Agronomy and Crop Sciences Commons^™

Genetic Resources And Precise Gene Editing For Targeted Improvement Of Barley Abiotic Stress Tolerance, Sakura Karunarathne, Esther Walker, Darshan Sharma, Chengdao Li, Yong Han

Grain and Other Field Crops Research Articles

Abiotic stresses, predominately drought, heat, salinity, cold, and waterlogging, adversely affect cereal crops. They limit barley production worldwide and cause huge economic losses. In barley, functional genes under various stresses have been identified over the years and genetic improvement to stress tolerance has taken a new turn with the introduction of modern gene-editing platforms. In particular, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) is a robust and versatile tool for precise mutation creation and trait improvement. In this review, we highlight the stress-affected regions and the corresponding economic losses among the main barley producers. We collate about …

Protecting Wa Crops Issue 31 - July 2023, Department Of Primary Industries And Regional Development, Western Australia

Protecting WA Crops

Protecting WA Crops Issue 31 - July 2023 contents:

• New project to reduce Rhizoctonia impact in low and medium rainfall zones
• Meet Crop Protection team member – Dr Ahmed Saad

Pestfacts Wa Issue 09 - July 2023, Alan Lord, Christiaan Valentine, Kithsiri W. Jayasena, Andrea Hills, Geoff J. Thomas, Ciara Beard, Cindy L. Webster

PestFacts WA

PestFacts WA Issue 9 - July 2023 contents:

• Native budworm are active early
• Powdery mildew
• Slime mould

Evaluating Drill Interseeded Cover Crop Establishment And Nitrogen Impact In Irrigated Corn, Victor De Sousa Ferreira

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

The adoption of cover crops as a strategy to improve soil health and cropping systems sustainability is on the rise in the United States. PRE herbicides with soil residual activity are widely applied in corn production systems to prevent early season weed development, crop-weed competition, and yield loss. When preemergence herbicides are applied in the field, the active ingredients remain in the soil rhizosphere for a period of time, killing weed seedlings as they emerge. However, PRE herbicides can also impact the establishment of interseeded cover crops. Greenhouse bioassay was conducted to evaluate the preemergence herbicide carry-over potential to interseeded …

Pestfacts Wa Issue 11 - July 2023, Alan Lord

PestFacts WA

PestFacts WA Issue 11 - July 2023 contents:

• Native budworm activity update

Pestfacts Wa Issue 10 - July 2023, Svetlana Micic, Cindy L. Webster, Benjamin S. Congdon, Kylie Chambers

PestFacts WA

PestFacts WA Issue 10 - July 2023 contents:

• Russian wheat aphid
• Turnip yellows virus detected in flying green peach aphids and in canola
• Bacterial blight, Septoria avenae blotch and leaf rust are appearing in oats

Maintaining Grassland Plant Diversity While Controlling Woody Plant Encroachment, James Stubbendieck, Kay L. Kottas, S. J. Tunnell, S. J. Palazzolo

IGC Proceedings (1977-2023)

The tallgrass prairie region of the United States is a fragmented grassland ecosystem. Much of the 1 to 2% of the remaining prairie is being degraded by invading woody plants, which frequently results in a shift from grassland to woodland. Smooth sumac (Rhus glabra L.), a shrub native to the region, can rapidly increase in density and become dominant in the plant community. Prescribed fire alone is not a constraint to this resprouting species (Stubbendieck et al., 2003). Herbicides are useful tools for managing woody plants in grasslands, but the negative response of desirable plants to herbicides is …

Do Species And Functional Diversity Indices Reflect Changes In Grazing Regimes And Climatic Conditions In Northeastern Spain?, F. De Bello, J. Leps, M. T. Sebastià

IGC Proceedings (1977-2023)

Understanding the mechanisms that maintain biodiversity in various ecosystems enables the development of management practices that prevent degradation (Canals & Sebastia, 2000). Each diversity index reflects some compositional properties and could be influenced differently by stress and disturbance factors (Magurran, 2004). In this study, we aim to reveal 1) which management practices and environmental factors affect biodiversity in rangelands of northeastern Spain and 2) the relationship between species diversity and functional diversity (SD and FD).

