Resistance and Tolerance of Commercial Onion Cultivars to Stem and Bulb Nematode, Ditylenchus dipsaci

Abstract

Nematode resistance and tolerance reactions of 28 onion cultivars grown commercially in Turkey to stem and bulb nematode were studied at 20 °C, 70% RH and 16:8 h L:D photoperiod in growth chamber with 10 replications and at 27±4 °C and 16:8 h L:D photoperiod in greenhouse with 3 replications, respectively. Ditylenchus dipsaci multiplied in all cultivars tested. The lowest multiplication was determined in cv. Valenciana from Atatürk Horticultural Central Research Institute with 91 nematodes/pot and a multiplication rate of 0.5. Plant height of cultivars were significantly different in the first tolerance experiment with having an average plant hight of 33.5 and 103.1 mm for inoculated and inoculated plants, respectively (P