Agronomy and Crop Sciences Commons^™

Genome-Wide Association Analysis For Emergence Of Deeply Sown Rice (Oryza Sativa) Reveals Novel Aus-Specific Phytohormone Candidate Genes For Adaptation To Dry-Direct Seeding In The Field, Sandeep A. Sakhale, Shailesh Yadav, Lindsay V. Clark, Alexander E. Lipka, Arvind Kumar, Erik J. Sacks

Department of Agronomy and Horticulture: Faculty Publications

Dry direct-seeded rice (dry-DSR) is typically sown deeply to circumvent the need for irrigation, and thus seedling emergence is a crucial trait affecting plant stand and yield. To breed elite cultivars that use less water and are climate-resilient, an understanding of the genomic regions and underlying genes that confer emergence in deeply sown dry-DSR would be highly advantageous. A combined diversity panel of 470 rice accessions (RDP1 plus aus subset of 3K RGP) was evaluated with 2.9 million single nucleotide polymorphisms (SNPs) to identify associations with dry-DSR traits in the field and component traits in a controlled-environment experiment. Using genome-wide …

Genomic Approaches To Enhance Adaptive Plasticity To Cope With Soil Constraints Amidst Climate Change In Wheat, Roopali Bhoite, Yong Han, Alamuru Krishna Chaitanya, Rajeev K. Varshney, Darshan L. Sharma

Grain and Other Field Crops Research Articles

Climate change is varying the availability of resources, soil physicochemical properties, and rainfall events, which collectively determines soil physical and chemical properties. Soil constraints—acidity (pH < 6), salinity (pH ≤ 8.5), sodicity, and dispersion (pH > 8.5)—are major causes of wheat yield loss in arid and semiarid cropping systems. To cope with changing environments, plants employ adaptive strategies such as phenotypic plasticity, a key multifaceted trait, to promote shifts in phenotypes. Adaptive strategies for constrained soils are complex, determined by key functional traits and genotype × environment × management interactions. The understanding of the molecular basis of stress tolerance is particularly challenging for plasticity traits. Advances in sequencing and high-throughput genomics …

International Rice Outlook: International Rice Baseline Projections 2022-2032, A. Durand-Morat, S. Bairagi, W. Mulimbi

AAES Research Reports and Research Bulletins

Rice prices in Asia increased since the Summer of 2022 mainly due to worries about a reduction in rice production in India caused by an abnormal monsoon season (Fig. 1). The upward trend in export prices solidified after India implemented a 20% export tariff on brown and milled long-grain rice, and a complete ban on exports of broken rice, in September 2022 to curve down exports and release the pressure on domestic rice prices. India’s rice export prices increased since then and proportionally to the value of the export tax. The latest estimates put rice production at 128 million metric …

Impact Of Nitrogen Availability On The Accumulation Of Vegetative Lipids In Sorghum, Leticia Felicio Pasqualino

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

Sorghum (Sorghum bicolor (L.) Moench) is a versatile and prosperous feedstock crop for renewable energy production. With the increase in bioenergy demand, the production of higher oil content per biomass in a feedstock crop is a highly desirable trait for the biofuel conversion process yield. Especially if this outcome can be achieved using fewer inputs in the field, such as nitrogen. In microalgae species, nitrogen limitation has been associated with changes in the carbon storage metabolic pathway favoring triacylglycerol (TAG) accumulation. In this context, this study aimed to assess whether nitrogen starvation would result in a similar outcome in …

Effect Of Rice Leaf Stage On Tolerance To Benzobicyclon In A Drill-Seeded Production System, Jake A. Patterson, Jason K. Norsworthy, Thomas R. Butts, Edward E. Gbur

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Benzobicyclon is a new postflood-applied herbicide that was registered for use in U.S. rice (Oryza sativa L.) in 2021 by Gowan Company. Therefore, research was conducted to evaluate tolerance of commonly grown rice cultivars to benzobicyclon. In 2018 and 2019, field experiments were conducted near Stuttgart, AR to evaluate the influence of growth stage on rice tolerance to benzobicyclon, and to evaluate pure line and hybrid rice tolerance to benzobicyclon following repeated use of acetolactate synthase-inhibiting herbicides. In one of two years, rice growth stage (leaf number) at application impacted tolerance to benzobicyclon. In 2018, the two-leaf application of …

