Evaluation of different Ethiopian common bean, Phaseolus vulgaris (Fabaceae) genotypes for host resistance to the Mexican bean weevil, Zabrotes subfasciatus (Coleoptera: Bruchidae)

Abstract

Common bean (Phaseolus vulgarisL.) is amongst the most important grain legume crops in Africa in general, and Ethiopia in particular. The Mexican been weevil (Zabrotes subfasciatusBoheman) heavily attacks the grain of common bean. A total of 300 common bean entries were subjected to a ‘no-choice’ test at Melkassa Agricultural Research Centre, Ethiopia, using a randomized complete block design with three replications, to evaluate for resistance to the Mexican bean weevil. Data on insect and seed traits were collected and a significant level (P<0.01) of variation in all parameters measured was observed amongst genotypes. Relative resistance was recorded in landraces, improved genotypes and breeding lines, but the resistant genotypes, RAZ-11, RAZ-36, RAZ-2, RAZ-44, RAZ-120, RAZ-40 and MAZ-203, showed consistently complete resistance, with zero index of susceptibility value. Two other promising entries were also identified from the breeding lines (SCR-11) and landrace collections (NC-16) of Ethiopia. Stratified ranking diagrams showed that accessions from different eco-geographical origins in Ethiopia and those with different colours showed different patterns of response to infestation. The Ethiopian bean breeding programme should take up the resistant genotypes for a comprehensive yield trial at the national level and direct release them as commercial varieties. The incorporation of bean weevil resistance genes into adapted varieties through backcross breeding techniques, supported with marker assisted selection, seems to be the best strategy not only in terms of time saving but also in terms of effectiveness and efficiency.

Population Development of Bean Weevils (Coleoptera: Chrysomelidae: Bruchinae) in Landrace Varieties of Cowpeas and Common Beans

“…The bean weevil population development patterns observed in landrace varieties from the southwestern Amazon region indicate the existence of sources of resistance to bean weevils in the tested varieties. Some authors have reported variations in susceptibility to bean weevils in different varieties of cowpea and common bean (Cruz et al 2015;Tigist et al 2018). In this study, C. maculatus and Z. subfasciatus population development rates were substantially lower in the cowpea UFAC-Q01 and the common bean UFAC-R01 varieties, respectively.…”

“…A major factor influencing common bean and cowpea yields is attack by pests, particularly the bean weevils Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) and Zabrotes subfasciatus (Boheman) (Coleoptera: Chrysomelidae), respectively. Larvae of these insects cause damage by penetration and by feeding on the cotyledons (Melo et al 2015;Tigist et al 2018).…”

Breeding potential of lablab [Lablab purpureus (L.) Sweet]: a review on characterization and bruchid studies towards improved production and utilization in Africa

“…Varietal resistance to pest attack is the most appropriate method since it is efficient, affects target organisms only, sustainable and reduces the cost of production. Studies on host plant resistance to bruchids have been undertaken in soybean (Msiska 2019), common bean (Maro 2017;Tigist et al 2018), cowpea (Weldekidan 2019), mung bean (L.) R. Wilczek (Somta et al 2006) and pigeon pea (Cajanus cajan L.) Millsp.) (Mishra et al 2019).…”

On-Farm Diversity of Common Bean (Phaseolus Vulgaris L.) Varieties in East Hararghe Zone, Eastern Ethiopia

“…Even though the productivity of farmers' varieties is lower than improved varieties, their local demand is often high because they are required for the preparation of cultural foods and they are more reliable under a wider range of conditions (Bethelem et al 2020). In addition, Farmers' traditional varieties, or landraces, have been selected for speci c agro-ecological niches and in some cases have been shown to better resist insect pests, diseases and climate shocks, as well as meet the nutritional and cultural needs of Ethiopia's diverse farming communities (Tigist et al 2018). Despite the signi cance of Ethiopia's legume diversity, it remains largely unstudied and unmonitored (Ruelle et al 2019) in general and in east Haraghe Zone in particular.…”