Selection for Earliness, Yield and Its Components Within Segregated Generation of Broad Bean Hybrids

Abstract

The present study was carried out during the three successive winter seasons of 2016/2017, 2017/2018 and 2018/2019 in experimental farm of Sabahya, Horticulture Research Station, Alexandria Governorate, Egypt. Selection with self-pollination was conducted for space two isolation of broad bean, produced from cross (P1: Reina mora × P2: Giza planka) and cross (P2: Giza planka× P1: Reina mora). Two methods of selection were used, namely mass selection and individual selection of some important characteristics associated with early yield and high productivity of the crop. In the third season (winter season of 2018/2019), the parents and their selected plants from cross first and second selected generation either mass or individual selection were evaluated. To measure the amount of progress in yield and its components and early yield traits of broad bean for two cycles in both selection methods, in addition to a comparison between the progress in using the mass and individual selection and documenting the difference between progress using both methods The obtained results are summarized as follows: There were significant differences between all strains in all traits under study. There was superiority of the second selected generation and the check cultivar over the original population. There was a remarkable superiority of the strains resulting from the mass selection over the strains produced from the individual selection, as the most of the strains achieving the highest values ​​were within the mass selection strains, but from the reality of the standard deviation values (± SD), in general for each selection generation, it was in the interest of the second individual selection generation strains which produced superior strains overall selection generation, indicating that the individual selection is more effective in increasing homogeneity with line. Regarding phenotypic and genotypic coefficient of variance range between them were close in the most traits, these values were in agreement with heritability estimates which being the highest in the same traits. Inbreeding depression were occur in some flowering traits, however, their were good direction for decreasing in is trait and a big role in yielding improvements. Regarding genetic advance from selection, the total fresh yield followed by total dry yield, achieving the highest values ​​compared to the remaining of the traits. Values of genetic advance as percentage of mean were higher in the first cycle of mass selection than the second one in the most of the characters. This indicates that the genetic advance as percentage of mean, decreased by increasing in selected generation.