Reproduction of Root-Knot Nematode Isolates from the Middle Black Sea Region of Turkey on Tomato with Mi-1.2 Resistance Gene

Abstract

Research was conducted to evaluate the reproduction of 90 Meloidogyne isolates including Meloidogyne arenaria (Neal, 1889) Chitwood, 1949 (38 isolates), Meloidogyne incognita (Kofoid and White, 1919) Chitwood, 1949 (4 isolates), Meloidogyne javanica (Treub, 1885) Chitwood, 1949 (11 isolates) and Meloidogyne luci Carneiro et al., 2014 (37 isolates) (Tylenchida: Meloidogynidae) from the middle Black Sea Region of Turkey on susceptible and resistant tomato cultivars in a greenhouse with temperature controlled between 2013 and 2014. Galling index and reproduction factor of nematode isolates were assessed in a pot assay and resistance-breaking isolates were determined according to their reproduction index. Among the isolates, only two isolates of M. luci (Or-2 and Pr-1) had a similar galling index on susceptible and resistant tomato (P 0.05). Four isolates of M. luci (Cr-19, Or-2, Pr-1 and Pr-2), two isolates of M. arenaria (A-7 and Sn-11) and an isolate of M. incognita (A-11) produced more eggs than the initial inoculum on resistant tomato. These root-knot nematode isolates, except two isolates of M. arenaria, were classified as resistance-breaking isolates having a reproduction index higher than 10%. These findings showed that the Mi-1.2 gene confers resistance to M. luci but four isolates of M. luci could overcome this resistance. This is the first report for resistance-breaking isolates of M. luci in tomato. © 2019 Entomological Society of Turkey. All rights reserved.