Agronomy and Crop Sciences Commons^™

Inference Space Choices In Combined Mixed Model Analyses Of Discrete Grazing Trials, H A. Fribourg, R W. Thompson, J C. Waller, W L. Sanders

IGC Proceedings (1977-2023)

Grazing trials are limited by financial and logistical constraints that restrict duration and number of treatments to be investigated. Combining data from independent trials may be a feasible way to circumvent these constraints and provide a more meaningful body of information. Datasets were pooled from 12 independent trials conducted during the last 13 springs at 9 locations in 7 USA eastern states (a total of 37 location/ years) to provide combined estimates of steer (Bos taurus) performance on Festuca arundinacea pastures free of or infested with the endophytic fungus Acrenoium coenophialium, and to demonstrate the effectiveness and …

An Expert System To Advise Tasmanian Farmers On Pasture Mixtures And Fodder Crops, Peter Gillard

IGC Proceedings (1977-2023)

In Tasmania, the Department of Primary Industry and Fisheries needed to find a more effective method of informing farmers obout the best pasture and forage species. PASTURBPAK, an expert system, was designed to meet this need. The program offers advice on mixtures of species and lists cultivars that are adapted to the environment, and the need of the farmer and livestock type. Seed merchants have installed the software to make the information available when farmers buy seed. Sales starf can now instantly access the corporate expertise of DPIF, and offer customers printed advice specific to their need. The relevance of …

Comparison Of Two Calibration Procedures For Predicting Leaf Percentages From Forage Sorghums And Pearlmillets Using Near-Infrared Reflectance Spectroscopy, T P. Karnezos, A G. Matches, J W. Keeling

IGC Proceedings (1977-2023)

A rapid method for determining leaf percentage (LP) from forage sorghums (Sorglium bicolor (L.) Moench) and pearlmillets (Pennisetum americaum (L.) Leeke) is reported. Our objective was to develop and compare two near-infrared reflectance spectroscopy (NIRS) calibration methods for predicting LP. Calibration methods developed were: I) leaves assigned a value of 99.99% leaf and 0.01 % stem, and stems a value of 99.99% stem and 0.01% leaf; and 2) ground leaf and stem samples mixed by weight to obtain a range of LP. Samples were scanned using NIRS and calibration equations developed. Equations had coefficients of multiple determination (R2) …

Computer Simulation To Aid The Development, Transfer An Adoption Of Alternative Forage Conservation Systems, C A. Rotz, D R. Buckmaster

IGC Proceedings (1977-2023)

A computer simulation model of forage production, conservation and use was developed to evaluate forage technologies. The model simulates forage losses and quality changes along with the use and costs of machines, structures, labour, fuel, chemicals, etc. Alfalfa and corn produced on the farm arc supplemented with purchased feeds to feed a dairy herd or they are sold. Simulation over many years of weather conditions provides a long-term evaluation of the performance and economics of alternative forage systems. Simulation results provide manufacturers with design-performance constraints which aid the development of new products. Adoption of available forage technology is aided by …

Developing Long-Term Weather Records For Use With Rangeland Management Modelsc, Clayton L. Hanson, J Ross Wight

IGC Proceedings (1977-2023)

The use of natural resource models for research and management of rangeland ecosystems is limited by the unavailability of long-term weather records. This paper identifies sources of weather information for the United States; suggests methods for estimating missing records; and illustrates the use of double-mass curve procedures for evaluating the quality of data sets. Where weather data are limited in ducat ion or unavailable, stochastic weather generation is an option to simulate daily weather records.

Making Models Easy To Use, J Ross Wight, Clayton L. Hanson

IGC Proceedings (1977-2023)

A major limitation to the application of natural resource models to resource management problems is the unavailability of input information and complexity of model operation and output interpretation. These problems can be moderated by using synthetic weather data, algorithms and expert systems to calculate model parameters and input variables and computer programs to simplify development of input data files and interpretation of output results. This paper summarises some of the procedures and techniques that can be used to make models easier to use and more useful as management tools.

