Pea (Pisum sativum) leaves grown under high and low iiradiances were exposed for 6 h to a limiting, saturating oř excessive irradiance. The tůně courses of synthesis of the photosystem 2 (PS 2) core proteins D2 and CP43 and CP47 were studied. The D2 protein synthesis characteristics were shown to be dependent on both the growth irradiance and the irradiance during synthesis, reflecáng long-term and short-term adjustments of the plant. CP43 and CP47 synthesis was less susceptible to alterations in irradiance.