Plant Biology Commons^™

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard A. Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

Likelihood-Based Tests Of Species Tree Hypotheses, Richard Adams, Michael Degiorgio

Entomology and Plant Pathology Faculty Publications and Presentations

Likelihood-based tests of phylogenetic trees are a foundation of modern systematics. Over the past decade, an enormous wealth and diversity of model-based approaches have been developed for phylogenetic inference of both gene trees and species trees. However, while many techniques exist for conducting formal likelihood-based tests of gene trees, such frameworks are comparatively underdeveloped and underutilized for testing species tree hypotheses. To date, widely used tests of tree topology are designed to assess the fit of classical models of molecular sequence data and individual gene trees and thus are not readily applicable to the problem of species tree inference. To …

Do Species Matter? Examining The Niche Of White Ash (Fraxinus Americana L.) And Estimating Potential Subcanopy Effects Of Its Loss In North-Temperate Forests, Elizabeth Anne Studer

Dartmouth College Ph.D Dissertations

To understand the downstream consequences of the extinction of a species, we must understand its role in an ecosystem. With the impending extirpation of ash (Fraxinus spp.) due to the invasive emerald ash borer (Agrilus planipennis), understanding the role of ash trees is critical to predicting whether its loss will precipitate further species declines and/or ecosystem functions. We evaluated whether subcanopy microbial, invertebrate, and floral communities under four tree species (white ash, American beech, yellow birch, sugar maple) and on two soil hydropedological types (Bh podzol and Typical podzol) varied in species richness, composition, and functional traits in a factorial …

Arkansas Corn And Grain Sorghum Research Studies 2022, Victor Ford, Jason Kelley, Nathan Mckinney Ii

Arkansas Agricultural Experiment Station Research Series

The 2022 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, and insect management; economics; sustainability; irrigation; post-harvest drying; soil fertility; mycotoxins; cover crop management; and research verification program results. 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.

Reports in this publication are 2–3 year summaries. …

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 …

Efficacy Of The Botanical Extracts, Azadirachta Indica (Sapindales: Meliaceae) And Tagetes Minuta (Asterales: Asteraceae) In The Control Of Cabbage Insect Pests In Iringa District, Tanzania, Levocatus M. Rwegoshora, Vendeline E. Tairo, Moses I. Olotu

Tanzania Journal of Science

Although botanical extracts have been widely studied globally, the efficacy of neem and Mexican marigold against cabbage insect pests is scanty. Field experiments were conducted at Kalenga and Mgera in 2022 using a randomized complete block design. Four treatments (neem, Mexican marigold, a mixture of the two extracts and untreated) were replicated three times. In Kalenga, damage levels for treated plots varied significantly from 3.33 to 9.20% and 5.0 to 18.33%, while for untreated plots varied from 37.70 to 45.85% during the rainy and dry seasons, respectively (F(3, 499) = 111.71, p < 0.05). A similar trend was recorded in Mgera, the damage levels varied significantly between treated (4.44–15.83%) and untreated plots (34.40–46.60%) (F(3, 449) = 94.23, p < 0.05). Treated plots had higher marketable cabbage yields (30.6–43.10 t/ha) than untreated plots (4.78–11.20 t/ha), which differed significantly in Kalenga (F (3, 67) = 141.79, p < 0.05) and Mgera (F (3, 67) = 53.36, p < 0.05). These extracts have shown insecticidal properties, can serve as promising candidates for further studies aimed at isolating active compounds for scaling up ecologically friendly strategies of controlling pests and improve the quality of cabbage products.

Plant-Based Ice Cream: Processing, Composition And Meltdown Properties Analysis, Victor Vicent Matabura

Tanzania Journal of Science

Abstract Plant-based foods have become a popular option for consumers due to their positive impacts on health and resulting changes in lifestyle. To preserve the quality of non-dairy ice cream during distribution and consumption, it is essential to understand its proximate composition and meltdown properties. In this study, cashews, coconut, and bananas were used as raw materials. Cashew milk and coconut cream were prepared separately and mixed at different ratios to make non-dairy ice cream. The proximate composition of the formulated ice cream was measured using the official standard methods. The meltdown properties, including drip-through (%), height (mm), and temperature …

Effects Of Roasting Conditions On The Proximate Composition And Functional Properties Of Common Bean (Phaseolus Vulgaris) Flours, Rachel Byarugaba, Agnes Nabubuya, John Muyonga, Ali Mwakha

Tanzania Journal of Science

Roasting of dry beans presents the possibility of a value-added product with improved nutritional quality and potential use in different food systems. The effect of roasting on the proximate composition and functional properties of dry beans (Phaseolus vulgaris L.) was determined. Beans were roasted at 140, 170, and 200 °C for 5, 10, and 15 minutes. The moisture, carbohydrate, protein, dietary fibre, total ash and fat contents of the flours ranged from 4.58 to 6.72%, 56.21 to 60.51%, 23.09 to 26.74%, 4.12 to 7.01%, 3.94 to 4.58% and 1.28 to 2.10%, respectively. An increase in roasting temperature and time significantly …

In-Vitro Antisickling Activity Of Pergularia Daemia, Canna Indica And Petiveria Alliacea Plants Used In The Treatment Of Sickle Cell Anaemia In Edo State, Nigeria, Osaro Iyekowa, Felix E Okieimen, Clifford O Ehisuoria

Tanzania Journal of Science

Sickle cell disease is a genetic blood disorder that affects the shape and transportation of the red blood cells (RBCs) in blood vessels, leading to various clinical complications. Available medicines for treating the disease are insufficiently effective, toxic or expensive. Therefore, there has been a pressing need for effective and inexpensive therapeutic agents from indigenous medicinal plants. Petiveria alliacea, Canna indica and Pergularia daemia, respectively were evaluated for their cationic constituents as a measure for their antisickling activity in sickle cell anaemia disorder. The three medicinal plants were extracted separately with methanol solvent using maceration method for 72 hours. The …

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, …

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) …

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 …