Bollworm larva on boll.
However recently thisFigure 1. Eggs are spherical, flattened, with 10 to 15 perpendicular rows of toothed ribs. Cotton is susceptible to a wide range of pests, so it’s only natural that insect management is one of the highest variable costs associated with producing the crop.This year, as growers prepare for the upcoming cotton growing season, entomologists across the Cotton Belt are calling attention to an emerging pest issue — bollworm resistance in dual-gene Cotton Incorporated’s resident entomologist Dr. Ryan Kurtz spearheads the company’s insect management research effort.Although it is too early to tell what the extent of bollworm resistance will be in dual-gene “If we see a large number of bollworms successfully come through Bollworms have always been a known pest of cotton but have not been the major pest of concern for some time. BG2= Bollgard 2, BG3 = Bollgard 3. Recently, action thresholds have been changed in cotton to reflect problems associated with Bt resistance (Table 3).A unique education agency, the Texas A&M AgriLife Extension Service teaches Texans wherever they live, extending research-based knowledge to benefit their families and communities.AgriLife Extension's online Bookstore offers educational information and resources related to our many areas of expertise and programming; from agriculture, horticulture, and natural resources to nutrition, wellness for families and youth, and much more.Click for a hub of Extension resources related to the current COVID-19 situation. Bacillus thuringiensis Cry and Cyt protein families are a diverse group of proteins with activity against insects of different orders - Lepidoptera, Coleoptera, Diptera and also against other invertebrates such as nematodes. corn earworm or sorghum headworm) is a serious pest in the southern cotton growing areas. With this much money at stake, producers are looking for methods to ensure their crops will be successful. Presence of Multiple cry Genes in Bacillus thuringiensis Isolated from Dead Cotton Bollworm Heliothis armigera S. Khojand 1, M. Keshavarzi 2*, K. Zargari 3, H. Abdolahi 2, and F. Rouzbeh 4 ABSTRACT Cry genes encoding Cry proteins toxic to Lepidoptera, Coleoptera and Diptera species Dominant point mutation in a tetraspanin gene associated with field-evolved resistance of cotton bollworm to transgenic Bt cotton. Bollworm injury to cotton in the Brazos River Bottom in 2017. “Growers should follow university Extension Service recommendations to ensure proper selection of insecticides, rates, and timings to maximize control with foliar insecticides.”
*Red line represents economic threshold.Figure 2.
In Kansas cotton, infestations are sometimes observed, although damage has been limited even when high infestations have developed in … It should not be confused with the similarly named, related species Helicoverpa zea. Dr. Dominic Reisig, associate professor, North Carolina State University, says, “The caterpillar pest of most concern to cotton has typically been the tobacco budworm.”However, bollworms have always been more tolerant of Cotton Incorporated has invested in a myriad of projects to address this resistance issue and ultimately boost growers’ bottom line.
Description of the Pest. Percentage of corn ears with large corn earworms.
The inclusion of the Cry2 toxins had greatly increased the effectiveness to bollworm. NBT = Non-Bt, WS = WideStrike, WS3 = WIdeStrike 3, BG2 = Bollgard 2, TL = TwinLink. Some of the projects focus on techniques to improve resistance monitoring.“Once we identify resistant populations, we try to dig deeper and understand the characteristics specific to that population so we can better control it,” Kurtz says.Because of the increased resistance, cotton growers saw significantly more damage from bollworms in their 2017 crop.In response, a group of Mid-South and Southeast entomologists have been working to refine thresholds, so they can better inform growers when to spray their dual-gene Another Cotton Incorporated project done in conjunction with Mississippi State University is looking at computer modeling to simulate scenarios for resistance development to the newer three-gene Since bollworm resistance is expected again this year, cotton growers should enter the season with a plan and be prepared to scout and spray dual-gene “Timing of foliar applications will be critical,” Kurtz says.
All Rights Reserved. © 2007 - 2020 One Grower Publishing. Because of the overlap between Bt cotton and Bt corn traits, there is great concern regarding selection for Bt resistance in bollworm/earworm. by John L. Few IV, IPM Agent in Southern Blacklands and Dr. David Kerns, Extension Entomologist in College StationCotton and corn are major cash crops in Texas with a market value of over 3 million dollars combined in 2016. Proceedings of …
Comparative bollworm injury of a non-Bt cotton relative to Bollgard 2 and Bollgard 3 in the Brazos River Bottom in 2017.