Pestfacts Wa Issue 06 - June 2023, Benjamin S. Congdon, Rebecca Severtson

PestFacts WA

PestFacts WA Issue 6 - June 2023 contents:

• Green peach aphid alert
• 2023 winter spring insecticide guide is now available

Do Cover Crop Mixtures Improve Soil Physical Health More Than Monocultures?, Humberto Blanco-Canqui

Department of Agronomy and Horticulture: Faculty Publications

Rationale and Purpose — Adding multispecies cover crop (CC) mixtures could diversify the current simplified crop rotations and enhance soil health more than monoculture CCs. Further, CC mixtures with diverse plant species could adapt better to changing climatic and environmental conditions than monoculture CCs. However, our current understanding of the soil benefits of CC mixtures is still limited. This review discussed whether CC mixtures are better than monoculture CCs to improve soil physical health.

Methods — All studies published up to May 25, 2023, comparing soil physical properties between CC mixtures and their constituents grown as monocultures were searched in …

Arkansas Soybean Performance Tests 2022, J. F. Carlin, R. B. Mulloy, R. D. Bond

Arkansas Agricultural Experiment Station Research Series

Soybean variety and strain 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 varieties and/ or marketing seed within the state, and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for soybean producers.

Skim Resequencing Finely Maps The Downy Mildew Resistance Loci Rpf2 And Rpf3 In Spinach Cultivars Whale And Lazio, Gehendra Bhattarai, Ainong Shi, Beiquan Mou, James C. Correll

Horticulture Faculty Publications and Presentations

Commercial production of spinach (Spinacia oleracea L.) is centered in California and Arizona in the US, where downy mildew caused by Peronospora effusa is the most destructive disease. Nineteen typical races of P. effusa have been reported to infect spinach, with 16 identified after 1990. The regular appearance of new pathogen races breaks the resistance gene introgressed in spinach. We attempted to map and delineate the RPF2 locus at a finer resolution, identify linked single nucleotide polymorphism (SNP) markers, and report candidate downy mildew resistance (R) genes. Progeny populations segregating for RPF2 locus derived from resistant differential …

Herbicide Physiology And Environmental Fate, Luis Avila, Nilda Roma-Burgos

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Editorial

Herbicide Physiology and Environmental Fate

Effect Of Condensed Tannins In Sainfoin On In Vitro Protein Solubility Of Lucerne, J. Aufrère, M. Dudilieu, C. Poncet, R. Baumont

IGC Proceedings (1977-2023)

Proteins of fresh legume forages such as lucerne are highly degraded in the rumen, resulting in their inefficient use by the animal. The condensed tannins (CT) present in some forages can improve the nutritional value of these forages and of associated feeds in the diet. Previous in vitro work (Waghorn & Shelton, 1997) showed that CT from Lotus corniculatus are able to bind with and precipitate protein from a ryegrass/clover pasture, but when these forages were fed to sheep, the CT effects on digestion and animal performance were weak. This revealed a need for a better understanding of the mechanism …

Herbage Production, Nitrogen Fixation And Condensed Tannin Concentrations In Lotus Glaber Mill. Germplasm, H. Acuña, M. Figueroa, P. Hellman, A. Concha

IGC Proceedings (1977-2023)

Lotus glaber (Lg) grows on clay, sandy and medium textured soils in central Chile (32º to 38º S). The diversity of environments where the species grows naturally supports the hypothesis that genetic variability would be found. The objectives of the experiment were to characterise accessions of Lg collected in the region for dry matter (DM) production, comparative capacity to fix atmospheric N and condensed tannins (CT) in Lg grown on clay soils used for cropping rice.

Condensed Tannins In Different Varieties Of Lotus Corniculatus, Christina L. Marley, Rhun Fychan, R. Jones

IGC Proceedings (1977-2023)

Research has shown that Lotus corniculatus may provide benefits as a grazing forage for ruminants, because of improved efficiency of protein utilisation in part due to the presence of condensed tannins (CT) in the forage. Lotus species have been found to contain different CT (Aerts et al., 1999). The aim of this experiment was to determine if differences exist in CT concentration among L. corniculatus varieties.

