Agronomy and Crop Sciences Commons^™

Over-Summering Ecology Of The Wheat Curl Mite (Aceria Tosichella Keifer), Anthony J. Mcmechan

Department of Entomology: Dissertations, Theses, and Student Research

The wheat-mite-virus complex is a consistent and significant threat to winter wheat production in the western Great Plains. This complex consists of three viruses (Wheat streak mosaic virus, Triticum mosaic virus, and Wheat mosaic virus that are transmitted by the wheat curl mite (Aceria tosichella Keifer). Yield impacts from this complex are typically associated with the presence of volunteer wheat that emerges prior to harvest as a result of hail occurring during the heading stages of wheat in early summer. Historical literature on pre-harvest germination has been primarily focused on accelerating breeding programs; however, critical gaps in knowledge exist on …

Characterization Of Echinochloa Spp. In Arkansas, Hussain Tahir

Graduate Theses and Dissertations

Echinochloa species are the most problematic grass weeds in rice and soybean production throughout the southern United States. The species under this genus has high intra- and interspecific variability, with many ecotypes, observed within a species. This study was conducted to: i) characterize the morphology and phenology of Echinochloa accessions from Arkansas in a common garden; ii) verify the species identity of these accessions based on their morphological traits, and iii) evaluate the dormancy characteristics of Echinochloa accessions. Junglerice (E. colona) was identified as the most common species, comprising about 78% of the accessions collected, with barnyardgrass (E. crus-galli) and …

Cover Crop Mixture Diversity And Function, Angela Florence

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The objective of this study was to evaluate the effect of cover crop mixture diversity on cover crop function. Specifically, this study evaluated the effect of cover crop species and functional richness on aboveground biomass productivity, weed suppression, soil nutrient retention, soil microbial community characteristics, and performance stability. Twenty to forty cover crop treatments were replicated three to four times at eleven sites across southeastern Nebraska using a pool of eighteen species representing three cover crop species each from six pre-defined functional groups: cool-season grasses, cool-season legumes, cool-season brassicas, warm-season grasses, warm-season legumes, and warm-season broadleaves. Each species was planted …

Biology, Gene Flow, And Management Of Glyphosate-Resistant Common Waterhemp (Amaranthus Rudis Sauer) In Nebraska, Debalin Sarangi

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Common waterhemp is the most troublesome weed in the midwestern United States. Growers from Nebraska reported failure to control common waterhemp following sequential applications of glyphosate in glyphosate-tolerant corn and soybean, which led to moderate to severe yield loss; justifying the need to confirm resistance and study the biology and management of common waterhemp. The objectives of this research were: 1) to confirm the presence of glyphosate-resistant (GR) common waterhemp biotypes in Nebraska and to evaluate their sensitivity to herbicides belonging to alternative sites-of-action; 2) to evaluate the response of common waterhemp to water stress; 3) to quantify pollen-mediated gene …

Respons Tanaman Jagung (Zea Mays L.) Toleran Herbisida Akibat Pemberian Berbagai Dosis Herbisida Ipa Glifosat 486 G/L, Agus Wahyudin, Fiky Yulianto Wicaksono, D. F. Sari

Jurnal Kultivasi

Jagung merupakan salah satu serealia yang strategis di Indonesia. Jagung mempunyai peluang untuk dikembangkan karena fungsinya sebagai bahan pangan utama dan sebagai sumber bahan pakan ternak. Penggunaan tanaman jagung PRG toleran herbisida glifosat diharapkan dapat mengurangi penurunan hasil tanaman jagung. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian berbagai dosis herbisida glifosat terhadap pertumbuhan dan hasil tanaman jagung (Zea mays L.) PRG toleran herbisida glifosat. Penelitian dilaksanakan di Kebun Percobaan Ciparanje Fakultas Pertanian Universitas Padjadjaran, kecamatan Jatinangor, kabupaten Sumedang, Jawa Barat pada bulan Desember 2014 hingga April 2015. Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok (RAK) dengan 8 perlakuan dan …

