The research focus of Prof. Nafees A. Khan is on the identification of strategies for developing abiotic stress tolerant crop plants through modulation of tolerance mechanism, and strengthening positive source-sink relationship under optimal and limited environmental conditions. The key observations and recommendations showed that the potential of adverse effects of abiotic stress factors (salinity, drought, heat and metals) could be reduced by judicious synergism with signalling molecules for maximizing the use-efficiency of primary mineral nutrient elements and establishing a cross-talk. He found that the use of the signalling molecules enhances the use-efficiency of primary nutrient elements that results in the increased efficiency of enzymatic and non-enzymatic antioxidants. The overall effect was seen in the increased potential of photosynthetic machinery and abiotic stress tolerance with enhancement in the crop productivity under stressful environments. These research findings have been reported in Plant Physiology, Plant, Cell & Environment, Journal of Experimental Botany, Frontiers in Plant Science, Physiologia Plantarum, Ecotoxicology and Environmental Safety, Environmental and Experimental Botany, Journal of Plant Physiology, Plant Physiology and Biochemistry, Protoplasma, Nitric Oxide, Plant Science, BMC Plant Biology, Journal of Plant Growth Regulation, Photosynthetica, Journal of Agronomy and Crop Science, Field Crops Research, Antioxidants, Biomolecules and others.