Final Report for GS12-109
Several agricultural trials have documented the propensity for cotton to overcompensate for fleahopper herbivory (Sansone 2009, Chen et al. 2007 Parker and Buehring 2006, Ring et all 1994). The strongest evidence of overcompensation, however, comes from a field cage study (Ring et al. 1993). Here, we invested how the timing of herbivory influences cotton's overcompensatory response. In a 2011 open-plot field study we found evidence for overcompensation following fleahopper herbivory in the second week of squaring. In this study we used large field cages to replicate the experiment.
Our objective was to investigate how the timing of cotton fleahopper herbivory during cotton squaring influences cotton's overcompensatory response.
This experiment was a 4x2 factorial design with timing of herbivory (1st-4th week of squaring) and fleahopper present or absent as factors.
Twenty 6 feet by 6 feet field cages were erected at the Texas A&M Field laboratory in Burleson Co. Tx. Each cage served as a block and contained 8 transplanted cotton plants assigned to one of the treatment combinations. One adult fleahopper was caged to terminal of the of the cotton plant for 48hours and then removed. Control plants were also treated with empty cages. Sqaureman and Bollman data was collected throughout the summer to track cotton growth following herbivory. Lint was hand-harvested in October.
Lint was harvested in October and is currently being processed to determine if overcompensation occurred (updated October 24th 2013).
Educational & Outreach Activities
Previous findings in the open-plot study were reported in 2012 Cotton Beltwide Proceedings.
Understanding how and when cotton may overcompensate for fleahopper herbivory will aide IPM practitioners to re-evaluate economic threshold levels and maintain maximum yields.