INSECTICIDE RESISTANCE MANAGEMENT AND NEW CONTROL STRATEGIES FOR PESTS OF CORN, COTTON, SORGHUM, SOYBEAN, AND SWEET POTATO
Location: Southern Insect Management Research Unit
Title: Insect infestations crop development and evolving management approaches on a northeast Arkansas cotton farm
Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Abstract Only
Publication Acceptance Date: January 31, 2011
Publication Date: May 1, 2011
Citation: Luttrell, R.G., Allen, K.C., O'Leary, P., Teague, T.G. 2011. Insect infestations crop development and evolving management approaches on a northeast Arkansas cotton farm. National Cotton Council Beltwide Cotton Conference. p.1185. In. Proc. Beltwide Cotton Conf., Memphis, TN.
Interpretive Summary: On-farm databases for COTMAN information, crop production records and insect scouting information were organized and studied for Wildy Farms in Mississippi County, Arkansas for the years 1997 through 2007. A dramatic increase in yield of ~ 60 lbs of lint per acre per year was evident in the data and closely associated with the adoption of new Bt cotton varieties and reduced conventional tillage. It is noteworthy that similar yield increases were observed on non Bt cotton varieties on the farm. It is also noteworthy that a corresponding increase in yields was not observed for similar varieties on a nearby University of Arkansas Experiment Station. Yield on the University of Arkansas Experiment Station was significantly higher than that of Wildy Farms early in the study, but less than that of the production fields on Wildy Farms late in the study. The information summarized provides important temporal benchmarks for management decisions and the threat of pest damage that may be used to further sophisticate management strategies on the farm. Wider adoption of this type of management information that links crop development and risk of insect injury would enhance efficiency of new production technologies.
COTMAN information, cotton production records and insect scouting reports for Wildy Farms in Mississippi County, Arkansas were organized into large databases and studied for variability among years and fields in a wide range of crop and insect indices. The study included records from 126 individual production fields over an 11-year period from 1997-2007. This information is potentially important as a historical benchmark because it transcends the introduction of Bt cotton varieties and the start and finish of active Boll Weevil Eradication. The high level of crop management information used routinely on the farm is also a model system worthy of study and duplication.
Yield increased at a rate of ~ 60 lbs of lint per acre per year over the 11-year period. The increase in yield was highly correlated with increased adoption of Bt cotton and reduced intensity of conventional tillage. A corresponding yield increase among similar varieties was not observed on a nearby University of Arkansas Experiment Station. Average within-year Julian dates (calendar dates) for major production events were: planting – 123 (May 2), defoliation – 259 (September 15), application of boll opener – 264 (September 20), 1st harvest – 279 (October 5), 1st foliar spray – 133 (May 12), 1st heliothine spray – 213 (July 31), 1st plant bug spray – 174 (June 22), 3rd square – 169 (June 17), 5th square – 176 (June 24), 7th square – 181 (July 2), NAWF 5 – 215 (August 2), 1st detection of plant bugs – 170 (June 18), 1st detection of heliothine larvae – 208 (July 26), last date of plant bug detection – 206 (July 24), and last date of heliothine larvae detection – 223 (August 10). Over the 11 years, DD60s to 1st foliar spray decreased at a rate of 56.8 DD60s per year, DD60s to last foliar spray decreased at a rate of 36.5 DD60s per year, number of heliothine sprays decreased at a rate 0.11 sprays per year, number of plant bug sprays increased at a rate of 0.18 sprays per year, and number of cutworm sprays increased at a rate of 0.11 sprays per year. Bt fields had more DD60s at planting, more DD60s from planting to 1st heliothine spray, fewer helitohine sprays and fewer heliothine larvae per row foot than non Bt fields. Conventional tillage fields had higher square shed rates at 3rd square, more weevil damaged squares per row foot, more heliothine eggs, larvae and worm damage than non-conventional tillage fields.
Overall observations indicated that increased yields were observed in both Bt and non Bt cotton varieties over the study period. Reduced conventional tillage also contributed to the higher yields. Information from the study on timing and intensity of crop and insect management events allowed Wildy Farms to optimize production and more efficiently manage insects and the timing of cotton crop set. Adoption of higher level management systems, like COTMAN and routine crop management record keeping, would likely benefit other growers and stimulate more efficient use of new cotton varieties and farming technologies.