四倍体番茄低稔性胚胎学研究

Studies on the Mechanism of Low Fertility in Induced Tetraploids of Tomato

本试验通过详细观察四倍体番茄自交受精过程及胚胎发育,对四倍体番茄稔性低的原因进行了初步探讨,得到以下结果:(1)四倍体自交时,花粉萌发率低,花粉管生长较慢且不整齐;(2)受精前,四倍体有个别胶囊结构外观异常的胚珠,但这不是导致受精胚珠率低的主要原因;(3)四倍体自交时,受精正常,只是受精时间略迟,有花粉管进入的胚珠数明显比二倍体自交的低;(4)受精胚珠能正常发育成饱满种子.分析表明,四倍体番茄稔性低的主要原因是胚珠受精率低.本文还对受精率低及导致低稔性的原因进行了探讨.

The low fertility of tetraploid tomato self-cross (4x× 4 x)was studied. The comparative histological studies of the fertilization and embryogenesis of the self-crosses (2x× 2x and 4x× 4 x) were reported.1 . The frequency of pollen germination was relatively low and the pollen tubes grew slowly and nonuniformly in the cross 4x× 4 x.2 . The abnormal ovules were occasionally observed in the tetraploid before fertilization.3 . Fertilization proceeded normally except that the fertilization was somewhat delayed and that the percentages of ovules into which pollen tubes got was significantly low in the mating 4x × 4x.4 . The developing seed of the tetraploid resembled that of the diploid very closely.5. Analysing the data on the fertilization and embryogenesis of tetraploid showed that low fertility of tetraploid was attributed to the low frequency of fertilized ovules.