Root-knot nematode control investigations in tobacco in Queensland

Abstract

During 1948-55, 8 field trials were set out in North Queensland to investigate the control of the root-knot nematode Meloidogyne javanica (Treub) Chitwood, which is a serious pest of tobacco. It is shown that, irrespective of the use of nematocides in the field, even a trace of nematode galling in seedlings can be primarily responsible for appreciable economic losses. In heavily infested irrigated fields, yields and appraised values can be increased more than threefold by the correct use of either DD or EDB. Where tobacco is grown each year on the same site, galling tends to increase at a greater rate than where resistant crops are used in the rotation. This use of resistant crops, however, does not prevent consistently an increase in galling: one of the reasons may be the impracticability of obtaining pure stands of resistant plants.