Agronomy and Crop Sciences Commons^™

Physical Constraints In Grassland Ecosystems, I. M. Young, K. Ritz, C. S. Sturrock, R. Heck

IGC Proceedings (1977-2023)

Key points

1. Grassland system management must account adequately for biophysical and biochemical processes.

2. Amenity turf, especially sports turf, provides an excellent case study on how biology and physics interact to impact on the functioning of a grass ecosystem.

3. Microorganisms produce hydrophobic compounds that act to decrease water ingress and alter the function of the soil-grass ecosystem.

Adoption Of Brachiaria Grasses In Mexico And Central America: A Successful Story, F. Holmann, Pedro Argel, C. E. Lascano

IGC Proceedings (1977-2023)

In Latin America and the Caribbean (LAC) there has been a major effort to develop new pastures technologies, to increase livestock productivity for the extensive systems prevailing in the tropical lowlands. This multi-national and inter-institutional effort was initiated through the International Network for the Evaluation of Tropical Pastures (RIEPT, by its name in Spanish), which operated from 1976 to 1996 under CIAT leadership. This network became a platform for institutions to train technicians, share forage material from existing gene banks, study the behaviour of new germplasm under different environments, and established the exchange of scientific information to extrapolate research results …

Improved Livelihoods From Grasslands; The Case Of Napier Grass In Smallholder Dairy Farms In Kenya, David Miano Mwangi, D. Romney, S. Staal, I. Baltenweck, S. Mwendia

IGC Proceedings (1977-2023)

In Kenya, smallholder farmers produce about 80% of the marketed milk. The farming systems vary from mixed farms with up to 10 ha of land and < 10 dairy cows (Gitau et al., 1994; Anon., 1985), to intensive smallholder dairy producers in the high human population central Kenya region with 0.9 to 2 ha of land and 3-4 dairy cows (Staal et al., 2001a). Milk production depends heavily on the cultivation of forages, with Pennisetum purpureum (Napier grass) by far the most important. An estimated 350,000 of the 600,000 smallholder farms in Kenya grow and utilize P. purpureum on their farms.

There are …

Role Of Information And Information Providers In Technology Transfer, D. Undersander

IGC Proceedings (1977-2023)

Technology transfer is an essential component of economic change in society. Developers of new technology often fail to realize that there is a science to technology transfer. This lack of appreciation for the skills involved in information dissemination and in activities necessary to affect a change of action in an audience often severely limits the rate and amount of technology transfer that occurs. Significant differences exist between doing a news release or writing a publication and causing audience acceptance of a new technology. The old standards of expecting adoption of a new technology simply because it “will profit farmers” or …

The Contribution Of Participatory Research: On-Farm Research, P. F. Fennessy, N. J. Daniels, S. A. Chadwick, P. A. Speck

IGC Proceedings (1977-2023)

Participatory research in agriculture may range from research and technology development (R&D), carried out on a research station with some involvement of farmers, through to genuine participatory research involving researchers and farmers working together. The latter involves the end-user in actually carrying out aspects of the research and/or in the development and evaluation of technology that is appropriate to commercial enterprises. Researchers often question the validity of the ‘findings of on-farm participatory research’ as they are more comfortable with the ‘controlled’ environment of the research station. However if research is to be applied appropriately on farms, it must go through …

Participatory Research For Smallholder Livestock Systems: Applying Common Sense To Complex Problems, P. M. Horne, Werner Stür

IGC Proceedings (1977-2023)

Key Points:

1. Participatory approaches to research (PAR) bring researchers closer to farmers, the intended users of research outputs.

2. Active, functional participation of farmers in the evaluation and development of new technologies requires researchers to make an important commitment: respecting the knowledge, skills and opinions of farmers while maintaining confidence in their own scientific knowledge.

3. Farmer experimentation is not usually suitable to provide quantitative biophysical data (this can be achieved more effectively in researcher controlled experiments), but to provide qualitative information and improve understanding. This type of information can be collected systematically to enable rigorous analysis.

