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Madhya Pradesh and so far 114 000 ha teak plant-
ation has been raised (Gangopadhyay, 2005).
In 1891, T.F. Bourdillon introduced traditional stump
planting technique for teak planting. After hundred
years Maharashtra Forest Development Corporation,
in 1991 introduced a new nursery technique for raising
nursery stock of teak in root trainers (Khedkar and
Subramanian, 1995). The root trainer technology for
teak was developed in 1988 by Kerala Forest Depart-
ment initiated by Prabhu (1998). Since then, millions
of teak seedlings have been raised in root trainers.
Teak was raised on plantation scale in Kerala by
British rulers and subsequently after independence
was taken over by Kerala Forest Department (KFD).
These plantations are established based on various age
groups and site quality classes. Seed orchards form an
important connection between ongoing tree improve-
ment programme and profitable planting. Seed orchards
are indented to supply superior seeds in ample quantity
(Zobel, 1984).
Vegetative propagation can play a key role in tree
improvement programme as a means of large scale
multiplication of planting material for plantation
forestry and agro- forestry in the tropics. It is the
method of rising planting stock not involving seed;
but, includes cuttings, layering, budding, grafting and
recently micropropagation. Propagating plants vegeta-
tively results in clones, with each clone retaining the
genetic characteristics of the tree at the point from
which the buds or cuttings were obtained (Evans and
Turnbull, 2004). Vegetative propagation by grafting
has been suggested as a possible method for raising
plants for the establishment of teak seed orchards.
This technique has been standardized in teak by Ked-
harnath and Venkatesh (1963). Clonal seed orchards
(CSO) are established through planting vegetative
propagated plants of phenotypically superior trees and
managing them as isolated plantations to get genet-
ically improved seed lot, through intermating of these
superior types.
Teak genetic improvement was started in India in the
year 1954. Teak improvement was limited to establishing
seed production areas (SPAs) and clonal seed orchards
(CSO). CSOs are established with grafted plants of
superior phenotypes (plus trees) selected from natural
forests and plantations. These "plus trees" were chosen at
a very high intensity (often one in several hectares of
forests) with rigorous selection criteria (Emmanuel
and Bagchi, 1988; Kumar et al., 1998). CSOs are the
only source of ex-situ conservation for teak in India.
Although, CSOs are good collection for static conser-
vation, they represent only a fraction of the total
genetic variation present within the species. One
objective of tree improvement program is mass production
of genetically superior seed. Such seeds are usually
collected from CSOs or seedling seed orchards (SSOs).
The seed orchards are always involved in major
breeding programs all over the world. Estimation of
genetic gain and gene diversity aspect of seed orchard
crops is crucial for management and conservation of
the clones in the clonal seed orchard. Clonal breeding
value, fertility variation, pollen contamination and
seed production are the major factors for consideration
when genetic gain and diversity are estimated.
More than 1 000 ha of CSOs have been established in
India with 450 ha in Maharashtra, 240 ha in Madhya
Pradesh, 120 ha in Karnataka, 92 ha in Andhra Pradesh,
35 ha in Kerala, 30 ha in Orissa and Tamil Nadu, and
25 ha in Arunachal Pradesh (Katwal, 2005). CSOs are
the main focus of genetic improvement of teak in
India; but the output from these orchards has been far
from satisfactory. Poor flowering, asynchrony in
flowering phenology, low fruit and seed set were the
major problems faced (Nagarajan et al., 1996; Indira
and Basha, 1999; Vasudeva et al., 2001; Mathew and
Vasudeva, 2003; Gunaga and Vasudeva, 2005). Teak is
the most widely planted and researched tropical
hardwood species that is propagated and domesticated
through plantations for one and a half centuries.
Significant research and development had taken place
in the standardization of techniques/methods applied
in raising plantations, harvesting and post-harvesting
utilization and tree improvement activities. Despite
these efforts, teak resources of the world need instant
attention for their sustainable management. Raising
teak monoculture on the basis of ecological and
economic aspects has to be considered for long term
execution of supply of timber. At the same time