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An ongoing experiment to develop a cotton cultivar resistant to the West Texas thrips complex is being conducted. Numerous resistant cottons have been identified. The best of these was crossed to breeding program elites and tested under field conditions. A 2009 field trial indicates that the resistance was inherited. Selections were made to allow development to continue. [ABSTRACT FROM AUTHOR]

Over 500 cottons from the various collections around the world were characterized using descriptors of morphological traits and digital photography. This information will eventually be incorporated into a database for use by fellow scientists when selecting traits in a breeding program. [ABSTRACT FROM AUTHOR]

The Arkansas Boll Weevil Eradication Program (ABWEP) was initiated in 1997 to rid the state of the boll weevil Anthonomus grandis Boheman. The Arkansas program began in the Southwest zone in 1997 with the diapause phase, followed by season-long phases in 1998, 1999, 2000, 2001, and season-long maintenance phases in 2002, 2003, 2004, 2005, 2006, 2007 and 2008. The seasonal mean number of boll weevils captured per trap per week in 2008 was significantly less than in 1998. The mean in 2008 was 0.0 weevils per trap per week, and in 1998 it was 3.99, a reduction rate of 100%. Insecticide applications in 2008 for boll weevils were reduced by 100.0%, compared to 1998. The program expanded into the Southeast zone in 1999 with the diapause phase, followed by season-long phases in 2000, 2001, 2002, 2003 and season-long maintenance phases in 2004, 2005, 2006, 2007 and 2008. The seasonal mean number of boll weevils captured per trap per week in 2008 was significantly less than in 2000. The mean in 2008 was 0.000771, and in 2000 it was 5.54, a reduction rate of 99.986%. Insecticide applications made by the program in 2008 were less than in 2000 by 98.05%. The program expanded into the Central zone in 2000 with the diapause phase of the program followed by a seasonlong phase in 2001, 2002, 2003 and 2004, and season-long maintenance phases in 2005, 2006, 2007 and 2008. The seasonal mean number of boll weevils captured per trap per week in 2008 was significantly less than in 2000. The mean in 2008 was 0.0, and in 2000 it was 15.66, a reduction rate of 100.0% in 2008 when compared with 2000. Insecticide applications made by the program in 2008 were less than in 2000 by 100.0%. The program expanded into the Northeast Ridge zone in 2001 with the diapause phase, followed by a season-long phase in 2002, 2003, 2004 and 2005, and season-long maintenance phase in 2006, 2007 and 2008. The seasonal mean number of boll weevils captured per trap per week in 2008 was significantly less than in 2001. The mean in 2008 was 0.0, and was 8.70 in 2001, a reduction rate of 100.0%. Insecticide applications made by the program in 2008 were less than in 2002 by 100.0%. The program expanded in the Northeast Ridge Zone to include Eastern Poinsett in 2002 with the diapause phase, followed by a season-long phase in 2003, 2004, 2005 and 2006, and season-long maintenance phase in 2007 and 2008. The seasonal mean number of boll weevils captured per trap per week in 2008 was reduced when compared to the trapping program in 2001. The mean in 2008 was 0.0, and was 11.79 in 2001, a reduction of 100.0%. The program expanded into the Northeast Delta Zone in 2003 with the diapause phase, followed by a season-long phase in 2004, 2005, 2006 and 2007, and season-long maintenance phase in 2008.… [ABSTRACT FROM AUTHOR]

