Study of Some Characteristics Related to the Sexual Reproduction in Autotetraploid Vicia narbonensis

Abstract

<p>Some parameters such as frequency of pod formation, average number of seeds per pod and percentage of empty<br />pods were used to evaluate the variation of fertility in autotetraploid Vicia narbonensis. The results showed that<br />the autotetraploid and diploid parents had the same number of ova per gynaecium. However, the tetraploid<br />seedling produced fewer seeds per pod and per seedling than their corresponding diploids; the poor fertilization<br />of many ovum was probably behind the decline of fertility in the autotetraploids. Several factors may be<br />involved: the low efficiency of diploid pollen (related to a relatively slow growth of the pollen tubes), an<br />unbalanced meiosis for a great number of mother cells of pollen grains and a significant morphological<br />modification of the reproductive system due to the passage from the diploid to the tetraploid state.</p