Agronomy and Crop Sciences Commons^™

Effects Of Microwave Treatment On Drying And Respiration In Cut Alfalfa, S A. Seif, D A. Holt, V L. Lechtenberg, R J. Vetter

IGC Proceedings (1977-2023)

After forage crops are cut mechanically, they usually undergo some degree of natural drying before being stored or further processed. During early stages of drying, plant respiration continues. Treatments or management practices that hasten drying and reduce postharvest respiration are desirable, because they minimize quantity and quality losses. Our objective was to determine the effects of brief microwave treatment on subsequent natural drying rate and respiration of alfalfa (Medicago sativa L. ). Duplicate samples of field grown Apollo alfalfa were subjected to focused microwave energy (2,450 MHz) generated at 0.25, 0.50, or 1.0 kilowatt of power for 3, 6, …

Effect Of Formic Acid- Formaldehyde Treatments On The Nitrogenous Constituents In Annual Ryegrass Silage, M L. Fishman, F Mchan, D Burdick

IGC Proceedings (1977-2023)

Prevention of proteolysis during ensiling is important in preserving the nutritive value of silage. Hence, the mechanism by which silage protein is protected against degradation was studied in wilted annual ryegrass (Lolium multiflorium Lam.) silage pretreated with formic acid, formaldehyde, and a formic acid-formaldehyde mixture. Raw-wilted ryegrass, control ryegrass silage, and treated ryegrass silage were extracted and fractionated under conditions previously found to maximize yield of nitrogenous constituents and minimize proteolysis during the extraction of fresh grass. Extractions were by boric acid-borate buffer at pH 8.0 with and without detergent (1 % sodium dodecyl sulfate). Sodium metabisulfite, an antioxidant, was …

Addition Of Lactobacillus Sp. To Aid The Fermentation Of Alfalfa, Corn, Sorghum, And Wheat Forages, N J. Moon, L O. Ely

IGC Proceedings (1977-2023)

As preservation of forage by ensiling has increased, so has the use of additives to enhance acid fermentation. Many of the fermentation aids currently on the market contain microflora to insure a lactic acid fermentation. The objectives of this study were to characterize the basic patterns of fermentation in a variety of crops and to evaluate the effects of adding selected microflora to forages to enhance the fermentation. Four crops were ensiled in each of three seasons. Alfalfa was harvested at 20 %-40 % bloom, second cut; wheat was cut in the early dough stage; corn was cut in the …

Interrelationships Between Pattern Of Fermentation During Ensilage And Initial Crop Composition, J M. Wilkinson, P F. Chapman, R J. Wilkins, R F. Wilson

IGC Proceedings (1977-2023)

Relationships between crop composition and silage composition were examined for 231 silages made at the Grassland Research Institute from 1968 to 1978 without additives. A test was made of the model of Weissbach et al. (1974) in which silage characteristics were related to the percentage of dry matter in the crop (OM) and the ratio of sugar (Z) to buffering capacity (PK). Although these factors accounted for significant variance, the percentage accounted for was low at 36 % for lactic acid (percentage of total acids), 26 % for Flieg's score, 22 % for ammonia N (percentage of total N), and …

Effect Of Delayed Sealing During Ensiling On Fermentation And Dry-Matter Loss, N Takano, Y Masaoka, T Manda

IGC Proceedings (1977-2023)

Two experiments were carried out from 1976 to 1980 to ascertain the effect of delayed sealing of silo on fermentation, dry· matter (DM) loss, digestibility, and silage intake. The effect of delayed sealing (up to 72 hours) of grass and corn silage was tested in laboratory silos on fermentation quality with storage temperatures at 15°C and 30°C, moisture content from 49% to 85 % , water-soluble carbohydrate (WSC) content ranging from 11.1 % to 17.5%, and with and without an addition of 0.25% formic acid. In all cases, delayed sealing resulted in poor-quality silage with high pH values and low …

Improving Hay Quality By Ammoniation, K J. Moore, V L. Lechtenberg, K S. Hendrix, J M. Hertel

IGC Proceedings (1977-2023)

Experiments were conducted to determine the effect of hay ammoniation on hay consumption and weight gain by steers when the hay was fed unsupplemented and supplemented with energy and protein. Mature orchardgrass (Dacrylis glomerata L.) hay was baled in early June 1979 and treated with anhydrous ammonia at 30 g/kg of hay. Seven weeks after treatment the hay was uncovered and allowed to aerate for 3 days. It was then fed to weanling steer calves weighing approximately 225 kg each. Similar hay baled from the same field but not ammoniated was fed to separate groups of steers. Both the treated …

