Genetics and introgression of resistance to root-knot nematodes (Meloidogyne spp.) in common bean (Phaseolus vulgaris L.)

M. Di Vito, B. Parisi, A. Carboni, P. Ranalli, F. Catalano


Genetics studies on the resistance to Meloidogyne spp. in common bean (Phaseolus vulgaris L.) were carried out in a glasshouse. F1 hybrids and F2-F4 progenies, derived from crosses of the Mesoamerican resistant accessions A#445 and PI#165426 with CRA-ISCI lines 212/28 and 15/7-70, were evaluated for resistance to Italian populations of Meloidogyne incognita race 1 and M. javanica. All F1 hybrids were resistant to both nematode species. Ninety-eight, 17 and 136 F2 lines were resistant, susceptible and segregant to the nematodes, respectively, and 1909 and 655 plants were resistant and susceptible, respectively. The results suggest a monogenic dominant control of the resistance, with a ratio 3:1 of resistant to susceptible plants. Of the 52 selected F4 lines tested for their reaction to race 1 of M. incognita, 22 were resistant, 24 segregant and six susceptible. Of the 52 F4 lines tested against M. javanica, 31, 11 and 10 were resistant, segregant and susceptible, respectively.

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