Stink bugs (Hemiptera: Pentatomidae) are normally classified as occasional pests of upland cotton (Gossypium hirsutum L.) in the Texas High Plains (THP) region. Understanding where cotton arthropod pest species, such as stink bugs (SB), feed, and possibly more importantly, where these pests reproduce can be useful in creating insect management strategies for the THP and other areas. A study was conducted during the February to November periods of 2004 and 2005 to determine the seasonal abundance and reproduction of SB species on cotton, alfalfa, and over 20 prevalent THP weed species. Over the 2-year study period, a total of 224,509 plant sweeps yielded 5,794 SB adults and 362 nymphs. These specimens were placed into one of two groups: Green Stink Bugs (GSB) is comprised of two species, [green SB, Acrosternum hilare (Say); southern green SB, Nezara viridula (L.)] while the second group, referred to as the Brown Stink Bugs (BSB), contains only one species [brown SB, Euschistus servus (Say)]. For each of five 2-month sampling periods (Feb/Mar, Apr/May, Jun/Jul, Aug/Sep, Oct/Nov), the plant species which yielded the highest numbers of adult and immature stink bugs are discussed. Based upon selected SB species groupings (GSB and BSB), it does not appear that the compositions of these groupings vary greatly across study year or the north/south geographical gradient. During the first four sampling periods (February-September) the GSB group dominated (ca. 75:25 ratio) the overall SB population, whereas during the Oct/Nov sampling period we observed increasing number of BSB (ca. 50:50 ratio). Knowledge related to stink bugs and their preferred THP 'hosts' will hopefully result in quicker development of management strategies for areas experiencing problems with stink bugs on cotton or other crops. [ABSTRACT FROM AUTHOR]

An on-going survey for Lygus bugs was conducted in the Texas High Plains in 2004. Cotton and 21 potential non-cotton hosts were surveyed using a heavy-duty sweep net (100-150 sweeps/habitat/site) in three counties representing northern (Hale), central (Lubbock), and southern (Dawson) areas of this intensive cotton-growing region. Numerically dominant wild hosts found in roadside ditches and in and around cultivated fields were surveyed throughout the study period. Sampling was conducted on a weekly basis beginning in early February for wild hosts and in early July for cotton. As of November 2004, totals of 87,134 and 17,950 sweeps were taken in non-cotton hosts and cotton, respectively. A total of 19,148 adult Lygus and 7,628 nymphs have been captured to date. An overall sex ratio of 50.7:49.3 (M/F) was found for the Lygus adults. Wild mustards and alfalfa harbored the highest numbers of Lygus in the early and late season periods. Some important mid-season wild hosts included alfalfa, pigweed, ragweed, Russian thistle, smartweed and yellow sweetclover. The similar host-plant preference ratings between adults and nymphs suggest a strong positive correlation between adult population levels and the amount of reproduction within individual host-plant species. Lygus numbers in cotton were uniformly low relative to many non-cotton hosts, indicating that cotton is not a preferred feeding or breeding host. To date in 2004, the overall species complex observed in non-cotton hosts consisted of 96.5, 1.8, and 1.7% L. hesperus Knight, L. elisus Van Duzee, and L. lineolaris (Palisot de Beauvois), respectively, while in cotton the complex consisted of 91.8% L. hesperus with only two specimens each of L. elisus and L. lineolaris retrieved from cotton samples. With the exception of pigweed and ragweed, all other preferred host-plants and cotton showed L. hesperus percentages ranging from 90.3 to 100%. This comprehensive survey supports reports in the literature that Lygus are strongly polyphagous, based on the detection of Lygus throughout the season on available non-cotton hosts. This ability to utilize a succession of common non-cotton hosts allows Lygus to build large populations in wild hosts and invade cotton if conditions are favorable. Sampling is still continuing though 2005. [ABSTRACT FROM AUTHOR]

The study was conducted at the AG-CARES farm in Lamesa, Texas to quantify the seasonal activity patterns of the western flower thrips, Frankliniella occidentalis (Pergande), and cotton fleahoppers, Pseudatomoscelis senates (Reuter). Thrips infestation started from cotyledon stage. Thrips showed two distinct peak populations, one at 1-2 true leaf stage (20 DAP) and another at flowering stage (82-96 DAP). In the first peak, thrips numbers reached up to 6.1 total thrips per plant and the number slowly declined as the plant matured and began squaring. However, once cotton started flowering (75 DAP), thrips population began to grow and attained the second peak in the second week of August (96 DAP); the second peak was larger than the first peak. Fleahopper activity began 44 days after planting and showed only one peak in early square stage (103 DAP). Seasonal average fleahoppers were found significantly higher in late-planted cotton (2705 per acre) compared with that in timely planted cotton (1118 per acre). The tillage system and variety did not have a significant influence on abundance pattern of thrips or fleahoppers. Visual sampling method detected the highest abundance of fleahoppers (37,851 per acre) followed by beat bucket (17,086 per acre), drop cloth (8,378 per acre), vacuum (951 per acre), and sweepnet (798 per acre) sampling. [ABSTRACT FROM AUTHOR]

