We are grateful to Mangalore University for permission to carry out this study at the Department of Biosciences. Authors acknowledge helpful suggestions by Dr. K. Nandkumar, Department of Botany, Goa University, Goa, India and
Dr. Janardhana, G.R., Department of Botany, University of Mysore, Mysore, Karnataka, India. We are indebted to the editor and two anonymous reviewers for constructive suggestions to substantially improve the presentation of this study