Host suitability of pepper cultivars to Nacobbus aberrans populations from Argentina.

LAX, P.; DOUCET, M.E; BRAGA, R.; KOBORI, R.

Congreso; Second International Congress of Tropical Nematology; 2009

In several localities of the American continent, N. aberrans produces severe damage to pepper crops in field and greenhouses. Host suitability of three pepper cultivars (carrying genes resistant to Meloidogyne spp.) to N. aberrans populations from Argentina was evaluated. The nematodes were from the localities of Río Cuarto (RC) and Lisandro Olmos (LO), Córdoba and Buenos Aires, respectively. The cultivars considered were: AF 8724, AF 8765 (both carrying the Me 1 gene) and AF 2739 (carrying the Me 7 gene); tomato Platense, which is susceptible to the nematode species, was used as control. The experiment was conducted in greenhouse conditions at a mean temperature of 25 °C; six replications per cultivar were performed. Each plant was inoculated with 100 second-stage juveniles at planting. The nematode Reproduction Factor (RF=final density/initial density) was estimated 100 days after inoculation. Both populations reproduced abundantly on all pepper cultivars (RF ranging between: 25.1-30.4 for RC and 22.8-36.9 for LO). In the case of LO population, AF 8765 and AF 2739 yielded RF values higher than those obtained for tomato. No significant differences between populations were observed in the different cultivars analyzed (including the control one) or between cultivars for a single nematode population. The genes Me 1 and Me 7 did not confer resistance to infection by the nematode populations considered. Because N. aberrans is polyphagous and has high reproductive potential, encouraging research aimed at selecting resistant cultivars is of great importance.