Experiments were conducted to determine the potential threat of boll weevil transport on or in cotton modules constructed in infested areas to gins in weevil-free areas. Surveys in three areas of Texas indicated that live weevils are usually present in defoliated fields just before harvest and one can expect live weevils to he packed into modules. Most weevils dispersed rapidly from untarped module surface when temperatures were warm enough for flight, but a small percentage remained at least to 24 h. Most weevils trapped on the surface under the tarp died from high temperatures . Survival of weevils inside modules was high after 1 and 3 d, but had declined dramatically by 7 d. The greatest threat of reinfestation by weevils dispersing from a module would occur when a module is constructed and transported during cool, cloudy weather, followed by warm weather favorable for flight at the gin yard. Other experiments were conducted to determine boll weevil mortality in various subprocesses in a cotton gin by introducing known numbers of weevils at various points in the system and estimating survival. We found no evidence that weevils can survive in the seed cotton to the gin stand or beyond. The greatest threat for weevil survival and escape from the gin occurs soon after entry, with chances of survival diminishing rapidly the further the weevils progress through the different ginning processes . Small numbers of live weevils can he expected to escape into the rock trap, either as free adults or in infested bolls (Brashears et al. 2003). Thus, it is important that at-risk gins either destroy the trash collected in the rock trap immediately or collect it in a container that will not permit weevil escape. Weevils protected inside unopened bolls can escape alive with the gin trash later in the cleaning process even when passed through a high-speed trash fan. If a mechanical device can he designed and installed to slightly crack open bolls as they move to the fan, this latter problem can he mitigated to a great extent. [ABSTRACT FROM AUTHOR]

Western tarnished plant bug (WTPB) damage to cotton bolls decreased as bolls aged. As heat units accumulated past white flower, the number of external lesions as well as internal carpel wall warts decreased. Bolls that had only accumulated 150 heat units past white flower sustained the greatest amount of damage, while bolls accumulating 450 to 550 HU received the least. Results indicate that once have accumulated 350 HU past white flower they are relatively safe from internal injury caused by WTPB. A homemade penetrometer was constructed in order to be able to measure the resistance to penetration of a cotton boll carpel wall at different boll ages. This would permit measurements of differences due to factors such as irrigation and variety without actually having to repeat caged bug studies. Boll age was categorized using accumulated heat units, and bolls were tested for toughness as they aged. The pressure required to puncture a boll at all locations (the side, top or bottom) increased with increasing maturity. Results indicate that the side of the boll is the easiest to penetrate, therefore the most susceptible to WTPB damage. If a reliable tool to measure boll hardness was available, and the information obtained in this study used, a threshold to predict when a cotton boll is safe from WTPB injury could be established for bolls from different varieties and grown under different cultural practices. This would allow crop managers to avoid unnecessary late season plant bug applications after yield is no longer threatened. [ABSTRACT FROM AUTHOR]

Texas High Plains cotton losses due to beet armyworms, Spodoptera exigua (Hübner), have increased over the last ten years. This study was conducted in 2002 and 2003 to determine the influence of cotton planting date window (timely vs. late) and level of pigweed infestation (pigweed-infested vs. non-infested) on beet armyworm population abundance in Texas High Plains cotton. In both 2002 and 2003, planting date window did not influence seasonal differences in beet armyworm infestation. For both years, the presence or absence of pigweed contributed significantly to differences in seasonal beet armyworm activity in nearby cotton. In 2002, pigweed-infested cotton was observed to have a seasonal average of 3,240 larvae per acre compared with a significantly lower count of 1,015 larvae per acre in the clean-tilled non-infested cotton. Under lighter beet armyworm population levels in 2003, a seasonal average of 1,065 worms/acre was observed in pigweed-infested plots while only 195 worms/acre were detected in the plots without pigweed. The results of this study suggest that cotton fields infested with a preferred wild host, such as pigweed, have an increased risk for beet armyworm colonization. [ABSTRACT FROM AUTHOR]