Plant Functional Trait And Hyperspectral Reflectance Responses To Comp B Exposure: Efficacy Of Plants As Landmine Detectors, Paul V. Manley Ii

Theses and Dissertations

At least 110 million landmines have been planted since the 1970s in about 70 nations, many of which remain in place today. Some risk of detection may be mitigated using currently available remote sensing techniques when vegetation is present. My study focused on using plants as phytosensors to detect buried explosives. I exposed three species representing different functional types (Cyperus esculentus (sedge), Ulmus alata (tree), Vitis labrusca (vine)) to 500 mg kg^-1 of Composition B (Comp B; 60/40 mixture of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT)), a commonly used explosive mixture, and measured functional traits and reflectance over …

Use Of Hppd-Inhibiting Herbicides For Control Of Common Weeds In Arkansas And Current Status Of Herbicide-Resistance Among Echinochloa Populations In Arkansas, Clay Starkey

Graduate Theses and Dissertations

Herbicide-resistant weeds in Arkansas cause problems for growers. Up-to-date information and new technologies can help plan mitigation strategies to slow resistant weeds. The objectives of this research were to provide a ‘snapshot’ of herbicide-resistant Echinochloa spp. in rice producing counties, determine how much resistance has spread across the state, and understand the effectiveness of 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides for control of glyphosate-resistant (GR) Palmer amaranth relative to commercial standards currently labeled in soybean. To assess the prevalence of Echinochloa spp. resistance, 82 samples were collected from 23 rice producing counties in 2010. The samples were tested for resistance to commonly …

Canola: A Modern Crop For A Modern Era, Kenneth J. Roché

Doctor of Plant Health Program: Dissertations and Student Research

The University of Nebraska-Lincoln Doctor of Plant Health program is a professional doctorate program with a comprehensive approach to plants and agriculture. The program emphasizes a broad interdisciplinary education across all plant-related disciplines, practical learning, research, and experience through internships. For my final required internship, I worked as a senior agricultural research intern with Research Designed for Agriculture (RD4AG) in Montana. RD4AG is a contract research organization based in Yuma, AZ with over thirty-years of experience. During my three month internship at RD4AG in Montana, a large portion of my responsibilities centered on managing regulated canola trials that were undertaken …

Enhancing The Effectiveness Of Biological Control Programs Of Invasive Species By Utilizing An Integrated Pest Management Approach, Invasive Species Advisory Committee

National Invasive Species Council

Conclusion

Biological control has been shown on many occasions to be the most cost-effective invasive species management tool available. However, integrating biological control projects with the full breadth of other integrated pest management (IPM) tools, expanding post-re- lease monitoring to maximize efficacy, adaptive management, and incorporating new and innovative ecological, and genetic technologies may provide private and public land managers greater opportunities for long-term success in suppression of established invasive species.

Pengaruh Pemberian Zat Retardan Terhadap Pertumbuhan Dan Hasil Ubi Pada Dua Kultivar Kentang (Solanum Tuberosum L.) Di Dataran Medium, Sumadi, Erni Suminar, Murgayanti, Anne Nuraini

Jurnal Kultivasi

Tujuan dari kegiatan penelitian ini adalah untuk mendapatkan informasi mengenai kulti-var kentang dan jenis serta konsentrasi zat retardan yang dapat mendukung pertumbuhan dan perkembangan serta kuantitas dan kualitas hasil ubi bibit kentang di dataran medium. Metode penelitian yang digunakan adalah Rancangan Petak terpisah. Perlakuan terdiri dari petak utama yaitu kultivar yaitu kultivar Nadia dan Granola, dan anak petak yaitu jenis dan konsentrasi zat retardan dengan penggunaan paklobutrazol ( 0; 40; 120 mg L-1 ) atau coumarin (45; 90; 135 mg L-1). Hasil percobaan menun-jukkan bahwa jenis kultivar dan zat retardan berpengaruh terhadap pertumbuhan dan per-kembangan bibit kentang. Terjadi interaksi pada …