Ariation In Tannin Content And Morphological Traits In Lotus Corniculatus L. (Bird’S-Foot Trefoil), A. H. Marshall, F. Ribaimont, R. P. Collins, D. Bryant, M. T. Abberton

IGC Proceedings (1977-2023)

Lotus corniculatus L. (bird's-foot trefoil) is a potentially valuable species for UK grassland agriculture. The herbage contains proanthocyanidins, or condensed tannins (CT's), which help to reduce bloat, have anthelmintic properties, can protect protein in the rumen, and thus potentially reduce N losses to the environment. It is currently a relatively minor species within UK grassland, as available varieties lack persistence in mixed swards (Hopkins et al., 1996). The seed used is of foreign bred varieties with no varieties bred specifically for the UK environment. To explore the feasibility of breeding L. corniculatus for the UK, variation in morphological traits, …

Light Intensity Is Positively Correlated With The Synthesis Of Condensed Tannins In Lotus Corniculatus, Sergio Arcioni, T. Bovone, F. Damiani, F. Paolocci

IGC Proceedings (1977-2023)

The importance of Condensed Tannins (CT) in forage legumes has been well documented in several studies. The role of plant genetics in this field is the acquisition of competences in order to be able to modulate CT synthesis in leaves of these species. The role of light has been investigated in this work on the increase of condensed tannin levels in leaves of two contrasting genotypes of birdsfoot trefoil (Lotus corniculatus).

Condensed Tannin Concentration And Herbage Accumulation Of A White Clover Bred For Increased Floral Condensed Tannin, V. T. Burggraaf, S. L. Woodward, D. R. Woodfield, E. R. Thom, G. C. Waghorn, P. D. Kemp

IGC Proceedings (1977-2023)

White clover is a high quality feed for ruminants, however, its high protein content results in excessive urea excretion in urine and can cause bloat, reducing its potential value for animal production. The condensed tannins (CT) in some forages can reduce these problems, but plants may have poor agronomic performance. White clover produces CT in its flower heads, but herbage CT concentrations are normally too low to benefit animals. This paper reports CT concentrations and herbage accumulation over 2 years of an experimental line of white clover (HT) selected for increased flowering and floral CT concentrations.

Effects Of Simulated High-Sugar Forages On Grazing Behaviour Of Sheep, Gerald P. Cosgrove, A. J. Parsons

IGC Proceedings (1977-2023)

Sustaining an optimum composition in mixed-species pasture and in the diet of grazing animals is constrained by many factors. Altering the concentration of water soluble carbohydrate (WSC) of one species to improve its nutritional value for animals may not deliver the benefits in the assumed manner if it also affects preference and the balance of species in the pasture. Furthermore, associated changes in other constituents (e.g. fibre, protein) make it difficult to attribute animal responses solely to the manipulated trait (e.g. Lee et al. 2000). The objective of this study was to simulate changes in the concentration of water soluble …

High Floral Tannin White Clover Reduces Rumen Ammonia Concentrations In Dairy Cows, V. T. Burggraaf, G. C. Waghorn, S. L. Woodward, D. R. Woodfield, E. R. Thom, P. D. Kemp

IGC Proceedings (1977-2023)

White clover produces high quality forage for ruminant production, but it results in high rumen ammonia concentrations, indicating extensive protein degradation. The excess ammonia is absorbed through the rumen and excreted as urea in urine, at a cost to the animal and the environment. Condensed tannins (CT) contained in some forages reduce proteolysis in the rumen, which can lead to increased amino acid absorption and therefore improved animal performance. White clover produces CT in its flower heads, but concentrations are normally too low to benefit animals. This paper reports on comparisons of rumen ammonia concentrations in dairy cows grazing HT …

Substrate-Dependent Activation Of Polyphenol Oxidase In Red Clover, Ana L. Winters, F. R. Minchin, P. Morris

IGC Proceedings (1977-2023)

