Effects of using chemical-free root-knot nematode (Meloidogyne incognita) control methods on the occurrence of blossom-end rot in pepper

Pepper takes up the largest growing area among forced vegetables in Hungary. The most significant abiotic disease problem of this plant is blossom-end rot (BER), which can cause substantial yield losses. The uptake of calcium by plants from the soil may be negatively affected by many factors such as root-knot nematodes feeding on the roots. The nematodes then impede water and nutrient transport. In Hungary, Meloidogyne incognita is the most common root-knot nematode species in greenhouses. The use of resistant cultivars is undoubtedly the most successful control method of root-knot nematodes in warm climates. Growing of resistant pepper cultivars, and grafting onto resistant rootstocks offer alternative, environmentally friendly ways of control. The main objective of this study was to investigate the effect of both growing resistant pepper cultivars and using resistant rootstocks on the occurrence of fruit showing symptoms of BER. Research was carried out in a plastic tunnel with soil which was heavily infested with M. incognita. Roots of the non-resistant cultivars were moderately damaged by the pest at the end of the vegetation period. After grafting these cultivars onto two different resistant rootstocks, symptoms of damage caused by M. incognita were not observed on the rootstocks. There was a negligible number of galls appearing on the roots of the resistant cultivar Cinema F1. Due to the resistance properties and other characteristics of the newly bred Cinema F1, fruit of this cultivar rarely show symptoms of calcium deficiency. In most cases, there was less fruit with BER symptoms in plants grafted onto rootstocks Robusto F1 or Snooker F1. The results showed a reduction in the extent of damage caused by the root-knot nematode, and there were other beneficial effects of the rootstocks on the scions. The occurrence of fruit showing symptoms of BER was reduced.