Potato, solanum tuberosum L. is a major food crop in many countries of the world including Egypt. The production of this crop is already expanded to relatively warm and humid regions that are suitable to the survival and development of several pathogenic pests, including nematodes. Such improvement has come mainly from certain fertilizer applications, higher yielding varieties, and better methods of controlling weeds, pests and diseases such as nematodes as well as improve plant growth by certain chemical regulation i.e. growth regulators. Moreover, such growth regulators i.e. IAA or GA3, can alter the distribution of dry matter within this plant so as to increase the economic yield and to enable the plant to adapt the adverse conditions to the degree that alter a plant growth in away which virtually convert in into another variety. Meanwhile, some evidence has been gathered that the control of plant growth by chemical regulation not only influences plant growth and its yield but also the chemical composition of the treated plants, as well as tubers produced and induced resistance against such attacking pathogenic nematodes.