Pengaruh Keberadaan Gulma (Ageratum Conyzoides Dan Boreria Alata) Terhadap Pertumbuhan Dan Hasil Tiga Ukuran Varietas Kedelai (Glycine Max L. Merr) Pada Percobaan Pot Bertingkat, Abdul Karim Kilkoda, Tati Nurmala, Dedi Widayat

Jurnal Kultivasi

Percobaan dilaksanakan di rumah kaca Fakultas Pertanian Universitas Padjadjaran, Jati-nangor, Kabupaten Sumedang, Jawa Barat. Tujuan dari penelitian ini adalah untuk menguji eksudat akar yang terdapat pada gulma Ageratum conyzoides dan Borreria alata terhadap pertumbuhan dan hasil tanaman kedelai. Percobaan dilakukan mulai dari bulan Oktober 2014 sampai dengan bulan Desember 2014 dengan menggunakan rancangan acak kelompok pola faktorial. Faktor perlakuan pertama adalah jenis gulma terdiri dari 3 taraf antara lain gulma A. Conyzoides, gulma B. alata dan tanpa gulma (kontrol). Perlakuan kedua adalah ukuran benih varietas kedelai yang terdiri dari 3 taraf. Total kombinasi perlakuan adalah 9 kombinasi perlakuan, dengan 3 …

Pengaruh Dosis Herbisida Glifosat Terhadap Gulma, Pertumbuhan, Dan Hasil Tiga Kultivar Kedelai (Glycine Max (L.) Pada Sistem Tanpa Olah Tanah (Tot), Dedi Widayat, R. Ganilda Yustisiyanika

Jurnal Kultivasi

Penelitian ini bertujuan untuk mengetahui pengaruh interaksi antara dosis herbisida Glifosat dan kultivar kedelai terhadap gulma, pertum-buhan, dan hasil tanaman kedelai. Percobaan dilakukan di Kebun Percobaan Saung Meeting Ciparanje Universitas Padjadjaran Jatinangor, Kabupaten Sumedang. Rancangan percobaan yang digunakan adalah rancangan acak kelompok pola faktorial yang terdiri dari dua faktor dan diulang 3 kali. Faktor yang pertama adalah kultivar kedelai yang tediri dari tiga yaitu kultivar Tidar, Burangrang, dan Slamet. Faktor yang kedua dosis herbisida glifosat yang terdiri dari 3 taraf yaitu 1,5l/ha, 3l/ha, dan 4,5l/ha. Kombinasi perlakuan kultivar dan dosis herbisida glifosat tidak memberikan pengaruh interaksi terhadap bobot kering gulma …

Assessing Multiple-Herbicide Resistance In A 2,4-D Resistant Waterhemp (Amaranthus Tuberculatus) Biotype From Nebraska: Student Research, Roberto Crespo

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

A waterhemp biotype was recently reported resistant to 2,4-D in Nebraska. In addition to the repeated use of 2,4-D, atrazine and imazathapyr were reported to be frequently used to control broadleaf weeds. Greenhouse experiments were conducted to confirm 2,4-D resistance and test for resistance to growth regulator herbicides and other herbicide modes-of-action (MoA). A single dose-response experiment showed reduced sensitivity in all three waterhemp biotypes to atrazine, imazethapyr and lactofen; therefore, they were generally considered resistant to those three herbicide MoA. None of the biotypes contained the Ser264 target-site mutation. Since the ametryn dose-response experiment resulted in all susceptible biotypes, …

Weed Dynamics During Transition To Conservation Agriculture In Western Kenya Maize Production, Judith A. Odhiambo, Urszula Norton, Dennis Ashilenje, Emmanuel C. Omondi, Jay B. Norton