Polyphenol oxidases (PPO) are copper metaloproteins that catalyse the oxidation of o-diphenols to quinones, highly reactive molecules which readily bind to nucleophilic sites on cellular components and proteins. Red clover protein, due to this enzyme is resistant to protease degradation during. Theses enzymes (circa. 60-65 kDa) are located in the thylakoid lumen and can be converted to a 40-45 kDa form by proteolysis both in vitro and in vivo (Gelder et al., 1997). Conversion to the smaller form has been demonstrated to confer activity at neutral pH. Other treatments, such as the presence of lipids or detergents …

Variation In Protein Quality Of Forage Legumes During Spring Growth, M. Gierus, J. Kleen, F. Taube

IGC Proceedings (1977-2023)

The utilisation of forage legumes in combination with reduced N inputs as fertilisers is an alternative for the production of high quality forage. Although white clover (WC) is widely used in grassland and has a high content of crude protein (CP), a combination of this high CP content with a high proportion of rapidly-available proteins and fast degradation rate in the rumen may reduce the efficiency of N use by ruminants in comparison with other forage legumes. The objective of the present study was to investigate the variation in content of CP fractions A, B and C in different forage …

Effects Of Particle Size In Forage Samples For Protein Breakdown Studies, G. Pichard, C. Tapia

IGC Proceedings (1977-2023)

Coupling ruminal processes of hydrolysis and synthesis continues to be a research issue where more progress is needed. This requires the development of good protein assessment methods, particularly when representing the breakdown processes that occur in fresh pastures eaten by herbivores. Laboratory analyses need to deal with small and homogeneous samples, but the mechanical reduction of particle size may not reflect the actual digestion kinetics occurring when the original fresh forage is consumed. Such physical traits may alter the release of non-structural compounds and the penetration of microbial enzymes (Boudon et al., 2002). The objective of this work was …

Ruminal Disappearance And Passage Rates In Fresh Nezasa Dwarf Bamboo Growing In Japanese Native Pasture, Masato Yayota, J. Karashima, T. Kokestu, M. Nakano, Shigeru Ohtani

IGC Proceedings (1977-2023)

Nezasa dwarf bamboo (Pleioblastus chino makino) is one of major native forages for grazing in Japan. However its nutritional utilisation in the rumen has been little studied. The object of this research was to measure ruminal disappearance and passage rates in fresh Nezasa dwarf bamboo compared with improved grass.

Ruminal Dry Matter, Neutral Detergent Fibre And Acid Detergent Fiber Degradation Kinetics Of Dominant Pasture Forages In Kurdestan Province Of Iran, A. A. Sadeghi, P. Shawrang, A. Nikkhah

IGC Proceedings (1977-2023)

Neutral detergent fiber (NDF) is a major chemical component of forages and its degradability (dNDF) is an essential parameter in predicting their energetic value. Moreover, dNDF has been used in models to estimate the physical fill of fibrous feeds in the rumen and, therefore, the intake capacity of animals. As the available information on the nutritive value of pastoral forages is limited a study was undertaken to measure chemical composition and cell wall degradation kinetics of eight pasture forages in the rumen.

The Effects Of Urease Source And Moisture Content On The Nutritive Value Of Brachiaria BrizantHa Hay Treated With Urea, Ricardo A. Reis, L. M. A. Bertipaglia, G. M. P. Melo, A. P. Oliveira, S. Luca

IGC Proceedings (1977-2023)

Ammoniation has a high potential to increase the nutritive value (NV) of mature tropical grasses hays. Urea utilisation, like ammonia, seems to be a promising alternative for on-farm treatment of low quality forage in Brazil. Urea has the advantages over anhydrous ammonia of being widely available, easier to handle and, in some countries, less expensive. The aim of this work was to study the effects on the efficiency of urea treatment of palisade grass (Brachiaria brizantha cv. Marandu) hay of the moisture level, and the urease source.