Evaluations Of Low-Quality Roughages And Fibrous Cereal Grains Treated With Various Chemicals, G C. Fahey Jr, L L. Berger, M I. Mora, P J. Van Der Aar

IGC Proceedings (1977-2023)

Large improvements in the feeding value of low-quality roughages have resulted from treatment of them with various chemicals. Chemical treatment of grains may also be a potentially useful practice. The research reported here was designed (1) to determine how Chelating Metal Caustic Swelling (CMCS), a nontoxic, alkaline, aqueous reagent, compares with sodium hydroxide (NaOH) in enhancing in-vitro cellulose digestion (IVCD) of cornstalks (CS) (Zea mays) and soybean residues (SBR) (G!),cine max.), and (2) to evaluate the effects of NaOH and CMCS treatments of fibrous grains using in-situ techniques. CMCS or 7.5% NaOH solutions were added to CS or SBR at …

Effect Of Solvent Treatments On Intake And Digestibility Of Corn Stover, D M. Schaefer, M R. Ladisch, C H. Noller, V L. Lechtenberg

IGC Proceedings (1977-2023)

Treatment of crop residues with low levels of sodium hydroxide has been shown to improve organic-matter digestibility and animal performance. One objective of these experiments was to evaluate the effects of three treatments -water, sodium hydrox­ide, and chelating metal cellulose-swelling solution-on solubilization of cell-wall components in corn (Zea m£rys) stover. The two latter treatments were balanced for level of sodium hydroxide application, which was .3 .2 % of stover dry matter. The second objective was to determine the effects of these treatments on in-vitro and in-vivo digestibility as well as on consumption of corn stover. Twelve growing ram lambs were …

Factors Causing Greater In-Vitro Than In-Vivo Digestibility Of Sodium Hydroxide - Treated Roughages, L L. Berger, T J. Klopfenstein, R A. Britton

IGC Proceedings (1977-2023)

Research on sodium hydroxide (NaOH) treatment oflow-quality roughages generally indicates that in-vivo digestion is lower than in-vitro digestion. The purpose of this research was to identify factors that may cause less of the potentially digestible fiber to be digested in vivo than in vitro. Corn (Zea mays) cobs were raised to 60% moisture and treated to contain 0%, 2.5%, 5.0%, 7.5 % , and 10.0% NaOH. Lambs were fed diets containing 80% cobs and 20% supplement, giving a complete mixed diet con· taining 0%, 2.0%, 4.0%, 6.0%, and 8.0% NaOH. Five abomasally cannulated lambs were assigned to a 5 x …

Relationship Between Silage Quality And 15 N-Nitrate Reduction During Ensilage, K Ataku, M Horiguchi, T Matsumoto

IGC Proceedings (1977-2023)

Nitrate in forage has been proven to occasionally poison ruminants. Our recent studies, however, have shown that a high con­centration of nitrate inhibits butyric acid fermentation to the advantage of the silage quality. This work was undertaken to see the relationship between silage quality and the pattern of nitrate reduction during ensilage.

Exploring Regenerative Vegetable Systems On The Central Coast Of California, Una S. O'Connell

Master's Theses

As climate change and current agricultural practices place pressure on the long term sustainability and resilience of food production systems, there is growing interest in whether existing agricultural systems can adapt to maintain productivity while improving environmental outcomes.

This study evaluated the effects of regenerative versus standard organic vegetable production systems on yield, insect communities, and weed suppression across three field trials conducted on California's Central Coast. In addition, I collected baseline soil health data for all trials. Trials 1 and 2 were carried out at the Cal Poly San Luis Obispo Organic Farm using cabbage and broccoli as cash …

Spatial Variation In Soil Quality Across Selected Fruit Tree Plantations In Bacnotan, La Union, Philippines, Jay Mark G. Cortado, Roberto G. Visco, Jenielyn T. Padrones, Pastor L. Malabrigo Jr

The Philippine Agricultural Scientist

Sustaining soil quality on any plantation is critical to increasing productivity and responsible land use. However, spatial variation in soil quality across fruit tree plantations under existing field and management conditions remains insufficiently documented. This study aimed to assess the soil quality of monocropped plantations of banana, calamansi, coffee, and rambutan in northern Luzon, Philippines, evaluate the extent of degradation or improvement relative to a reference forest using the Soil Quality Index (SQI) approach, and identify the soil indicators that significantly influence soil quality in these plantations. The objectives were to determine which fruit tree plantations could enhance soil quality …

