The induction of stress-related factors in plants

The present invention relates to a method of producing resistance to stress in a variety of plants by the expression of a hydrogen peroxide or reactive oxygen species producing enzyme such as, but not limited to, oxalate oxidase. In addition, the present invention relates to a method of producing a stress resistant sunflower plant by transforming a sunflower plant with an oxalate oxidase gene or other hydrogen peroxide/reactive oxygen species producing genes that upon expression of the gene produce an enzyme capable of generating hydrogen peroxide or reactive oxygen species from endogeously available substrate. Alternatively, the plant could be transformed with the hydrogen peroxide or reactive oxygen species producing gene and a gene for the necessary substrate or a gene which would modify a pathway in the plant resulting in formation or increase in substrate. The production of hydrogen peroxide or a reactive oxygen species triggers the expression of hydrogen peroxide/reactive oxygen species-responsive genes resulting ina pre-challenge accumulation of pathogenesis or stress-related factors such as salicylic acid and PR protein. Thus the plant is rendered resistant to a variety of stresses by, for example, inhibiting the establishment of a pathogen resulting in a disease resistance phenotype.