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The indigenous Assam tea plant was discovered by Robert Bruce in 1823. However, commercial tea cultivation was initiated in India during 1834, using a China tea plant. The better cup quality produced by the Assam tea plant popularized it as an important planting material in the tea industries of the country. Seeds were the only source of propagation until the discovery of the vegetative method. As a result, seed jat populations of unknown parents created a wide range of genetic variation and resulting inconsistency in their performance. Considering the need for improved planting materials for the tea industry, Tocklai Experimental Station (TES) Tea Research Association, initiated a tea breeding programme in 1930, under which germplasms were collected based on trait specific phenotypic characteristics. Promising plants selected from heterogeneous jat populations as well as from wild tea patches were characterized and preserved in the gene bank of TES, along with some of the non-tea Camellia species for utilization in the breeding programmes. The Tea Research Foundation, United Planters’ Association of Southern India (UPASI), initiated a similar program in 1963 and collected germplasms were preserved in their gene bank. The technique of vegetative propagation, standardized in 1955, provided scope for developing improved clonal cultivars as well as biclonal seed cultivars through hybridization. From the selected plants from old seed jats and progenies of biclonal hybrids, 153 locally adapted and 31 universal clones were developed for the tea industry. Under polyploid breeding triploids, tetraploids and aneuploids were produced through hybridization, out of which high yielding quality triploid plants were selected, cloned and made available for plantation. Water logging tolerant genotypes have been selected and used as parents in the breeding programme for the development of tolerant cultivars and progenies. EST’s have been developed from Camellia species and a cDNA library was constructed. Marker development for draught resistance and blister blight disease is under progress using cDNA-AFLP and EST-SSR techniques. Transgenic technology has been developed and vector construction is completed to confer resistance against blister blight. The micropropagation technique has also been standardized for quick multiplication of these biotechnologically modified plantlets. Details of tea breeding in India are discussed in this chapter. |