4. While …

Soil Biology And The Emergence Of Adventive Grassland Ecosystems, T. R. Seastedt

IGC Proceedings (1977-2023)

The last few years have seen an explosion of information on the responses and feedbacks of soil biota to species and environmental changes. Soil biologists, plant ecologists, and biogeochemists have been searching for patterns, generality and predictability in these relationships. A few brave souls have had the courage to assemble comprehensive assessments of soil biology in our rapidly changing world. Several years ago, I reviewed Wardle’s (2002) book emphasising the links between above- and belowground components of ecosystems. That activity – as well as the present one – provided me with the opportunity to survey recent findings in soil biology. …

Computer-Based Forage Management Tools: Historical, Current, And Future Applications, David B. Hannaway, C. Daly, D. F. Chapman, B. B. Baker, A. S. Cooper

IGC Proceedings (1977-2023)

Forage management has been an important human activity since the beginning of civilization. By comparison, the personal computer has been available only in the immediate past. The software developed to deal with the complexity of climate, soil, plant, animal, and socioeconomic factors has seen huge changes in a few decades. Mainframe computers facilitated numerical calculations for exploring relationships among dozens of variables. Personal computers opened the door for more individual scientist creativity and routine communication. Web-based communication globalised the option for multidisciplinary teams to tackle problems. Forage-related computer applications abound, allowing farmers, ranchers, and others to more effectively manage the …

Paying For Our Keep: Grasslands Decision Support In More-Developed Countries, Andrew D. Moore

IGC Proceedings (1977-2023)

“Models in grassland science have come to stay, and so they must be made to pay for their keep. To do that, it will be necessary to improve their scientific sophistication and their management relevance...” (Seligman, 1993).

Decision support (DS) tools in grassland agriculture have also come to stay. This review will examine the ways and means by which DS tools are being made to pay for their keep, with a focus upon DS efforts from the last decade and on the lessons that arise for those who develop DS tools for grasslands. A survey of the present state of …

Decision Support For Grassland Systems In Developing Countries, P. K. Thornton

IGC Proceedings (1977-2023)

Key points

1. Information flows in complex systems are often themselves highly complex, and decision support approaches based on linear input-output processes may have only limited impact.

2. How decisions are made, and how they can be appropriately supported, is often incompletely understood, in part because of inadequate understanding of the objectives and attitudes of all the decision makers involved.

3. Much of the developing world faces daunting problems in the coming 30 years, and appropriate information could play a critical role in dealing with these.

4. System complexity, household variability, and institutional intricacies have to be embraced rather than …

Identification Of Quantitative Trait Loci (Qtls) For Resistance To Bacterial Leaf Streak: Xanthomonas Translucens Using Qtl And Association Mapping In Three Populations Of Soft Red Winter Wheat, Benjamin Tyler Meritt

LSU Doctoral Dissertations

Bacterial leaf streak (BLS) and black chaff, caused by Xanthomonas translucens pv. undulosa (Xtu), can be a very destructive disease of wheat, especially in the warmer, wetter areas of the Southeastern U.S. Yield losses of up to 40 percent have been recorded in some cases in southern wheat growing regions. With no effective agronomic or chemical method of disease control, identification of genetic resistance is seen as a promising solution. Three soft red winter wheat populations (GAWN, ARK-SNP, and AGS 2060- AGS 2035 DH) representative of soft red winter wheat germplasm in the southeastern U.S. developed by …

Precipitation And Not Cover Crop Composition Influenced Corn Economic Optimal N Rate And Yield, Hunter Bielenberg, Jason D. Clark, Debankur Sanyal, Johnathon Wolthuizen, David Karki, Amin Rahhal

Agronomy, Horticulture and Plant Science Faculty Publications

The effects of single species cover crops on corn (Zea mays L.) N requirement and grain yield are well studied throughout the U.S. Midwest. However, comparing cover crop mixes that include different compositions of grass and broadleaf species is limited. Fourteen corn N response experiments were conducted in South Dakota from 2018 to 2021. Fall cover crops planted after small grain harvest were mixtures of dominantly grasses, broadleaves, a 50/50 grass/broadleaf mixture, and a no cover crop control. Compared to the control, including a cover crop led to no differences in economic optimal N rate (EONR) and yield at …

Pestfacts Wa Issue 21 - November 2022, Cindy L. Webster, Ciara Beard, Geoff J. Thomas

PestFacts WA

PestFacts WA Issue 21 - November 2022 contents:

• Final PestFacts WA newsletter for 2022!
• Green bridge management over summer
• PestFacts WA continues successful collaboration with Agworld and Back Paddock

Pestfacts Wa Issue 20 - November 2022, Ciara Beard, Geoff J. Thomas, Dustin Severtson

PestFacts WA

PestFacts WA Issue 20 - November 2022 contents:

• Phomopsis can be a risk when grazing lupin stubble
• Meet PestFacts WA team member – Dusty Severtson

Profit-Maximizing Potassium Fertilizer Recommendations For Corn And Cotton, Kimberly B. Oliver, Michael P. Popp, Nathan A. Slaton, Gerson L. Drescher, Trenton L. Roberts

