Planting materials

Seed

Commercial planting of tea in Northeast India began in the fourth decade of the 19th century with seeds of small dark leaf race of tea imported from China. Meanwhile the merit of the large, light leaf Assam race of tea was demonstrated by the auction of a small consignment of this tea in the London tea market on 10th January 1839. This was a momentous occasion because besides establishing the worth of Assam race of tea, it determined the further course of tea cultivation throughout the world. Much more tea is commercially made from the Assam race of tea than from the China race. The China race is grown in areas where the temperature drops very low during a part of the year.

Discovery of the value of the Assam race of tea induced the early planters in Assam to explore the tea tracts abandoned by the migratory hill tribes inhabitating the Borail mountain range along the South and Southeast border of Assam. The limited quantity of collected seeds of the Assam race planted in nurseries provided some material for commercial planting and some seedlings were used for planting seed orchards. To meet the requirement of seed for the rapidly expanding tea areas, a fairly large number of seed orchards were established primarily in Assam during the second half of the 19th century.

Tea seed production became a lucrative trade since these seeds are in large demand not only in North East India but also in South India, Indonesia, Africa and Sri Lanka to which large consignments of seeds are exported.

It may be mentioned in this connection that the three races of tea hybridise freely which must have happened to some extent under natural conditions in Southeast Asia, which is the home of tea, and other Camellias. Hence the races of tea are not genetically pure but are assigned to the three types on subjective judgement based mainly on shape, size and colour of leaf and nature of bush frame.

Tea seed bari

Clone

Until the middle of the last century tea was grown essentially from seed throughout the world. Development of a simple, cheap and rapid method of vegetative propagation of the tea plant in the third and fourth decades of the last century at Tocklai made it possible to release elite plants and multiply them vegetatively as clones for economical planting. Tocklai released the first tea clone in the world in 1949.

More clones had since been released with the progress of time, the total number at the end of 2002 being 30 excluding 151 clones selected in commercial tea estates.Two new TV clones are in the pipeline, which are under multilocational trials. Following are the clones so far released by Tocklai for commercial cultivation:

Standard clones: TV2, TV3, TV4, TV5, TV6, TV7, TV10, TV11, TV12, TV13, TV14, TV16, TV17, TV20, TV24, TV27, AND TV28 have above average yield & quality with high yield potential of about 3000-3500 kg made tea/ha.

Yield clones: TV8, TV9, TV15, TV18, TV19, TV22, TV23, TV25, TV26, TV29 AND TV30 have average quality but high yield with yield potential of 4000 kg made tea/ha and above.

Quality clones: TV1 and TV21 have high quality but average yield with yield potential of about 2500-2800 kg made tea/ha.

Characteristics of TV clones
Characteristics of TRA-Garden series clones

Seed and clone

Being the progeny of a hybrid parents, no two bushes in a population of tea raised from seed are alike. Hence, seed populations can be fitted into a wide range of environmental and cultural conditions without much change in their overall performance. On the otherhand all bushes of a clone widely separated in space and time behave in most ways as a single bush. Being genetically different all bushes of a seed population are unlikely to suffer equally from the attack of a pest or a disease while all bushes of a clone will be equally susceptible. Hence absolute dependence on clones for commercial cultivation of a long duration crop like tea is a risky proposition. Realizing this danger Tocklai started breeding clonal seed stocks (varieties) along with the selection of clones.

Tocklai has already produced and released 14 biclonal seed varieties (i.e., each variety involves only two parental clones). Then the clonal seed stocks are of equal or nearly equal merit as the selected clones. The seed stocks are produced to serve the needs of the different soil climatic regions of North East India. The tea industry is now using these seed stocks for replacement or extension of tea areas along with clones.

The biclonal seed stocks released by Tocklai till the end of 2002 are TS 378, TS 379, TS 397, TS 449, TS 450, TS 462, TS 463, TS 464, TS 491, TS 506,TS 520, TS 557, TS 569 and TS 589.

Characteristics of biclonal seed stocks

Guidelines for use of seed and clone

  1. No single clone should occupy more than 10% of the total area of a tea estate.
  2. A minimum of 5 clones should be grown in an estate.
  3. Ideal clone to seed ratio is 1:1.