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Bollworms develop on many hosts, with each generation likely to use a different host. Pyrethroid insecticides are typically used to control bollworms in cotton as well as in numerous other crops that are attacked by this insect. Therefore, selection for pyrethroid resistance within the landscape is potentially great even though there may not be much selection pressure in any single environment. Pheromone traps were monitored from May to September during 2007, 2008 and 2009 to collect male moths that were then tested for resistance to a pyrethroid insecticide. Average survival at 5 µg/vial of cypermethrin over the three years was 16.3%, with Louisiana, Texas and Virginia exceeding 20% average survival. Average survival was higher in all states when compared to 1998 data. Survival during July and August is higher than survival in May or September. Carbon isotope analysis indicates that most of these mid- summer moths developed as larvae on grasses, most likely corn and sorghum. Monitoring will continue in the future to document the impact of newer transgenic corn varieties that are more toxic to bollworms. [ABSTRACT FROM AUTHOR]

Trials were conducted during 2008 and 2009 to evaluate side dress applications of Temik to field borders for tarnished plant bug management. During 2008, trends for lower plant bug numbers and significantly lower plant bug numbers were observed for plots that received Temik. There were trend for higher yields and significantly higher yields observed at some sample locations within the Temik treated plots. Across all sample locations within plots, the plots treated with Temik produced significantly more yield compared to the non-treated plots. During 2009, plant bug numbers were lower compared to 2008. Few differences in plant bug numbers were observed during 2009. Yield analysis for 2009 has not been completed and is not included in this report. [ABSTRACT FROM AUTHOR]

The tarnished plant bug (TPB) is a major pest of cotton throughout the midsouthern region of the United States. Research was conducted during the squaring period from 2006 to 2008 in all 5 states of the Midsouth to evaluate thresholds in the current production environment. These data show that costs associated with TPB are minimized when average TPB density is 8 per 100 sweeps and when average square retention is 90%. Existing thresholds of 8 TPB per 100 sweeps and square retention of 80% are supported by these data and should be retained. More aggressive management resulted in both reduced yield and higher control costs and should be avoided. [ABSTRACT FROM AUTHOR]

Two field experiments were conducted to evaluate the performance of selected insecticides for the control of tarnished plant bug (Lygus lineolaris). In trial 1, treatments containing Bidrin, acephate, and Endigo reduced plant bug numbers compared to the check at 7 DAT. In trial 2, most treatments in the trial controlled plant bugs compared to the untreated check at 7 DAT including Bidrin, acephate, Vydate, dimethoate, Carbine, Centric, and Trimax Pro. These data suggest that growers currently have a multitude of insecticide options for control of tarnished plant bug in cotton. [ABSTRACT FROM AUTHOR]

In 2007, VipCot was evaluated in two trials in Jefferson and Desha Counties to determine the efficacy of this new transgenic for control the heliothine complex and other lepidopterous pests. Significant differences were observed among treatments for seasonal total damage and seasonal total for heliothine larvae at both locations and VipCot was shown to be efficacious for looper control at the Desha Co. location. [ABSTRACT FROM AUTHOR]

An abstract of the article "A MidSouthern Perspective on Hemipteran Pests," by Ralph D. Bagwell, B. R. Leonard, Fred Musser, Angus Catchot, D. R. Cook, Scott D. Stewart, Kelly V. Tindall, Glenn Studebaker, D. Scott Akin and Gus M. Lorenz is presented.

Two field experiments were conducted to evaluate the performance of selected insecticides for the control of tarnished plant bug (Lygus lineolaris). In trial 1, treatments containing Bidrin, acephate, and Endigo reduced plant bug numbers compared to the check at 7 DAT. In trial 2, most treatments in the trial controlled plant bugs compared to the untreated check at 7 DAT including Bidrin, acephate, Vydate, dimethoate, Carbine, Centric, and Trimax Pro. These data suggest that growers currently have a multitude of insecticide options for control of tarnished plant bug in cotton. [ABSTRACT FROM AUTHOR]

In 2007, VipCot was evaluated in two trials in Jefferson and Desha Counties to determine the efficacy of this new transgenic for control the heliothine complex and other lepidopterous pests. Significant differences were observed among treatments for seasonal total damage and seasonal total for heliothine larvae at both locations and VipCot was shown to be efficacious for looper control at the Desha Co. location. [ABSTRACT FROM AUTHOR]

The article discusses a study which evaluates thresholds before and during bloom for the bug complex presented during the 2008 Beltwide Cotton Conferences in Nashville, Tennessee on January 8-11, 2008. In this study the researchers monitor weekly treatment process for large field plots of Bt cotton with tarnished plant bug (TPB), arranged in a randomized complete block with 4 replications during pre-bloom and flowering of cotton. The results of the study show that weekly insecticide applications may not be enough to preserve yield under severe infestations and no significant yield differences among treatments were noted in the pre-bloom thresholds. Also, in the bloom thresholds the TPB density never reached the high threshold and no significant differences of treatments were noted.