Simulation Models As Decision Aids For Management Of Rangeland Ecosystems, J Ross Wight, Clayton L. Hanson

IGC Proceedings (1977-2023)

Rangeland simulation models have been used primarily as research tools to synthesise and organise information and to conceptualise and describe the interacting components of the ecosystem. Their application as decision aids for range management has not been developed. This paper discusses ways simulation models, such as SPUR· (Simulation of Production and Utilisation of Rangelands), can be used to forecast herbage p1oduction and the occurrence of biological windows, enhance monitoring, and predict the impacts of management and climate change on the soil, water, and plant resources including species composition.

Models Of Pasture Production To Aid On-Farm Decision Making In New Zealand, J A. Baars, M D. Rollo

IGC Proceedings (1977-2023)

Two microcomputer-based predictive pasture models, for use in decision making by agricultural consultants and industry, are described. The first model (GRASS) was developed to understand the interactions between environment and management. The second model supplies pasture growth rates for current or predicted weather conditions by adjustment of stored actual average fortnightly pasture growth rates for a wide range of measurement sites. Ways are described in which the models are being used in transfer of technology.

Production Of Dryland Lucerne In The Western And Southern Cape Regions Of South Africa, J M. Van Heerden

IGC Proceedings (1977-2023)

Cutting trials were conducted with lucerne (Medicago sativa) cv. S A Standard under dryland conditions over a period of 8 (1982 to 1989) years at 2 sites, one each in the western (Elsenburg) and southern (Tygerhoek) Cape. The sites differed in soil type and rainfall distribution. Replicated plots were harvested at 3 set frequencies (4·, 6- and 8- weekly). Production was lowest during summer and highest in late spring and increased with decreased harvesting frequency at both sites. These data were used to derive equations for the extrapolation of the seasonal yield. Inputs into the model 11cc average …

Graze Model: Importance Of Simulating Conceptual Grazing Areas Within A Paddock, Otto J. Loewer, L D. Parsch, H D. Scott, C P. West, A L. Goetsch

IGC Proceedings (1977-2023)

The selective grazing logic within the computer simulation model GRAZE was tested to determine if predicted ·results differed appreciably from situations ·where non-selective grazing logic· was used. Results indicated that predictions would_ differ somewhat." The main cause of the differences was determined to be the simulated levels of plant dry matter availability, which were considerably higher when non-selective· grazing was used.

Development Of An Expert System For New Zealand Seasonal-Supply Dairy Farmers, D I. Gray, G A. Lynch, E G. Todd, J C. Lockhart, W J. Parker

IGC Proceedings (1977-2023)

The mechod for developing an expert system for the drying-off decision on seasonal-supply dairy farms is described. The decision-making process ' of 4 expert seasonal-supply dairy farmers and the consultancy process used by 2 New Zealand Dairy Board Consulting Officers were identified in a series e>f interviews. This information ,was used to develop 2 models; one of expertise and the other of user requirements. These models form the basis of an expert system to improve the decision-making ability of. New Zealand seasonal-supply dairy farmers.

Rehabilitation On Public Rangelands In Idaho, Usa: A Change In Emphasis From Grass Monocultures, Mike Pellant, Stephen B. Monsen

IGC Proceedings (1977-2023)

Since the 1940s the Bureau of Land Management has reseeded 485 830 ha of public rangelands in southern Idaho. Introduced wheatgrasses were seeded on most rehabilitation projects, often resulting in monoculture plant communities. Introduced wheatgrasses were relatively inexpensive to seed, established well, excluded weedy annuals and provided additional livestock forage. Concern about extensive shrubland losses after wildfires prompted BLM managers to begin reseeding native shrubs in the early 1980s. Use of different herbaceous plants on rehabilitation projects is increasing. Seed mixtures now include up to 10 species (grass, forb and shrubs) that, when established, meet multiple use resource objectives.

Micro-Computer Version Of The Database On Feed Commodities Derived From Pastures And Green Crops, H T. Ostrowski-Meissner

IGC Proceedings (1977-2023)

The subunit of the national feed database devoted specifically to feeds derived from grasslands and green crops is presented. This collection of chemical and nutritional data is the result of 20 years of data collection from analyses conducted from 62 laboratories Australia-wide, The data entries are classified according to each Australian state and laboratory which provided the analytical and nutritional characteristics of fodder. Each entry is classified according to the International Feed Numbering (IFN) system as maintained by the International Network of Feed Information Centres (INFIC), The data in the collection as presented in the paper are an integral part …

A Computer Model For Determining When To Start Spring Grazing, Dennis R. Buckmaster, Warren J. Parker

IGC Proceedings (1977-2023)

A simple computer model is presented for determining the earliest grazing date after winter freezing. The model also illustrates principles of rotational grazing management and projects when forage should be conserved during the spring. Inputs to the model include initial herbage cover, herbage growth rate, herbage quality, a post•grazing residual dry matter target, a harvest set•aside threshold, and a description of the grazing animals.

