Seasonal variation in physiology of Eucalyptus genotypes in relation to soil salinity

Expanding problems of soil salinity has become serious issues of concern as it affects productivity and threatens the sustainability of wood production by forest trees. An experiment was conducted to test the ability of Eucalyptus trees to grow under saline environment and to maintain their physiology. Saline irrigation treatment of five levels (Control, 5 dSm-1, 10dSm-1, 20 dSm-1and 40 dSm-1) were applied, eventually two highest levels viz., 20 dSm-1and 40 dSm-1 leads to death of seedlings of three genotypes of Eucalyptus tereticornis (C-288), E. camaldulensis (C-413) and Eucalyptus hybrid (C-2070). As the salinity level increases, physiological processes were started declining more in all genotypes as compare to control condition. In general, genotype C-413 was found to be best for all physiological processes studied during winter season and water use efficiency and chlorophyll content during summer season, whereas, genotype C-2070 was best for photosynthesis, transpiration during summer season.