Plant Pathology Commons^™

Plant Diversity Patterns Along Altitudinal Gradient In Understory Communities Of Darkesh Region, Bojnord, Iran, A. Arjmandi, H. Ejtehadi, F. Memariani, Mansour Mesdaghi

IGC Proceedings (1977-2023)

The ecotone region of Darkesh with an area of 22,500 hectares is located in the Irano-Turanian xeric-continental bioclimatic zone of Khorassan-Kopet Dagh. To investigate the plant diversity patterns of understory communities along three elevation classes of 1100-1600, 1600-2100, and 2100-2600 m, 187 plots were sampled randomly and abundance and cover of species were recorded using 4-m² plots. Beta diversity and Hill indices were calculated by using R and PAST software. A total of 252 species were recorded including 31 perennial grasses. The most abundant grasses were Poa nemoralis, Poa bulbosa, Bromus sterilis, Brachypodium sylvaticum, and Dactylis glomerata subsp. glomerata …

Using Genetic Diversity In Deep Root Systems Of Perennial Forage Grasses And Rice To Capture Carbon In Tropical Soils, J. Arango, Daniel M. Villegas, R. N. Jauregui, J. A. Cardoso, C. Costa Jr., C. Rebolledo, M. F. Alvarez, M. Selvaraj, L. Rodriguez, M. Mayorga, P. Chavarriaga, A. Notenbaert, M. Quintero, M. Da Silva, Manabu Ishitani, M. Peters, I. Rao, Joe Tohme

IGC Proceedings (1977-2023)

Agricultural soils have the potential not only to be sinks of carbon dioxide (CO₂) but also to mitigate the emissions of this gas to the atmosphere, thus, alleviating global warming. Perennial tropical grasses and rice upland and lowland varieties exhibit a large untapped genetic diversity in their root systems (e.g., deep rooting ability, exudation rates and chemical composition) that, if unlocked, could contribute to increased food production in crop-livestock systems while enhancing soil organic carbon (SOC) in tropical regions. Naturebased solutions that improve crop adaptation and SOC storage in tropical soils could help to remove CO₂ from …

Salt Tolerance Mechanisms In Perennial Fodder Grasses, Edna Antony, B. Aravind, A. Amulya, T. Anushree, P. V. Rakshata, F. H. Savitha, M. B. Doddamani, P. V. Kuligod, Akbar, Vinod Kumar, K. Sridhar, Vijay Kumar Yadav

IGC Proceedings (1977-2023)

Salinity stress is one of the most damaging stresses in crop plants. It reduces the productivity of the soil and makes it unsuitable for crop cultivation. Fodder crops are considered the best alternative in such uncultivable land. Using salinity-affected land for pasture development is the best alternative to utilize such lands. However, the extent of salinity tolerance varies among different grass species. In this study, Pearl millet Napier hybrids (PMN hybrid) and guinea grass varieties were studied for salinity tolerance in artificially created saline soils in the ratio of 13:7:1:2 (NaCl: Na₂SO₄: MgCl: CaSO₄, …

Effect Of Soil Nitrogen And Water Content On The Establishment Of A Lolium Perenne L. And Trifolium Repens L. Pasture, M. F. Alonso, Oscar A. Balocchi, I. Calvache, O. Martínez

IGC Proceedings (1977-2023)

Climate change has decreased rainfall in Southern Chile affecting the productivity of the grasslands that sustain the dairy and beef cattle industries. These grasslands are mainly mixtures of Lolium perenne L. and Trifolium repens L. Thus, we study the response on the establishment of a mixture of these two species to three levels of soil water content and two levels of nitrogen (N) fertilization. The trial was carried out in containers sowed in a complete randomized block´s design. Soil moisture measurements were taken daily. N fertilizations was applied at the establishment and every 60 days. Leaf appearance rate was measured …

Impact Of Level Of Use On Plant Vigor And Weight Of Festuca Humilior And Calamagrostis Vicunarum, T. Edson, L. Aguirre, E. R. Flores

IGC Proceedings (1977-2023)

