Plant Tissue Culture : A Promising Tool Of Quality Material Production With Special Reference To Micropropagation Of Banana

In the very fast developing scenario of biological science, the plant tissue culture has taken lead as the most promising areas of application of biotechnological tools for today and tomorrow agriculture. The areas ranges from micropropagation of horticultural crops, ornamental and forest trees etc., production of pharmaceutically important compounds, and plant breeding for improved nutritional value of staple crop plants, including trees for cryopreservation of valuable germplasm. The rapid production of high quality, disease free and uniform planting stock is only possible through micropropagation. Plant production can be carried out throughout the year irrespective of season and weather. However micropropagation technology is expensive as compared to conventional methods of propagation by means of seed, cuttings and grafting etc. Therefore, it is essential to adopt measures to reduce cost of production. Low cost production of plants requires cost effective practices and optimal use of equipment to reduce the unit cost of plant production. It can be achieved by improving the process efficiency and better utilization of resources. Use of ‘Bioreactor’ in plant propagation can increase the speed of multiplication and growth of cultures and reduce space, energy and labor requirements. The cost of production may also be reduced by selecting several plants that provide the option for around the year production and allow cost flow and optimal use of equipment and resources. Quality control is also very essential to assure high quality plant production and to obtain confidence of the consumers. The selection of explant source, diseases free material, authenticity of variety and elimination of somaclonal variants are some of the most critical parameters for ensuring the quality of the planting materials. The in vitro culture has a unique role in sustainable and competitive agriculture, forestry and pharmaceutical industry and has been successfully applied in plant breeding for rapid introduction of improved plants. Plant tissue culture has become an integral part of plant breeding. At present plant cell culture has made great advances. Possibly the most significant role that plant cell culture has to play in the future will be in its association with transgenic plants. The ability to accelerate the conventional multiplication rate can be of great benefit to many crops/countries where a disease or some climatic disaster wipes out crops. The loss of genetic resources is a common story when germplasm is held in field gene banks. In vitro storage using plant tissue culture tools and cryopreservation are being proposed as solutions to the problems inherent in field gene banks. By these means the future generations will be able to have access to genetic resources for simple conventional breeding programmes, or for the more complex genetic transformation work. As such, plant tissue culture has a great role to play in agricultural development and productivity. In this review, important steps of plant tissue culture, its critical precautionary points and commercial applications have been discussed. As Banana is an important food crop and the second most important fruit crop after mango, a special account has been taken into consideration to also put on record the steps involved in successful micropropagation of it. Despite the significant commercial value of the banana crop, the main production constraint is the availability of reliable and safe planting material. The planting materials obtained through conventional methods (suckers) do not meet the increasing demand for planting and they are of poor quality. Tissue culture is the approach which can solve these problems. Micropropagation of the planting material is also facing the different challenges which need to be addressed in order to improve its quality production. Some of the problems which impair the success of the crop include oxidative browning of the wounded tissues and low number of shoots produce per explant. This review includes the micropropagation studies of commercially important cultivars of banana in the country, highlights the challenges encountered in its tissue culture and explores the possibilities of optimization of the in vitro propagation techniques by using explants from shoot tip.