Agricultural and Environmental Sciences Faculty Research

Weed competition is a significant problem in maize (Zea mays, L.) production in Sub-Saharan Africa. Better understanding of weed management and costs in maize intercropped with beans (Phaseolus vulgaris, L.) during transition to conservation agricultural systems is needed. Changes in weed population and maize growth were assessed for a period of three years at Bungoma where crops are grown twice per year and at Trans-Nzoia where crops are grown once per year. Treatments included three tillage practices: minimum (MT), no-till (NT) and conventional (CT) applied to three cropping systems: continuous maize/bean intercropping (TYPICAL), maize/bean intercropping with relayed mucuna after bean …

Herbisida Campuran Imazapic 262,5 G.L-1 Dan Imazapir 87,5 G.L-1 Sebagai Pengendali Gulma Umum Pada Budidaya Tanaman Tebu (Saccharum Officinarum L.), Uum Umiyati, Denny Kurniadie, A. F. Pratama

Jurnal Kultivasi

Tebu adalah tanaman yang menghasilkan bahan pemanis berupa gula pasir.Hasil gula pasir dapat menurun akibat kompetisi gulma. Pengendalian menggunakan herbisida dapat menekan gulma dan meningkatkan pertum-buhan tanaman tebu. Percobaan ini bertujuan untuk mendapatkan dosis aplikasi herbisida campuran Imazapic 262,5 g.L-1 dan Imazapir 87,5 g.L-1 yang terbaik dalam mengendalikan gulma umum di lahan budidaya tebu. Perco-baan dilakukan di PG. Rajawali, Cirebon, Jawa Barat pada bulan Maret - Mei 2014. Percobaan menggunakan Rancangan Acak Kelompok Sederhana yang terdiri dari tujuh perlakuan dan empat ulangan. Perlakuan terdiri dari A) herbisida campuran Imazapic dan Imazapir dengan dosis 0,75 l.ha-1, B) herbisida campuran Imazapic dan …

Historical Common Names Of Great Plains Plants, With Scientific Names Index. Volume I: Common Names, Elaine Nowick

Zea E-Books Collection

Containing thousands of entries of both vernacular and scientific names of Great Plains plants, the literature that informs this exhaustive listing spans nearly 300 years. Author Elaine Nowick has drawn from sources as diverse as Linnaeus, Lewis and Clark, and local university extension publications to compile the gamut of practical, and often fanciful, common plant names used over the years. Each common name is accompanied by a definitive scientific name with references and authority information. Interspersed with scientifically-correct botanical line drawings, the entries are written in standard ICBN format, making this a useful volume for scholars as well as lay …

Historical Common Names Of Great Plains Plants, With Scientific Names Index. Volume Ii: Scientific Names Index, Elaine Nowick

Zea E-Books Collection

Containing thousands of entries of both vernacular and scientific names of Great Plains plants, the literature that informs this exhaustive listing spans nearly 300 years. Author Elaine Nowick has drawn from sources as diverse as Linnaeus, Lewis and Clark, and local university extension publications to compile the gamut of practical, and often fanciful, common plant names used over the years. Each common name is accompanied by a definitive scientific name with references and authority information. Interspersed with scientifically-correct botanical line drawings, the entries are written in standard ICBN format, making this a useful volume for scholars as well as lay …

Biology And Control Of Glyphosate-Resistant Giant Ragweed, Simranpreet Kaur

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Giant ragweed is a troublesome, early emerging, summer annual weed found throughout the eastern and midwestern corn and soybean growing regions of the United States. Since the emergence of giant ragweed varies at different locations, our first objective was to determine the emergence pattern of giant ragweed in Nebraska and how spring tillage influences emergence. Results of a two-year study suggested that giant ragweed emerged from late March until mid-June, with the majority of emergence ceasing by early May. Spring tillage could be used as an alternative method for managing glyphosate resistant giant ragweed.

