Sampling strategies for square and boll-feeding plant bugs (Hemiptera: Miridae) occurring on cotton.
Sampling methods for square and boll-feeding plant bugs (Hemiptera: Miridae) occurring on cotton, Gossypium hirsutum L., were compared with the intent to assess if one approach was viable for two species occurring from early-season squaring to late bloom in 25 fields located along the coastal cotton growing region of south Texas. Cotton fleaphopper, Pseudatomoscelis seriatus (Reuter), damages squares early-season and dominated collections using five sampling methods (approximately 99% of insects collected). A major species composition shift occurred beginning at peak bloom in coastal fields, when verde plant bug, Creontiades signatus Distant, represented 55-65% of collections. Significantly more cotton fleahoppers were captured by experienced samplers with the beat bucket and sweep net than with the other methods (30-100% more). There were more than twice as many verde plant bugs captured by experienced and inexperienced samplers with the beat bucket and sweep net than captured with the KISS and visual methods. Using a beat bucket or sweep net reduced sampling time compared with the visual method for the experienced samplers. For both species, comparing regressions of beat bucket-based counts to counts from the traditional visual method across nine cultivar and water regime combinations resulted in only one combination differing from the rest, suggesting broad applicability and ability to translate established visual-based economic thresholds to beat bucket-based thresholds. In a first look at sample size considerations, 40 plants (four 10-plant samples) per field site was no more variable than variation associated with larger sample sizes. Overall, the beat bucket is much more effective in sampling for cotton fleahopper and verde plant bug than the traditional visual method, it is more suited to cotton fleahopper sampling early-season when plants are small, it transitions well to sample for verde plant bug during bloom, and it performs well under a variety of soil moisture conditions and cultivar selections.
Texas AgriLife Research and Department of Entomology, Texas AgriLife Research and Extension Center at Corpus Christi, 10345 State Hwy. 44, Corpus Christi, TX 78406, USA. mjbrewer@ag.tamu.edu
Michael J
MJ
Brewer
Darwin J
DJ
Anderson
J Scott
JS
Armstrong
Raul T
RT
Villanueva
D000818:Animals; D003368:Gossypium / Q000254:growth & development / Q000469:parasitology*; D006430:Hemiptera; D007300:Insect Control / Q000191:economics; D009758:Nymph; D018401:Sample Size