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Whereas K fertilization is necessary to maximize corn (Zea mays L.) and cotton (Gossypium hirsutum L.) yields in soils with sub-optimum K availability, maximizing yield is rarely profit-maximizing. Estimating the tradeoff between yield and fertilizer cost using current soil-building and/or yield-maximizing rate recommendations vs. profit-maximizing fertilizer-K rates (KR^*) provides insights for producers. Thirty-nine and 24 fertilizer-K rate trials were used to estimate respective corn and cotton yield response based on soil-K availability (SK). Using a field's SK, yield potential, yield response to fertilizer-K, crop price, and fertilizer-K cost, KR^* were calculated over the past 10 …

Historical Corn Price Evolution Implications For Pre-Harvest Hedging, Cory Walters, Richard K. Preston

Cornhusker Economics

Commodity markets evolve through information provided by participating buyers and sellers and throughout this process the conditions in which commodity markets work are revealed. Producer pre-harvest commodity marketing can be further developed by incorporating information on how commodity markets work, leading to better farm financial performance.

We investigate how commodity markets have historically evolved from spring to fall. While changes in future prices appear random in any given year, observing average daily prices over 32 years could uncover a seasonal tendency. In the past 32 years, the average daily price tends to be higher in the spring than the fall, …

Salt Tolerance Qtls Of An Endemic Rice Landrace, Horkuch At Seedling And Reproductive Stages, Taslima Haque, Sabrina M. Elias, Samsad Razzaque, Sudip Biswas, Sumaiya Farah Khan, G. M. Nurnabi Azad Jewel, Md. Sazzadur Rahman, Thomas E. Juenger, Zeba I. Seraj

Department of Agronomy and Horticulture: Faculty Publications

Salinity has a significant negative impact on production of rice. To cope with the increased soil salinity due to climate change, we need to develop salt tolerant rice varieties that can maintain their high yield. Rice landraces indigenous to coastal Bangladesh can be a great resource to study the genetic basis of salt adaptation. In this study, we implemented a QTL analysis framework with a reciprocal mapping population developed from a salt tolerant landrace Horkuch and a high yielding rice variety IR29. Our aim was to detect genetic loci that contributes to the salt adaptive responses of the two …

Microgreens Outreach In The Community - Applying A Novel Diet-Related Disease Prevention Tool, Jessica Nwabeke, Vibhuti Mishra, Rayna Marshall, Simone Udeh, Swaksha Rachuri, Ben Haslund-Gourley, Annette Gadegbeku

Tower Health Research Day

No abstract provided.

Rice Chalky Grain 5 Regulates Natural Variation For Grain Quality Under Heat Stress, Anil Kumar Nalini Chandran, Jaspreet Sandhu, Larissa Irvin, Puneet Paul, Balpreet K. Dhatt, Waseem Hussain, Tian Gao, Paul E. Staswick, Hongfeng Yu, Gota Morota, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Heat stress occurring during rice (Oryza sativa) grain development reduces grain quality, which often manifests as increased grain chalkiness. Although the impact of heat stress on grain yield is well-studied, the genetic basis of rice grain quality under heat stress is less explored as quantifying grain quality is less tractable than grain yield. To address this, we used an image-based colorimetric assay (Red, R; and Green, G) for genome-wide association analysis to identify genetic loci underlying the phenotypic variation in rice grains exposed to heat stress. We found the R to G pixel ratio (RG) derived from mature …

Alfalfa Water Productivity And Yield Gaps In The U.S. Central Great Plains, Kaylin P. Fink, Patricio Grassini, Alexandre Rocateli, Leonardo M. Bastos, Jude Kastens, Luke P. Ryan, Xiaomao Lin, Andres Patrignani, Romulo P. Lollato

Department of Agronomy and Horticulture: Faculty Publications

Context: Yield gap (Yg) analyses using farmer-reported yield and management data have been performed for a number of annual grain crops, but it lacks for perennial forages. The U.S. accounts for 21 % of the global alfalfa production with a large rainfed area located in the central Great Plains, serving as an interesting case-study for Yg in perennial forages. Most existing alfalfa Yg analyses quantified the magnitude of the Yg but failed to identify associated management practices to reduce it. Challenging this analysis, a systematic benchmark for alfalfa water productivity [WP, kg dry matter per mm evapotranspiration (ETc)] that …

