Micropropagation of Philodendron selloum: Influence of copper sulfate on endophytic bacterial contamination, antioxidant enzyme activity, electrolyte leakage, and plant survival
Mayada Seliem, Mohammed E. El-Mahrouk, Antar El-Banna, Yaser Hafez, Yaser Hassan Dewir
Abstract
Endophytic microorganisms is a major constrain to the establishment and growth of tissue culture plants. We report the use of copper sulfate (CuSO 4 .5H 2 O) to eliminate the endophytic bacteria in Philodendron selloum in vitro cultures. Contaminated shoots were cultured onto Murashige and Skoog (MS) medium containing 5 mg/L BA and supplemented with different concentrations of copper sulfate at 0, 35, 70 and 140 mg/L for 6 weeks. Copper sulfate at 70 mg/L completely eliminated the endogenous bacteria without decline in plant growth. However, 35 mg/L copper sulfate was optimal for maximum shoot multiplication (25), survival percentage (100%) and growth of plants. Antioxidant enzymes activity of catalase, peroxidases, and polyphenol oxidase were increased because of copper sulfate treatments. Conversely, electrolyte leakage was decreased at low copper sulfate (≤70 mg/L). Randomly amplified polymorphic DNA (RAPD) analysis revealed that plantlets exposed to different levels of copper sulfate were not genetically different from control plants.