Verifying the hybrid nature in breeding common beans against Meloidogyne javanica using microsatellite markers

Abstract Background Root-knot disease caused by Meloidogyne spp. can severely impact common bean (Phaseolus vulgaris L.) yield. The breeding program typically commences by selecting parental lines and self-pollinating F1 plants. Identifying hybrid or off-type progeny is uncomplicated; however, identifying the true hybrid progeny within self-pollinated plants is challenging without the possibility of segregation analysis of molecular markers. Methods To develop segregating populations associated with M. javanica race one and M. incognita race two, Alabama #1 was crossed with six susceptible bean cultivars. Results Emasculated flowers (474) were pollinated as biparental crosses, and 55 pods of common bean were obtained, indicating a crossing success rate of 11.6 %. Among the nine single sequence repeat (SSR) markers, BM175, BM154, BM157, BM184, and BM143 were polymorphic among genotypes. These polymorphic markers were used to determine the hybrid nature of F1 plants. These markers revealed that 19 out of the 81 seeds were not true hybrids. The hybridization rate was estimated to be 76.54% in the F1 seeds after successful mating and one plant from the Black Valentine ×Alabama#1 crossing was hybridized, showing the most reduced hybridization rate. Conclusion As the hybrid nature of this case could not be identified with morphological traits. Therefore, molecular markers, especially SSRs, because of their unique characteristics have a suitable resolution to detect the true-off type and genetic purity in seed production, and can be successfully used in common bean breeding programs.