Utilization of biotechnological approaches for germplasm conservation and sustainable use of underutilized fruit species in India

摘要

India with its rich and diverse agro-climatic conditions has great potential for cultivation of many underutilized fruit species. Many significantly important underutilized fruit species viz., bael {Aegle marmelos L.J, jamun {Syzygium cumini L.}, jack{Artocarpus heterophyllus Lam.) and ber/Indian jujube {Ziziphus mauritiana Lam.), aonla or Indian gooseberry {Emblica officinalis Gaertn.J, karonda {Carissa carandas Wight), phalsa [Grewia subinaequalis L.), wood apple or elephant apple (Feronia HmoniaL.J, tamarind [Tamarindus indica L.), etc. originated in India owing to its rich nutritional values and of late, the fruits are in great demand, fetching premium price in the market. The fruits are rich in vitamin A, C, potassium, antioxidant polyphenols, dietary fibers and are low in calories, etc., being utilized for many medicinal properties and processing purpose as well as dessert purpose. It is adapted to many diverse regions of tropical, sub-tropical, arid and semi-arid situations and as well astolerant to biotic and abiotic conditions. These features make the fruit species a potential choice for commercial exploitation even in marginal and problematic soil and agro-climatic conditions. Hence, wild fruit species must be exploited and genetic diversity should be conserved by ex situ and in situ strategies. Ex situ and in situ conservation strategies require a large area, a huge effort for maintenance and they are labour intensive, which is likely to be affected by natural calamities such as extreme adverse climatic conditions including flooding, rainfall, etc., as well as human disturbance. Therefore, biotechnological approaches serve as an alternative method for genetic conservation means and studies of genetic diversity for many important underutilized fruit species. Besides, through tissue culture techniques, using plants parts like axillary buds, shoot tips, leaf bits, petioles explants, etc., for mass multiplication of true to type planting materials can be produced under aseptic conditions. In vitro conservation of explants of important wild species of underutilized fruit species can be achieved using suitable growth hormones for long term storage of germplasms. Cryogenic storage (-196°C liquid nitrogen) of explants under controlled conditions can lead to sustain storage of germplasms for many years without losing viability and genetic stability. Hence, in vitro conditions require less space for a large number of germplasms. It is less labour intensive. This approach aides in conservation of rare and limited wild species for future utilization in crop improvement.