Effect Of Water Stress On Weed Germination, Growth Characteristics, And Seed Production: A Global Meta-Analysis, Mandeep Singh, Resham Thapa, Meetpal Singh Kukal, Suat Irmak, Steven Mirsky, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Weeds compete with crops for soil moisture, along with other resources, which can impact the germination, growth, and seed production of weeds; however, this impact has not been systematically recorded and synthesized across diverse studies. To address this knowledge gap, a global meta-analysis was conducted using 1,196 paired observations from 86 published articles assessing the effect of water stress on weed germination, growth characteristics, and seed production. These studies were conducted and published during 1970 through 2020 across four continents (Asia, Australia, Europe, and North America). Imposed water stress was expressed as solution osmotic potential (ψsolution), soil water potential (ψsoil), …

Agronomic And Quality Impact Of A Shortened Translocation For Wheat Streak Mosaic Virus Resistance, Mary J. Guttieri, Robert L. Bowden, Guorong Zhang, Scott Haley, Katherine Anna Frels, Gary L. Hein, Katherine W. Jordan

Department of Agronomy and Horticulture: Faculty Publications

Wheat streak mosaic virus (WSMV) is a mite-vectored virus with substantial economic impact on wheat production. One of the effective sources of resistance to WSMV, Wsm1, is carried on a translocation from Thinopyrum intermedium. The original whole arm form of this translocation (T4DL·4JsS) was highly effective against WSMV but carried a substantial yield penalty in the absence of the virus. Shorter recombinants of the Th. intermedium translocation are now available. This study characterized the agronomic performance of near-isogenic sib-pair families in 10 yield trials using one of these shortened T4DL·4DS-4J^sS translocations, named “rec213,” in the absence …

The Genomic And Bulked Segregant Analysis Of Curcuma Alismatifolia Revealed Its Diverse Bract Pigmentation, Xuezhu Liao, Yuanjun Ye, Xiaoni Zhang, Dan Peng, Mengmeng Hou, Gaofei Fu, Jianjun Tan, Jianli Zhao, Rihong Jiang, Yechun Xu, Jinmei Liu, Jinliang Yang, Wusheng Liu, Luke R. Tembrock, Genfa Zhu, Zhiqiang Wu

Department of Agronomy and Horticulture: Faculty Publications

Compared with most flowers where the showy part comprises specialized leaves (petals) directly subtending the reproductive structures, most Zingiberaceae species produce showy ‘‘flowers’’ through modifications of leaves (bracts) subtending the true flowers throughout an inflorescence. Curcuma alismatifolia, belonging to the Zingiberaceae family, a plant species originating from Southeast Asia, has become increasingly popular in the flower market worldwide because of its varied and esthetically pleasing bracts produced in different cultivars. Here, we present the chromosome-scale genome assembly of C. alismatifolia ‘‘Chiang Mai Pink’’ and explore the underlying mechanisms of bract pigmentation. Comparative genomic analysis revealed C. alismatifolia contains a …

Key Issues Generated From The Xi International Rangeland Congress 2021: Summary And Way Forward, D. L. Coppock, A. J. Ash, B. Irving

IGC Proceedings (1977-2023)

The important issues, knowledge gaps, and evolving research approaches for the global rangelands are summarised in this review of submissions to the Joint XXIV International Grasslands and XI International Rangelands Congress (IGC/IRC). In the big picture, it is concluded that stand-alone studies of livestock production are becoming rare compared to that of the past International Rangelands Congresses (IRC). Rather, added effort is now being directed at understanding the fuller context of social-ecological systems (SESs) on rangelands in a quest to improve the prospects for sustainable resource management as well as the enhancement of human welfare. Although climate change is upon …

Joint International Grassland And International Rangeland Congress Kenya 2021: Grasslands Summary, James L. Klotz, J. H. Bouton

IGC Proceedings (1977-2023)

This summary used as its main sources the plenary and keynote papers and talks in Sub-theme 2: Forage Production and Utilization and Sub-theme 3: Livestock Production Systems as well as a sampling of oral talks presented at the XXIV International Grassland Congress (IGC). This IGC was held virtually and jointly with the International Rangeland Congress and hosted in Nairobi, Kenya during 23-29 October 2021. The XXIV IGC was also the first to be held on the African continent in Congress' 94-year history. The summary is further focused on that information presented under the concept "cultivated grasslands" (e.g., a small number …

2023 Western Australian Crop Sowing Guide, B. Shackley, B. Paynter, J. Bucat, M. Seymour, H. Dhammu

Bulletins 4000 -

Welcome to the 2023 edition of the Crop Sowing Guide for WA, which introduces 31 new variety releases: two wheat, seven barley (one as feed only and six currently under malt evaluation), 15 canola, three hay-only oat and four lentil varieties.