In the search for novel and commercially viable utilization of nonwoven fabrics, this study had the objective of determining whether nonwoven mats, which were made from biodegradable natural fibers of cotton and flax, could be used for the adsorption and removal of a ubiquitous pollutant of water and wastewater, namely copper ions. Nonwoven mats were manufactured with various blends of short and long staple cotton and flax and were subsequently treated with citric acid. The treated mats were monitored for citrate uptake, copper ion adsorption and fabric strength as compared with the control non-treated mats. The results demonstrate that mats made from 100% flax took up more citrate and copper than did mats made from 100% cotton. The flax-cotton blends had chemical properties which were arithmetic means of the individual components. The tensile parameters were not simple arithmetic means. Citric acid treatment diminished tensile parameters as compared to untreated mats for all cottonflax compositions. Treated cotton, flax and flax-cotton blended fiber mats represent a potentially biofriendly and convenient method for the removal of metal ions from water and wastewater streams. [ABSTRACT FROM AUTHOR]

In the search for novel and commercially viable utilization of nonwoven fabrics, this study had the objective of determining whether nonwoven mats, which were made from biodegradable natural fibers of cotton and flax, could be used for the adsorption and removal of a ubiquitous pollutant of water and wastewater, namely copper ions. Nonwoven mats were manufactured with various blends of short and long staple cotton and flax and were subsequently treated with citric acid. The treated mats were monitored for citrate uptake, copper ion adsorption and fabric strength as compared with the control non-treated mats. The results demonstrate that mats made from 100% flax took up more citrate and copper than did mats made from 100% cotton. The flax-cotton blends had chemical properties which were arithmetic means of the individual components. The tensile parameters were not simple arithmetic means. Citric acid treatment diminished tensile parameters as compared to untreated mats for all cotton- flax compositions. Treated cotton, flax and flax-cotton blended fiber mats represent a potentially biofriendly and convenient method for the removal of metal ions from water and wastewater streams. [ABSTRACT FROM AUTHOR]

A series of nonwoven fabrics composed of different ratios of cotton to flax were manufactured using a drylaid needlepunching system. The percentage of cotton was varied from 100% to 0% to determine the effect of blend composition and fiber quality on several different physical properties. Blending cotton with flax in needlepunched nonwovens increased tensile, tearing and bursting strength, and influenced other properties normally affected by a high percentage of flax such as stiffness and resilience. These improved characteristics could contribute to greater industrial use of lower grades of cotton as well as expand potential for developing markets for two biobased fibers. Continuing research is focused on identifying an optimum blend level and fiber quality for value added industrial end uses. [ABSTRACT FROM AUTHOR]

Laboratory studies were conducted to quantify toxin levels in bolls located at various locations throughout dual-toxin Bt cotton plants. Results of ELISA techniques indicate that there was a significant quadratic relationship between node location and Cry2Ab concentration, with expression levels highest in bolls from the central portion of the plant. For bolls at node 9 and above (averaged over positions 1 and 2), there was a significant decline in Cry2 expression as the season progressed. A more dramatic reduction of Cry2Ab levels was noted above node 16 in bolls from position land node 14 in bolls from position 2. Since bolls from these locations are from the same cohort (i.e., the same phenological age), this would indicate that environmental factors may play a significant role in expression of Bt toxins throughout the plant. [ABSTRACT FROM AUTHOR]

Small-plot experiments were conducted across the cotton belt to determine if automatic foliar applications made to cotton that had received a preventative insecticide would be economically viable, and if so, which timing these applications would most contribute to yield. Many locations received excessive rainfall in 2009, which confounded data from these areas. Therefore, only two locations are briefly summarized here. These trials will be conducted at least one more season across all (20+) locations from Texas to Virginia to determine the value of automatic insecticide applications for thrips following preventative insecticides. [ABSTRACT FROM AUTHOR]

Large-plot experiments were conducted throughout Arkansas to determine economic benefit of Bt cotton varieties in 2007 and 2008. Non-Bt, Bollgard, Bollgard II, and WideStrike varieties were each treated on an as-needed basis with insecticide for all pests. Yield was collected and all locations were subjected to economic analysis. Results from these studies suggest that when considering overall yield, the type of transgenic Bt was not as important as the variety itself. This is likely due to the overall lack of pressure from caterpillar pests across all locations both years. There are obvious advantages to the dual-gene products such as Bollgard II® and WideStrike® for management of lepidopteran pests, but this advantage does not necessarily translate to higher yields, most notably in the absence of these pests. That said, dual-toxin Bt cottons may prove to be more valuable than single-toxin technology during a year that may undergo heavier bollworm flights, or perhaps even a significant fall armyworm or looper migration. As for grower profit, varieties containing WideStrike resulted in the best net revenue across these particular trials. It should be noted, however, that these results may differ with a change in certain variables (e.g., higher bollworm pressure, change in technology fee, yield potential). [ABSTRACT FROM AUTHOR]

Two morphologically identical host strains of FAW, fall armyworm (J. E. Smith), exist that differ in plant host use, although both strains can be found in cotton. Little is known about interplant movement and damage potential of FAW larvae from either host strain in cotton, particularly second-generation Bt cotton. Thus, a field study was designed to determine possible behavior differences between the corn- and rice-strains of FAW on non-Bt, Bollgard II, and WideStrike cotton. Third-instar FAW were placed individually onto either white flowers or 7-d-old bolls on individual cotton plants of each variety and were evaluated at 6, 24, and 48 h after infestation. Comparison of larval movement away from infested reproductive structures did not differ among strains, cotton varieties, infested reproductive structure, or time after infestation. An interaction was found with regard to the level of feeding damage to reproductive structures. No difference in damage was found between FAW host strains when infested on non-Bt white flowers or bolls. Averaged across host strains, significantly more structures were damaged at 24 and 48 h after infestation than at 6 h after infestation. For white flowers infested in Bollgard II, the corn-strain caused more damage to reproductive structures at 48 h compared to damage by either strain at other evaluation periods. No differences were observed with regard to FAW damage potential for infested Bollgard II bolls or for infested white flowers or bolls of WideStrike. These results indicate that behavioral differences of the FAW host strains may be difficult to identify on cotton. However, damage to reproductive structures was found in all cotton varieties, particularly for the corn-strain. [ABSTRACT FROM AUTHOR]

An abstract of the article "Scouting Methods and Thresholds: We Have Work to Do in the Midsouth," by B. R. Leonard and R. Bagwell is presented.