Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/16/2008
Publication Date: 6/1/2008
Citation: Rashid, T., Muhammad, A., Abel, C.A., Adams, L.C. 2008. Monitoring insects in sweetpotatoes with sweep net and sticky traps across the Mississippi Delta: a omparative study. HortScience. 43(3):601-630.
Interpretive Summary: Sweetpotato is an important food crop with approximately 38,700 ha grown in the United States. Sweet potato production is increasing in the Mississippi Delta region where the majority of the crop is grown by small-acreage, low-income farmers. This region is a fertile, flat, alluvial plane that has primarily been used for intense cotton production since the early 19th century. Because sweetpotato production in this area is relatively new, little is known about the most common pests of the crop and how to sample them. In 2007, we monitored insect populations in sweetpotato fields in the Mississippi Delta by using different sampling methods. Sticky traps collected three species of click beetles (also known as wireworms) several species of tortoise and flea beetles, bean leaf beetle, and spotted cucumber beetle (also known as the southern corn rootworm). Significantly more click beetles were collected during August than in mid September. Sweep net sampling collected all of the above species with the exception of bean leaf beetle. However, click beetles and flea beetles were only collected using the sweep net method during the period of 2 July to 6 August. Significantly more click beetles and tarnished plant bugs were collected in purple sticky traps, whereas, the numbers of tortoise beetles sampled from yellow sticky traps was higher. The numbers of spotted cucumber beetle collected on 17 and 29 August in purple sticky traps were significantly higher. Overall, the purple stick traps may provide a useful alternative to using the sweep net for sampling pests of Mississippi Delta grown sweetpotato.
Technical Abstract: Insect populations in sweetpotato fields in the Mississippi Delta were monitored in 2007 by comparing traditional sweep net sampling with purple and yellow sticky traps. Four sweep net samples each consisting of 25 sweeps were taken weekly from each of four different locations from 2 July to 3 September. On 31 July, eight replications of each purple sticky and Pherocon AM yellow sticky traps were installed at each of three locations. The traps were checked on 9, 17, 29 August and 14 September. Insect samples were collected and identified. Three species of click beetles (adult wireworms, mostly Conoderus vespertinus), Cerotoma trifurcata, Lygus lineolaris, Diabrotica undecimpunctata, and several species of tortoise and flea beetles were collected in purple/yellow sticky traps or sweep net samples. Significantly (P<0.001) more click beetles were collected in purple traps during August than in mid September. Purple traps installed along private farmers’ fields collected more click beetles than did traps along research field plots. Consistent numbers of other insect species were collected in both purple and yellow traps. Sweep net sampling collected all insect species except C. trifurcata, whereas, click beetles and flea beetles were only collected during the period of 2 July to 6 August. Significantly (P<0.001) more click beetles and L. lineolaris were collected in purple sticky traps, whereas, the numbers of tortoise beetles trapped in yellow sticky traps were significantly (P<0.001) higher than those in purple traps. The numbers of D. undecimpunctata collected on 17 and 29 August in purple sticky traps were significantly (P<0.001) higher. Purple sticky traps may provide a viable alternate method to sweep net sampling for insect pests of sweetpotatoes in Mississippi.