Sources of whitefly (Homoptera: Aleyrodidae) resistance in Citrullus for the improvement of cultivated watermelon

Abstract

The B-biotype sweetpotato whitefly, Bemisia tabaci (Gennadius), feeds on and damages numerous vegetable crops including watermelon (Citrullus sp.). Seven watermelon cultivars, a triploid line, and 16 U.S. Plant Introduction accessions (PIs) of C. lanatus var. lanatus; 10 PIs of C. lanatus var. citroides; and eight PIs of C. colocynthis, were evaluated for resistance to B. tabaci. Bioassays were based on nonpreference and performance of the whiteflies on the 42 Citrullus genotypes. Most of the watermelon cultivars and C. lanatus PIs tested were highly susceptible to whitefly infestation, while the C. colocynthis accessions exhibited whitefly resistance. Among the C. colocynthis accessions tested, PI 386015, PI 386018, and PI 386024 were most resistant to B. tabaci. This study identified useful sources of germplasm that can be used for the improvement of watermelon for resistance to whiteflies.