Degree Type


Date of Award


Degree Name

Master of Science






The number of herbicides available for use in strawberry (Fragaria xananassa Duch.) production is limited and declining. In order for strawberry growers to maintain current production and quality levels, alternative weed control strategies and products must be developed. Corn gluten hydrolysate (CGH) is a water-soluble form of corn gluten meal (CGM), a by-product of corn wet-milling. Both materials have shown herbicidal properties and can serve as a source of nitrogen (N) for plants. This study was conducted to determine whether CGH can be used to control weeds as a preemergence herbicide and act as an N source in strawberry production. Corn gluten hydrolysate, CGM, and urea, were applied at N rates of 0, 9.8, 19.5, and 29.3 g·m⁻². Dimethyl tetrachlorobenzenedicarboxylate (DCPA) was applied at 9 kg·ha⁻¹ to treatments with urea at N rates of 9.8, 19.5, and 29.3 g·m⁻². DCPA or N were not applied to 0 g·m⁻² treatment plots.Rates of product were based on equivalent amounts of N for each treatment. During the 1995 establishment season, all treatments were applied in June, July, and August; during the 1996, 1997, and 1998 growing seasons, treatments were applied in July and August only. Dicot and monocot weed number and weed shoot dry weights were determined twice each growing season, [Nearly equal to] 30 d after treatment applications in July and August. Strawberry yield, number, leaf N, and growth data were measured. Corn gluten hydrolysate controlled weed populations with varying success over the course of the study. In August, 1996 and 1998, application of CGH reduced dicot weed number by 119% and 143%, respectively, compared to the control. Corn gluten hydrolysate had no effect on monocot weed number. In 1998, plots that received CGH at 29.3 g·m⁻² had a strawberry fruit yield that was 173% greater, and berry number that was 112% greater, than the control. Efficacy of CGH may have been affected by environmental factors such as, timing of application, rainfall events and mirobial breakdown. Under certain conditions, CGH reduced dicot weed pressure and increased strawberry yield and plant development.


Copyright Owner

Craig Alan Dilley



OCLC Number


File Format


File Size

58 pages