Diallel crosses of genetic enhancement for seed yield components and resistance to leaf miner and aphid infestations of Vici faba L.
Mohamed Abd El-Hamid S. El-Bramawy, Mohamed Abd El-Naeim M. Osman
Key words: Diallel crosses, insect resistance, genetic enhancement, yield components, Vicia faba.
The genetic parameters for seed yield with its components and the resistance to infestations by some insect pests viz., Liriomyza congesta and Aphis craccivora were assessed in complete diallel crosses between six parents of faba bean. Highly significant differences among the six parents and their offspring F1s were detected in all investigated characters. Positive general combining ability (GCA) effects for high potential of seed yield with certain components and high resistance to L. congesta and A. craccivora were found in BPL 710, Sakha 1 and Nubaria 1. The ratio of general and specific combining ability (GCA/SCA) indicated that there were great additive effects for the majority of the studied characters. Heritability values in bored sense were relatively high and passed 75% for maturity date, number of branches per plant, chlorophyll content, total shedding percentage, seed yield per plant, number of L. congesta mines and larvae/100 leaflets and number of Aphis craccivora individuals/100 leaflets, confirmed the importance of selection for these characters. The ratio of dominance (KD)/recessive (KR) alleles was less than one for all the studied characters, except the number of aphid individuals/100 leaflets. The correlation between parental performance (Yr) and parental order of dominance (Wr+Vr) was positive for number of pods per plant, 100-seed weight, chlorophyll content, total shedding percentage as well as the number of L. congesta mines and larvae/100 leaflets. This indicated that the faba bean parents possessed mostly negative genes in dominant form, while for the remaining characters, positive genes were mostly dominant.
Read Full Article: Volume 2, Number 2, February 2012 – IJAAR