Corncob Grits Research Articles

Effect of oxidized β-carotene on the growth and feed efficiency of broilers

Fully oxidized β-carotene (OxBC) containing β-carotene-oxygen copolymers is proposed as an alternative to antimicrobial growth promoters. Two trials were conducted to determine the efficacy of OxBC in enhancing growth and feed intake (FI) in male and female Ross × Ross 308 broilers in Ontario, Canada, and in Ross 308 male broilers in the United Kingdom. In the first trial, 0, 1, 2, or 5 ppm OxBC were added to diets in a 20% cornstarch premix, whereas in the second trial, 0, 2, or 5 ppm OxBC were added in a 1% cornstarch or 1% corncob grits premix. In trial 1, 2, and 5 ppm OxBC improved bird final body weights (BW) compared with the unsupplemented, nonmedicated (no bacitracin methylene disalicylate included), negative control birds after 39 d of feeding under commercial conditions (P < 0.05). All levels of OxBC improved feed conversion (FCR) during the finisher period (P < 0.05), whereas 2 and 5 ppm OxBC enhanced FCR relative to the negative control group during the full production cycle (P < 0.05). Average daily FI was not affected by OxBC, whereas 2 and 5 ppm OxBC increased broiler average daily gain (ADG) (P < 0.05). Oxidized β-carotene did not affect bird mortality. The optimal OxBC dose was 2 ppm under the conditions used. In trial 2, 2 or 5 ppm OxBC on cornstarch and 5 ppm OxBC on corncob grits improved ADG, BW, and FI when fed for 35 d, as compared with the negative, nonmedicated control (P < 0.05). Feed conversion was not improved in the OxBC groups compared with the control group (P > 0.05). There were no differences among the 3 OxBC groups (P > 0.05). When birds were fed 2 ppm OxBC on corncob grits, the overall ADG, BW, and FI were lower than the respective control values (P < 0.001). Overall bird mortality was higher than expected for all groups, including the control group, but no dose effect was evident. Cornstarch was the preferred carrier for OxBC, and 2 ppm OxBC was the optimal dose under the conditions used.

Organic fertilizer abrasive grits increase soil available nitrogen, plant height, and biomass

AbstractIn organic cropping systems, air‐propelled abrasive grits can be used to control in‐row weeds. If the applied abrasive grit is an approved organic fertilizer, these applications may serve a dual purpose of weed control and crop fertility. Laboratory soil incubations examined the N mineralization rates of several grit types with differing C/N ratios (Agra Grit [crushed walnut shells, 170:1], corncob grit [91:1], Sustane [composted turkey litter, 5.0:1], Phytaboost Plant Food [crushed and pelletized soybean meal, 5.0:1]). A greenhouse study determined plant wheat (Triticum aestivum L.), kale (Brassica napus pabluaria DC), and velvetleaf (Abutilon theophrasti Medik.) growth response in soils amended with these grits. The N mineralization rates varied by grit type, soil, and application rate. The N mineralized from Phytaboost within 56 d was similar among the amounts of N a whereas the amount of N mineralized from Sustane was inversely related to the amount of N applied. Agra Grit and corncob grit immobilized soil N due to their high C/N ratios. In soils amended with Sustane, plant height and biomass were 15–43% and 34–83% greater than for plants grown in soils with Agra Grit, corncob grit, and the nontreated soil. Applications of organic fertilizer as air‐propelled grit may improve crop growth; however, if weed control is imperfect, these grits may increase weed growth. Grits with high C/N ratios may immobilize soil available N but not affect plant growth.

