Gender Differences in Phenotypic Plasticity and Adaptive Response of Seabuckthorn (hippophae Rhamnoides L.) along an Altitudinal Gradient in Trans-Himalaya

BACKGROUND: In dioecious plants, morphological adjustment to climate change may differ between male and female individuals due to greater reproductive effort in females. Not accounting for sexual variation could lead to incorrect assessment of a species response to climate change. OBJECTIVES: The aim of this study was to assess how important gender-specific responses are to Hippophae rhamnoides in changing trans-Himalayan environments. METHOD: Leaf morphological characters of male and female Hippophae rhamnoides individuals along an altitudinal gradient (2797-4117 m) and plants raised in 'common-garden' experiment was measured. RESULTS: Leaves become smaller in length and area, but became thicker with decreasing specific leaf area (SLA) with increasing altitude in both the gender. Leaf size, area, thickness, chlorophyll and petiole length were found to be higher in males than in females, while female had a higher SLA. When cuttings from the plants were grown in a common-garden experiment, the altitudinal effect disappeared for all morphological variables suggesting that most leaf morphological variation in H. rhamnoides is environmentally determined. In the event of climate change, our study showed that phenotypic plasticity would be a crucial determinant of plant response in mountainous region. Effect of altitudinal gradient on leaf morphology was more conspicuous in males suggesting that males are more responsive to change in environmental conditions. CONCLUSION: The results suggested that males will adapt better to the changing climate and may lead to a male-biased population in the event of climate change. Stressful environments cause added detrimental impact on female than on male.