用温敏不育系奠定基础。

Study of fertility changes on K-type thermo-sensitive male-sterile wheat line KTP116A with Aegilops kotshyi

Abstract: K Type thermo-sensitive Cytoplasmic male sterile wheat which was based on two-line hybrid wheat ,could produce hybrid wheat seeds because of its completely sterility in normal wheat growing season of northern China, but fertility restored partly in anti-season seeding . This study has made a more fine research on the fertility-conversion critical period, abortion of pollen development process of KTP116A and K116A by using artificial climate chamber and the smear method. The results showed that KTP116A can carry the normal meiosis and develop into mature pollen grains under fertile environment; but in sterile environment, only a few can go through the second mitosis and produce two sperm cells, most of the them are arrested at binucleate grain, abnormal pollen grains and shell anthers without protoplast; two fertility sensitive periods of KTP116A were from meiosis to early microspore and binucleate to trinucleate, corresponding to 2-8d before heading and the 3-5d before flowering. Temperature sensitive stage is about 10d. These findings will make a foundation to further study of abortion mechanism, aboration reasons analyzing and the better use of TCMS.