Impact Of Grazing Regimes On Mean Sward Height: Implications For The Management Of Bird Habitats In Agricultural Landscapes, M. Tichit, D. Durant, E. Kernéïs

IGC Proceedings (1977-2023)

Grazing in wet grasslands is a key process to manage foraging and nesting habitats for waders. Grazing has positive and negative effects related to the importance of sward conditions for these species and to nest-trampling by cattle. For settlement and nesting, lapwings need a short sward ( ≤ 10cm; see Durant et al., this congress). However, when lapwings settle in early spring, grasslands seldom are grazed yet, due to low soil carrying capacity. We studied the effect of autumn and winter grazing regimes on sward structure in early spring, and the effect of grazing regime in early spring on …

Soil Carbon Sequestration Under Three Years Of No-Till Forage Cropping Systems, D. H. Min, J. D. Deyoung, Richard Leep

IGC Proceedings (1977-2023)

The effects of reduced tillage on soil organic carbon (SOC) are generally well established (Chan et al., 2002; Cabardella & Elliott, 1992). The effects of different crops are also somewhat understood (Drinkwater et al., 1998). However, many of these studies are done in the laboratory to study the effects of crop residues on SOC. Many forage-based systems have very little crop residue returned to the field. What residue does return is often in the form of manure or compost, which is usually broken down much more rapidly than most crop residues. The objective of this study is to …

Number And Viability Of Seeds Recovered From Faeces Of Ruminant Animals, Alaba O. Jolaosho, Olufemi S. Onifade, O. M. Arigbede, Jimoh A. Olanite, T. O. Akinola

IGC Proceedings (1977-2023)

Ruminants play a significant role in the dissemination of plant seeds as a result of ingested seeds during grazing on pasture escaping digestion that are voided with the faeces and returned to the seed bank (Russi et al., 1992).

Population Changes Of Invasive Annuals In California Annual And Perennial Grasslands, Richard King

IGC Proceedings (1977-2023)

Some non-native annual forbs and grasses can be invasive in California's annual grassland region. Taeniatherum caput-medusae (L.) Nevski and Centaurea solstitialis L. can spread quickly, become nearly monospecific stands, and reduce carrying capacity for livestock and wildlife. Centaurea also can be toxic to horses. Lathyrus hirsutus L. is less invasive, but the seed is toxic to various livestock. Since 1991, the author has raised beef cattle on 16 ha of predominantly annual grassland where these 3 species occur, and a family member has raised cattle on approximately 40 ha of adjacent property. Surface soils in this hilly land are …

The Effect Of Sheep Grazing At Two Stocking Rates On The Seedling Recruitment Of Grassland Forbs, Johannes Isselstein, Markus Kowarschik, S. Bonn, M. Hofmann

IGC Proceedings (1977-2023)

Limitations for seedling recruitment are major constraints to maintain and enhance plant species diversity in productive grasslands (Bakker & Berendse 1999). Grass sward condition plus species-specific requirements for germination and survival determine the recruitment success. Therefore, a field experiment investigated the establishment of oversown seeds from wildflower forbs in relation to grass sward management.

A Basis For Designing Policies To Optimize Soil Carbon Sequestration In Southeastern Us Grasslands, Joel R. Brown, D. L. Faulkner

IGC Proceedings (1977-2023)

Increasing the amount of carbon (C) stored in terrestrial ecosystems is an important part of most national greenhouse gas (GHG) management strategies. Among the policy and program options available to achieve increased C sequestration, improved management of grasslands offers an attractive option to both reduce atmospheric concentrations of C and enhance environmental co-benefits (soil quality, water quality, food and fibre production, and wildlife habitat). In the United States, incentives for applying improved land management practices come primarily via federal government conservation programs administered by the United States Department of Agriculture (USDA). While private sector markets offer opportunities to increase the …

The Nature Of Sequestered Carbon In Different Irish Mineral Soils, C. M. Byrne, D. Fay, J. A. Ferreira, M. H. B. Hayes

