SELECTION WITHIN F2 THROUGH F4 FOR EARLINESS AND PRODUCTIVITY IN FABA BEAN (Vicia faba L.)

Abstract

This work was conducted in the Experimental Farm of Mattana Agricultural Research Station, Agricultural Research Center, Egypt, during two successive winter seasons of 2008/2009 and 2009/2010 to study the responses to two cycles of selection from the offspring of three crosses among local cultivars with variable levels of earliness and high yielding ability. Four cultivars of faba bean i.e. Giza-716, Giza-843, Sakha-1 and Triple White were crossed to attain the goal of this study. In the first season of 2008/2009, mean performances of the four parents and their offspring of F2 generation for seed yield per plant and number of days from sowing to maturity were measured in order to make the best choices of populations of high yielding ability and earliness. The results showed that three of six populations attained the best results of the critical traits i.e. Sakha-1 × Giza-843, Sakha-1 × Giza-716 and Giza-843 × Triple White. In the first season of 2008/2009, the responses to selection were measured at the levels of six out of eight traits because there were insignificant differences between the bulk and the selected populations for both numbers of days from sowing to flowering and maturity of the selected F3 families. Plant height insignificantly varied among the 3 populations and ranged from 109.1 to 119.1 cm. and number of branches per plant from 4.47 to 7.07 branches. However number of pods per plant insignificantly varied among the 3 populations and ranged from 36.7 to 53.9 pods and number of seeds per plant from 95.7 to 100.8 seeds. Although the analysis of variance indicated insignificant variations among the 3 populations selected of F3 for number of pods and seeds/plant, the responses to selection for both traits were very high. Weight of seeds (g) per plant of the selected F3 families considerably varied among the 3 populations and ranged from 59.16 to 105.13 g and also the response to selection was so high and reached a convenient level to continue for further cycles of selection. Weight of 100 seeds relatively varied among the 3 populations from 62.1 to 80.9 g. In the second season of 2009/2010, the means of all eight traits of the selected F4 families were calculated and the responses to selection were measured with similar results as those of the selected F3 families. The population Giza-843 × Triple White has achieved the goal of the research as it exhibited high productivity with good level of earliness indicating the importance of proper choice for the germplasms selected in breeding programs. The results obtained encouraged the team work to continue the research on the three selected populations in advanced cycles of selection to improve the performance of faba bean plants.