MORPHO-PHYSIOLOGICAL RESPONSES OF TOSSA JUTE (Corchorus olitorius L.) UNDER DIFFERENT ABIOTIC STRESSES AT VEGETATIVE STAGE

Abstract

Abiotic stress has become an alarming issue for plants survivable due to the constant changes in the environment. Stresses such as drought, salt, waterlogging and heavy metals largely influences plant growth and development that finally reduces crop productivity. Focusing this issue, two individual experiment, germination trial (Experiment-I) and pot experiment (Experiment-II) were carried out at Sher-e-Bangla Agricultural University, during the kharif-1 season of 2019 to investigate the responses of tossa jute (Corchorus olitorius) cv. O-9897 under different abiotic stresses. Experiment-I and Experiment-II were designed in completely randomized design (CRD) and randomized complete block design (RCBD), respectively. In Experiment-I seeds were exposed in two doses of salt (75 and 100 mM NaCl) and Cd stress (0.5 and 1 mM CdCl 2 ). Germination parameters were affected by salt stress where seedling parameters were highly damaged by Cd stress. At 15th day after sowing (DAS) plants were exposed to salt, cadmium (Cd), waterlogging and water deficit condition for various duration in Experiment-II. Two doses of NaCl (200 and 400 mM) were applied to impose salt stress, while two doses of CdCl 2 (2 and 4 mM) were applied for Cd stress. Among two waterlogging treatments, 5 days of waterlogged condition was imposed at 15 and 30 DAS in first one and in second one 20 days of waterlogged condition was imposed. For water deficit, water was withheld from soil for the duration of 10 and 15 days. Morphological parameters like plant height, relative water content, above ground fresh and dry weight, SPAD value, leaf area and stem diameter were decreased upon exposure to salt, water deficit, waterlogging and Cd. These treatments were also resulted in oxidative stress which was evident by the increased levels of lipid peroxidation (MDA), H 2 O 2 and electrolyte leakage and decrease in catalase enzyme activity. Results also revealed that waterlogging and drought stress drastically affected plants morpho-physiology, whereas C. olitorius could tolerate moderate level of salt (i.e. 200 mM NaCl) and Cd (i.e. 2 mM CdCl 2 ). Considering this fact, it may be concluded that tossa jute become susceptible towards either duration of waterlogging and drought stress, salt stress more than 200 mM NaCl and Cd stress, more than 2 mM CdCl 2 .