The effect of salinity on growth, photosynthetic pigment content, and alkaloid secondary metabolite accumulation were studied in an economically important medicinal plant, Catharanthus roseus (L.) G. Don., under pot culture conditions. Plants were treated with different concentrations of NaCl, (. 50 and 100 mM) 30, 45, 60, and 75 days after sowing (DAS). | Turk J Biol 32 (2008) 79-83 © TÜB‹TAK Soil Salinity Alters Growth, Chlorophyll Content, and Secondary Metabolite Accumulation in Catharanthus roseus Cheruth Abdul JALEEL, Beemarao SANKAR, Ramalingam SRIDHARAN, Rajaram PANNEERSELVAM Stress Physiology Lab, Department of Botany, Annamalai University, Annamalainagar 608 002, Tamil Nadu - INDIA Received: Abstract: The effect of salinity on growth, photosynthetic pigment content, and alkaloid secondary metabolite accumulation were studied in an economically important medicinal plant, Catharanthus roseus (L.) G. Don., under pot culture conditions. Plants were treated with different concentrations of NaCl, (. 50 and 100 mM) 30, 45, 60, and 75 days after sowing (DAS). The plants were uprooted randomly 90 DAS to analyse growth, and chlorophyll and alkaloid content. Salinity affected all the morphological parameters and decreased growth performance. At low salinity regimes, a slight decrease was noted in chlorophyll a and b, and total chlorophyll content, but under high salinity conditions a significant reduction in the content of these pigments was observed. The chlorophyll a:chlorophyll b ratio also varied significantly under salinity stress. Alkaloid content increased under saline soil conditions. Key Words: Catharanthus roseus; growth; chlorophyll; salinity; alkaloid Catharanthus roseus Bitkisinde Toprak Tuzlulu¤unun Büyüme, Klorofil Miktar› ve ‹kincil Metabolit Birikimi Üzerine Etkisi Özet: Ekonomik öneme sahip Catharanthus roseus (L.) t›bbi bitkisinin büyüme, fotosentetik pigment muhtevas› ve alkoloit ikincil metabolit birikimi üzerinde tuzlulu¤un etkisi çal›fl›lm›flt›r. Bitki tohumlar› 50 ve 100 mM l›k tuz ile muamele edilmifl ve tohumlar ekildikten sonra 30, 45, 60, 75 gün aral›klarla deiyonize suyla sulanm›flt›r. 90 günlük bitkiler al›narak büyüme, klorofil ve alkoloit muhteva analizi yap›lm›flt›r. Tuzlulu¤un bütün morfolojik parametreleri etkiledi¤i ve büyüme performans›n› azalt›¤› gözlenmifltir. .