Comparison Of Methods For Assessing Productivity Of Native Pastures In Queensland, K A. Day, G M. Mckeon, D M. Orr

IGC Proceedings (1977-2023)

The relationship between seasonal climatic conditions and observed seasonal pasture growth was examined for 3 native pasture sites in south-east Queensland for periods of up to 5 years. Nine indices of seasonal climatic conditions were considered. Across sites, between year differences in observed growth were best accounted for by the average daily ratio of calculated transpiration and vapour pressure deficit, This index accounted for 83% of the between year variation in observed growl h.

Application Of Neural Networks To The Extraction Of Various Types Of Grasslands In Japan Using Landsat Thematic Mapper Data, Mikinori Tsuiki, Shigeo Takahashi, Toshiki Oku

IGC Proceedings (1977-2023)

A neural network was applied to the extraction of various types of grasslands using Landsat Thematic Mapper (TM) data. Training fields contained 12 classes (water, paddy field, farmland, sands and rocks, urban area, coniferous forest, deciduous forest, golf course, Sasa­type grassland, Miscanthus type grassland, meadow before culling and meadow after cutting). Classification performance using the neural network was 99.4%, which was 2.4% higher than that obtained using the maximum likelihood method. For all types of grasslands, classification performance was 99.8%. The results of the classification area obtained using the neural network and the maximum likelihood method resembled each other. …

Use Of A Simple Model Of Continuous And Rotational Grazing To Compare Herbage Consumption, Simon J.R Woodward, G `C Wake, D G. Mccall, A B. Pleasants

IGC Proceedings (1977-2023)

A simple mathematical model (a linear dynamical system) was constructed to predict herbage consumption by grazing animals. This model was used to compare 3 grazing methods over a range of stocking rates at low pasture mass. The grazing methods compared were: continuous grazing (CTS), rotational grazing with equal time intervals (BQ), and rotational grazing where the time of shift was optimal for maximising intake (OPT). The rotational methods were the simplest possible, the land being subdivided into 2 fields, each of which was grazed once. The order of grazing the fields was also considered. The model predicts (I) that at …

Pasture Plant Identification In The Western Queensland Arid Zone, J A. Milson, I F. Beale, J A. Reynolds, J J. Bushwell, D Phelps

IGC Proceedings (1977-2023)

Since plant species composition is an important indicator of the health or condition of pastures and therefore the land, a first step for graziers interested in conserving the total range resource is to understand vegetation species and thus be able to identify them and to recognise species changes. This project is aimed at producing and distributing colour leaflets of the major native and problem plant species (including woody weeds) in the four major community types in western Queensland. The number of colour leaflels for the series totals 60. The number of species represented is about 230. These leaflets are dislributed …

Farm Monitoring, A Way To Improve Performance On Sheep And Beef Farms, R W. Webby, G W. Sheath

IGC Proceedings (1977-2023)

A programme that centres on monitoring the performance of sheep and beef farms is being used to encourage farmers to make decisions based on objective measurements, Monitor farmers are supported by their farming peers in groups that include extension and science personnel. Key biological performance indicators such as animal numbers, weights; weight gains, pasture production; and financial returns from meat and wool are monitored. Farmers are encouraged to be in a position to use this information and identify opportunities. Processors of sheep and beef products are demanding the production of livestock to tighter specifications. Close monitoring by farmers will be …

Use Of A Model To Investigate The Profitability Of Fertilizer Application, T.J M. Johnston, D G. Mccall, P R. Marshall

IGC Proceedings (1977-2023)

Use of a model to investigate the payback to alternative phosphate (P) fertiliser programmes is described. Input for the model is fertiliser history (kg P/ho/year) over 5-15 years. A site fertility index is established by summing discounted P applications. The index is related to relative pasture yield (annual yield/non P limited yield) for a soil type. The economics of P use are evaluated by scaling current gross margin/ha for changes in relative pasture yield and subtracting fertiliser costs. The model provides the decision maker with yearly cashflow information and a I 0-year net present value (NPV) analysis of the relative …