Herbage Mass And In Situ Dry Matter Ruminal Degradation Kinetics Of Brachiaria Spp, E. Valencia-Chin, A. A. Rodríguez-Carías, R. Ramos-Santana, S. Pagán-Riestra

IGC Proceedings (1977-2023)

In Puerto Rico, Brachiaria decumbens cv. Basilisk has been promoted as a potential forage for acid soils and humid areas, but with limited success. Recently, B. brizantha cv. Marandú and a hybrid (B. brizantha x B. Ruziziensis) cv. Mulato were introduced for evaluation on acid soils and as a potential replacement for cv. Basilisk, but little information is available on yield performance under grazing or nutritive value. The objective of this study was to assess herbage mass and nutritive value of grazed pastures consisting of Basilisk, Marandú, and Mulato and determine the rate of in situ dry matter …

Physical Impediment Towards Digestive Breakdown In Leaf Blades Of Brachiaria Brizantha, B. Lempp, Cacilda B. Do Valle, M. Das G. Morais, R. A. Borges, E. Detmann

IGC Proceedings (1977-2023)

Consumption of grasses is influenced by the physical properties of forages which confer resistance to digestive breakdown. Such barriers may be the proportion of indigestible tissues, girder structure and epidermal cell arrangements. Anatomical factors, if identified early are invaluable tools in breeding and selection programmes for forages of high quality. The objective of this study was to verify which anatomical attributes might be interfering in the physical resistance to rumen breakdown in Brachiaria brizantha ecotypes.

Effects Of Forage Species And Stage Of Maturity On In Situ Disappearance Of Organic Matter And Fibre Fractions, H. S. Hussein

IGC Proceedings (1977-2023)

Nutrient utilisation by ruminants is altered by the forage species and its maturity. Maturity is the major factor affecting forage morphology and quality. Forage quality is reduced with maturity due to a decrease in the leaf:stem ratio and an increase in fibre components (Ugherughe, 1986). Improving forage utilisation by ruminants depends on accurate measurements of their nutritive value by using in vitro and in situ methods. The objective of this study was to assess the nutritive value (i.e., extent of in situ disappearance of organic matter [OM], neutral detergent fibre [NDF], and acid detergent fibre [ADF]) of four grass species …

The Effect Of Nitrogen Fertiliser And Season On The In Situ Degradability Of Irish Perennial Ryegrass In Cattle, V. Olsson, J. J. Murphy, F. P. O'Mara, K. O'Connell, J. Humphreys, F. J. Mulligan

IGC Proceedings (1977-2023)

In light of increasing environmental and economic pressure on agriculture to utilise resources more efficiently, protein feeding and its effects are fundamentally important. As grazed grass is the predominant feed in Irish dairy and beef cattle production systems, it is necessary to establish protein values for different grass varieties and cultivars fed. It is also important to investigate the extent of ruminal nitrogen (N) degradability for these grasses since this characteristic greatly influences environmentally damaging urinary N excretion.

The Effect Of Cow-Diet On The Fermentation Of Forages, J. L. Burke, G. C. Waghorn, S. L. Woodward, I. M. Brookes

IGC Proceedings (1977-2023)

In vitro fermentation of fresh forages minced to resemble chewed material have enabled net proteolysis and volatile fatty acid (VFA) production to be measured using rumen inocula from a cow fed lucerne hay (Burke et al., 2000). However both cow and diet affect the rumen cellulolytic bacterial populations (Weimer et al., 1999) and are able to influence in vitro digestion kinetics (Mertens et al., 1998). The objective of this study was to measure cow-diet effects on in vitro digestion and fermentation of perennial ryegrass (P; Lolium perenne), sulla (S; Hedysarum coronarium), maize (M; Zea maize …

Fibre Degradation Rate Of Perennial Ryegrass Varieties Measured Using Three Techniques: In Situ Nylon Bag, In Vivo Rumen Evacuation And In Vitro Gas Production, H. Z. Taweel, B. M. Tas, B. A. Williams, A. Elgersma, J. Dijkstra, S. Tamminga

IGC Proceedings (1977-2023)

In Western Europe, perennial ryegrass is the most widely used grass species for grazing cattle, because of its high productivity, palatability and nutritive value. However, the low dry matter intake (DMI) of perennial ryegrass pasture has been identified as a major factor limiting milk production of high producing dairy cows. Altering the chemical, physical and mechanical characteristics that contribute to its low DMI through grass breeding and the choice of variety may be a way forward in trying to maximise its DMI. This study aimed to examine whether perennial ryegrass varieties differ in their NDF degradation rates (kd_NDF).