Seasonal fluctuation and biological control of root- knot nematodes Meloidogyne incognita on cucumber

The experiments were conducted under both greenhouse and field conditions to determine seasonal fluctuation and application of some bioagents to control root-knot nematode Meloidogyne incognita on cucumber. Seasonal fluctuation of the root-knot nematode M. incognita was studied on two cucumber cultivars (Madia and Slaprty) during the period from March to November in seasons 2015/2016 and 2016/2017. Soil population increased gradually on two cultivars during spring and throughout summer to reach peak in August began to decrease during autumn and reach the lowest in winter (January and February) in two seasons where soil temperature reached 15± 4ºC. Seven treatments Paecilomyces lilacinus, Arthrobotrys oligospora, Glomus faciculatum, Eucalyptus globules, Tagetes erecta, Allium sativum and Fenamiphos (10%G) were evaluated to control M. incognita. All the treatments decreased the nematode population of M. incognita in soil and on roots compared with check. Data indicated percent increase of fresh weight of the whole plant which was greatly improved in all treatments.