%0 Journal Article %T Effect of supplemental Ca2+ on NaCl-stressed castor plants (Ricinus communis L.) %A Seema V. Joshi %A Neha T. Patel %A Indu B. Pandey %A Amar Nath Pandey %J Acta Botanica Croatica %D 2012 %I University of Zagreb %R 10.2478/v10184-011-0061-6 %X Greenhouse experiments were conducted to assess the effects of supplemental Ca2+ in salinised soil on germination and plant growth response of castor plant (Ricinus communis L. Var. Avani-31, Euphorbiaceae). NaCl amounting to 390 g was thoroughly mixed with soil of seven lots, of 100 kg each, to give electrical conductivity of 4.1 dS m-1. Further, Ca(NO3)2 x 4H20 to the quantity of 97.5, 195, 292.5, 390, 487.5, and 585 g was separately mixed with soil of six lots to give 1:0.25, 1:0.50, 1:0.75, 1:1, 1:1.25, and 1:1.50 Na+/Ca2+ ratios, respectively. The soil of the seventh lot contained only NaCl and its Na+/Ca2+ ratio was 1:0. Soil without addition of NaCl and Ca (NO3)2 x 4H20 served as control, with a 0:0 Na+/Ca2+ ratio. Salinity significantly retarded seed germination and plant growth, but the deleterious effects of NaCl on seed germination were ameliorated and plant growth was restored with Ca2+ supply at the critical level (1:0.25 Na+/Ca2+ ratio) to salinised soil. Supply of Ca2+ above the critical level further retarded seed germination and plant growth due to the increased soil salinity. Salt stress reduced N, P, K+ and Ca2+ content in plant tissues, but these nutrients were restored by addition of Ca2+ at the critical level to saline soil. In contrast, Na+ content in plant tissues significantly increased in response to salinity, but significantly decreased with increasing Ca2+ supply to saline soil. The results are discussed in terms of the beneficial effects of Ca2+ supply on the plant growth of Ricinus communis grown under saline conditions. %K Na+/Ca2+ ratio %K Ricinus communis %K seedling growth %K salt tolerance %K salt stress %U http://versita.metapress.com/content/p236pn4730114218/?p=2830fa6510634d069ed3d9b38b8d9706&pi=1