Ecological role of distinct fruit-wing perianth color in synchronization of seed germination in Haloxylon salicornicum ARVIND BHATT,* SHYAM S PHARTYAL†‡ and ASHLEY NICHOLAS§ *Gulf Organization for Research and Development, Qatar Science and Technology Park, 10162, Doha, Qatar, †Department of Forestry and Natural Resources, HNB Garhwal University, 246174, Srinagar-Garhwal, India, ‡Institute of Plant Science, University of Regensburg, Universitäts Street 31, 93053, Regensburg, Germany; and §School of Life Science, Westville Campus, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa Abstract Haloxylon salicornicum is a perennial shrub that grows in sandy and stony desert areas. This species produces two types of dispersal unit with yellow and pink winged peri- anths that are wind dispersed. This species has been considered as an excellent sand binder and can tolerate extreme temperature, drought and salinity. We compared the germination characteristics of both colored dispersal units (with and without a wing) under various light, temperature and salinity treatments. It was found that wing color, presence of wings, temperature and light have a significant effect on germination per- centage and germination rate. The presence of a winged perianth significantly reduced the germination percentage and germination rate in both yellow and pink dispersal units. De-winged yellow dispersal units were able to tolerate higher salinity and, there- fore, their germination was higher in all the tested concentrations of NaCl compared with pink de-winged dispersal units. However, salinity tolerance in both pink and yel- low dispersal units decreased with increasing salinity concentration. The germination- recovery percentage was also higher for yellow compared with pink dispersal units. The present study has demonstrated that both morphological and physiological differences exist in different colored dispersal units, which might represent the combination of dif- ferent complementary adaptive strategies and have ecological significance for Haloxylon salicornicum’s successful survival in harsh desert environmental conditions. Keywords: germination, Haloxylon salicornicum, perianth color, salinity tolerance, temperature. Received 5 October 2015; revision received 5 February 2016; accepted 24 March 2016 Introduction The climate of the Arabian Peninsula is characterized by extremely high temperature, low unpredictable rainfall and high evaporation rates (Ragab & Prudhomme 2002). Further, most of the area of the Arabian Peninsula is vul- nerable to desertification due to its extreme aridity and degradation of soil and vegetation caused by human activity. In addition, high levels of soil and saline water exacerbate the challenges for plants growing under desert conditions (Khan & Weber 2006). Therefore, most desert plant species have evolved several adaptive char- acteristics, such as variation in seed size and color, and the presence of special dispersal structures and strategies that help them to survive under such harsh environmen- tal conditions (Wei et al. 2007; Chang et al. 2008; El-Keblawy et al. 2013). The production of dimorphic or heteromorphic diaspores is one of the most effective stra- tegies for adaptation and for increasing the reproductive success of desert plants under unpredictable climatic con- ditions (Imbert 2002). These phenotypic differences in seed-shape, mass and color have been shown to cause differences in dispersal, germination characteristics, Correspondence: Arvind Bhatt Email: drbhatt79@gmail.com © 2016 The Society for the Study of Species Biology Plant Species Biology (2016) doi: 10.1111/1442-1984.12133