Water stress can affect the growth …

Productivity And Biological Nitrogen Fixation Of Different Species Of Vetches (Vicia Spp.) Under The Rainfed Conditions Of West Asia, Ali Abd El Moneim, Mohan C. Saxena

IGC Proceedings (1977-2023)

The low rainfall areas of West Asia are characterized by pastoral production system primarily based on small ruminants (sheep and goats). Rangelands serve as the main source of feed. With increasing population, the demand for livestock products has increased. As a consequence, the stocking rates have soared, increasing the pressure on rangelands. Rangeland degradation has therefore been increasing threatening the sustainability of livestock production system and the livelihood of the people dependent on it. Production of additional feed is essential to reduce the pressure on rangelands. Vetches (Vicia spp.) are endemic in the area and can be potential source …

Livestock Production From Grasslands With Improved Management Compared To Traditional Management, Florian Leiber

IGC Proceedings (1977-2023)

The value of traditional versus improved management systems for grassland is discussed. The set target is the persistence of the ecological, economic and social multifunctionality of grasslands and the increase of food output from these areas without increasing parallel requirements for arable crop or energy inputs. Based on the fact that historically traditional systems were stable and sustainable in many cases, while severe damage is faced nowadays, it is argued that lot of improvement should be based on the acknowledgment of successful traditional practises. The challenge might rather be to define improvement as a contemporary development of traditional techniques. The …

Potential Of Forages In Crop Diversification And Crop Rotation, Martin H. Entz, Joanne Thiessen Martens

IGC Proceedings (1977-2023)

Redesign of agricultural systems according to ecological principles has been proposed for the development of sustainable systems. We review a wide variety of ecologically-based crop production practices that focus on forage crops in farming systems and discuss their potential role in enhancing the profitability, environmental sustainability and resilience. Crop-livestock systems that most closely mimic natural systems through appropriate integration of diverse components appear to offer the greatest potential benefits. These systems are more energy efficient and combine high productivity with low ecological footprint. Greater understanding of ecological relationships within crop-livestock systems are required to purposefully and proactively redesign agricultural systems …

Forage Seed Quality: Dormancy, Standards And Quarantine, John G. Hampton

IGC Proceedings (1977-2023)

There are many dimensions to the concept of seed quality. Viable seed which will not germinate when provided with all the requirements for germination is dormant. Forage grasses mostly exhibit non-deep physiological dormancy (PD), while physical dormancy (PY) is common in forage legumes where imbibition is prevented by the seed coat’s impermeability to water (hard seed). Methods for breaking PD and PY to allow germination testing and/or crop establishment are discussed.

In the seed industry seed quality standards are an important feature of quality assurance and may apply for seed production contracts, seed certification, seed sale and seed importing. Standards …

Quality Seed Production And Effective Marketing Systems For Development Of Grasslands, M. Philip Rolston

IGC Proceedings (1977-2023)

Seed quality is defined as (i) maintaining genetic purity using seed certification principles (generation system; isolation; previous cropping history); (ii) achieving high levels of physical purity (especially low weed seed levels) by in field weed control and seed cleaning; (iii) achieving high levels of seed germination at harvest and maintaining germination through the seed supply chain. Seed production systems must not only produce high quality seed but also achieve economic seed yields. Seed crops have to be profitable (by being high yielding) to justify the investment of time and input costs to achieve quality. This in turn requires supporting research …

Scouting Benefits And Developing Innovations In Temperate Grassland To Sustainable Agriculture Production, Walter Ayala, Ethel Barrios, Ignacio Macedo, Jorge Sawchik, José A. Terra

IGC Proceedings (1977-2023)

Agricultural intensification raises concern about land use and future effects to natural resources. The world demand for grain, meat and forest products is increasing constantly. Changes are occurring at large scale, being a compromise for policy makers to contribute to identify opportunities to readdress the productive scenario. There is available technology to reduce impacts, without restricting necessarily productivity. Grasslands provide a large series of economical and ecological benefits to the agricultural systems, being the literature exhaustive in examples. Ley-farming and cover crops technologies are good examples of environmentally sound soil management practices. The society is also worried about an improper …