The Crop Sowing Guide for WA has been compiled by officers in the Department of Primary Industries and Regional Development. It provides information to support variety decisions for each of the major crops for the upcoming season.

In this edition, the canola NVT series are now identified by GRDC/NVT as ‘Low-Med Rainfall’ and ‘Med–High Rainfall’ to reflect the environments …

Pestfacts Wa Issue 18 - October 2022, Cindy L. Webster, Svetlana Micic, Alan Lord, Ciara Beard, Andrea Hills, Daniel Huberli

PestFacts WA

PestFacts WA Issue 18 - October 2022 contents:

• Avoid snail contamination in wheat
• Be mindful of chemical withholding periods if spraying for native budworm
• Glume blotch and false (pseudo) black chaff in wheat
• Powdery mildew found in canola and lupin
• Rhizoctonia bare patches are common this year

Auxin-Based Herbicide Program For Weed Control In Auxin Resistant Soybean, Joy Amajioyi, Thandiwe Nleya, Graig Reicks, Janet Moriles- Miller, David Clay, Sharon Clay

Agronomy, Horticulture and Plant Science Faculty Publications

Soybean [Glycine max (L.) Merr.] cultivars resistant to synthetic auxin herbicides have provided another mode of action for the postemergence broadleaf weed control. This field study was conducted at three South Dakota locations [Northeast, NERF; east-central, ARF; and Southeast, SERF) in 2019 and two locations (ARF and SERF) in 2020. The Enlist E3 and Roundup Ready 2 Xtend cultivars were planted at three dates (early, mid-, and late season) to examine weed control, agronomic characteristics, nodulation, and yield. Preemergence (PRE) treatment was flumioxazin + metribuzin + S-metolachlor + glyphosate + pendimethalin. Two postemergence (POST) treatments, based on cultivar, were compared …

Herbicide Spray Drift From Ground And Aerial Applications: Implications For Potential Pollinator Foraging Sources, Thomas R. Butts, Bradley K. Fritz, K. Badou-Jeremie Kouame, Jason K. Norsworthy, L. Tom Barber, W. Jeremy Ross, Gus M. Lorenz, Benjamin C. Thrash, Nicholas R. Bateman, John J. Adamczyk

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

A field spray drift experiment using florpyrauxifen-benzyl was conducted to measure drift from commercial ground and aerial applications, evaluate soybean [Glycine max (L.) Merr.] impacts, and compare to United States Environmental Protection Agency (US EPA) drift models. Collected field data were consistent with US EPA model predictions. Generally, with both systems applying a Coarse spray in a 13-kph average wind speed, the aerial application had a 5.0- to 8.6-fold increase in drift compared to the ground application, and subsequently, a 1.7- to 3.6-fold increase in downwind soybean injury. Soybean reproductive structures were severely reduced following herbicide exposure, potentially negatively …

Cyclic Adp Ribose Isomers: Production, Chemical Structures, And Immune Signaling, Mohammad K. Manik, Yun Shi, Sulin Li, Mark A. Zaydman, Neha Damaraju, Samuel Eastman, Thomas G. Smith, Weixi Gu, Veronika Masic, Tamim Mosaiab, James S. Weagley, Steven J. Hancock, Eduardo Vasquez, Lauren Hartley-Tassell, Nestoras Kargios, Natsumi Maruta, Bryan Y.J. Lim, Hayden Burdett, Michael J. Landsberg, Mark A. Schembri, Ivan Prokes, Lijiang Song, Murray Grant, Aaron Diantonio, Jeffrey D. Nanson, Ming Guo, Jeffrey Milbrandt, Thomas Ve, Bostjan Kobe

Department of Agronomy and Horticulture: Faculty Publications

Cyclic adenosine diphosphate (ADP)–ribose (cADPR) isomers are signaling molecules produced by bacterial and plant Toll/interleukin-1 receptor (TIR) domains via nicotinamide adenine dinucleotide (oxidized form) (NAD+) hydrolysis. We show that v-cADPR (2′cADPR) and v2-cADPR (3′cADPR) isomers are cyclized by O-glycosidic bond formation between the ribose moieties in ADPR. Structures of 2′cADPR-producing TIR domains reveal conformational changes that lead to an active assembly that resembles those of Toll-like receptor adaptor TIR domains. Mutagenesis reveals a conserved tryptophan that is essential for cyclization. We show that 3′cADPR is an activator of ThsA effector proteins from the bacterial antiphage defense system termed Thoeris and …