02043nas a2200229   4500008004100000245016000041210006900201260001200270300000800282490000600290520120100296653002801497653001701525653002501542653001201567653001301579653002101592653002401613653001401637100003101651856013101682       1997                        eng d00aObservations on the variability in reproduction of some populations of root-knot nematodes (<i>Meloidogyne </i>spp.) on resistant tomatoes in Crete, Greece0 aObservations on the variability in reproduction of some populati  c1997///  a1-60 v53 aExperiments under controlled conditions with a few naturally occurring populations and single egg mass lines of root-knot nematodes (Meloidogyne spp.) from Crete demonstrated the nematodes ability to produce low numbers of egg masses on several resistant tomato cultivars. Except for one naturally virulent population of M. javanica, reproduction on resistant cultivars was significantly lower than on a susceptible cultivar. A quantitative nature of the Mi resistance gene was revealed by the differential reproduction of a partially virulent line of M. javanica on heterozygous and homozygous resistant tomatoes. Virulent clones were not produced from a few single egg mass lines of Meloidogyne spp. on a resistant cultivar during a two generation period. Only one line produced two egg masses for two generations but the evidence is probably insufficient to prove a genetic inheritance of virulence. At high soil temperature (>28°C) resistance was probably decreased and a non-virulent population reproduced on a resistant cultivar. The requirements for further research and practical recommendations for successful implementation of resistant tomatoes in management strategies are discussed.10aLycopersicon esculentum10aM. Incognita10aMeloidogyne javanica10aMi gene10aNematoda10aPlant resistance10aRoot-knot nematodes10aVirulence1 aTzortzakakis, Emmanuel, A.  uhttps://icgf.myspecies.info/content/observations-variability-reproduction-some-populations-root-knot-nematodes-meloidogyne-spp