Submitted to: Oklahoma Agriculture Experiment Station Departmental Publication
Publication Type: Experiment Station
Publication Acceptance Date: April 15, 2006
Publication Date: May 1, 2006
Citation: Webber III, C.L., Russo, V.M., Shrefler, J.W. 2006. Corn gluten meal as a herbicide in non-pungent jalapeno peppers. 2005 Vegetable Trial Report, Oklahoma State University, Division of Agricultural Sciences and Natural Resources, Department of Horticulture and Landscape Architecture. Stillwater, OK. MP-164, p. 57-58.
Corn gluten meal (CGM) has been identified as a potential organic preemergence and preplant-incorporated herbicide. It is an environmentally friendly material that has a demonstrated ability to decrease seedling development and plant survival by inhibiting root and shoot development. Non-pungent jalapeno peppers are used for making commercial picante sauces (salsas). The objective of this research was to determine the impact of corn gluten meal applications on non--pungent jalapeno pepper yields. A factorial field study was conducted during the summer of 2005 on 36-inch wide raised beds at Lane, OK with two incorporation treatments (incorporated and non-incorporated), and two application rates (7.5 and 15 lb/100 ft**2 ). The experiment included a weedy (no weed control) and a weed-free (hand weeded) check for each incorporation treatment. The CGM applications were then either incorporated into the top 1 to 2 inches of the soil surface with a rolling cultivator or left undisturbed on the soil surface. Pace 105 non-pungent jalapeno peppers were transplanted on May 6, 2005 with a 1.5-ft spacing between plants within the rows. Pepper yields ranged from 7.0 t/ac, the weed-free non-incorporated treatment, to 0.2 t/ac, weedy-check incorporated treatment. Although there were initial reductions in weed densities as a result of CGM applications, there were no observable reductions in weed densities or differences at harvest compared to the weedy check treatments. Marketable and non-marketable pepper yields and numbers reflected the final weed densities with no significant differences between the CGM treatments and the weedy checks. Pepper yields and number were always significantly greater for the weed-free treatments compared to the other weed control treatments. Marketable yields were also greater for the weed-free, non-incorporated treatment (7.0 t/ac), compared to weed-free, incorporated, treatment (5.7 t/ac). This difference most likely reflects the importance of having a firm bed surface for placing transplants and maintaining bed integrity after transplanting. The research demonstrated the need for additional weed control beyond that provided by CGM applications to prevent totally unsatisfactory yield reductions in non-pungent jalapeno peppers.