Bael tree (Aegle marmelos (L.) Corrêa): importance, biology, propagation, and future perspectives

Abstract

Major advances have been made in our understanding of the biology and biotechnology of the bael tree (Aegle marmelos), which is used for marmalade and has other applications. Aegle marmelos (L.) Correa (Rutaceae), popularly known as bael fruit or stone apple tree, and the basis of marmalade, is a deciduous tree with extensive medicinal, pharmacological, ethnomedicinal and conventional properties and uses. Aegle marmelos shows wide ecophysiological plasticity, including resistance to high temperature stress, while salt-resistant cultivars also exist. Its ability to grow in a wide range of soil pH makes A. marmelos an economically viable fruit tree for otherwise difficult-to-culture environments, and its adaptability to various ecological niche makes it an excellent candidate for agro-forestry and the reclamation of waste lands, but the choice of breeding parents for cross-pollinated experiments can affect fruit set. The micropropagation of A. marmelos offers an opportunity to conserve, through large-scale propagation, elite genotypes, although greater exploration of genotype collections is required to identify superior germplasm. This review explores the importance, adaptive physiology, disease and pest management, genetic diversity, conventional propagation and the use of tissue culture to propagate A. marmelos, either through direct or indirect organogenesis, or through somatic embryogenesis, genomics and future perspectives.