Resistance of local okra cultivars against Meloidogyne incognita (Kofoid & White, 1919) (Nematoda: Meloidogynidae), effects of nematode infestation on growth parameters and leaf macro- micronutrients

Okra is an important species of vegetable grown in Turkey and around the world. Root-knot nematodes cause serious yield losses in vegetables. Twenty-six cultivars okra were obtained from the Aegean Agricultural Research Institute in 2002. Resistance of this cultivars to nematode was determined and changes induced with nematode infestation on plant morphology and macro- and micronutrients in leaves measured. The experiments were conducted in completely randomized design with four replicates in climate-controlled glasshouse at Alata Horticultural Research Institute in 2019. The cultivars were tested against Meloidogyne incognita (Kofoid & White, 1919) (Nematoda: Meloidogynidae) at 25 +/- 2 degrees C. Sixty days after inoculation, root gall indexes varied with an average of 4.56. Compared to uninoculated controls, nematode inoculated reduced plant height by 46.0%, stem thickness by 9.06%, root lengths by 39.7%, leaf widths by 15.1%, leaf lengths by 20.5% and increase root weight by 14.5%. Leaf macro- and micronutrients were determined. Compared to the control, nematode inoculation reduced leaf N, P, K and Mg concentrations by 2.31, 5.85, 5.24 and 10.3%, respectively, and increased Ca, Fe, Zn, Mn and Cu concentrations by 7.91, 17.0, 13.4, 118 and 15.6%, respectively.