Propelled Abrasive Grit for Weed Control in Organic Silage Corn

Core Ideas Air‐propelled corncob grit can control in‐row weeds in corn through abrasionA single grit application applied at V1 or V3 of corn increased silage yield.A single grit application applied at V5 or V7 suppressed weeds, but had lower silage yield. Weed management in organic farming requires many strategies to accomplish acceptable control and maintain crop yields. This 2‐yr field study used air propelled abrasive grit for in‐row weed control in organically certified silage corn (Zea mays L.). Corncob grit was applied as a single application at corn vegetative growth stages V1 (one true leaf; numbers correspond to number of true leaves at the corn vegetative stage), V3, or V5 (in 2013) and V3, V5, and V7 (in 2014) and in double and triple combinations at these stages. Between‐row weed control was accomplished by flaming or cultivation after the last grit application. Grit effects on weed efficacy and silage yield were quantified and compared with hand‐weeded and season‐long weedy treatments. Grit applications decreased in‐row weed biomass by &gt;80% and increased yield up to 250% when compared with the weedy check. Single early applications (V1 and V3) increased yield, with additional treatments decreasing end‐of‐season weed density and biomass. Single late grit applications (V5 and V7) also decreased weed biomass, but silage yields were reduced compared with hand‐weeded and early treatments. Early grit applications may have value for growers to control in‐row annual weeds in organic silage corn without soil disturbance.

Air-propelled abrasive grit can damage the perennial weed quackgrass

New techniques are needed to control quackgrass in organic crops. With ≥2 applications of abrasive air-propelled (800 kPa) corncob grit to 15-cm-tall quackgrass tillers, regrowth was minimal at 5 wk after treatment. Abrasive grits may be effective tools to help manage perennial weeds in organic row crops.

Spent Coffee Grounds as Air-Propelled Abrasive Grit for Weed Control in Organic Production

Spent coffee grounds (SCG) represent a significant food waste residue. Value-added uses for this material would be beneficial. Gritty agricultural residues, such as corncob grit, can be employed as abrasive air-propelled agents for organically-compatible and selective shredding of weed seedlings within established crops. SCG were tested and compared with corncob grit for their ability to injure seedlings of two important weeds: waterhemp and velvetleaf. Waterhemp seedlings were controlled completely with as little as 0.5 g of SCG at an air pressure of 690 kPa. Velvetleaf seedlings were much larger than those of waterhemp at the time of grit application, better tolerated SCG abrasion, but still were damaged appreciably by 1 to 2 g of grit. SCG were at least as effective for abrading weed seedlings as corncob grit, whose value for this purpose in organic crops was demonstrated previously.

Propelled abrasive grit applications for weed management in transitional corn grain production

AbstractWeed control is challenging to farmers who are transitioning from production systems that use synthetic herbicides to organic systems. A 2-year field study examined air-propelled corncob grit abrasion for in-row weed control efficacy and effect on corn yield. Grit was applied based on corn vegetative developmental stages with one (V1, V3 or V5), two (V1 + V3, V1 + V5, or V3 + V5), or three (V1 + V3 + V5) applications. Flame-weeding or cultivation was used after the V5 application for between-row weed control. Grit applications decreased in-row weed densities by about 60% (α = 0.05) and biomass up to 95% (α = 0.001). Between-row treatments provided similar control, and reduced weed biomass by 55% in 2013 (α = 0.01) and 86% (α = 0.001) in 2014. In-row grit treatments increased corn yield up to 44%, and yield was more influenced by in-row weeds than between row weeds. These results indicate that abrasive corncob grit for in-row weed control, supplemented with cultivation or flaming, can reduce weed biomass substantially and help maintain corn yield. However, timing and frequency of grit application need further refinement based on weed growth as influenced by climate, as treatments at similar corn growth stages did not consistently provide adequate weed control between years.

Integrating Weed and Vegetable Crop Management with Multifunctional Air-Propelled Abrasive Grits

Abrasive weed control is a novel weed management tactic that has great potential to increase the profitability and sustainability of organic vegetable cropping systems. The objective of this study was to determine the effect of air-propelled organic abrasive grits (e.g., organic fertilizers) on weed seedling emergence and growth and vegetable crop growth. A series of thirteen greenhouse trials were conducted to determine the susceptibility of weeds to abrasive weed control with one of six organic materials including: corn cob grits, corn gluten meal, greensand fertilizer, walnut shell grits, soybean meal, and bone meal fertilizer. In addition, crop injury was quantified to determine the potential utility of each organic material as abrasive grits in tomato and pepper cropping systems. Of the six organic materials, corn gluten meal, greensand fertilizer, walnut shell grits, and soybean meal provided the broadest range of POST weed control. For example, one blast of corn gluten meal and greensand fertilizer reduced Palmer amaranth (one-leaf stage) seedling biomass by 95 and 100% and green foxtail (one-leaf stage) biomass by 94 and 87%, respectively. None of the organic materials suppressed weed seedling emergence when applied to the soil surface, suggesting that residual weed control with abrasive grits is unlikely. Tomato and pepper stems were relatively tolerant of abrasive grit applications, though blasting with select materials did increase stem curvature in tomato and reduced biomass (corn cob grit) and relative growth rate (corn gluten meal and greensand) in pepper. Results suggest that organic fertilizers can be effectively used as abrasive grits in vegetable crops, simultaneously providing weed suppression and supplemental crop nutrition. Field studies are needed to identify cultural practices that will increase the profitability of multifunctional abrasive weed control in organic specialty crops.

