Corn gluten meal application methods for organic weed control and squash production

Authors: Webber Iii, Charles; SHREFLER, JAMES - OSU, LANE, OK

Submitted to: Proceedings of Horticultural Industry Show
Publication Type: Proceedings
Publication Acceptance Date: 12/3/2006
Publication Date: 5/1/2007
Citation: Webber III, C.L., Shrefler, J.W. 2007. Corn gluten meal application methods for organic weed control and squash production. Proceedings of the 26th Oklahoma-Arkansas Horticultural Industry Show, January 5-6, 2007, Ft. Smith, Arkansas. 25:112-114.

Interpretive Summary: Methods need to be developed and evaluated for the safe application of corn gluten meal (CGM) to direct-seeded vegetables. CGM has been identified as a potential organic preemergence and preplant-incorporated herbicide. It is an environmentally friendly material that has demonstrated ability to decrease seedling development and plant survival by inhibiting root and shoot development. Unfortunately, CGM can also decrease the development and plant survival of direct-seeded vegetable crops. As a result, the use of CGM is not recommended in conjunction with direct-seeded vegetables. The development of equipment to apply CGM in banded configurations has created an opportunity to investigate whether banded CGM applications will provide significant crop safety for direct-seeded vegetables. The objective of this research was to determine the impact of banded corn gluten meal applications on squash plant survival and yields. A field study was conducted on 32-inch (81-cm) wide raised beds at Lane, OK with two application configurations (banded and solid), two CGM formulations (powdered and granulated), two incorporation treatments (incorporated and non-incorporated), and three application rates [5, 10, and 15 lb/100 ft**2 (250, 500, and 750 g/m**2)]. The two CGM formulations at three application rates were uniformly applied in both banded and solid patterns. The banded application created a 3-inch (7.6-cm) wide CGM-free planting zone in the middle of the raised bed. The CGM applications were then either incorporated into the top 1 to 2 inches (2.5 to 5.0 cm) of the soil surface with a rolling cultivator or left undisturbed on the soil surface. ‘Lemondrop’ summer squash (Cucurbita pepo L.) was then direct-seeded into the center of the raised beds. When averaged across the other factors, there was no significant difference between powdered and granulated CGM formulations or incorporating and non-incorporating the CGM for either squash plant survival or yields. CGM application rates did affect crop squash survival and yields when averaged across all other factors. As the CGM application rates increased the plant survival and yields decreased. When averaged across all other factors, the banded application resulted in significantly greater crop safety (90% plant survival) and yields (180 cartons/a) than the broadcast (solid) applications (45% plant survival and 127 cartons/a). The research demonstrated the potential usefulness of CGM in direct-seeded squash production, if used in banded application configuration. Additional research should further investigate the interaction of CGM application rates and the width of the CGM-free zone on crop safety for various vegetables.

Technical Abstract: Corn gluten meal (CGM) has been identified as a potential organic preemergence and preplant-incorporated herbicide. It is an environmentally friendly material that has demonstrated ability to decrease seedling development and plant survival by inhibiting root and shoot development. Unfortunately, CGM can also decrease the development and plant survival of direct-seeded vegetable crops. As a result, the use of CGM is not recommended in conjunction with direct-seeded vegetables. The development of equipment to apply CGM in banded configurations has created an opportunity to investigate whether banded CGM applications will provide significant crop safety for direct-seeded vegetables. The objective of this research was to determine the impact of banded corn gluten meal applications on squash plant survival and yields. A field study was conducted on 32-inch (81-cm) wide raised beds at Lane, OK with two application configurations (banded and solid), two CGM formulations (powdered and granulated), two incorporation treatments (incorporated and non-incorporated), and three application rates [5, 10, and 15 lb/100 ft**2 (250, 500, and 750 g/m**2)]. The two CGM formulations at three application rates were uniformly applied in both banded and solid patterns. The banded application created a 3-inch (7.6-cm) wide CGM-free planting zone in the middle of the raised bed. The CGM applications were then either incorporated into the top 1 to 2 inches (2.5 to 5.0 cm) of the soil surface with a rolling cultivator or left undisturbed on the soil surface. ‘Lemondrop’ summer squash (Cucurbita pepo L.) was then direct-seeded into the center of the raised beds. When averaged across the other factors, there was no significant difference between powdered and granulated CGM formulations or incorporating and non-incorporating the CGM for either squash plant survival or yields. CGM application rates did affect crop squash survival and yields when averaged across all other factors. As the CGM application rates increased the plant survival and yields decreased. When averaged across all other factors, the banded application resulted in significantly greater crop safety (90% plant survival) and yields (180 cartons/a) than the broadcast (solid) applications (45% plant survival and 127 cartons/a). The research demonstrated the potential usefulness of CGM in direct-seeded squash production, if used in banded application configuration. Additional research should further investigate the interaction of CGM application rates and the width of the CGM-free zone on crop safety for various vegetables.