Evergraze: A Partnership Between Researchers, Farmers And Advisors To Deliver Effective Grassland Management, Warwick B. Badgery, Kate Sargeant, Michael A. Friend, Scott Glyde, Paul Sanford, Ralph Behrendt, Meredith L. Mitchell, Sean Murphy, Angela Avery

IGC Proceedings (1977-2023)

The profitable and sustainable management of livestock production from grassland systems is challenging and it can be difficult to develop a research structure that addresses farmer’s needs and has acceptable rigour and on-ground impact. This paper describes the attributes of research, development and extension (RD&E) programs that are required for a successful partnership between researchers, farmers and advisors. Insights are provided from the EverGraze program that designed, tested and implemented farming systems based on perennial pastures across southern Australia. With this project farmers and advisors were involved in setting research direction, designing experiments, providing strategic guidance over the management of …

Ecologically And Socially Sustainable Livestock Development In Marginal Areas, Ilse Köhler-Rollefson

IGC Proceedings (1977-2023)

“Marginal areas” are perceived as difficult and unproductive landscapes, always under the threat of drought, desertification and poverty. Yet, both dryland and high altitude marginal areas have an extraordinary output of livestock products; in the efficiency of producing human-edible protein they far surpass more fertile areas. This productivity under adverse climatic conditions rests on sophisticated strategies and social institutions developed by pastoral communities to deal with variability in the availability of resources. It depends on the use of animal genetic resources that are adapted to make best use of local vegetation and can cope with seasonal variations in availability. Livestock …

Valuing Variability--New Perspectives On Climate Resilient Dryland Development, Saverio Kratli

IGC Proceedings (1977-2023)

Valuing Variability is a challenge to the view of the drylands as naturally vulnerable to food insecurity and poverty. It argues that improving agricultural productivity in dryland environments is possible by working with climatic uncertainty rather than seeking to control it – a view that runs contrary to decades of development practice in arid and semi-arid lands.

Participatory And Holistic Approaches With Grassland Farmers And Development Of Policies, Alain Peeters

IGC Proceedings (1977-2023)

The world is changing rapidly. Grassland farmers and ruminant livestock breeders will have to adapt to these changing environmental, social and economic conditions. Research can help them at the condition that linear ‘top-down’ technology transfer methods are abandoned for the benefit of participatory and holistic approaches. These approaches classified in the generic term of ‘Farming System Research’ consider farmers as real research partners, and they merge farmer’s and scientist’s ideas with those of other stakeholder types. They combine scientist’s and farmer’s knowledge for creating fast innovations, easily adopted by farmers since farmers themselves contribute to their design and their development. …

Sustainable Grasslands: Resolving Management Options For Livelihood And Environmental Benefits, David R. Kemp, Warwick B. Badgery, David L. Michalk

IGC Proceedings (1977-2023)

To help solve the major issues of improving livelihoods and environmental services, grassland research needs to be evaluated within the context of relevant farm systems. Treatments need to show that they not only have significant effects but that they have effects that are meaningful in the context of the relevant farm system. Research often defines an optimum criterion for management that is a single point, but that is difficult to achieve in practice, especially when there are several components in a grassland system that need to be optimised. It is argued that an appropriate criterion for optimising management is a …

Climate Change Impact And Adaptation In Temperate Grassland And Livestock Industries, Afshin Ghahramani, Andrew D. Moore

IGC Proceedings (1977-2023)

Climate is projected to have negative impact on temperate grassland and livestock productions across the globe. Moderately elevated atmospheric CO₂ in the near future is expected to increase plant photosynthetic rates but this is likely to be limited by soil nitrogen deficits. However, in Australia at least it is unlikely that positive effect of elevated CO₂ on plant production be able to offset the negative impacts of climate change. Currently there is a considerable gap between actual and achievable production and profit in Australian grazing systems and many management and genetic improvements for climate adaptation would operate by …