Evaluation of hot pink traps to monitor pests on ornamental crops
Robb KL1, Newman J2, Costa HS3, Parker S4
1University of California Cooperative Extension, 5009 Fairgrounds Rd, Mariposa, California, USA
2University of California Cooperative Extension, Counties of Ventura and Santa Barbara, USA
3Department of Entomology, University of California, Riverside, California, USA.
4University of California Cooperative Extension, County of San Diego, California, USA
Correspondence: heather.costa@ucr.edu
Industry standards for ornamental crops are blue or yellow sticky traps for thrips (Heinz et al. 1992, Journal of Economic Entomology 85:2263¨C2269). Tsuchiya et al. (1995, Japanese Journal of Applied Entomology and Zoology 39:313¨C319) demonstrated a significant preference by western flower thrips for hot pink in mandarin oranges. If pink proved significantly more attractive to western flower thrips in flower crops, we would consider changing the color of the petunia tospovirus indicator plant stands (Robb et al. 1999. http://comserv.ucdavis.edu/CESanDiego) to pink to increase the attractancy of the indicator plants. We were also interested in determining whether there would be an advantage to switching from yellow sticky traps to pink. Trials were conducted to verify color preference by western flower thrips and other insects in San Diego County and Ventura County. Blue, yellow and hot pink traps were created and placed in a field grown cut chrysanthemum crop. In each trial, 10 traps of each color were evaluated in a randomized design. The trial was replicated five times over 5 weeks. Greenhouse trials were conducted amongst a crop of impatiens bedding plants that were just beginning to show color. Although western flower thrips were the target pest, numbers of leafminers, whiteflies, aphids and fungus gnats captured were also recorded. All data were analyzed using ANOVA. Hot pink was not preferred by western flower thrips over blue. The number of western flower thrips on hot pink was not statistically different than the number caught on yellow sticky traps. Moreover, pink traps were no more attractive than yellow to aphids, leafminers, whiteflies or fungus gnats. As a result of these findings, we do not recommend changing the color of the petunia indicator plant stands used for detecting tospovirus infective thrips from blue to pink. There is also no advantage to using hot pink sticky traps for the other ornamental plant insects monitored in this trial, so no modifications to existing trap strategies are recommended.
