Seasonal variations in leaf macro and micronutrient composition of plum cv. Santa Rosa

Seasonal variations in leaf nutrient composition of plum cv. Santa Rosa were studied at 15 days interval, starting from May 1 to September 1, 2009–10. The results revealed that the variations in leaf nutrient contents occurred throughout the growing season. Leaf content of N and K increased early in the growing season, reach highest value on June 15, and thereafter decreased significantly with the advancement in growing season. Leaf P and Zn contents exhibited a decreasing trend throughout the growing period. Whereas, Ca, Mg and Fe content followed reverse trend and increased throughout the growing season. However, Cu content of plum leaves increased in the beginning of the sampling period, reached a highest value on June 15 and declined thereafter and reached its lowest value on September 1. A nutrient stability period from June 15 to July 15 was for N, P, K and Ca and between July 1 to July 15 for Zn and Cu. whereas, for Mg and Fe, nutrient stability period was observed between June 1 to June 15 and August 1 to August 15, respectively. These nutrient stability periods can be used to sample leaves for diagnostic purpose.