Cover Crop Utilization Across Nebraska And Implications For Cropland Lease Arrangements In 2024, Jim Jansen, Jeffrey Stokes

Cornhusker Economics

The Nebraska Farm Real Estate Market Survey and Report 2023-2024 provides insight on recent trends in the market value of land and cash rental across the state. Each year, the special feature section covers topics on new or emerging issues related to the agricultural land industry in Nebraska. These topics reflect the interest expressed by panel members and readership of the Nebraska Farm Real Estate Market Highlights Reports. The special feature section in 2024 focuses on trends and considerations for cover crops across Nebraska and implications on lease arrangements.

Findings from the 2022 Census of Agriculture in Table 1 provide …

Association Mapping Of Important Agronomic Traits In Mucuna Pruriens (L.) Dc., Patrush Lepcha, Mahesh Shekhar, Leelambika Murugesan, Mahammad Jaheer, Ratan Chopra, Vikas Belamkar, Narayana Sathyanarayana

Department of Agronomy and Horticulture: Faculty Publications

Background The tropical legume Mucuna pruriens (L.) DC. can meet three agricultural needs: low-cost protein, highvalue medicines, and green manure or cover crops. But like other underutilized crops, it needs more modern breeding resources. Identifying marker-trait associations (MTAs) can facilitate marker-assisted breeding and crop improvement. Recent studies have demonstrated the feasibility of identifying MTAs using a small number of accessions (< 100). We have characterized a panel of 70 M. pruriens accessions across two consecutive years and performed association analysis for 16 phenotypic traits related to seed (seed length, seed width, seed thickness, seed yield per plant, hundred seed weight); pod (pod length, pod width, number of pods …

How Advection Affects The Surface Energy Balance And Its Closure At An Irrigated Alfalfa Field, Tianxin Wang, Joseph Alfieri, Kanishka Mallick, Ariane Arias-Ortiz, Martha Anderson, Joshua B. Fisher, Manuela Girotto, Daphne Szutu, Joseph Verfaillie, Dennis Baldocchi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Orbiting around the non-closure problem in eddy covariance, a new generation of high-resolution thermal imagery has revealed that advection may be more common than previously expected. To investigate this, we conducted an extensive study over an irrigated alfalfa field that experienced heat and moisture advection. Over the course of five analysis periods (37 days total), multiple tower arrays and profile measurements were deployed to measure the horizontal advection and vertical heat flux divergence. Latent heat flux (λE) measured at the anchor tower showed an enhancement (i.e., increase) due to both local and non-local processes. Locally, as a result of the …

Pastoral Grasses And Legumes As Potential Host Plants For Fall Armyworm Spodoptera Frugiperda (J.E. Smith) Development, Saleh Adnan, Holly Cattermole, Kim Saligari, Helen Spafford

Grain and Other Field Crops Research Articles

The fall armyworm, Spodopterafrugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is a highly polyphagous, migratory pest native to the tropical and subtropical region of Americas. Grass crops particularly corn have been most heavily impacted since S. frugiperda invaded Australia in 2020. In northern Western Australia, S. frugiperda is primarily a problem in dry season (May to October) crops when there are abundant host plants available in monocultures. During the wet season (November to April) it is not known what host plants may support larval growth and development. Accordingly, this present study undertook a no-choice feeding bioassay to assess larval and pupal …

What Is The Best Fit For Electric Weed Control In Australia?, Miranda J. Slaven, Catherine Borger

Experimental Summaries - Plant Research

Electric weed control is a non-chemical weed management alternative that will apply to a range of agricultural systems. The current project assessed electric weed control via the continuous electrode-plant contact method (using a Zasso™ XPower).

