Vol.:(0123456789) 1 3 Plant Biotechnology Reports https://doi.org/10.1007/s11816-020-00598-6 REVIEW Genetic engineering approaches to understanding drought tolerance in plants Zabta Khan Shinwari 1  · Sohail Ahmad Jan 2  · Kazuo Nakashima 3  · Kazuko Yamaguchi‑Shinozaki 4 Received: 20 November 2019 / Accepted: 21 January 2020 © Korean Society for Plant Biotechnology 2020 Abstract Abiotic stresses such as drought, salinity, frost, etc., afect plant yield manyfold. These stresses can decrease the plant yield of important major crops up to 50%. The abiotic stress-related genes or other transcription factors (TFs) have multiple functions, as it increases proline content, leads closing of stomata to decrease the transpiration rate, enhances the production of some important stress-related protective enzymes, etc. and hence increases abiotic stress tolerance. Many TFs and other stress- related genes have been identifed and characterized and transformed to many important cultivated plants against drought and others abiotic stresses. The transformed plants show better morpho-biochemical and physiological performances than non-transgenic plants. Many genetically engineered plants have been developed against drought stress including wheat, rice, tomato, soybean, cotton and many more. The efciently engineered clustered regulatory interspaced short palindromic repeats (CRISPR)/CRISPR-associated nuclease 9 (Cas9) system is now becoming a preferred choice of researchers to edit plant genomes for introgression natural resistance against a range of abiotic stresses. It leads genome editing by precise manure with minimal or no efect on growth and development of plants. Very limited reports are available to develop drought-tolerant plants using CRISPR/Cas9 system. Here we discuss transgenic plant technology and new [CRISPR Cas9 and Virus-Induced Gene Silencing (VIGS)] techniques to confer drought tolerance in important plant species. Keywords Abiotic stress · CRISPR/Cas9 · Drought stress · Transcription factor · Transgenic plants · VIGS Introduction Global food security is one of the key issues due to change of world climate condition and by the increase of population. Drought, salinity, heat, etc., stresses signifcantly afect plant yield and productivity (Nouri et al. 2015; Singh et al. 2018). Drought and salinity afect about one-third of our cultivated land and it cause loss of approximately 1,500,000 ha crop land/year (Peng et al. 2011). In recent years, drought stress signifcantly decreased the plant yield manyfold by disturbing its morpho-biochemical processes (Azevedo et al. 2011). Even lower heat and drought stress afect plant yield. These stresses reduced crop yield by up to 50%. The plants in reproductive stages are more sensitive to these stresses and thus afect yield of many important plant species (Lamaou et al. 2018). Plants are more susceptible to these extreme environmental stresses as compared to any other living organisms. Plants respond poorly to high environmental stresses, as it afects both biochemical and physiological processes. So, the development of new engineered plants is important to fght against these stresses (Ramonell and Somerville et al. 2002). Decreasing the water amount up to 40% declines the yield of maize and wheat by as much as 40% and 21% (Daryanto et al. 2016). The important cultivated cowpea yield is afected up to 68% by drought stress (Farooq et al. 2017). About 40% of soybean yield loss occurs due to drought stress (Specht et al. 1999). It also reduces cell division, spreading of leaf surface, retards stem growth and root propagation (Anjum et al. 2015). Long-term Online ISSN 1863-5474 Print ISSN 1863-5466 * Zabta Khan Shinwari Shinwari2008@gmail.com * Sohail Ahmad Jan sjan.parc@gmail.com 1 Pakistan Academy of Sciences, Islamabad, Pakistan 2 Department of Biotechnology, Hazara University Mansehra, Mansehra, Khyber Pakhtunkhwa, Pakistan 3 Japan International Research Center for Agricultural Sciences, Tsukuba, Ibaraki, Japan 4 The University of Tokyo, Tokyo, Japan