Canola quality oil produced from oilseed rape, Brassica napus L. (Brassicaceae), is a relatively new crop in the United States and is damaged by a number of insect pests, including the crucifer specialist diamondback moth, Plutella xylostella (L.). Greenhouse tests were performed to evaluate resistance in normal-leafed ('Bingo', 'Cobra', 'Oscar') and glossy-leafed B. napus plants ('glossy Bingo' and plant introductions (PI) 469895, 470055, 470055-2, and 470064) to identify potential resistant sources to diamondback moth. Normal-leafed PI 171538, originally described as B.napus and recently reclassified as B.oleracea, also was evaluated for resistance with B.napus plants and B. oleracea cultivars of broccoli, 'Green Comet', 'Green Valiant', and collard 'Vates'. Plants of Cornell 92-8611, a broccoli with glossy-leaf type (glossy broccoli), were used as the resistant control in all trials. B. napus entries failed to show feeding nonpreference or antibiosis comparable to that of glossy broccoli. Furthermore, no significant differences were detected between normal and glossy-leafed B. napus lines for most of the parameters tested. Within the tested B. napus entries, PI 470055 exhibited low levels of feeding damage in the restricted-feeding test and some level of antibiosis against diamondback moth. However, B. oleracea entry PI 171538 showed a greater or comparable level of resistance to that of glossy broccoli. Nonpreference for larval feeding and adult oviposition were exhibited by PI 171538. In feeding tests, PI 171538 was less defoliated compared with other B. o/eracea entries. Diamondback moth larvae reared on PI 171538 leaves for 5 d had a lower head capsule width compared with larvae reared on other entries. In an oviposition preference test, PI 171538 received 0.9% of eggs as compared with normal-leafed B. napus plants (2.1-4.4%) and glossy broccoli, which received 7.0% of eggs. The experiments indicate that the normal-leafed B. a/eracea entry PI 171538 has considerable resistance against diamondback moth. PI 171538 is a newly discovered source of resistance and has leaf characteristics that differ from the previously reported diamondback moth-resistant B. oleracea lines.
Document Type: Research Article
Publication date: August 1, 1998
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.