Mitigating Insect Herbivory of Warm-Season Bioenergy Grasses – Getting Ahead of the Curve
Grain, Forage & Bioenergy Research
Project Number: 5440-21000-030-04
Start Date: Feb 01, 2011
End Date: Jan 31, 2016
Sustainable production of switchgrass and other bioenergy grasses will require effective pest management. Currently we know little about the potential insect pests of the tetraploid switchgrass genotypes that are being developed as bioenergy cultivars for the Central USA. Our prior experience with greenbug-sorghum and chinchbug-turfgrasses interactions indicates that insect pests will eventually emerge on switchgrass fields. Identification of potential insect pests and detailed characterization of the plant-insect interaction will better enable us to address emergent insect pests in switchgrass production fields. Additionally, it is unclear how manipulation of plants for improved quality (for example lower lignin) will affect plant resistance to insect herbivory. Our collaborative team has recently identified the yellow sugarcane aphid, chinch bugs, and greenbugs as potential pests of switchgrass. With our combined expertise in plants and insects, we are uniquely positioned to provide significant new information that will serve as the foundation for long-term sustainable pest management strategies. The research goals of this 5 year project are to identify plants with enhanced resistance to sucking insects using defined populations of switchgrass, improve our understanding of the mechanisms, genes, proteins and metabolites contributing to the resistance, and develop sustainable pest management strategies through endogenous plant resistance. Our long-term research goals are to significantly impact the development of bioeneregy grasses with enhanced resistance to biotic stress that offer improved environmental safety and reduce human health risks.
1: Develop efficient phenotyping tools for insect resistance of switchgrass and other tall perennial grasses.
2: Understand insect resistance mechanisms among defined switchgrass populations.
3: Obtain biochemical, physiological and anatomical insights into insect-bioenergy grass interactions.
4: Define transcriptional and metabolic changes occurring in switchgrass genotypes with varying levels of insect resistance.
5: Utilize methods in RNA profiling of insects to uncover key transcriptional regulatory mechanisms that govern host range in grass-feeding insects.
We will take defined populations of switchgrass and investigate plant and insect responses with a wide array of complementary tools, including characterization of the resistance responses using antixenosis, antibiosis, and tolerance methodologies. Functional genomic tools will be used to define biochemical, physiological, metabolic and molecular plant defense mechanisms, and take advantage of existing switchgrass molecular resources and the pending release of a draft version of the switchgrass genome, and exploit its synteny with sorghum to identify potential genes. Traditional and molecular methods such as high-throughput DNA sequencing will be used to decipher fitness parameters for the different insects.