Population densities of Meloidogyne incognita and growth of susceptible and resistant pepper plants


  • M. Di Vito


The relationship between initial population densities of Meloidogyne incognita (Kofoid et White) Chitw. race 1 and growth of susceptible (Yolo Wonder) and resistant (Line 85558) pepper (Capsicum annuum L.) was studied in a glasshouse at 24-28°C. Fortyfive day-old seedlings were transplanted in clay pots containing 600 cm' of steam sterilized sandy soil artificially infested with 0, 0.125; 0.25, 0.5, 1, 2, ... 128 and 256 eggs and juveniles of the nematodes/cm'. Results agree with the equation y=m+(I-m) ZP-T and suggest a tolerance limit of 0.74 eggs and juveniles/cm' soil for both pepper genotypes. Minimum relative yields were 0.1 and 0.4 for «Yolo Wonder» and «Line 85558», respectively. Final population densities of M. incognita increased in pots with low initial densities and planted with the susceptible cultivar, but declined in those with high inoculum levels planted with «Yolo Wonder», and at all initial population densities with «Line 85558».