Acessibilidade / Reportar erro

Potential of wild Solanum stramonifolium accesses as rootstock resistant to soilborne pathogens in tomato crops

Potencial de acessos selvagens de Solanum stramonifolium como porta enxertos resistentes para patógenos de solo em cultivos de tomate no Brasil

ABSTRACT

Resistant rootstocks is one of the most effective method to control soilborne pathogens in tomato crops. Thus, this study was installed to evaluate the reaction of Solanum stramonifolium accesses to Fusarium oxysporum f. sp. lycopersici (Fol) races 2 and 3 and to Meloidogyne enterolobii (Me). The seedlings were grown in trays and inoculated separately with Fol races 2 and 3 at 50 days after planting by immersing the roots in the spore suspension (1×106 microconidia mL-1). Then, seedlings were transplanted in pots containing sterilized soil and kept in greenhouse conditions. To study the reaction of S. stramonifolium accesses to nematodes, we used 27-day old seedlings that were also planted in pots and inoculated with 6,000 eggs and second-stage juveniles in greenhouse conditions. The experiments were evaluated in the 34th day (Fol) and in the 64th day (Me) after inoculation. The experiment consisted of a randomized block design with five replications, where each plot consisted of one pot with three plants (Fol) and one pot with one plant (Me). We observed that the plants used as controls, susceptible to Fol races 2 and 3 and Me, presented 100% of incidence. All accesses were resistant to Fol race 2 and the accesses CNPH-19, CNPH-22, CNPH-23, CNPH-25, CNPH-120, CNPH-122 and CNPH-349 presented multiple resistance to pathogens, indicating great potential for using as resistant rootstock. The CNPH-24, CNPH-119, CNPH-121 and CNPH-336 accesses also presented resistance to nematode. However, they presented slight browning symptoms of vascular tissues when they were inoculated with Fol race 3. This symptom was also observed in the CNPH-21, CNPH-107 and CNPH-117 accesses. All other accesses were resistance to Fol race 3 and susceptible to Me.

Keywords:
Meloidogyne enterolobii; Solanum lycopersici; fusarium wilt; grafting; genetic resistance

Associação Brasileira de Horticultura Embrapa Hortaliças, C. Postal 218, 70275-970 Brasília-DF, Tel. (61) 3385 9099, Tel. (81) 3320 6064, www.abhorticultura.com.br - Vitoria da Conquista - BA - Brazil
E-mail: associacaohorticultura@gmail.com