A wide range of field trials in 2022 and 2023 investigated weed control efficiency, suitability of electric weed control for fence line control of glyphosate-resistant annual ryegrass (Lolium rigidum Gaud.), use for crop topping, fire risk, damage to the soil biota, or use for inter-row weed control in vineyards or lupin crops. Broadleaf weeds were controlled more effectively than grass weeds with electric weed …

Effect Of Biochar Composition And Paclobutrazol Concentration On Growth And Yield Of G1 Medians Cultivar Potato Seeds In Jatinangor Medium Plain, Jajang Sauman Hamdani, Zahira Salsabilla Idris Putri, Wawan Sutari

Jurnal Kultivasi

Potato seed production in the medium plain is necessary to avoid environmental damage and the limited area of potato seed production in the high plain. The effort to increase the production of G1 potato seeds on the medium plain is the evaluation of the biochar composition and concentration of paclobutrazol that can increase the production G1 potato seeds cv Medians in the medium plain of Jatinangor. The research was conducted from August to December 2022 at the Ciparanje Experimental Field. Jatinangor. Faculty of Agriculture. Universitas Padjadjaran. The experiment used a Factorial Randomized Block Design (RBD). The first factor was the …

Evaluation Of Padjadjaran Maize Hybrids In Intercropping System With Soybeans Under Albasia Shade, Yuyun Yuwariah, Audi Razaqa Soendajana, Fiky Yulianto Wicaksono, Dedi Ruswandi

Jurnal Kultivasi

Intercropping between maize and soybean has been known to be widely practiced by subsistence farmers. Some farmers do intercropping in production forests and there are no scientific data about it. The aims of the study were to evaluate the growth and yield of Padjadjaran maize hybrids and to estimate Land Equivalent Ratio, Competitive Ratio, and Stress Tolerance Index under intercropping of maize and soybeans under the shade of Albasia. The experiment was carried out from January to June 2021 in Tanjungsari, Sumedang Regency with an altitude of 818 m above sea level. The experiment used a Randomized Block Design (RBD) …

Growth Response Of Tomatoes To Application Of Bacterial-Coated Npk Fertilizer In A Pot Experiment, Reginawanti Hindersah, Ruhnayati Kaffah, Ayu Siti Aisyah, Mieke Rochimi Setiawati, Mahfud Arifin

Jurnal Kultivasi

Nitrogen-fixer and phosphate-solubilizer bacteria increase the chemical-fertilizer efficiency and soil health. Bacterial-coated NPK fertilizer is a novel approach for intensifying biofertilizer application in vegetable production. The study aimed to observe the compatibility between two Azotobacter species and two Bacillus species, their population on two formulations of bacterial-coated NPK fertilizer (BCN), and the effect of BCN dose on growth, N and P content, and their uptake in tomato shoots. The compatibility test was performed using the streak method. The population of Azotobacter and Bacillus were counted for two formulations of NPK fertilizer coated by solid biofertilizer (5% and 10%) and zeolite …

Growth Improvement Of Immature Quinine By Applying Coffee Husk Compost And Biofertilizer, Yudithia Maxiselly, Dinda Rachmatis Sa'adah, Mira Ariyanti, Muhammad Khais Prayoga, Heri Syahrian Khomaeni

Jurnal Kultivasi

The growth of immature Cinchona ledgeriana can be optimized by applying fertilizers to fill the nutritional needs of plants. Nutrients can be provided through the help of microorganisms derived from organic fertilizers and biofertilizers. This study aims to evaluate the effect of applying coffee husk compost and biofertilizer consortium on the growth of immature quinine plants. This research was conducted from November 2023 – January 2024 at Gambung Tea and Cinchona Research Center, Pasir Jambu District, Bandung Regency, West Java. The research used a randomized block design with four replications and six treatments, namely control (Urea 17 g.plant-1 + SP36 …

Genetic Parameters Of Yield Component And Yield In M1 Rice (Oryza Sativa L.) Generation Irradiated With Gamma-Ray, Agus Riyanto, Eka Oktaviani, Nur Kholida Wulansari, Totok Agung Dwi Haryanto

Jurnal Kultivasi

High-yielding varieties are the primary determinant of the success of increasing Indonesia's rice production. Plant breeding for new high-yielding varieties is possible through mutation induction and selecting desired traits. The effectiveness and efficiency of selection require comprehensive genetic parameters. This study aimed to study the genetic diversity, heritability, genetic advance, and relationship between yield components and yield in the M1 generation of mutant rice irradiated with gamma ray. This research used a factorial randomized complete block design, involving gamma irradiation doses of 100 Gy, 150 Gy, and 200 Gy, as the first factor; and the second factor was the rice …