Tussock grasslands of Festuca humilior and Calamagrostis vicunarum cover a significant extension of the central Andes of Peru, constituting a plant association highly appreciated by cattle ranchers. The objective of this research was to estimate the cumulative impact of the level of use of the key grasses Festuca humilior and Calamagrostis vicunarum on plant height, vigor, and weight. This study was conducted in a humid grassland of regular condition located at 4186 masl in the Puna ecoregion. The variables evaluated were: plant height, basal and canopy diameter and plant weight. The experiment lasted two years in which individual plants from …

Janus , A Spliceosome-Associated Protein, Promotes Mirna Biogenesis In Arabidopsis, Mu Li, Huihui Yu, Bangjun Zhou, Lu Gan, Shengjun Li, Chi Zhang, Bin Yu

Center for Plant Science Innovation: Faculty Publications

MicroRNAs ( miRNAs ) are important regulators of genes expression. Their levels are precisely controlled through modulating the activity of the microprocesser complex ( MC ) . Here, we report that JANUS, a homology of the conserved U2 snRNP assembly factor in yeast and human, is required for miRNA accumulation. JANUS associates with MC components Dicer-like 1 ( DCL1 ) and SERRATE ( SE ) and directly binds the stem- loop of pri-miRNAs. In a hypomorphic janus mutant, the activity of DCL1, the numbers of MC, and the interaction of primary miRNA transcript ( pri-miRNAs ) with MC are reduced. …

The Pseudomonas Syringae Pv. Tomato Dc3000 Effector Hopd1 Interferes With Cellular Dynamics Associated With The Function Of The Plant Immune Protein Atnhr2b, Luis Francisco Marin-Ponce, Catalina Rodriguez-Puerto, Perla Rocha-Loyola, Clemencia M. Rojas

Entomology and Plant Pathology Faculty Publications and Presentations

The plant pathogenic bacterium Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) causes disease in tomato, in the model plant Arabidopsis thaliana, and conditionally in Nicotiana benthamiana. The pathogenicity of Pst DC3000 is mostly due to bacterial virulence proteins, known as effectors, that are translocated into the plant cytoplasm through the type III secretion system (T3SS). Bacterial type III secreted effectors (T3SEs) target plants physiological processes and suppress defense responses to enable and support bacterial proliferation. The Pst DC3000 T3SE HopD1 interferes with plant defense responses by targeting the transcription factor NTL9. This work shows that HopD1 also targets the …

Arkansas Wheat Performance Tests 2022-2023, J. F. Carlin, R. B. Mulloy, R. D. Bond

Arkansas Agricultural Experiment Station Research Series

Wheat variety performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture’s Arkansas Crop Variety Improvement Program.

The tests provide information to companies developing cultivars and marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for small-grain producers. The tests were conducted at the Northeast Research and Extension Center at Keiser, the Vegetable Substation near Kibler, the Lon Mann Cotton Research Station near Marianna, the Pine Tree Research Station near Colt, and the Rohwer Research Station near Rohwer. Specific location and cultural practice information accompany each …

Dynamic Reconfiguration Of Switchgrass Proteomes In Response To Rust (Puccinia Novopanici) Infection, Nathan A. Palmer, Sophie Alvarez, Michael J. Naldrett, Anthony Muhle, Gautam Sarath, Serge J. Edmé, Satyanarayana Tatineni, Robert B. Mitchell, Gary Yuen

Department of Plant Pathology: Faculty Publications

Switchgrass (Panicum virgatum L.) can be infected by the rust pathogen (Puccinia novopanici) and results in lowering biomass yields and quality. Label-free quantitative proteomics was conducted on leaf extracts harvested from non-infected and infected plants from a susceptible cultivar (Summer) at 7, 11, and 18 days after inoculation (DAI) to follow the progression of disease and evaluate any plant compensatory mechanisms to infection. Some pustules were evident at 7 DAI, and their numbers increased with time. However, fungal DNA loads did not appreciably change over the course of this experiment in the infected plants. In total, 3830 …

Overcoming Genetic Paucity Of Camelina Sativa: Possibilities For Interspecific Hybridization Conditioned By The Genus Evolution Pathway, Rostyslav Y. Blume, Ruslan Kalendar, Liang Guo, Edgar B. Cahoon, Yaroslav B. Blume

