Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 29, 1996
Publication Date: N/A
Interpretive Summary: A study was conducted to develop a quick and repeatable method of evaluating cantaloupe (Cucumis melo) germplasm for resistance to strain-B of the sweetpotato whitefly (also called silverleaf whitefly). This whitefly sucks on juices of cantaloupe leaves which can weaken and kill the plant. The research was focused on identifying resistance for western-type emelon. Several greenhouse tests were done on plant growth responses to whitefly feeding as well as on plant-selection for egglaying by the whitefly. The young plants were exposed to the whiteflies. Data on plant condition and the number of immature whiteflies on the plants were the best indicators of plant resistance. Other plant data, especially total plant weight, were helpful but were not as constant. The most resistant cantaloupes are the ones which grow well and have few whiteflies. This technique allows for the testing of plants year-round and within a short time, only three weeks after planting.
Technical Abstract: A study was conducted to develop a rapid and reproducible method of screening melon (Cucumis melo L.) germplasm for resistance to Bemisia argentifolii Bellows & Perring. Multiple tests on plant response and limited antixenosis of 31 selected entries were evaluated when exposed to B. argentifolii in an open-choice test. Entries were evaluated in a whitefly-infested greenhouse section as well as in a whitefly-free greenhouse section. Two weeks after emergence, data were collected on: biomass of roots, leaves, and stems; root and stem lengths; leaf area; number of whitefly eggs and nymphs per unit leaf area; and rating of plant condition. Whitefly density and plant vigor data were better indicators of plant resistance; other plant data, notably total biomass, were complementary, but were not as consistent. Entries with high vigor and low whitefly density were regarded as the most resistant and were selected for follow-up testing. This technique allows the testing of germplasm and segregating populations throughout the year rather than in one portion of the year as has been done in the field.