PHYSIOLOGICAL
AND BIOCHEMICAL BASIS OF CLONAL SECTION in
tea Conventionally, promising traits were selected
on the basis of morphological characters and
yield potential of a particular accession which
needs man power and has prolonged gestation
period. Recently, physiological and biochemical
markers have been employed in clonal identification.
Based on the data generated, a multiple regression
model was formulated and validated to predict
the productivity of the seedlings planted in
tea gardens. The origin and parentage of these
seedling populations was not known. On the basic
of green leaf constituents, a regression model
was developed to predict the quality constituent
of black tea. Similarly, data based on stress
related parameters was prepared and correlated
individually with yield for screening the productivity
under soil moisture stress. Out of 254 mother
bushes selected from the estates, 83 were identified
as productive plants with good quality and high
yielding capacity besides a few accessions performed
well during soil moisture stress. Field evaluation
of the selectively planted germplasm is in progress.
CATECHIN BIOSYNTHESIS
pathway in tea Among the tea polyphenols, catechins
gained importance in recent years because of
their antioxidant potential. In view of importance
of catechins, biochemical charecterisation and
influence of environmental, edaphic and agronomic
practices in catechin biosynthesis were envisaged.
Tea clones were characterized on the basis of
catechins and their fractions. According to
the principle component analysis, UPASI clones
were segregated into five distinct groups. Segregation
of these clones was on the basis of ratio between
dihydroxylated to trihydroxylated catechins.
Substrate specific catechin biosynthesis was
confirmed with radio labelled isotopes. Abiotic
factors and agronomic practices played an important
role in catechin biosynthesis. To generate data
on the factors influencing catechin biosynthesis
in tea a number of experiments were conducted
and the generated results were documented.
GERMPLASM CHARACTERIZATION AND FIELD EVALUATION
OF IN VITRO DERIVED TEA PLANTS Under
the auspicious of DBT funded project, “Improvement
of tea through biotechnological tools”
complete characterization of existing clones
using physiological, biochemical and molecular
tools and in vitro propagation and field establishment
of superior clones have been studied. So far,
one hundred and fifty tea accessions including
UPASI released clones and selections from the
germplasm collections were used for characterization.
Generated data were documented as per the requirement
of National Bureau of Plant Genetics Resources
(NBPGR), New Delhi. Molecular characterization
has been initiated using RAPD and ISSR for the
development of molecular markers for desired
traits and to assess the genetic diversity among
the south Indian germplasm. In vitro derived
tea plants were maintained under green house
conditions will be planted during the current
planting season.
Clonal
propagation of plants in laboratory
( Growth stages )
ADVANTAGES
Propagation of elite cultivars
( Irrespective of origin & age )
Mass multiplication Storage
Germplasm collection