Location: Forage-animal Production Research
Project Number: 5042-21500-001-000-D
Project Type: In-House Appropriated
Start Date: Jan 17, 2024
End Date: Jan 16, 2029
Objective:
Objective 1: Improve the management and use of tall fescue and red clover through improved understanding of the natural products used as signals between the plant and symbiotic microbes, and the impact of climate on these interactions.
Subobjective 1.A: Assess the genetic and physiological basis for non-toxic endophyte stability, transmission and enhanced plant stress tolerance in tall fescue.
Subobjective 1.B: Assess the response of red clover in field settings in induced environmental change plots to predict responses to climate changes.
Subobjective 1.C: Develop tools to characterize and promote novel expression systems in red clover for improved plant persistence and nitrogen fixation.
Objective 2: Characterize plant primary metabolites and determine their roles in sustainable animal health and performance.
Subobjective 2.A: Evaluate ruminant species (ovine and bovine) differences in rumen-utilization of different carbohydrate sources as it relates to microbial community composition and function.
Objective 3: Determine how plant secondary metabolites can help improve pasture sustainability, enhance animal health and performance, and decrease animal environmental footprint.
Subobjective 3.A: Profile nutritive values and isoflavone concentrations in multiple forage legume species and identify correlations with species/variety, plant characteristics (maturity, plant part, physical characteristics), and seasonal/environmental impacts.
Subobjective 3.B: Investigate the role of isoflavone metabolites in pastures on soil microbial processes.
Subobjective 3.C: Identify phenolic compounds in cool-season grasses and phenolic or terpenoid compounds in industrial hemp inhibiting ruminal bacteria that cause nitrogen loss.
Objective 4: Improve hemp genetic, agronomic and physiological characteristics favorable to a pasture-based economy and explore secondary metabolites for benefits to animal performance.
Subobjective 4.A: Assemble and integrate current hemp related data from field experiments, seed quality and planting requirements and cultivar evaluations for development of best management practices (BMPs).
Subobjective 4.B: Develop a method for extracting and quantifying mycotoxins from hemp infected with Fusarium graminearum.
Subobjective 4.C: Evaluate the impact of hemp on silage-spoilage bacteria.
Subobjective 4.D: Investigate the potential secondary metabolite impacts, namely, cannabinoids, terpenes, and isoflavones found in hemp on rumen tissue from ruminant livestock.
Approach:
Experiments conducted to determine the changes in endophyte gene expression during infection of the ovary by comparing expression inflorescence primordial & ovary tissues to vegetative tissues, the lemma & palea of young florets & pseudostems (Ob. 1A). Experiments conducted to determine the effect of reactive oxygen species (ROS) during endophyte colonization of host ovaries & ovules using fluorescent tagged proteins to monitor expression (Obj 1A). Determine compatibility of 8 non-toxic producing endophyte strains with the Continental tall fescue variety by following endophyte transmission under field conditions using seed staining & immunoblot approaches (Obj 1A). Evaluate the effect of stress on the transmission of different endophyte strains under heat stress (Obj 1B). Growth, seed set & alkaloid production of different endophyte strains under stress conditions in the field will be conducted. Assess the relationship between pasture botanical composition & the ratio of cool season & warm season grasses of on-farm experiments during four years & correlate with changes observed from satellite imagery over longer time to provide producers with a measure of the change from cool season to warm season for the transition zone (Obj 1C). Stability of isoflavones in storage evaluated by sampling fresh & field-cured (hay) material over time & under different drying & storage conditions (Obj 2A). Excreta from lambs or steers fed isoflavones or hops beta-acids evaluated for greenhouse gas emission (Obj 2B). Bioassay-guided fractionation applied to extracts of phenolic compounds from Lolium perenne to identify specific metabolites inhibiting ruminal hyper-ammonium-producing bacteria (Obj 2C). Isoflavone concentrations & profiles evaluated in clovers mutated in the isoflavone biosynthetic pathway (Obj 2D). Fructan concentrations & profiles determined in several cool-season grasses, & effects on growth of various ruminal bacteria (both mixed & pure cultures) assessed (Obj 3A). Lignin & arabinoxylan extracted from those cool-season grasses & a warmseason grass (Obj 3B). Effects of lignin & arabinoxylan profiles & concentrations on ruminal & equine hindgut bacteria characterized (Obj 3B). Mineral leaching compared from feces of steers & horses fed hay or grain diets (Obj 3C). Mineral leaching compared from feces of horses fed hay with a low or high fructan content (Obj 3C). Characterize the mode of action for 2-4D resistance in red clover using a whole genome transcription approach to identifying differences between susceptible & resistant germplasm (Obj 4A). Characterize red clover growth parameters, N-fixation & whole genome transcription as affected by heat stress under field conditions (Obj 4B). Gene knock-out experiments will be conducted using the CRISPR/Cas9 system to genes known to affect root morphology & interaction with rhizobium explore interaction of red clover with different rhizobial strains (Obj 4C). Alternate polyadelynation will be evaluated to determine how alternative RNA processing that results in different protein products affects nodulation & nitrogen fixing efficiency (Obj 4C).
