Ortets selected from polyclonal seedling plantations raised in five different regional stations of RRII were planted at Nagrakata in sub-Himalayan West Bengal in order to evaluate their performance under cold stress. Early establishment and growth in the field as well as maximum (Fv/Fm) and effective(Q PSII) quantum yield of PSII during post monsoon, pre-winter and post winter period were measured. Among the ortets tested, growth was better for the ortets collected from Guwahati. The survival of leaves at the top whorl was highest for the ortets RRSD 1 and lowest for RRSA 98. The magnitude of depression in Fv/Fm from post-monsoon to pre-winter was the lowest in RRSD 1. The study indicated that based on initial establishment and chlorophyll fluorescence parameters, RRSD 1 would be a highly potential cold tolerant ortet and RRSA 98 was found to be a highly susceptible ortet in the prevailing cold climate of sub-Himalayan West Bengal.