Comparative Resistance as Function of Physical and Chemical Properties of Selected Faba Bean Promising Lines against Callosobruchus maculatus Post Harvest

Abstract

The present investigation was conducted during two growing seasons 2015/2016 and 2016/2017 at Sakha Agricultural Research Station farm, in order to evaluate thirteen faba bean genotypes to physical and chemical properties against insects attack to faba bean seed from breeding program, under early and late sowing dates (mid-October and mid- November, respectively) comparing with three varieties were assessed to study their response to infestation with Cowpea weevil Callosobruchus maculatus post- harvest through storage under laboratory conditions. Susceptibility index (SI), Seed yield /plant as well as net weight after discarding the all negative factors which affect the final yield were taken as gauge of susceptibility of studied lines. Actually, the results indicated that the studied lines greatly differed to the attack of C. maculatus. According to (SI)i.e. the line with high values of SI, high number of progeny, weight losses and shorter life cycle were classified as susceptible. In contrast, the lines with intermediate S.I (5.1-7.5) and revealed lower number of adults emerged (lower, weight loss and longerlife cycle were considered tolerant or moderately resistant (MR). The results clearly indicated that the complete resistant lines were relatively absent. Furthermore, appositive relationship was fond between the physic-chemical characters and infestation with C. maculatus. According to S.I, seed yield/plant, net weight the lines 2 and 16 were the most tolerant, while line 14 and 4 were the most susceptible one. In addition, that the mid October was the suitable sowing date where it actualized the higher seed yield along the two planting seasons. Based on the highest net weight %, the line 2 and Sakha3 may be recommended to plant at mid-October and for storage at long periods where they were tolerant against the tested beetle in storage, some diseases in field and climatic sowing. In order to early maturity character, the promising breeding line 2 as an early mature faba line that characterizes with tolerant to insect infestation along with high yield potential, especially under the stresses associated with early sowing date. Therefore, it should be taken into consideration to select the promising line 2 for faba bean breeding program to improve productivity and tolerance to insect infestation to avoid insecticide usage. In conclusion, this investigation showed the importance of physical and chemical properties for protects the seeds of faba bean against the insect attack.