Reaction of Different Pepper Cultivars to Two Species of Root- Knot Nematodes (M. Javanica and M. Incognita)

Root knot nematode is one of the important plant pathogens that causes damage to many crops, including greenhouse crops. Pepper is an agricultural crop which its cultivation has increased in recent years, especially in greenhouses. Most of the adopted management methods for this nematode have not met the required efficiency. In this study, reaction of some pepper cultivars (Elmina, Tuvana, Chaliston, Sera Demre8, hybrid Aristotle, the California Wonder, Dymaz and Green chilli) to the presence or absence of two root-knot nematodes (M. javanica and M. incognita) was investigated. The nematode was isolated from infested root samples collected from Isfahan and Saveh greenhouses and was identified by the morphometric and morphological characteristics. Nematodes were reared on tomato. The seeds of pepper cultivars were sown in seedling trays and the seedlings with similar growth were transferred to the main pots (having diameter of 15 cm) containing 2 kg of sterilized soil (1:1:1 field soil, sand and manure). At the 4-leaf stage, they were inoculated with 2500 eggs and larvae per kg soil. The experiment was carried out as a factorial based on completely randomized design with four replications. Four months after nematode inoculation, results were evaluated using plants’ growth indices (fresh and dry weight of roots and shoots, length of roots and height of shoots) and growth and developmental factors of nematodes (number of moths per g of root, number of egg colonies per g of roots, number of eggs per colony of eggs, and population of second age larvae per 200 g soil). The Chaliston, California Wonder, hybrid Aristotle and Tuvana cultivars showed low sensitivity to M. javanica nematode, compared to other cultivars. The growth and developmental indices of nematodes in different cultivars showed significant difference. Therefore, based on the Canto-Saenz system, they were divided into two groups of sensitive and resistant cultivars. But all the cultivars were susceptible to M. incognita nematode, except California Wonder cultivar.