Effect of Water Stress on Pigment Formation in Quercus Species

The effect of water stress in three Quercus species belonging to different habitats is investigated. Chlorophyll concentration decreased in all Quercus species with the greatest decrease occurring in Quercus robur. An increase of total carotenoid content was observed in Quercus coccifera and Quercus ilex, while in Q. robur water stress effected a carotenoid content reduction. Anthocyanins increased with decreasing relative water content in the three Quercus species, the largest increase occurring in Q. coccifera. A correlation between xerophytic character and pigment concentration is discussed.