红桔小孢子母细胞减数分裂染色体行为的研究

本研究对红桔小孢子母细胞减数分裂各时期染色体进行了详细观察。结果表明：细线期、偶线期、粗线期和终变期具有较高的同步性，四分体时期完全一致；染色体行为较为有规律；双线期同源染色体联会构型有棒形、环形、“Ｔ”形、“＋”字形、环叉形及“３”字形；终变期具９个正常二价体的频率为６０％，其余细胞中可观察到单价体、双核、落后染色体、三分体等畸变类型。文章讨论了红桔花粉低育性的遗传学机制。

Studies on the Chromosome Behaviour in Meiosis ofMicrosporocyte in Citrus tangerina

The detailed observations of chromosome behaviour in meiosis of microsporocytesat all stages for Citrus tangerina were made. The results showed that the meiosis atleptotene,zygotene,pachytene and diakinesis stage appear highly synchronic,and at tetradstage appears completely synchronic. The chromosorne behaviour was comparativelyregular.The chromosomal configurations at diplotene stage are rod-shaped,ring-shaped,T-shaped,cross-shaped,ringcross-shaped and 8-shaped.The frequency of PMCs with 9normal bivalents is about 60% at diakinensis. However,the various abnormalities ofchrornosome behaviour could be noticed, including univalents,binucleates,laggards,triadetc,The genetic mechanism of low fertility in C. tangerina pollens was also discussed.