American Journal of Plant Sciences, 2020, 11, 2080-2102 https://www.scirp.org/journal/ajps ISSN Online: 2158-2750 ISSN Print: 2158-2742 DOI: 10.4236/ajps.2020.1112147 Dec. 24, 2020 2080 American Journal of Plant Sciences Screening of Rice Accessions for Tolerance to Drought and Salt Stress Using Morphological and Physiological Parameters Chukwudi Umego 1 , Valentine Otang Ntui 1,2 , Effiom Eyo Ita 1 , Charles Opara 1 , Edak Aniedi Uyoh 1* 1 Department of Genetics and Biotechnology, University of Calabar, Calabar, Nigeria 2 International Institute for Tropical Agriculture, Nairobi, Kenya Abstract Drought and salinity are the most widespread soil problems, posing a big threat to food security in rice growing regions. The present study evaluated the performance of eleven rice genotypes using morphological and physio- logical parameters, under induced drought and salinity conditions. The seedlings were raised in 5 kg of homogenous soil in plastic bags in the green- house. For the drought experiment, each bag was watered with 200 ml of wa- ter twice daily until plants reached the five-leaf stage when watering was sus- pended for 2 weeks for the drought stressed plants but not suspended for the control plants. The experiment was a 2 × 11 factorial and the set up was ar- ranged using the completely randomized design with three replications. Data were taken on Plant height, Number of tillers, leaf length, Number of green leaves, Number of dead leaves, Leaf rolling score (LRS) and Rate of water loss. The salinity experiment was set up in a similar manner except that the plants were irrigated twice a day for 2 weeks with 200 ml of treatment solution con- taining either 0 mM NaCl or 75 mM and data were collected on plant height, number of tillers, shoot fresh weight, shoot dry weight, Na + and K + concen- trations, relative water content and chlorophyll content. Data from both ex- periments were subjected to Analysis of variance test using the GenStat soft- ware 10 th edition and the means separated using least significant difference test. Individual stress response index (ISRI) was calculated for each parameter and the means used in grouping the varieties. Of the genotypes evaluated, four (FARO 44, NERICA 2, NERICA 8 and NERICA 5) were identified as to- lerant, two (NERICA 4 and FARO 57) as moderately tolerant, while the rest were found to be sensitive to drought. Equally, two varieties (FARO 44 and RAM 137) stood out in the salinity screening as tolerant varieties, five were moderately tolerant while four (FARO 64, FARO 52, NERICA 2 and FARO How to cite this paper: Umego, C., Ntui, V.O., Ita, E.E., Opara, C. and Uyoh, E.A. (2020) Screening of Rice Accessions for Tolerance to Drought and Salt Stress Using Morphological and Physiological Parame- ters. American Journal of Plant Sciences, 11, 2080-2102. https://doi.org/10.4236/ajps.2020.1112147 Received: November 7, 2020 Accepted: December 21, 2020 Published: December 24, 2020 Copyright © 2020 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access