In Vitro Clonal Propagation of Some Important Woody Bamboos and Ascertaining Their Clonal Fidelity

Abstract

Bamboos, one of the natural resources of the tropics are fascinating plants because of an array of phenotypic variability, adaptability to different adaphic zones and amenability to be used variously. These are among the most popular groups of plants with more than 1500 documented applications. For billions of people in Asia, South-America and also Africa, bamboos are an integral part of their daily life requirements. In the last two decades, population growth and new bamboo processing opportunities have led to the over exploitation of bamboo resources, despite stricter regulations and even ban on harvesting in some countries notwithstanding. Due to the diminishing wood supply, bamboos are now in high demand as raw material sources for furniture, handicraft and many other industrial products. Inefficient and labour intensive conventional methods for propagating bamboos, gregarious flowering habit, poor seed set and low viability, and human population pressure disrupting the natural cycle of reforestation present an urgent need for developing methods for large scale propagation of bamboos. In this regard, efficient in vitro propagation methods using explants taken from established and selected mature plants would offer a feasible alternative for large scale multiplication of elite bamboos Keeping in view the importance of bamboos, attempts were made to establish efficient and reproducible protocols for large scale propagation of some economically important bamboo species viz. Bambusa tulda, Dendrocalamus asper, Guadua angustifolia, Phyllostachys pubescens under in vitro conditions using nodal segments. Nodal explants taken from elite mother plant were innoculated onto MS medium supplemented with different concentrations and combinations of cytokinins and auxins for inducing mutiple shoot proliferation and rooting respectively. Thereafter, the well rooted plants were acclimatized and established in the fields where they exhibited normal growth. To confirm the clonal fidelity, DNA samples from in vitro raised plants at various stages of subculture, hardened plants and mother plants were subjected to RAPD and ISSR analysis. The monomorphic banding patterns thus obtained confirmed their true to type nature. Thus, our study provides efficient methods for production of quality planting material for large scale establishment of Bamboo cover and maintain their elite genotype during their rapid multiplication cycle.