温度对斯托克通氏烟草雄配子体形成和发育的影响

Effects of temperature on Nicotiana stocktonii during microsporogenesis

关键词:  斯托克通氏烟草  温度  雄配子体形成  异常现象

Key words:  Nicotiana stocktonii  temperature  microsporogenesis  abnormality

摘要:

为探究低温对斯托克通氏烟草(Nicotiana stocktonii)花粉母细胞(PMC)减数分裂及其雄配子体发育过程的影响,采用卡宝品红染色法,研究不同温度条件下该材料雄配子体形成和发育的过程。结果表明:种植于昼温(31±0.5)℃、夜温(11±0.5)℃人工气候箱中的Nicotiana stocktonii花粉母细胞减数分裂过程异常现象较少,出现微核的比率较低,用新鲜成熟的花粉做萌发实验花粉萌发率较高,为(71±3)%; 而种植于昼温(25±0.5)℃、夜温(3±0.5)℃条件下的Nicotiana stocktonii开花后花药大多干瘪,用新鲜成熟花粉做萌发实验花粉萌发率低,为(13.67±3)%,花粉母细胞减数分裂过程出现染色体桥、染色体不同步、染色体断片、落后染色体等现象,存在微核的细胞比率较高。因此,Nicotiana stocktonii花粉母细胞减数分裂与小孢子发育过程易受温度影响,从而影响花粉的可育性。

Abstract:

In order to explore the influence of temperature on the meiosis of pollen mother cells and microsporogenesis in Nicotiana stocktonii,materials planted at different temperatures were observed by carbol fuchsin staining. The results showed that there was less abnormality and lower microkernel ratio during meiosis of pollen mother cells and microsporogenesis when N. stocktonii was planted at higher temperature. Anther of N. stocktonii planted at lower temperature withers and the pollen germination rate was low,10%-15%,compared with the 65%-75% germination rate of materials planted in higher temperature. In addition,there were chromosome bridges,chromosome out of sync,chromosome fragment,laggard chromosome and higher micronucleus ratio during meiosis. It can be concluded that N. stocktonii meiosis of pollen mother cells is impressionable to low temperature and inevitably affected the fertility of pollen.