IGC Proceedings (1977-2023)

Humic substances (HS) provide the major sinks for carbon (C) in soils. Although HS have a degree of resistance to microbial degradation, they are degraded in time. Humin, the HS component in association with the soil mineral colloids, has greatest resistance to degradation. To understand the extent to which soil can be a sink for C it is important to know the soil mineralogy, and to be aware of aspects of the structures of the humic components. Enhanced biological oxidation occurs in soils in long term cultivation. Its effects can be observed by comparing the amounts and compositions of the …

Conversion Of Native Grassland To Coniferous Forests Decreased Stocks Of Soil Organic Carbon And Microbial Biomass, Lidong Li, Elnaz Hosseiniaghdam, Rhae A. Drijber, Elizabeth Jeske, Tala Awada, J. Hiller, Michael Kaiser

Department of Agronomy and Horticulture: Faculty Publications

Aims Encroachment of woody species into grasslands is a global phenomenon that affects ecosystem services, including soil organic carbon (SOC) storage and microbial community structure. We determined stocks of SOC and soil microbial biomass as affected by conversion of grasslands to coniferous forests.

Methods We examined SOC and soil δ¹³C signatures under three vegetation covers: native grasslands, eastern redcedar (Juniperus virginiana), and ponderosa pine (Pinus ponderosa), at six soil depths (0 − 10, 10 − 30, 30 − 100, 100 − 170, 170 − 240, 240 − 300 cm). Fatty acid methyl esters (FAMEs) …

Classim: A Relational Database Driven Crop Model Interface, Dennis Timlin, David Fleisher, Maura Maura, Kirsten Paff, Wenguang Sun, Sahila Beegum, Sanai Li, Zhuangji Wang, Vangimalla Reddy

Department of Agronomy and Horticulture: Faculty Publications

Crop models are valuable tools for examining the interactions of cultivar characteristics, environment, and management practices, and how they affect crop growth and development. The difficulty in finding all the data needed to set up a simulation can often deter potential users from utilizing a crop model. Model interfaces are necessary to make these complex tools accessible to end-users who may lack the expertise needed to work with the models directly, but who would benefit from the information generated by the models. As crop models vary in terms of input and output structures, there is no one universally compatible interface, …

Tillage, Green Manuring And Crop Residue Management Impacts On Crop Productivity, Potassium Use Efficiency And Potassium Fractions Under Rice-Wheat System, Sandeep Sharma, Pritpal Singh, Hayssam M. Ali, Manzer Hussain Siddiqui, Javed Iqbal

Department of Agronomy and Horticulture: Faculty Publications

The conventional crop production practices including intensive tillage and open field crop residue burning in world’ largest rice-wheat system (RWS) are adversely affecting crop productivity besides deteriorating natural resources and ecosystems’ sustainability. In order to improve system productivity, potassium (K) use efficiency and apparent K balance, adoption of conservation tillage in a RWS with residue management is considered highly effective. We therefore, studied the effect of wheat straw retention and green manure (GM) in rice (main plot treatment), and tillage and rice residue management in subsequent wheat (sub-plot treatments) on crop productivity, K use efficiency and its transformation amongst different …

The Effect Of Dairy Cow Genotype On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara

IGC Proceedings (1977-2023)

A three-year systems comparison study was undertaken to see if progressively increasing the genetic potential for milk production of the dairy cow is desirable within pastoral based systems of spring milk production (Kennedy et al., 2002). The production data was inputted into the Moorepark Dairy System Model (MDSM) (Shalloo et al., 2004) to describe the economic, biological and production efficiency of each system. Output was then used to model whole farm greenhouse gas (GHG) emissions (Lovett et al., in press) from the nine systems studied (three concentrate levels by three genotype levels). Only the genotype effects are …

Methane Of Animal Origin In Cattle Fed High Or Low Tannin Sorghum Silage, T. T. Berchielli, S. G. Oliveira, M. P. Pedreira, O. Primavesi, M. A. Lima, R. Frighetto

IGC Proceedings (1977-2023)

The harmful or beneficial effects associated with the presence of tannin in plants depends on its concentration and form. One of these beneficial effects is the reduction of the production of methane in the rumen (Woodward et al., 2001). This study financed by FAPESP aimed to evaluat the effect of diets containing low or high tannin sorghum silage supplements on dry matter intake (DMI) and methane production in cattle.

