EFFECT OF DIFFERENT LEVELS OF SALINITY ON GROWTH PERFORMANCES OF SOME SELECTED TREE SPECIES

Abstract

Tsunami was the worst disaster happened to coastal region of Sri Lanka. Dueto tsunami, salinity levels were increased in affected areas, therefore selectionof salt tolerant tree species are timely important. But the studies conducted onselection of suitable salt tolerant timber species are rather limited. So thisstudy was conducted to select four suitable salt tolerant species in tsunamiaffected areas.

Four separate pot experiments were conducted at the faculty of AgricultureUniversity of Ruhuna, Mapalana during mid May to October 2005 to studythe effect of different levels of salinity (0.13, 2, 4, 6, 8, 12 mscm -1) ongrowth performances of four selected tree species (Melia azedarach.Artocarpus heterophyllus, Swietenia mahogany, and Accacia mangium). Theexperimental design was RCBD with 10 replicates. Six-month-old seedlingsof each species were used for the experiment. After root establishment,treatments were started. Number of leaves, plant height, were measured twoweeks intervals by non-destructive method, and total fresh weight, totalbiomass yield, number of roots were measured in once a month bydestructive method. Data were statistically analyzed by using ANOV A andmeans were separated by using DMRT.

According to the study, Melia asedarach, Swietenia mahogany, Accasiamangium are suitable for tsunami-affected areas. Salinity level tolerance ofMelia azedarach, artocarpus heterophyllus, Swietenia mahogany, and Acaciamangium are 4 ms/cm, 0.13 ms/cm, 8ms/cm, and 12ms /cm respectively.Normal soil salinity level 0.46ms/cm. Levels of salinity 6ms/cm is the bestfor Accasia among the treatments. Level of salinity 2ms/cm is the best for theMelia azedarach among the treatments. Normal salinity level of soil (0.46ms/cm) gives the best performances for Artocarpus heterophyllus andSwietenia mahogany.