Development in plants is under the control of intrinsic factors only.
Development broadly is considered as the sum of growth and differentiation.
Growth, differentiation and development are very closely related events in the life of a plant.
Development is a term that includes all changes that an organism goes through during its life cycle from germination of the seed to senescence.
Development in plants (i.e., both growth and differentiation) is under the control of intrinsic and extrinsic factors. The former includes both intracellular (genetic) or intercellular factors (chemicals such as plant growth regulators) while the latter includes light, temperature, water, oxygen, nutrition, etc.