Soybean Seedlings Tolerate Abrasion from Air-Propelled Grit

New tools for controlling weeds would be useful for soybean production in organic systems. Air-propelled abrasive grit is one such tool that performs well for in-row weed control in corn, but crop safety in soybean is unknown. Responses to abrasion by corn-cob grit of soybean seedlings were examined at VE, VC, VU, V1, V2 (emergence, cotyledon, unifoliate, first trifoliate, and second trifoliate, respectively) and combinations of these growth stages, in both greenhouse and field settings. Seedling leaf areas and dry weights in greenhouse experiments were reduced by treatments that included abrasion at VC, with the primary effect expressed through reductions in the size of the unifoliate leaf. In the field, soybean stand also was reduced by grit applications at VC, especially if followed by a second application at VU or V1. However, soybean yield was not reduced by grit applied at any soybean stage of growth. End-of-season weed dry weights did not differ from hand-weeded checks, and weeds did not impact soybean yields. Thus, abrasive grit for in-row weed control can be applied at least twice at VE through V2 growth stages without lowering soybean yield, but applications at VC probably should be avoided.

Preparation of Corncob Grits as a Carrier for Immobilizing Yeast Cells for Ethanol Production

In this study, DEAE-corncobs [delignified corncob grits derivatized with 2-(diethylamino)ethyl chloride hydrochloride (DEAE·HCl)] were prepared as a carrier to immobilize yeast (Saccharomyces cerevisiae) for ethanol production. The immobilized yeast cell reactor produced ethanol under optimized DEAE·HCl derivatization and adsorption conditions between yeast cells and the DEAE-corncobs. When delignified corncob grit (3.0 g) was derivatized with 0.5M DEAE·HCl, the yeast cell suspension (OD600 = 3.0) was adsorbed at >90% of the initial cell OD600. This amount of adsorbed yeast cells was estimated to be 5.36 mg-dry cells/g-DEAE corncobs. The Qmax (the maximum cell adsorption by the carrier) of the DEAE-corncobs was estimated to be 25.1 (mg/g), based on a Languir model biosorption isotherm experiment. When we conducted a batch culture with medium recycling using the immobilized yeast cells, the yeast cells on DEAE-corncobs produced ethanol gradually, according to glucose consumption, without cells detaching from the DEAE-corncobs. We observed under electron microscopy that the yeast cells grew on the surface and in the holes of the DEAEcorncobs. In a future study, DEAE-corncobs and the immobilized yeast cell reactor system will contribute to bioethanol production from biomass hydrolysates.

Digesta passage rates in the Florida manatee (Trichechus manatus latirostris)

The Florida manatee, Trichechus manatus latirostris (Sirenia: Trichechidae), is an herbivorous marine mammal found within coastal areas throughout the state of Florida, which feeds on both fresh and salt water sea grasses. Manatees, like other Sirenians, are a tropical species with little tolerance for water temperatures below 20 degrees C, rely on a relatively poor nutritional food source, and have a low metabolic rate. Although manatees are hindgut fermenting herbivores, they are very efficient at extracting nutrients from the plants on which they feed. Slow passage rates of digesta have been suggested to be a factor in this increased efficiency. Two studies monitored the digesta passage times and mixing of particulate digesta within the manatee digestive tract using MicroGrits colored corncob grit as a fecal marker. Fecal samples were collected subsequently from four manatees in Study 1 and 3 manatees in Study 2, grit pieces removed, counted, and measured. The digesta passage times ranged from 6 and 10 days in Study 1, and 4.3 and 8.3 days in Study 2, supporting data presented in previous studies. When two different colored markers were administered on sequential days, minimal to no mixing was seen in recovered feces, suggesting that the digesta from a given day traveled through the tract as a bolus. Less than 1% of the marker fed was recovered and we hypothesize that perpendicular folds of the large intestine may be the major contributing factor, with pieces being retained and eventually digested. Zoo Biol 26:503-515, 2007. (c) 2007 Wiley-Liss, Inc.