Field Measurements Of Ruminal Methane Of Cattle Grazing Tropical Grasses, M. P. Pedreira, O. Primavesi, M. A. Lima, R. Frighetto, T. T. Berchielli

IGC Proceedings (1977-2023)

Ruminal methane production represents energy losses from ingested feed that should be utilised to maintain body weight or to generate products. Quantitatively, daily methane production varies according to amount and quality of ingested dry matter (DM), as well as physiological status of the animal.

Hedgerow Systems And Livestock In Philippine Grasslands: Ghg Emissions, D. B. Magcale-Macandog, E. Abucay, R. G. Visco, R. N. Miole, E. L. Abas, G. M. Comajig, A. D. Calub

IGC Proceedings (1977-2023)

Hedgerow systems are widely adopted in the smallholder farms in the sloping grassland areas of Claveria, Mindanao, Philippines. The system is effective in addressing soil erosion problems and in conserving the topsoil. Gmelina arborea and Eucalyptus deglupta are two fast-growing timber species that are planted in hedgerow systems while maize is planted in the alley areas in between the hedgerows. Livestock holdings are widespread in Claveria, with 74% of the households having livestock. Cattle and carabao are the most common livestock in smallholder farms providing draught power for land preparation and transportation. In hedgerow systems, fodder tree leaves and crop …

The Effect Of Soil Type And Climate On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara

IGC Proceedings (1977-2023)

The ability of spring calving dairy farmers to exploit herbage production can be limited by soil type and climatic conditions. Previous work, using the Moorepark Dairy System Model (MDSM) (Shalloo et al., 2004) demonstrated differences in terms of biological and production efficiency for two contrasting sites. This study models whole farm greenhouse gas (GHG) emissions (Lovett et al., in press) from two dairy systems, the Moorepark Standard System (MSS, Co. Cork) and the Kilmaley Standard System (KSS,Co. Clare), classified as lower and high rainfall (1025 and 1614 mm yr) and free draining versus poor draining respectively.

Quantification Of Co2 Exchange In Grassland Ecosystems Of The World Using Tower Measurements, Modeling And Remote Sensing, Tagir Gilmanov, M. W. Demment, B. K. Wylie, K. Akshalov, D. D. Baldocchi, L. Belelli, J. A. Bradford, G. G. Burba, R. L. Coulter, W. A. Dugas, W. E. Emmerich, L. B. Flanagan, A. B. Frank, J. Fuher, M. R. Haferkamp, M. B. Jones, D. A. Johnson, T. Laurila, A. Lohila, T. P. Meyers, P. C. Mielnick, J. A. Morgan, M. Nasyrov, C. E. Owensby, M. S. Pekour, K. Pilegaard, A. Raschi, N. Z. Saliendra, M. J. Sanz, P. L. Sims, R. H. Skinner, J. F. Sousanna, A. E. Suyker, L. L. Tieszen, Z. Tuba, R. Valentini, S. B. Verma, E. A. Laca

IGC Proceedings (1977-2023)

Grasslands cover significant areas in nontropical regions, perform essential biogeochemical functions and represent important natural and agricultural resource. Nevertheless, in contrast to forests and agroecosystems, no flux measurement-based global summary of their CO₂ exchange, sequestration potential, and role in mitigation of the greenhouse effect were available.

