Early history and significance of the peanut crop is discussed. Annual world production of peanuts at 30 million tons makes this crop one of the most important agricultural commodities. Unusual physiology, inflorescence, and infructescence of the peanut plant make it an attractive object for scientific research. Many physiological processes in the peanut plant, such as vegetative growth, nitrogen fixation, and fertilisation are associated with light. Present research revealed high light-sensitivity of the spermidines from the peanut reproductive organ, keel.