Correlations between allocation to foliar phosphorus fractions and maintenance of photosynthetic integrity in six mangrove populations as affected by chilling.csv

●Chilling restrains the distribution of mangroves. We tested whether foliar phosphorus (P) fractions and gene expression are associated with cold tolerance in mangrove species.●We exposed seedlings of six mangrove populations from different latitudes to favorable, chilling and recovery treatments, and measured their foliar P concentrations and fractions, photochemistry, night-time respiration, and gene expression. ●A Kandelia obovata (26.45ºN; KO) population completely and a Bruguiera gymnorhiza (21.50ºN; BGG) population partially (30%) survived chilling. Avicennia marina (24.29ºN), and other B. gymnorhiza (26.66ºN, 24.40ºN and 19.62ºN) populations died after chilling. Photosystems of KO and photosystem I of BGG were least injured. Following chilling, leaf P fractions, except nucleic acid P in three populations declined, and photoinhibition and night-time respiration increased in all populations, with the greatest impact in B. gymnorhiza. Leaf nucleic acid P was positively correlated with photochemical efficiency during recovery and night-time respiration across populations for each treatment.●Relatively high concentrations of nucleic acid P and metabolite P were associated with stronger chilling tolerance in K. obovata. Bruguiera gymnorhiza exhibited relatively low concentrations of organic P in favorable and chilling conditions, but its partially survived population showed stronger compensation in nucleic acid P and Pi concentrations and gene expression during recovery.