Role of calcium in alleviating effect of salinity on germination of Phragmites karka seeds

摘要: Abstract Phragmites karka (Retz.) Trin, ex. steud, a perennial reed with creeping rhizome from the family Poaceae, is distributed as pure population in brackish water swamps. Populations primarily propagate using ramets but also produce numerous seeds which form part of seed bank after dispersal and are exposed to extremes temperature, drought, salinity stress. Seeds were germinated under range (0, 100, 200, 300, 400, 500 mM NaCl) temperature (10/20 °C, 15/25 °C, 20/30 °C, 25/35 °C, night/day) regimes 12 h light:12 h dark photoperiod or complete darkness 0, 5, 10, 25 mM CaCl 2 . Salinity, absence light high (25/35 °C) reduced germination while calcium generally reversed this effect, more so at cooler regimes. Calcareous soil around Karachi would help alleviate effect on P. facilitate its survival.