Unlocking rice drought tolerance through affordable phenotyping methods

Meeting the food needs of a growing population amid climate change proves to be an arduous challenge for the agriculture sector in the upcoming decades. Rice is one of the major staple food crops of the world and global rice production has been drastically impacted by frequent and intense drought events driven by climate change. A rapid, accurate, and cost-effective phenotypic evaluation of large breeding lines under adverse conditions is an important component in accelerating the development of improved cultivars. Precise phenotypic evaluation of rice for drought tolerance is generally done using manual methods, which is inefficient, invasive, and error-prone. Plant phenotyping approaches have advanced significantly over the past years and a variety of flexible, affordable, and non-invasive methods for acquiring, storing, and analysing data are now available. These technologies enable accurate quantitative assessments of modulations in plant structure and function under the impact of drought stress and convert them to interpretable datasets. Such reliable phenotypic data can be a helping hand in plant selection and can fast-track the crop improvement programmes for development of drought tolerant varieties in rice. The current review emphasizes the different rapid and low-cost plant phenotyping approaches, which can precisely document the various above ground and below ground parameters in rice pertaining to drought tolerance both under controlled and field conditions.