|Mitchell, Forrest - TEXAS AG. EXPT. STATION|
Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: March 3, 2003
Publication Date: October 1, 2003
Citation: Davis, A.R., Pair, S.D., Mitchell, F. 2003. Field screening of citrullus lanatus germplasm accessions for resistance to cucurbit insect pests [abstract]. HortScience. 36(6):1286. Technical Abstract: Squash bug, cucumber beetles, and aphids are important pests of watermelon (Citrullus lanatus) in most production areas of Oklahoma and Texas. In addition, squash bug has been identified as a vector of Cucurbit Yellow Vine (CYVD), a new and devastating disease of cucurbits in the South Central Region for over 10 years. Finding host plant resistance to these pests is important in order to keep watermelon production economically feasible in this region. To this end we screened germplasm for resistance to multiple insect pests and CYVD. We report here preliminary results from two years field trials at Lane, OK. Forty-six PI lines were assessed in 2001, and 9 PI lines were reevaluated in 2002 using weekly insect counts and biweekly disease ratings. The term resistance is used here for PI lines that had no or very little insect colonization and exhibited no CYVD in both years. We found potential resistance to squash bugs in PI lines 459074, 254737, 270565, 494527, and 494815 and to cucumber beetle (striped and spotted) in PI lines 459074, 299563, 248178, and 560000. Potential resistance to aphids (winged and non-winged) was seen in PI lines 185635, 494527, and 500327. PI line 270565 showed the highest potential resistance to CYVD in our two-year trial. A weak correlation was detected between squash bug colonization and CYVD incidence but not to cucumber beetle or aphid colonization. Further greenhouse and field trials are required to verify the field results.