Host-parasite Interactions between Solanum aethiopicum, Meloidogyne incognita, and Fusarium oxysporum f.sp. melongenae as Portrayed by Disease Traits and Crop Yield

Abstract

Solanum aethiopicum L. cultivation is highly constrained by wilt disease induced by Fusarium oxysporum f.sp melongenae and Meloidogyne incognita. The effects of initial population densities of these pathogens on the crop were investigated to enhance knowledge of the host-parasite interactions. The 4 x 4 factorial set of treatments were laid out in the field using the randomized complete block design with three replications. Data were collected on plant vigour, vascular discoloration, fruit weight, shoot weight, root-gall index, final nematode population, disease incidence, and disease severity. The different initial population densities of Fusarium and/or Meloidogyne spp. had detrimental effects on the crop compared to the Control. The main effects of the pathogens on the crop/wilt showed the existence of cross-over interactions for all the disease parameters. The effects of the pathogens on yield (fruit weight and shoot weight) were partially directly proportional to population densities even though the effects were significantly different (P≤0.05) compared to the Control. All the disease parameters were positively correlated. Each of the pathogens was capable of causing severe damage to the crop in either single or concomitant infection.