98 Original Research Article Plant Cell Biotechnology and Molecular Biology 21(47&48):98-109; 2020 ISSN: 0972-2025 MORPHO-PHYSIOLOGICAL CHARACTERIZATION OF Lagenaria siceraria L. CULTIVARS UNDER NaCl STRESS MUJAHID ALI * , ABDUL KHALIQ, CHAUDHARY MUHAMMAD AYYUB, SHAHID IQBAL, MUHAMMAD IRFAN ASHRAF, MUHAMMAD AZAM, HAFIZ MUHAMMAD TAYYAB KHAN, MUHAMMAD ALI AND KARIM YAR ABBASI Institute of Horticultural Sciences, University of Agriculture, Faisalabad-38000, Pakistan [Mujahid Ali, AK, CMA, MIA, Muhammad Azam, KYA]. Department of Horticulture, College of Agriculture, University of Sargodha, Sargodha, 40100, Pakistan [Mujahid Ali, SI, HMAK]. Department of Horticulture, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan-60800, Pakistan [Muhammad Ali]. [ * For Correspondence: E-mail: mujahidali2263@gmail.com] Article Information Editor(s): (1) Dr. Bishun Deo Prasad, Bihar Agricultural University, India. Reviewers: (1) Dhriti Kapoor, Lovely Professional University, India. (2) Amel Ghanim Muhmood AL-Kazzaz, University of Baghdad, Iraq. Received: 10 August 2020 Accepted: 15 October 2020 Published: 30 October 2020 _______________________________________________________________________________________________ ABSTRACT Salinity is a major challenge for food security globally. The study was conducted in order to identify morphological and physiological attributes which can be used for characterization of salinity tolerance in bottle gourd (Lagenaria siceraria L.). Three genotypes (Round (Local), Latto (Local) and Louki) were sown in plastic pots, using fine sand as growth medium. After one month, saline water treatments (25, 50, 75 and 100 mM NaCl) were applied except control seedlings and Hoagland solution was used as nutrient solution. Data were collected and analyzed statistically using standard statistical procedures. The results showed that salinity has adverse effect with mostly morphological characters (number of leaves, root length, shoot length, root fresh mass, root dry mass, shoot fresh mass and shoot dry mass). Similarly, physiological characters as chlorophyll contents, photosynthetic rate, transpiration rate and stomatal conductance were also affected. Study revealed that Latto (local) cultivar showed significantly better tolerance to salinity as compared to others with maximum chlorophyll content (17.36 SPAD) under salinity conditions, followed by Louki (14.19 SPAD), while the Round (Local) variety revealed minimum value for chlorophyll (11.95) under salinity conditions. Keywords: Bottle gourd; salt stress; sodicity; physiology; Na toxicity.