Formulation of filamentous fungi for bioremediation

Mycelia of Marasmiellus troyanus embedded in calcium alginate granules with corn cob grits as a nutritive amendment were viable after one year with refrigeration but inviable when stored at room temperature. With refrigeration, Phanerochaete chrysosporium mycelia and spores embedded in alginate were both viable after one year. At room temperature, spores encapsulated in alginate granules gave good viability while mycelial formulations did not. In all trials, corn cob grits was superior to saw dust for extending shelf life. Corn cob grits-amended granules of both species were able to germinate and grow in both uncontaminated soil and chemical waste-contaminated soil.

European Corn Borer Control, 1997

Abstract This planting was seeded on 25 Jun at the Fruit and Vegetable Research Farm near Geneva, NY, using a tractor-powered two-row seeder planting 8 seeds/ft. Plots consisted of two rows 50 ft long with 3 ft row widths. Each plot was separated by two untreated buffer rows to minimize spray drift. Each treatment was replicated four times in a RCB design with a 20-ft buffer zone between adjacent replications. In this trial, larvae were inoculated in each plot twice, about 24 h pre- and post-spray, respectively. It was necessary to infest snap bean plots with ECB with colonies because exceedingly low levels of natural infestation of beans by this pest in this climate precluded statistical comparisons among 1 treatments. Plants were in varying stages of development (i.e., pre-bloom to pin pod) at the time of larval inoculation, the majority being in late bloom. On 18 Aug, an estimated 595 ECB first instars were placed on 30 ft of each treatment row in each replication. Before the inoculations were initiated, larvae were evenly dispersed in corncob grits. They were then applied evenly over the plants with a Davis Insect Inoculator (Bio-serv, Inc., P.O. Box 450, Frenchtown, NJ 08825). The plant foliage was moistened with water before the inoculations using a backpack sprayer so that the mix of corn cob grits and larvae would adhere to the foliage. On 19 Aug, spray treatments were applied using a CO2 powered tractor mounted six nozzle boom delivering 45 gal water/acre at 40 lbs psi. The second inoculation consisted of about 560 ECB larvae placed on only 15 ft of each treatment row on 20 Aug. Thus, there were portions of each row that received two inoculations (simulating two oviposition periods) while the rest of each row (clearly marked and staked) received only the first inoculation (simulating a single oviposition peak). Plants were inspected for ECB injury and larvae on 8 Sep by pulling out all plants in the 30-ft inoculated sections, thus including plants that were inoculated both once and twice.

Alginate Encapsulation of the White Rot Fungus Phanerochaetechrysosporium

In the laboratory, the white rot fungus Phanerochaetechrysosporium degrades numerous organic pollutants. Lack of aslow-release delivery system to toxic waste sites, for this and other fungi,however, constitutes an important barrier to practical implementation. Inthis study, the use of calcium alginate as an encapsulant for mycelia wasinvestigated; samples were in the form of pellets 1-3 mm in diameter. Whenrefrigerated, alginate-embedded mycelia of P. chrysosporium wereviable for one year, both with and without nutrient supplementation. At roomtemperature, in the absence of nutrient supplementation, viability decreasedsharply within 2 months. Addition of sawdust or corncob grits extended theviability of alginate-embedded mycelia; nevertheless, after 9 months onlyabout 20% of the pellets stored at room temperature yielded fungalgrowth. Spores of P. chrysosporium, embedded in alginate pelletstogether with corncob grits, gave 75% viability after 9 months ofstorage at room temperature. Alginate-embedded mycelia were used in Petriplate toxicity tests with 2,4,6-trinitrotoluene (TNT) and gave more rapid andreproducible results than tests performed with mycelial plugs. Theseexperiments demonstrated the feasibility of encapsulating P.chrysosporium in calcium alginate pellets, thus providing a potentialmethod of delivering white rot fungi to toxic waste sites, as well as fordeveloping a system of standardized toxicity testing in plate assays.

