Chlorophyll content and its stability in native species inhabiting the Egyptian Desert

Characteristics of chlorophyll (Chl) among species growing in desert areas receiving high intensities of insolation were investigated. Generally, chlorophyll content in xerophytes is low; perennials, except succulents and halophytes, have higher contents than annuals. This decreased Chl content is compensated for by an increased Chl stability index (CSI). Moreover, the difference between the Chla/bratio in fresh and heated leaves is decreased in plants with a high CSI, where a positive difference refers to destruction of Chlaand a negative difference to destruction of Chlb.A significant correlation between both Chl content and CSI with water content, soluble proteins, Mg2+, K+and iron was found, with the sign of the correlation dependent on the importance of the constituents to Chl content and CSI in the studied species.