Comparative tolerances of two Cucumis species to salinity, Rhizoctonia solani and Meloidogyne incognita

Abstract

The search for disease resistance in wild types is continuing, in order to introduce resistant genes from wild relatives. In this study, we found that the wild melon Cucumis prophetarum was comparably more tolerant to salinity, the damping-off disease caused by the fungus Rhizoctonia solani and the root-knot nematode Meloidogyne incognita. The percentage of wild melon survival was 60% compared to that of the cultivated cucumber Cucumis sativus, which was 15%, when irrigated with NaCl at a concentration of 2500 ppm; and 96% for the wild melon compared with 44% for the cultivated cucumber when irrigated with CaSO4.2H2O at a concentration of 1000 ppm. Wild melon plants were more tolerant to R. solani attack, as only 20% of the plants were infested compared with 100% of infestation observed for the cultivated cucumber. The average number of nematode galls was 250 per plant on the cultivated cucumber when compared with 6.3 per plant on the wild species. Wild melon could be a potential source of resistant or tolerant genes that can be transferable to cultivated cucumbers.

New pepper accessions proved to be suitable as a genetic resource for use in breeding nematode-resistant rootstocks

“…The gall index was also evaluated following the 0–10 scale developed by Bridge and Page (1980). This parameter is frequently used to evaluate resistance to RKN in pepper (Djian-Caporalino et al , 2014; Ros-Ibáñez et al , 2014) and other horticultural crops (Abu Irmaileh et al , 2013). In addition, in GH-1, the marketable yield of each accession was measured, obtaining the partial yields for three harvest periods – initial (period 1), central (period 2) and final (period 3).…”