The present invention is directed to methods for inhibiting the growth of disease organisms, particularly fungi and bacteria, on plant tissues. The present invention is also directed to methods for inhibiting the infestation of plants by insects and larva, particularly sucking and chewing insects. These methods are achieved by applying an auxin or a plant growth regulator (PGR) which will effect the level of auxin in the plant tissue to the seeds or tubers of the plant prior to planting or to the roots, foliage, flowers or fruit of the plant after planting.