Control of European Corn Borer Larvae and Effect on Spider Mites on Reproductive Stage Field Corn, 1995

Abstract Various pesticides were applied to blister stage (R2 stage) field corn on 28 Aug near North Platte, NE. The treatments were applied with a CO2-charged backpack sprayer through 11002VS flat fan nozzles at 20 psi, in a total volume of 21 gpa. Each treatment was applied to 10 X 35 ft plots and replicated four times in a RCB design. One day prior to application, ~90 neonate ECB larvae were released on each of four plants in the center of each plot. The larvae were mixed in corn cob grit which was applied to the axils of three leaves of each plant. Artificially infested plants were collected 50 DAT, split from root to tassel and evaluated for the presence of ECB caused cavities, their total length and live ECB larvae. The size of TSM and BGM colonies were rated on the underside of the three lowest leaves of each 4 randomly selected plants from the middle of each plot 14 DAT. The rating scale was 0-5: 0 = no mites, 1 = individual mites (0-10 mites), 2 = small colonies (11-100 mites), 3 = large, individual colonies (101-300 mites), 4 = large connected colonies but not completely covering the underside of the leaf (301-1000 mites), 5 = colonies completely covering the underside of the leaf (1001-2000 mites).

Performance of endophyte-free and endophyte-infected tall fescue seedlings in soil infested withCochliobolus sativus

Responses of tall fescue (Festuca arundinacea) seedlings free of or infected with Acremonium coenophialum were determined when exposed to soil infested with Cochliobolus sativus. In a greenhouse pot experiment, germinated seeds of AU Triumph and Kentucky 31 (KY 31) tall fescue were covered with a soil mixture containing corncob grits infested with C. sativus. Emergence, establishment of seedlings, and growth of leaves and shoots were determined weekly for 6 wk. Emergence and growth of KY 31 seedlings were greater than for those of AU Triumph. Plant stand, height, and shoot fresh weight were significantly reduced by C. sativus after 6 wk in plants free of or infected with A. coenophialum compared to noninoculated plants. There was no significant difference in growth parameters between plants free of or infected with A. coenophialum. The data support a neutral interaction between the endophyte and the pathogen.

Sodium polyacrylamide polyacrylate, a gelling agent in diets for cabbage looper, omnivorous looper and western avocado leafroller

AbstractIngredient substitutions for agar or carrageenan in artificial diets for lepidopterous larvae were evaluated. A sodium polyacrylamide polyacrylate gelling agent, Water‐Lock G‐400, was compared with agar for solidifying diets of the cabbage looper, Trichoplusia ni (Hübner), omnivorous looper, Sabulodes aegrotata (Gueneé), and the western avocado leafroller, Amorbia cuneana Walsingham. Water‐Lock G‐400 is considerably less expensive than agar or carrageenan, it does not require heating to gel, and it is made from a dependable supply of agricultural starch.Sabulodes aegrotata pupae from larvae reared on agar were significantly heavier than those reared on Water‐Lock G‐400. However, the remainder of the variables observed (larval survival, developmental times, fecundity, sex ratio and pupal weights for A. cuneana and T. ni) were all independent of diet. Decreasing the total amount of ingredients in a Water‐Lock‐G‐400 diet produced fewer and smaller T. ni pupae than did an agar diet when the larvae were reared using a mass production protocol. However, these lower values were still above acceptable levels for mass production and reduced the cost of diet production by 65%.Further ingredient substitutions impaired larval development (i.e., replacing pinto beans with soy protein or combinations of soy protein and α‐cellulose), while others did not (i.e., excluding pinto beans and reducing water content and replacing pinto beans with α‐ cellulose or corn cob grits). Moisture control by adding corn cob grits to diets increased the yield of pupae, while removing water from diets increased survivorship and the yield of pupae.

