Two root-knot nematode-resistant bell pepper cultivars, ‘Charleston Belle’ and ‘Carolina Wonder’ (Capsicum annuum L. var. annuum], and their susceptible parents, ‘Keystone Resistant Giant’ and ‘Yolo Wonder B’, were compared for managing the southern root-knot nematode [Meloidogyne incognita (Chitwood) Kofoid and White] in fall and spring tests at Citra, FL. In the fall test, ‘Charleston Belle’ and ‘Carolina Wonder’ exhibited minimal root galling and nematode reproduction, and ‘Keystone Resistant Giant’ and ‘Yolo Wonder B’ exhibited severe root galling and high nematode reproduction. Fruit yield of ‘Charleston Belle’ was 97% greater than yields of the two susceptible cultivars (P ≤ 0.006). In the spring test, one-half of the plots were treated with methyl bromide/chloropicrin before planting the same four bell pepper cultivars. ‘Keystone Resistant Giant’ and ‘Yolo Wonder B’ grown in untreated control plots exhibited severe root galling and high nematode reproduction, but the other six cultivar × methyl bromide combinations exhibited minimal root galling and nematode reproduction. Although soil temperatures (10-cm depth) were greater than 30 °C on 78 days and 57 days during the Fall 2002 and Spring 2003 trials, respectively, resistance did not break in ‘Charleston Belle’ and ‘Carolina Wonder’ in either test. These results demonstrate that root-knot nematode-resistant cultivars such as Charleston Belle and Carolina Wonder are viable alternatives to methyl bromide for managing southern root-knot nematode in bell pepper in sub-tropical environments.
Judy A. Thies, Don W. Dickson and Richard L. Fery
Andrew P. Nyczepir, Janete A. Brito, Don W. Dickson and Thomas G. Beckman
Six commonly known peach rootstocks (i.e., Flordaguard, Guardian®, Halford, Lovell, Nemaguard, and Okinawa) were evaluated for their susceptibility to Meloidogyne mayaguensis in the greenhouse. All rootstocks were rated as either nonhosts (highly resistant) or poor hosts (resistant) of M. mayaguensis. Lovell generally supported greater numbers of M. mayaguensis eggs per plant and eggs per gram of dry root, whereas no nematode reproduction was noted on Flordaguard rootstock (nonhost). Root galling occurred on all six rootstocks. However, reproduction as measured by number of egg masses, eggs per plant, and eggs per gram of dry root was a better measure of host resistance than number of root galls per plant.