Center for Plant Science Innovation: Faculty Publications

Camelina or false flax (Camelina sativa) is an emerging oilseed crop and a feedstock for biofuel production. This species is believed to originate from Western Asian and Eastern European regions, where the center of diversity of the Camelina genus is located. Cultivated Camelina species arose via a series of polyploidization events, serving as bottlenecks narrowing genetic diversity of the species. The genetic paucity of C. sativa is foreseen as the most crucial limitation for successful breeding and improvement of this crop. A potential solution to this challenge could be gene introgression from Camelina wild species or from …

A Facile Agrobacterium‑Mediated Transformation Method For The Model Unicellular Green Algae Chlamydomonas Reinhardtii, Truyen N. Quach, Shirley J. Sato, Mark R. Behrens, Paul N. Black, Concetta C. Dirusso, Heriberto D. Cerutti, Tom Elmo Clemente

Center for Plant Science Innovation: Faculty Publications

A reliable and simple Agrobacterium-mediated transformation system for the unicellular green algae model organism Chlamydomonas reinhardtii has been developed. The protocol has been successfully employed with both neomycin phosphotransferase II (nptII) and the phleomycin resistance (bleI) genes coupled with the selective agents paromomycin and zeocin, respectively. A set of binary vectors were assembled that carry the selectable marker cassettes under control either of the Rbcs2 alone or fused to the HSP270A leader sequence, PsaD, or ß-tubulin2 promoters. The corresponding T-DNA elements also harbored a cassette with a codon-optimized version of yellow fluorescence protein (YFP) under …

Methionine Biosynthesis Enzyme Momet2 Is Required For Rice Blast Fungus Pathogenicity By Promoting Virulence Gene Expression Via Reducing 5mc Modification, Huimin Li, Pengcheng Mo, Jun Zhang, Zhuoer Xie, Xinyu Liu, Han Chen, Leiyun Yang, Muxing Liu, Haifeng Zhang, Ping Wang, Zhengguang Zhang

School of Medicine Faculty Publications

The emergence of fungicide resistance severely threatens crop production by limiting the availability and application of established fungicides. Therefore, it is urgent to identify new fungicidal targets for controlling plant diseases. Here, we characterized the function of a conserved homoserine O-acetyltransferase (HOA) from the rice blast fungus Magnaporthe oryzae that could serve as the candidate antifungal target. Deletion of the MoMET2 and MoCYS2 genes encoding HOAs perturbed the biosynthesis of methionine and S-adenyl methionine, a methyl group donor for epigenetic modifications, and severely attenuated the development and virulence of M. oryzae. The ΔMomet2 mutant is significantly increased in 5-methylcytosine (5mC) …

Genetic Improvement Of Tocotrienol Content Enhances The Oxidative Stability Of Canola Oil, Min Deng, Hao Chen, Wei Zhang, Edgar B. Cahoon, Yongming Zhou, Chunyu Zhang

Center for Plant Science Innovation: Faculty Publications

Background: Tocotrienols and tocopherols, which are synthesized in plastids of plant cells with similar functionalities, comprise vitamin E to serve as a potent lipid-soluble antioxidant in plants. The synthesis of tocopherols involves the condensation of homogentisic acid (HGA) and phytyl diphosphate (PDP) under the catalysis of homogentisate phytyltransferase (HPT). Tocotrienol synthesis is initiated by the condensation of HGA and geranylgeranyl diphosphate (GGDP) mediated by homogentisate geranylgeranyl transferase (HGGT). As one of the most important oil crops, canola seed is regarded as an ideal plant to efficiently improve the production of vitamin E tocochromanols through genetic engineering approaches. However, only …

Disease-Reducing Effect Of Calcium Salts Against Postharvest Diseases Of Mango (Mangifera Indica L. Cv. Carabao) Fruits, Melissa P. Montecalvo, Mary Joy C. Mendoza, Teresita U. Dalisay

The Philippine Agricultural Scientist

Mango fruits (Mangifera indica L. cv. Carabao) are susceptible to fungal infection, resulting in postharvest diseases. Chemical pesticides are used for disease management but may have a health impact and are costly. Therefore, alternatives to chemical control are necessary to minimize health risks and losses due to postharvest diseases. This research presented the disease-reducing effect of calcium salts, calcium chloride (CaCl₂) and calcium carbonate (CaCO₃), against mango stem end rot (SER) (sometimes caused by Lasiodiplodia theobromae) and anthracnose (caused by Colletotrichum gloeosporioides sensu lato). In in vitro assays, mycelial growth of both pathogens …

