Evaluation of common pepper cultivars in Iran for resistance to root-knot nematode (Meloidogyne incognita race-2) in greenhouse conditions

Root-knot nematodes (Meloidogyne spp.) are the limiting factors of agriculture crops including pepper. The M. incognita has widely distributed in pepper fields of Gilan Province. In this study, eleven pepper cultivars including AA pepper (Hyb. Coyame- Petoseed, Hyb. Aziz- Petoseed, Hyb. Bounty- Petoseed) and Bell peppers (California Wonder 301- Petoseed, Hyb. Camelot- Petoseed, Hyb. King Arthur- Petoseed, Hyb. Wizard- Petoseed, Hyb. Aristotle (SQ-R)- Petoseed, Hyb. Plato (SQ-R)- Petoseed, Mercury- Petoseed, California Wonder 301- Canyon) were evaluated against M. incognita race 2. Experiments conducted in a completely randomized design with four replications in greenhouse conditions with range of 22 to 28 Celsius degrees. Seedlings with six leaves were inoculated with 2000 second-stage juveniles/kg soils. Eight weeks after inoculation, growth indexes cultivars (Chlorophyll content of leaves, fresh and dry weight of shoot and root, root length and volume, length and diameter of shoot and number of healthy leaves) and nematode reproductive traits (Number of galls, egg masses, juveniles in the soil and nematode reproduction factor) were evaluated. In the final reaction of cultivars were determined based on reproduction factor gall and egg masses and resistance indices. The results revealed that pepper cultivars showed different ranges of sensitivity to the nematode. Based on the growth factors, hybrid wizard, California Wonder 301, Bavnty Hybrid, Mercury and Camelot hybrid cultivars were less sensitive than others cultivars. Among cultivars, California Wonder 301, Bavnty Hybrid, Mercury and Camelot hybrid showed less sensitivity in reproductive. The assessment of gall, egg masses and resistance indices revealed that Mercury and Camelot hybrid were evaluated as tolerant cultivars and King Arthur's hybrid and aziz hybrids as the most sensitive cultivars.