Control of European Corn Borer Larvae on Reproductive Stage Field Corn, 1994

Abstract Various pesticides were applied to blister stage (R6 stage) field corn on 9 Aug, near North Platte, NE. The treatments were applied with a CO2-charged backpack sprayer through 8001 flat fan nozzles at 30 psi, in a total volume of 21 gal/acre. Each treatment was applied to 3 by 10 m plots and replicated 4 times in a RCB design. On the day of application, neonate ECB larvae were applied, in corn cob grit, to the axils of 3 leaves of 5 plants in each plot. Artificially infested plants were collected 40 DAT, split from root to tassel and evaluated for the presence of ECB caused cavities, the total length of ECB caused cavities and live ECB larvae. The incidence of lodged plants was determined 48 DAT on 20 consecutive plants from the middle of each of the center 2 rows of each plot. BGM infested leaves were attached to 2 plants in each plot 2 d prior to application. Seven, 14, and 28 DAT the size of spider mite colonies were rated, on a 0-6 scale, on the underside of the 4 lowest leaves of the previously infested plants. These plants were also evaluated for the presence of arthropod predators.

Comparison of alginate and “Pesta” for formulation of Phanerochaete chrysosporium

Alginate and wheat gluten (“Pesta”) matrices were compared for the encapsulation of the white rot fungus Phanerochaete chrysosporium. “Pesta” granules were not successful for formulating P. chrysosporium although control granules made with Alternaria alternata yielded viable fungal colonies; the gluten in wheat flour apparently inhibits growth of the white rot fungus. P. chrysosporium formulated in alginate with corncob grits or sawdust, and stored at room temperature, yielded over 50% viability of encapsulated mycelia after six months. Alginate encapsulation offers a promising technology for the delivery of white rot fungi to toxic waste sites.

Formulating Atoxigenic Aspergillus flavus for Field Release

A procedure was developed to encapsulate mycelia of an atoxigenic strain of Aspergillus flavus in alginate pellets for seeding into agricultural fields in order to reduce aflatoxin contamination via competitive exclusion. Kaolin, a clay filler commonly employed in alginate formulations, was detrimental to pellet performance as measured by spore yield. Corn cob grits, a by-product of the corn industry, was found to be an excellent replacement for kaolin. Of nine nutritive adjuvants tested, wheat gluten improved pellet performance the most, although gluten concentrations above 5% were difficult to process. The best formulation tested consisted of 1% sodium alginate, 5% corn cob grits and 5% wheat gluten. On a 'per gram' basis, this alginate formulation yielded more spores than either A. flavus sclerotia or colonized wheat seed. Pesticides were also tested as adjuvants with potential use for protecting pellets under field conditions. Only one (chloramphenicol) of four tested pesticides (the others were dichloran, rose Bengal and cyfluthrin) reduced pellet sporulation. Formulations with or without pesticide adjuvants retained similar spore yield potential during a 2-year storage at 8 C. However, spore production in stored products lagged behind that of fresh products. At 75% relative humidity (RH), pellet storage stability decreased with increasing temperature from 27 to 42 C. Pellet spore yield at 32 C decreased as RH decreased from 100 to 90%. Sporulation occurred at 90% RH but not at 88% RH. Spore yield varied widely in four field tests, and the cumulative spore yield was inversely correlated (r2= -0.798, P 0.01) with rainfall. The results suggest that alginate pellets may be effective formulations for delivery of atoxigenic A. flavus strains to furrow-irrigated cotton in desert environments, where aflatoxin contamination of cottonseed is most severe.

First Generation European Corn Borer Control, 1993

Abstract Twelve insecticides were evaluated for control of 1st generation ECB larvae. The test plot was planted in a second-year corn field on the UK Spindletop Research Farm in Fayette County on 7 May as a randomized block design with 3 replicates. Individual plots consisted of 2 rows, 24 m long, with 96.5 cm row spacing. Plants within each plot were artificially infested with newly hatched 1st instar ECB. Larvae were mixed with corn cob grits and delivered into the whorls by Bazooka applicator at a rate of 40 larvae per plant on 21 Jun. M-Peril 5G, Pounce 1.5G, and the 4 Lorsban 15G granular formulations were applied in a band over the whorl stage corn using a Noble applicator driven by electric motor and mounted on a high-clearance tractor. Liquid insecticides were applied using a Solo-backpack sprayer at 20 psi and 33 gpa. All treatments were applied 24 Jun. Ten stalks were removed from each plot, split and the numbers of ECB caused cavities recorded on 14 Jul. Data were subjected to ANOVA and treatment means were compared to the control by LSD.