Effectiveness Of Arbuscular Mycorrhizal Fungi In Increasing Growth And Yield Of Maize Overlaid On Oil Palm Aged 4 Years, Cucu Suherman, Sri Desi Nurliawati, Mira Ariyanti, Intan Ratna Dewi, Mochamad Arief Soleh

Jurnal Kultivasi

The intercropping system in oil palm plantations is an effort to optimize land, especially at the immature stages (IS), which have a large open space between the trees, so it can be used for cultivating annual crops such as maize. Oil palm trees are generally planted on marginal lands, such as Inceptisol, which generally lacks in phosphor (P). These problems can be reduced by applying arbuscular mycorrhizal fungi (AMF) to elevate P. This experiment was to determine the dosage and effectiveness of AMF that can improve the growth and yield of maize intercropped with a 4-year-old oil palm. The experiment …

Scaling Up Of Site Carbon Dynamics To Predict The Carbon Dynamics In Kazakhstan, Central Asia, B. K. Wylie, Tagir Gilmanov, S. L. Stensaas, N. Z. Saliendra, D. A. Johnson, K. Akshalov, S. B. Frank, L. Zhang, R. F. Doyle, E. A. Laca, Montague W. Demment

IGC Proceedings (1977-2023)

Climate and management determine whether rangelands are net carbon sources or carbon sinks. Regional carbon dynamics of the Kazakh Steppe has not previously been documented. The objective of this study is to quantify the regional carbon flux dynamics of these extensive steppes.

A New System For Plant Experiments On Biodiversity Or Multi-Species Competition, John Connolly, L. Kirwan

IGC Proceedings (1977-2023)

Considerable discussion in recent years has focused on the design of competition and biodiversity experiments (Connolly et al., 2001a; Allison, 1999). Few agronomic experiments with >2 plant species have been conducted in greenhouse conditions (Gibson et al, 1999) or in the field (Connolly et al., 2001b). In many experiments the effects of density and initial species size have been confounded. The effects of species richness and evenness also are confounded frequently. The proposed system provides a framework of design and analysis, in which to address questions of function at community level and of structure and competition at …

Native Grasses Seeded Into A Cool-Season Pasture Encouraged By Low Resource Availability, J. E. Doll, R. L. Cates, R. D. Jackson

IGC Proceedings (1977-2023)

Native prairie of the Upper Midwest, which was dominated by warm-season (C₄) grasses, now exists as relatively small relict and restored patches (Curtis 1959). Re-introduction of natives into grazed agroecosystems would promote genetic, species, and landscape diversity. Extensive re-introduction of C₄ grasses will require a shift away from the paradigm of maximizing production because C₄ grasses have higher C:N ratios than C₃ grasses rendering them inferior forage species. Nonetheless, there is great interest amongst the grazing community of the Upper Midwest in establishing native grasses as a means of improving wildlife habitat and increasing belowground …

The Ag-Biota Project: A Preliminary Assessment Of Potential Indicators Of Biodiversity In Agricultural Grasslands, Gordon Purvis, A. Anderson, A. J. Helden, L. Kirwan

IGC Proceedings (1977-2023)

In compliance with European commitments to the Convention on Biological Diversity, the conservation and enhancement of biodiversity within agricultural land is a primary objective of current agri-environmental measures. However, there is a widespread lack of information concerning the effectiveness of agri-environmental schemes in Europe, (Kleijn & Sutherland, 2003). In large part, this is due to uncertainties about selection of appropriate biological indicators of biodiversity (Buchs, 2003; Duelli & Obrist, 2003).

Effects Of Plant Species Diversity In Multifunctional Grasslands On Avian Communities, K. K. Bakker, K. F. Higgins

IGC Proceedings (1977-2023)

Grasslands, planted or native sod, can provide multiple simultaneous functions (e.g., hay-forage production, biomass fuel products, bird nesting cover, soil and water conservation). Bird use of and abundance in grasslands is dependent on vegetation structure, size, and surrounding landscape (Bakker et al., 2002) but little is known about avian relationships to plant species diversity. We evaluated the relationship between plant species diversity and avian community structure in 5 grassland types. The results have application to grazing, haying, burning, and conservation practices applied to native and sown grassland stands and to conservation strategies for declining grassland bird populations.