The University of Kentucky is initiating an herbicide resistance screening program (HRS) to assist crop producers in Kentucky. The goal of the program is to assist growers in determining if the lack of efficacy in herbicides is due to resistance developing in a weed species or possibly caused by an environmental event or application issue. Spraying herbicides when resistance is present can be a waste of valuable time and money. Additionally, while specific information on farms will be kept private, obtaining herbicide resistant samples will allow for researchers at the University of Kentucky to determine the causes of herbicide resistance and begin to develop long-term solutions for growers. To submit samples, follow these instructions:
1. Identify plants that were not killed/suppressed by an herbicide but should have been, based on the product label and/or Weed Control Recommendations for Kentucky Grain Crops (AGR-6). Consult with your County Extension Agent and State Extension Weed Specialist to determine the likelihood of resistance event versus a failed application. Weed species of interest include Italian Ryegrass (Lolium multiflorum), Johnsongrass (Sorghum halepense), Horseweed (Conyzacanadensis), Water-hemp (Amaranthus tuberculatus), Palmer Amaranth (Amaranthus palmeri) and Giant Ragweed (Ambrosia trifida). Consult your county extension agent before submitting other species
2. Cut of 10 seed heads with at least 10 mature seeds on each of them from separate plants (we will also take rhizomes of johnsongrass plants) and place them in the pre-stamped envelope. Pre-stamped envelopes can be obtained from your local county extension agent. If you cannot fit all ten seed heads in the envelopes, place as many as you can fit into the envelope.
3. Samples, contact information, and herbicide application history should be submitted to the Adair County Cooperative Extension Service. Seeds submitted will be germinated and grown in a greenhouse environment to test herbicide sensitivity. Result will be available after 2-3 months.
For more information on herbicide resistance screening services, contact the Adair County Cooperative Extension Service at (270) 384-2317.
Educational programs of Kentucky Cooperative Extension serve all people regardless of economic or social status and will not discriminate on the basis of race, color, ethnic origin, national origin, creed, religion, political belief, sex, sexual orientation, gender identity, gender expression, pregnancy, marital status, genetic information, age, veteran status, or physical or mental disability.