Crop Performance Of Aromatic Basmati Rice Grown In Tidal Lands In Indonesia [Research Note], Riza Adrianoor Saputra, Indra Jatmika Liran, Yulia Padma Sari

The Philippine Agricultural Scientist

Rice production in Banjar Regency has declined in recent years due to land-limiting factors, particularly the suboptimal conditions of tidal wetlands. Therefore, improving cultivation techniques for new superior varieties such as Aromatic Basmati is essential to enhance productivity on marginal lands. This study aimed to determine the best combination of seedling number per planting hole and seedling age, as well as to evaluate the effect of each factor on the growth and yield of Aromatic Basmati rice cultivated on tidal land. The experiment was conducted for 4 mo (August to December 2020) in the experimental paddy fields of the Agricultural …

Marker-Assisted Identification Of Hybrids In Polyembryonic ‘Carabao’ Mango (Mangifera Indica L.) Breeding In The Philippines, John Edward L. Felipe, Kyla Andrea G. Mendoza, Benjamin Christian J. Esguerra, Carolyn E. Alcasid, Gino R. Hernandez, Eureka Teresa M. Ocampo

The Philippine Agricultural Scientist

Varietal improvement of the Philippine ‘Carabao’ mango (Mangifera indica L.) through conventional breeding is constrained by polyembryony, which makes it difficult to distinguish zygotic hybrids from nucellar seedlings at early developmental stages. This study evaluated the utility of simple sequence repeat (SSR) markers for early and accurate identification of hybrids in polyembryonic ‘Carabao’ mango crosses. Genomic DNA was isolated from 24 parental accessions and 61 putative hybrid seedlings using a modified CTAB protocol that yielded DNA suitable for PCR-based marker analysis. Eighty-one SSR markers were screened across 29 parental combinations, of which 64 markers (79.0%) were polymorphic in at …

Growth And Yield Of Rice (Oryza Sativa L.) Under Different Irrigation Methods In Transplanted And Direct-Seeded Systems, Wang Guirui, Crisanta S. Bueno

The Philippine Agricultural Scientist

In the face of climate change and socioeconomic transformation, there is an urgent need to save energy and enhance rice production. Direct-seeded rice (DSR) is a viable alternative to transplanted rice due to reduced water and labor requirements, potentially achieving comparable or higher yields with reduced inputs. This study was conducted in the 2025 dry and wet seasons in Los Baños, Philippines, using a 2-factorial randomized complete block design with 4 replications. The first factor was the 2 rice varieties NSIC Rc 506 (Tubigan 41, V1) and NSIC Rc 160 (Tubigan 14, V2), and the second factor was cultural management, …

Can Generative Ai Make Farming Decisions? Current Status And Future Pathways: A Case Study In Row Crop Production With Chatgpt, Nipuna Chamara, Yufeng Ge, Joe Luck, Yu Pan, Saleh Taghvaeian, Cory Walters, Christopher Proctor, Daran Rudnick, Daren Redfearn

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The agricultural decision-making process is experience-based, knowledge-dependent, time-sensitive, complex, and driven by historical data. Planting, fertilization, irrigation, and chemigation are key categories in farm decision-making, and currently there is no one-shot decision-support tool that covers all these activities. Generative Artificial Intelligence (AI) models are more advanced than traditional machine learning and deep learning models. These models have been trained on vast amounts of data from the internet, allowing them to accept unstructured data in various forms and generate human-like text, solutions to problems, and scenario predictions. Given this capability, we became interested in exploring the potential of generative AI in …

Effects Of Irrigation And Nitrogen Management On Yield And Leaching Risk In Organic And Conventional Broccoli Fields, Shane Egerstrom

Master's Theses

Under regulatory pressures to reduce groundwater contamination by nitrate from fertilizer, such as those posed by the Central Coast Regional Water Quality Control Board’s Agricultural Order 4.0, a need exists to better understand interactions between irrigation and nitrogen (N) management. To increase N use efficiency (NUE), growers are encouraged to account for additional sources of N in their management plans, such as irrigation water N and preplant soil N. The availability of these N sources for plant uptake and how it is affected by other management conditions is not yet well documented. We conducted 6 field trials, 3 organic and …

Evaluation Of Ultraviolet-C Light For Control Of Mites And Western Tarnished Plant Bug In Strawberry & Interactive Lethal Effects Of Common Strawberry Fungicides And Adjuvants On Phytoseiulus Persimilis, Colin T. Koubek

