PLANTATIONS

Unlike other perrenials, tea is unique because only its vegetative parts - the two leaves and the bud - are commercially exploited. Tea is also maintained as a low bush ina continuous phase of vegetative growth. Both these aspects call for manipulation of plant parts for optimal productivity and growth.

The term 'flush' describes the growth by the apical bud between two successive phases of dormancy. The phase of dormancy or resting period of the shoot is banjhi phase, and the apical bud is then described as the banjhi bud. This is enclosed by two bud scales or cataphylls called the janams. The position of janam or fish leaf on the shoot is of great importance in considering the standard of plucking.

The breaking of dormancy is marked by the unfolding of the bud scales which drop immediately, leaving their scar marks on the stem. As the bud continues unfolding, normal leaves are produced which grow in size, that is, become the flush leaves with elongating internodes. After the sequence of production of normal leaves, the shoot again goes banjhi, thus completing one phase of production, followed by further ones of the same type, and the process recurs. This periodicity between banjhi and productive phase of the shoot is intrinsically regulated, independent of plucking: a typical 'growth' being a composite of two scale leaves, a fish leaf (janam) and four flush leaves.

Clearly therefore growth habit is of great significance in tea productivity; productivity is not only inexorably linked to bud and shoot growth, but higher productivity is possible to achieve only by biological manipulation of the growth processes. The process starts with the selection of seeds. The seeds can be improved by production of new seed varieties.

  Vegetative Propagation: For the improvement of quality, clonal varieties can be used which are produced by vegetative propagation. By this process, a variety can be grown vegetatively without going through the usual cycle of annual growth.

  Planting: Planting is a crucial operation as it basically determines the development and productive level of tea throughout its economic life. Wrong planting of good planting materials is doubly unproductive as investment is lost both on account of producing the plants and  in the failure to put them up for productivity. Therefore, care, planning and refinement of techniques are essential for long term benefits.

  Pruning: It basically helps  in maintaining the plant as a low bush in a phase of continuous vegetative growth. Pruning both stimulates and controls growth. It removes dead, diseased and overage wood, and thus helps rejuvenate bushes that have crossed the period of maximum productivity.

  Fertilizer: The nutrients that are removed from the plant as yield and from the soil by the plant for its growth, should be replenished.Ideally, nutrient requirements should be related to local soil conditions in addition to yield and they must be monitored continuously to ensure an optimum balance of nutrients.

  Weed control: Weeds affect tea by competing with it for moisture, nutrients and sunlight. The ultimate effect is a considerable reduction in yield. Thus, the timing of weed emergence relative to the growth stages of tea is an important parameter in weed management. Apart from directly causing crop losses, weeds in tea areas also acts as      secondary hosts for some important pests of tea.

 Pest Management: The simultaneous presence of different species of mites and insects, each with their characteristic mode of feeding, diverse habitat and seasonal cycles, call for optimal management of the pests  which should be both ecologically and economically sound.

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