ORIGINAL ARTICLE Impact of water deficit stress on traits influencing the drought tolerance and yield of maize (Zea mays L.) genotypes P. Sathish 1 • M. Vanaja 1 • N. Jyothi Lakshmi 1 • B. Sarkar 1 • G. Vijay Kumar 1 • P. Vagheera 1 • C. H. Mohan 1 • M. Maheswari 1 Received: 10 February 2021 / Accepted: 10 December 2021 Ó Indian Society for Plant Physiology 2022 Abstract Water deficit stress is one of the major abiotic stresses that severely affects the plant performance and production especially when it occurs during the reproduc- tive phase. That drought research is an ongoing approach as new breeding lines development is a continuous process. Therefore, a field experiment was conducted with recently developed 12 maize (Zea mays L.) genotypes under Well Water (WW) and Water Deficit stress (WDS) conditions to quantify the impact of WD stress on phenological, physio- biochemical and yield parameters. The results showed that WD stress significantly altered the Anthesis Silking Inter- val (ASI) among the genotypes but had no effect on the genotypes DTL-4–1 and Harsha. A significant decrease in net photosynthetic rate, stomatal conductance, transpiration rate and WUE was recorded with WD stress. Accumulation of proline under WD stress was significantly higher with DTL-4–1 and Harsha with a lower malondialdehyde (MDA) content and increased activity of SOD thereby maintained better cell membrane stability (CMS). Biomass and grain yield components were also significantly impacted by the water deficit stress. Among the maize genotypes, DTL-4, DTL-4–1 and Harsha showed better Stress tolerance index (STI). Under WD stress, grain yield showed significant positive association with proline, CMS, kernel number while negative association with MDA and ASI, indicating importance of these traits in imparting WD stress tolerance in maize. Keywords Net photosynthetic rate  WUE  Proline  MDA  Grain yield  STI  WD stress Introduction Abiotic stresses particularly drought, extreme temperatures and soil salinity impact the productivity of agricultural crops. Among the abiotic stresses, drought is the major environmental stress that severely interrupt plant growth, development and yield (Shao et al., 2009) could be due to alterations in pigment content, photosynthetic activity, osmotic regulation, membrane integrity and water relations (Praba et al., 2009). Drought stress causes a wide range of physiological and biochemical changes which facilitate the plants to tolerate and adapt to such conditions with less reduction in economic yield. The adaptations include reduced photosynthesis, decreased stomatal conductance to reduce the water loss through transpiration, accumulation of osmo-protectants like proline, free amino acids (FAA) in the cell (Anjum et al., 2017). Maize (Zea mays L.) is the third most important cereal crop after wheat and rice in terms of global grain produc- tion. Globally this crop is cultivated in nearly 150 Mha with a production of 782 Mt. India has achieved 26 Mt of maize production and by 2022 it is expected that the requirement would be 45 Mt and of which 30 Mt will be used for feed and 15 Mt for food, seed and industrial use (FICCI’s ‘India Maize Summit’ 2018). Maize crop requires at least 500 to 600 mm of rainfall for good yield production and in major production zones the crop faces water deficit stress (WDS) from the tasseling to grain filling stages. The water deficit condition during reproductive growth con- siderably affects the productivity of the maize crop. The maize crop is susceptible to WDS at vegetative, pollination & P. Sathish santhurainbow@gmail.com 1 ICAR- Central Research Institute for Dryland Agriculture, Santoshnagar, Hyderabad 500 059, India 123 Plant Physiol. Rep. https://doi.org/10.1007/s40502-021-00640-x