Access the full text.
Sign up today, get DeepDyve free for 14 days.
References for this paper are not available at this time. We will be adding them shortly, thank you for your patience.
(F58) COTTON: Gossypium hirsutum L.; 'Deltapine 436RR' C. G. Sansone Texas Cooperative Extension District 7 Extension Center 7887 US Highway 87 N San Angelo, TX 76901-9714 Phone: (325) 653-4576 Fax: (325) 655-7791 E-mail: c-sansone@tamu.edu D. A. Mott Texas Cooperative Extension 3151 Innerloop, Ste. A Georgetown, TX 78626 Phone: (512) 943-3300 Fax: (512) 943-3301 E-mail: d-mott@tamu.edu Bollworm (BW): Helicoverpa zea (Boddie) Cotton was planted on 10 Apr into a Houston clay in 38-inch rows in central Tx near Taylor. The fertility and herbicide programs followed Extension recommendations for cotton in this region. Plot size was 75 ft x 4 rows with four replications in a RCB design. Insecticide applications were made on 28 Jun, at first bloom, with a self-propelled CO - pressurized sprayer calibrated to deliver 8.0 gpa at 30 psi with three TX-6 hollow cone nozzles per row. The adjuvant Kinetic (0.25% v/v) was added to the Denim treatment, and Steward was applied with Agri-Dex, a crop oil concentrate (0.5% v/v). The treatments were evaluated on 1 and 5 Jul. A random plant from one of the two center rows of the plot was selected, which served as a starting point to begin making counts. Ten consecutive plants were visually inspected for number of bollworm larvae and bollworm eggs from one of the center two rows of each plot. In addition, 25 squares were randomly pulled from the center two rows of each plot and all bollworm damaged fruit was counted and recorded. Yield was taken by harvesting 1/1000 acre from each of the middle two rows of each plot. All data were analyzed using ANOVA and LSD (P ≤ 0.05). Percent control was calculated using Henderson's formula. Bollworm populations were consistently high throughout the trial and egg deposition was consistent in all the plots with no significant differences. Three DAT, all the treated plots had significantly lower bollworm numbers than the untreated control (Table 1). Damaged fruit counts were not significantly different. Five days after treatment, none of the treated plots had significantly lower bollworm numbers than the untreated although a trend existed for lower numbers in the treated plots. Only the Tracer and F0570 were effective at lowering numbers below threshold levels. Treatment efficacy started to decline in all plots with only the F0570 providing 70% control. No significant differences were found between yields (Table 2). However, when yields are compared to average number of larvae per ten plants and average percent control, the trend favored higher yields with the more efficacious treatments.
Arthropod Management Tests – Oxford University Press
Published: Jan 1, 2004
You can share this free article with as many people as you like with the url below! We hope you enjoy this feature!
Read and print from thousands of top scholarly journals.
Already have an account? Log in
Bookmark this article. You can see your Bookmarks on your DeepDyve Library.
To save an article, log in first, or sign up for a DeepDyve account if you don’t already have one.
Copy and paste the desired citation format or use the link below to download a file formatted for EndNote
Access the full text.
Sign up today, get DeepDyve free for 14 days.
All DeepDyve websites use cookies to improve your online experience. They were placed on your computer when you launched this website. You can change your cookie settings through your browser.