The Influence Of Local Immigration And Extinction Of Species On Spatial Heterogeneity Of Vegetation In Semi-Natural Grasslands In Japan, Taisuke Yasuda, Masae Shiyomi, T. Egawa, K. Sei, R. Ishikawa, S. Takahashi

IGC Proceedings (1977-2023)

Spatiotemporal variation in the local immigration and extinction of species in a community may form and change the spatial heterogeneity (SH) of vegetation but few studies have evaluated the influences of these processes on SH. SH often occurs in grassland grazed by cattle and sheep. Understanding the formation and dynamics of SH is important because SH profoundly affects local and regional ecological processes. We propose a new way to quantify the effect of the local immigration and extinction of species on SH, and try to clarify the influence of the processes on SH

Cattle Slurry Amended With Nitrification Inhibitors: Effects On Nitrous Oxide, Dinitrogen And Methane Emissions, J. P. Carneiro, L. Cardenas, D. Hatch, H. Trindade, J. Hawkins, David Scholefield, D. Chadwick

IGC Proceedings (1977-2023)

In recent decades, a very intensive dairy farming system has been developed in northern Portugal. Considering the appreciable amounts of slurry generated and the small farm areas for spreading, this activity involves large annual inputs of N with the risk of undesirable consequences for the environment. Emission of greenhouse gases from agricultural sources, such as N₂O (originating from nitrification and denitrification) and CH₄, therefore need to be reduced. The aim of this laboratory experiment was to evaluate the effectiveness of two nitrification inhibitors (dicyandiamide (DCD) and 3,4-dimethylpyrazole phosphate (DMPP)) in reducing nitrification and subsequent denitrification after …

Methane Production By Cattle Grazed At Two Stocking Rates On A Semi-Natural Grassland, Cesar S. Pinares-Patiño, Y. Rochette, M. Fabre, J.-P. Jouany, C. Martin

IGC Proceedings (1977-2023)

Global warming induced by the human-enhanced concentrations of greenhouse gases (GHG) in the atmosphere is a major environmental concern of our day. Enteric methane (CH₄) is the most important GHG associated with grazing livestock. The emissions of methane may be influenced by environmental conditions and grazing management. Stocking rate (SR), the number of animals per unit of land area, remains the simplest management tool in pastoral farming. However, little is known about the influence of SR on CH₄ emission. The objective of this study was to compare the CH₄ emissions from cattle managed under low and …

Carbon Accumulation Under Brachiaria Pastures In The Brazilian Cerrado In Relation To Their Productivity, R. M. Boddey, S. P. Braz, R. S. M. Dos Santos, B. J. R. Alves, S. Urquiaga

IGC Proceedings (1977-2023)

Vast areas of land within Brazil has been converted from either the native vegetation of the Amazon and Atlantic forests or the native vegetation (NV) of the central savanna region (the Cerrado) to Brachiaria spp pastures. Productive pastures (PPs) in these regions eventually accumulate soil carbon (C) in excess of levels under native vegetation. However the effect of pasture degradation on soil C stocks has not been reported. We compared soil C stocks under both NV and Brachiaria pastures varying in productivity according to the indicators of Oliveira et al. (2004) over 5 sites in the Cerrado region.

Comparison Of Methodological Tools In Tropical Soil Carbon Sequestration Field Research, Bram Van Putten, M. C. Amézquita

IGC Proceedings (1977-2023)

Models play a crucial role in studying complex systems like soil Carbon sequestration processes (Hanson et al., 2001). A Carbon sequestration research project is currently under way in pasture and silvopastoral systems of four Tropical American ecosystems. A main research question is the identification of Land Management Systems (LMS) that exhibit optimal soil Carbon sequestration capacity (identification question). Another main issue is the extrapolation of data in space and time (extrapolation question).

Effects Of Tropical Legumes With Contrasting Tannin Contents And Mixtures Of Them On In Vitro Ruminal Fermentation And Methanogenesis, H. D. Hess, F. L. Valencia, P. Avila, C. E. Lascano, Michael Kreuzer

IGC Proceedings (1977-2023)

Previous in vitro experiments have showed that the supplementation of a low-quality grass diet with Arachis pintoi or Cratylia argentea (legumes low in tannins) enhanced ruminal fermentation and methane release, whereas the supplementation with Calliandra calothyrsus (rich in tannins) decreased methane release and suppressed organic matter (OM) degradation and N turnover (Hess et al., 2003). It was hypothesised that a mixture of tanniniferous legumes with legumes free of or low in tannins would result in a methane-suppressing effect but without impairing ruminal nutrient degradation.