Master's Theses

California strawberry production relies heavily on chemical pesticides to manage arthropod pests and diseases, but pesticide resistance, regulatory pressure, and the need to conserve biological control agents have increased interest in alternative pest management tools. This thesis evaluated ultraviolet-C (UV-C) light as a nonchemical management tool for key strawberry arthropod pests and assessed the compatibility of common strawberry fungicides and adjuvants with the predatory mite Phytoseiulus persimilis Athias-Henriot. The first objective was to determine the ovicidal and lethal effects of UV-C light on Lygus hesperus Knight eggs and nymphs. Laboratory and field ovicide assays were conducted using UV-C doses relevant …

Arkansas Corn And Grain Sorghum Research Studies 2025, Jason Kelley, Travis Faske

Arkansas Agricultural Experiment Station Research Series

The 2025 edition of the Arkansas Corn and Grain Sorghum Research Studies Series includes research results on topics pertaining to corn and grain sorghum production, including weed, disease, nematode, and insect management; economics; irrigation; agronomics; soil fertility; drone use; research verification program results; and numerous miscellaneous topics. Our objective is to capture and broadly distribute the results of research projects funded by the Arkansas Corn and Grain Sorghum Board. The intended audience includes producers and their advisors, current investigators, and future researchers. The Series serves as a citable archive of research results. The reports inform and guide our long-term recommendations, …

Fate Of Nitrogen Applied To Grassland In Animal Wastes, M Sherwood

IGC Proceedings (1977-2023)

The experiment was designed to determine the effects of land spreading of animal manures on the nutrient content of surface runoff water and infiltrating soil water. This report deals only with nitrogen (N) and attempts to quantify the losses through runoff, leaching, and volatilization of ammonia (NH3) as well as N uptake in the grass over a 3-year period. Experimental plots sited on grassland, on two soil types (a moderately drained loam and an impermeable gley), were equipped to collect surface runoff water. Ceramic probes were installed in each plot at 15-, 30-, 60-, and 100-cm depths to extract in­filtrating …

Annual Losses Of Ammonia From A Grazed Pasture Fertilized With Urea, V R. Catchpoole, L A. Harper, R J.K Keyers

IGC Proceedings (1977-2023)

Nitrogen-balance studies have shown losses of applied nitrogen (N) from grazed pastures in southeastern Queensland. Losses as high as 80% have been observed from urea N broadcast at 376 kg N/ha/yr over 8 years on a Setaria sp1uu:elata cv. Nandi pasture. Management techniques aimed at reducing this loss and thereby increasing the efficiency of use of N by pastures cannot be devised until the pathways of loss are known. The objective of this research was to estimate the annual ammonia (NH3) loss by convective transport from a urea-fertilized pasture at Samford Pasture Research Station in southeastern Queensland. Urea was broadcast …

Nitrogen Losses From Urine-Affected Areas Of A New Zealand Pasture, Under Contrasting Seasonal Conditions, P R. Ball, D R. Keeney

IGC Proceedings (1977-2023)

Grazing ruminants aggregate large quantities of forage nitrogen (N) into urine patches. Pasture plots treated with urine N were studied to assess its fate under contrasting seasonal conditions: cool-moist (representing winter-spring); warm-moist (late spring-early summer), and warm-dry (late summer-autumn). A permanent ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) sward on free-draining alluvial soil was studied. 'freatments were replicated in randomized blocks. Urine N was applied at 30 or 60 g N/m2• Relevant measurements were then continued until treatment differences disappeared. Apparent N balances for urine treatments were compiled. Fixation by white clover was always greatly reduced in …

Effects Of Grazing Management On Seasonal Variation In Nitrogen Fixation, J L. Brock, J H. Hoglund, R H. Fletcher

IGC Proceedings (1977-2023)

Using the acetylene reduction assay, field studies in recent years have investigated the variation in N fixation in grazed systems, and some of the principles involved in the interaction with available soil N have been described. This experiment ex­tends this work to include the effect of grazing management on the factors influencing N fixation. Two self-contained sheep-grazed units, one a 10-paddock rotationally grazed system and the other set stocked, were estab­lished on a high-fertility ryegrass-white clover pasture, with a basic stocking rate of 22 sheep/ha. Over the 1975-1978 period, both units were monitored for pasture growth, N fixation, and associated …

Symbiotic Nitrogen Fixation Of Alfalfa, Birdsfoot Trefoil, And Red Clover, G H. Heichel, C P. Vance, D K. Barnes

IGC Proceedings (1977-2023)

