Identification of candidate genes associated with resistance to bruchid (Callosobruchus maculatus) in cowpea

Abstract

Cowpea is an important legume crop widely grown in sub-Saharan Africa for food and feed. However, it is largely challenged by bruchid, a serious storage pest resulting in losses in quantity and quality of grains. Therefore, this research was designed to contribute to the breeding of cowpea resistance to bruchid through the identification of candidate genes associated with resistance to bruchid. A total of 217 mini-core cowpea accessions were genotyped and phenotyped for their reactions to bruchid. To determine the genomic regions linked with bruchid resistance, 41,948 polymorphic SNP markers were used. Genome-wide association study identified 11 SNPs linked to the average number of eggs, holes, insect emergence and development period and Dobie susceptibility index. Gene search via Phytozome identified six candidate genes (

Disparate genetic variants associated with distinct components of cowpea resistance to the seed beetle Callosobruchus maculatus

“…They identified six candidate genes associated with egg number, development time and insect emergence. None of the genes were on chromosome 5, where we found the strongest genetic association (Miesho et al, 2019). Two were on chromosome 8 (Vigun08g132300 and Vigun08g158000 ), but these genes differed from those found on chromosome 8 associated with early-exiting larvae in this study.…”

“…A variety of non-insecticidal techniques have been developed and employed to control C. maculatus, including cultural, biological, and physical methods (Solleti et al, 2008;Cruz et al, 2016;Amusa et al, 2018). One approach has been to develop broadly resistant cultivars of cowpea and other grain legumes by first establishing the genomic basis of resistance (Schafleitner et al, 2016;Miesho et al, 2019). Candidate genes and QTLs conferring grain-legume resistance have often been identified by analyses of progeny derived from crosses of resistant and susceptible lines (Souframanien et al, 2010;Chotechung et al, 2016;Kaewwongwal et al, 2017;Somta et al, 2018).…”

Molecular Fingerprinting and Hybridity Authentication in Cowpea Using Single Nucleotide Polymorphism Based Kompetitive Allele-Specific PCR Assay

“…This has facilitated the discovery of molecular markers for traits discovery and deployment in the breeding programs. For example, a number of studies have identified quantitative traits loci (QTLs) associated with resistance to biotic and abiotic stresses in cowpea (Muchero et al, 2009b;Agbicodo et al, 2010;Lucas et al, 2013;Huynh et al, 2015;Benoit et al, 2016;Essem et al, 2019;Miesho et al, 2019). However, although the application of molecular markers in hybridity testing and hybrid purity assessment have been demonstrated in several other crops (Patella et al, 2019a;Kishor et al, 2020;Osei et al, 2020), there is no documentation of its deployment in cowpea.…”

The UCR Minicore: a resource for cowpea research and breeding

“…This minicore was genotyped using the 51,128‐SNPs Cowpea iSelect Consortium Array (Muñoz‐Amatriaín et al, 2017) and the genotypic information was used to gain a better understanding of the genetic diversity of domesticated cowpea. Although this is the first summary report and full SNP data release for the UCR Minicore, this material has been utilized for more focused work on seed coat color (Herniter et al, 2018), seed coat pattern (Herniter et al, 2019), seed size (Lo et al, 2019), bruchid resistance (Miesho et al, 2019), plant herbivore resistance (Steinbrenner et al, 2020) and pod shattering (Lo et al, under review). This study evaluated additional traits of agronomic importance including flowering time, dry pod weight, dry fodder weight, and pod load score.…”