Cotton planting date and cultivar were tested in 2002 and 2003 for their effect on populations of arthropod predators in cotton in the Texas High Plains. Timely and late cotton plantings were made, and four of the most common adapted stripper cultivars were used. Predators were sampled using five methods which were also evaluated for effectiveness. Seasonally, timely planted cotton had more total predators per acre in 2003, while cultivar ST 2454R had more total predators (also in 2003). In both years, the beat bucket was the most effective of the sampling methods tested, while the sweep net and vacuum sampler were the poorest. [ABSTRACT FROM AUTHOR]

Texas High Plains cotton losses due to beet armyworms have increased greatly over the last ten years. This study is being conducted to determine the influence of cotton planting date window (timely vs. late) and level of pigweed infestation (pig- weed-infested vs. non-infested) on beet armyworm population abundance in Texas High Plains cotton. Planting window and level of pigweed infestation both contributed to differences in seasonal beet armyworm activity. Significantly higher numbers of beet armyworm larvae were observed in the timely (10 May) planted cotton than in the late (14 June) planted cotton, with seasonal averages of 2579 and 1676 larvae per acre in the May and June planted cotton, respectively. Pigweed-infested cotton was observed to have a seasonal average of 3240 larvae per acre compared with a significantly lower count of 1015 larvae per acre in the clean-tilled non-infested cotton. Preliminary results suggest that cotton fields infested with a preferred wild host, such as pigweed, could have an increased risk for beet armyworm colonization. [ABSTRACT FROM AUTHOR]

Influence of irrigation application rates and irrigation application methods on cotton insect populations were studied in Texas High Plains during 2002. Cotton pests, including Lygus bugs and cotton fleahoppers, and beneficial arthropods were sampled. Three irrigation application rates, 50%, 75% and 100% evapotranspiration (ET) replacements, were evaluated. The two irrigation application methods evaluated were low energy precision application (LEPA) system and low elevation spray application (LESA) system. Four commercial cotton cultivars, ST2454R, PM2326RR, ST4793R and DPS41SRR were evaluated. Insect populations were sampled using a vacuum sampler. Insect numbers were higher in LEPA irrigated plots than in LESA irrigated plots. Overall, insect numbers were higher at 75% ET replacement followed by 100% and 50%, respectively. The cultivar PM2326RR had the highest Lygus and fleahopper numbers and lowest predators compared with the other three cultivars. [ABSTRACT FROM AUTHOR]

Based on data collected from a two-year Texas High Plains field survey of Lygus and their associated crop and weed hosts, three different kinds of regression models (simple linear regression, polynomial regression and Logistic Growth Curve regression) were constructed to quantify the Lygus preference caused by four selected host plants, plant growth stage and geographical location. Weather data were also regressed on Lygus counts. The results produced models with some significant trends, but very poor fits, indicating a much more complex dataset with more regressor variables will be required to produce good predictive models. [ABSTRACT FROM AUTHOR]

Seasonal abundance of fleahoppers and Lygus varied with cotton cultivar as well as the planting date window. Paymaster 2326RR had the most fleahoppers and Lygus compared with Stoneville 2454R, Paymaster 2145RR, and Paymaster 2167RR. Late-planted cotton attracted significantly more of both species compared with the timely planted cotton. Sampling methods varied in their efficiency to capture fleahoppers and Lygus. The beat bucket method captured significantly more Lygus, while the visual method accounted for the most fleahoppers compared with other sampling methods. [ABSTRACT FROM AUTHOR]