Forage legumes such as alfalfa (Medicago sativa L.), birdsfoot trefoil (Lotus comiculatus L.), and red clover (Trifolium pratense L.), grown in crop rotations, can provide an inexpensive source of nitrogen (N) to succeeding crops. Few quantitative measurements of seasonal patterns of N fixation in managed communities of perennial forage legumes have been undertaken, chiefly because of the lack of satisfactory methods. Therefore, there is little knowledge of how N fixation varies with crop development, yielding ability, and weather patterns. Quantitative measurements of N fixation are important in choosing the appropriate legume for use in a crop rotation and for …

Photosynthate Supply And Nitrogen Fixation In Forage Legumes, P M. Murphy

IGC Proceedings (1977-2023)

Photosynthate supply is known to limit nitrogen fixation in legumes, and the resulting shortfall in energy supply necessary for maximum crop production may be aggravated by the energy-wasteful process of hydrogen (H2) evolution by the legume N2 fixing system. There is less information available on these aspects of the nitrogen-fixing process in forage legumes, such as white clover (Trifolium repens). The objectives of the present work were to determine how N2(C2H2) fixation and H2 production are in­fluenced by carbohydrate supply in forage legumes.

Plants were grown under controlled environmental conditions, and nodule energy supply was varied by adjusting …

Selection Of Rhizobium Strains For Enhanced Dinitrogen Fixation In Forage Legume Production, C Hagedorn, W E. Knight

IGC Proceedings (1977-2023)

A set of procedures for the selection of Rhizobium strains for enhanced dinitrogen fixation in forage legumes is presented. Although forage legumes are among the most efficient members of the Leguminosae regarding biological nitrogen fixation (BNF), they are generally neither productive nor persistent without effective nodulation by appropriate rhizobia. The following methods define a selection and evaluation process to obtain appropriate Rhizobium strains. These include (1) regional survey of the production area, (2) strain collection and soil analyses, (3) strain characterization, (4) strain selection and manipulation, and (5) field evaluation of strains. The initial procedure is to survey the region …

Interactions Between Grasses And Rhizosphere Nitrogen-Fixing Bacteria, M H. Gaskins, D H. Hubbell, S L. Albrecht

IGC Proceedings (1977-2023)

Sorghum and Digitaria cultivars grown in soil or nutrient solutions were inoculated with a strain of Azospirillum in short-term greenhouse experiments. Carbon compounds lost by roots in solution culture experiments were determined in order to estimate the quantity of energy substrates that might be obtained by rhizosphere organisms from growing plants. Other plants were treated with plant growth hormones, and responses were compared to those of plants treated with killed Azospirillum cells. The similarity of the responses suggests that growth-hormone production by the inoculant organism, rather than nitrogen (N) fixa­tion, is responsible for part or all of the increase in …

Simple Computer Simulation Models For Forage-Management Applications, G W. Fick, D Onstad

IGC Proceedings (1977-2023)

Dynamic computer simulation models of forage growth can be useful in interpreting physical and biological limitations on production and in designing management systems for testing in the field. The explanatory detail of such models makes them both more reliable and more expensive to use than simple empirical formulations. Simple simulation models reduce the expense. They can also serve as reference points for designing, evaluating, or selecting more complex versions and thus provide a more ra­tional basis for using models in grassland research and management. Our objectives were to develop and to test a simple dynamic simulation model of alfalfa (Medicago …

Energy Flow And Conversion Efficiency In Grazing Grassland, T Akiyama, S Takahashi, M Shiyomi, T Okubo

IGC Proceedings (1977-2023)

Measurable energy storage on grassland ecosystems was examined for 5 years at the Fujinita site under the same rotation pro­gram with two grazing intensities. Daily global solar radiation and photosynthetic active radiation were measured as the energy sources in the ecosystem. Primary production by pasture plants and amount grazed by cattle were estimated by the biomass dif­ferences inside and outside of protection cages. For the estimation of energy produced or stored by plants or cattle, calorific values were examined for dominant plant species at the Fujinita site. Seasonal changes in digestibility were investigated to ascertain the energy of herbage digested …

A System Approach To Swedish Ley Production, J F. Angus, A Kornher, B.W R. Torssell

IGC Proceedings (1977-2023)

A simulation model for estimating yield of leys from standard meteorological observations is described. It is based on an S-shaped growth curve also accounting for phasic development and regrowth depression. Effects of temperature, radiation, and soil moisture are accounted for by a growth index. Soil moisture is simulated with a standard water budget. The parameters in the model were estimated by comparing measured with calculated growth. The model then predicted final harvest with reasonable accuracy, but with underestimate of early season growth, presumably due to mobilization of car­bohydrate from storage organs. Observed ley yields from 49 Swedish parishes (1961-1978) were …