Chemical Science Review and Letters ISSN 2278-6783 Chem Sci Rev Lett 2017, 6(23), 1537-1543 Article CS092048062 1537 Research Article Mechanisms and Strategies for Improving Drought Tolerance in Fruit Crops Anjali Soni 1 *, Poonam Kumari 2 , Sunita Dhakar 2 and Neeraj Kumar 3 1 Division of Fruits and Horticultural Technology, ICAR- Indian Agricultural Research Institute, New Delhi 110 012, India 2 Division of Floriculture and Landscaping, ICAR- Indian Agricultural Research Institute, New Delhi 110 012, India 3 Division of Genetics, ICAR- Indian Agricultural Research Institute, New Delhi 110 012, India Introduction Globally biotic and abiotic stresses are the serious threat to food security and India will be among the worst affected countries considering its large population under below poverty line. Abiotic stress under the climate change scenario will adversely affect the perennial horticultural crops. Drought and salinity are among the major abiotc stresses that affect 1/3 rd global population in terms of human health and farm productivity [1]. Because the world‟s water supply is limiting, future food demand for rapidly increasing population pressures is likely to further aggravate the effects of drought. Agricultural drought addresses the situation in which the water available to the plants through rainfall and/or irrigation is insufficient to meet the transpiration needs of the crop, which leads to yield reductions [2]. The agricultural drought will differ between crops because of two major factors (crop water demand and crop water supply) [3]. Climatic factors such as high temperature, high wind velocity and low relative humidity are associated with drought. Basically there are two types of drought-atmospheric drought and soil drought. The severity of drought is unpredictable as it depends on many factors such as occurrence and distribution of rainfall, evaporative demands and moisture retaining capacity of soils. Drought tolerance is a very complex trait as it depends not only on the severity of the drought (mild or severe), but also on the developmental stage of the plant as well as the duration [4, 5]. From the physiological point of view, survival is the major aim in plant stress tolerance, whereas from the agricultural point of view crop yield is the trait that determines a drought tolerant crop [6]. Drought stress causes a wide range of morpho-physiological and biochemical changes that adversely affect the development as well as the productivity of fruit crops. Effects of drought on fruit crops The effects of drought range from morphological to molecular levels and are evident at all phenological stages of plant growth at whatever stage the water deficit takes place. Drought restricts water supply which results in a reduction of tissue water content, stomatal conductance, metabolic processes and growth. Numerous studies have shown that plant roots can sense changes in soil water content. As soils become dry, root-sourced signals are Abstract Climate change resulted in low water availability as well as increasing demands for food in the future makes breeding for drought tolerant crops a high priority. Drought stress is one of the most ominous abiotic factor limiting the productivity and quality of fruit crops resulting in huge economic loss to the fruit growers. Plants have developed diverse strategies and mechanisms to survive drought stress. Most of these represent drought escape or avoidance strategies like early flowering or low stomatal conductance that are not applicable in breeding for crops with high yields under drought conditions. Drought tolerance is a very complex trait as it depends not only on the severity of the drought (mild or severe), but also on the developmental stage of the plant as well as the duration. From the physiological point of view, survival is the major aim in plant stress tolerance, whereas from the agricultural point of view crop yield is the trait that determines a drought tolerant crop. This review article highlights the mechanisms and strategies for drought tolerance in fruit crops. Keywords: Climate change, Abiotic stress, Drought tolerance, Strategies *Correspondence Author: Anjali Soni Email: anjali00soni@gmail.com