Abstract: Methods for treating a plant comprise contacting a plant or a part of a plant with one or more of 9-oxononanoic acid, arachidonic acid, or a salt or ester thereof; wherein the amount is effective to increase tolerance to abiotic stress in the plant or to reduce a consequence of abiotic stress in the plant. Additional ingredients can be included such as dicarboxylic acids, pipecolic acid, or salicylic acid, or salts/esters thereof; sunblocks such as kaolin or calcium carbonate; carriers such as inert powders or liquids; and co-treatment materials such as fertilizers, plant nutrients, biostimulants, micronutrients, amino acids, plant hormones, pesticides, fungicides, insecticides, nematicide, stearic acid, vegetable oil, or phospholipid.