In vitro susceptibility of root-knot nematode populations (Meloidogyne spp.) from Crete,Greece to oxamyl and fenamiphos

Journal of Plant Diseases and Protection - Carbamate and organophosphate nematicides are routinely used for control of root-knot nematodes (RKN, Meloidogyne spp.) in greenhouses of Crete, Greece....     

Investigation of alternatives to methyl bromide for management of Meloidogyne javanica on greenhouse grown tomato

The root galling index and the densities of eggs in roots and juveniles in soil of the root-knot nematode Meloidogyne javanica (Treub) Chitwood on tomato, and the effect of these on crop yield were assessed in greenhouse experiments applying various treatments at two different sites in Crete, Greece. Tomato crops were grown for four cycles by rotating nematode-resistant (first and third spring crops) with susceptible (second and fourth autumn crops) cultivars and receiving the following treatments: (a) untreated control; (b) methyl bromide application before the first and third crops; (c) application of the fungus Pochonia chlamydosporia (Goddard) Zare, Gams & Evans before planting the first, third and fourth crops with a supplementary application three weeks after the beginning of the fourth crop; (d) application of oxamyl in both sites and fenamiphos in site 1 only at the second and fourth crops; (e) combination of treatments (c) and (d). The fungus density in soil was monitored three weeks after application and at the end of each crop, when roots were lifted. Pochonia chlamydosporia had a variable establishment and did not control the nematode. Its pathogenicity on eggs was not demonstrated, as in all cases galls were big, with all egg masses inside and protected from infection. The methyl bromide treatment significantly reduced root galling and egg production compared to other treatments in all crop cycles and the yield of the fourth crop was significantly greater. Nematicides reduced nematode densities compared with untreated controls and the fungus treatment, but they were less effective than methyl bromide and resulted in increased yield in one site only.     

Detection of the root-knot nematode Meloidogyne ethiopica in Greece

Root-knot nematodes (RKN), Meloidogyne spp., are very significant in agriculture because they can be found almost everywhere and have a wide host range. In summer 2009, two soil samples from maize and kiwi crops, from the area of Kavalla in North Greece, were analyzed for the presence of nematodes. RKN were detected in both samples and identified as M. ethiopica on the basis of biochemical (esterases) and sequence data (18S rDNA). Meloidogyne ethiopica poses a significant threat to farmers in Greece and the establishment and spread of this species has to be controlled. This is the first report of M. ethiopica in Greece and the second report of this species for Europe.     

Selection of virulent Meloidogyne individuals within mixed isolates by continuous cultivation on a Mi gene resistant tomato genotype

Journal of Plant Diseases and Protection - Two isolates of Meloidogyne spp. from two districts (Thrace and Crete) of Greece have been identified as M. arenaria and M. incognita using perineal...     

Integrative diagnosis and molecular phylogeny of dagger and needle nematodes of olives and grapevines in the island of Crete,Greece, with description of Xiphinema cretense n. sp. (Nematoda,Longidoridae)

The occurrence and geographic distribution of longidorid nematode species inhabiting the rhizosphere of cultivated and wild olive and grapevine in Crete Island were investigated. Morphological and morphometrical studies identified five Longidorus and six Xiphinema species, with frequencies of prevalence (for wild and cultivated olives and grapevines, respectively) as follows: Longidorus closelongatus (2.0–13.3 %), L. cretensis (1.0–6.7 %), L. moesicus (13.3 % only in grapevines), L. orientalis (3.3 % only in grapevines), L. pseudoelongatus (7.0 % only in olives), Xiphinema cretense n. sp. (3.0 % only in olives), X. index (3.0–23.3 %), X. israeliae (6.3 % only in olives), X. italiae (3.3–10.0 %), X. pachtaicum (26.7–42 %) and X. simile (3.3 % only in grapevines). Xiphinema cretense n. sp. is characterized by a body size 3,872–6,135 μm long, lip region anteriorly rounded, separated from the rest of the body by a depression, odontostyle and odontophore 140.6 and 80.3 μm long respectively, vulva position at 46.0–50.5 %, female tail 31.0–38.0 μm long, nearly hemispherical with curvature essentially dorsal and with a tip completely rounded or presenting a very short bulge, c ratio (119.1–186.9), c’ ratio (0.7–0.8). Molecular characterisation using D2-D3 expansion regions of 28S rRNA, 18S rRNA and ITS1-rRNA was carried out and maximum likelihood and Bayesian inference analysis were used to reconstruct phylogenetic relationships among these species and with other longidorids.     

Occurrence of a new resistant breaking pathotype of Meloidogyne incognita on tomato in Greece

Journal of Plant Diseases and Protection - In a pot assay, a population of Meloidogyne incognita from Northern Greece, reproduced on the resistant tomato cv. Silvana carrying the Mi gene and on...     

Differentiation in two populations of Meloidogyne incognita from Greece in relation to reproduction on resistant tomato and pepper

Journal of Plant Diseases and Protection - The reproduction of two Meloidogyne incognita populations from Crete, Greece was assessed on ten pepper cultivars in pots in controlled conditions. One...