About 90 percent of the poplar plantations in India are
based on clones G-48, D-121, S7C15 and G-3. The yield of clone G-3, which once
used to be the most popular clone, is declining due to attack by leaf blight
disease. This clone is giving way to other clones, e.g., S7C8, Uday, L-34/82
etc. Individual plantations are, however, monoclonal (Kumar et al, 1998).
To increase the productivity of poplar, FRI Dehradun started
a National Poplar Improvement Programme in 1997. Salient achievements of this
initiative are:
(i) Clones of poplar introduced in India since late-1950
were ranked on the basis of volume growth. Clones S7C8, 82-35-4 and 113324 were
found to give higher yield than G-48, presently one of the most popular clones
in agroforestry plantations. Based on these rankings, a vegetative
multiplication garden was established at FRI, Dehradun to supply cuttings of
superior clones to growers.
(ii) Multilocation field trials of best 60 clones of
previous introduction have been established at about 30 sites throughout the
traditional as well as potential zones of poplar cultivation covering Jammu and
Kashmir, Himachal Pradesh, Punjab, Haryana, Uttar Pradesh, Bihar, West Bengal,
Orissa, Chhattisgarh, Maharashtra, Gujarat, etc. Fifteen Research Institutions
comprising Universities, State Forest Departments are collaborating with FRI,
Dehradun in this programme.
(iii) Intraspecific hybridisation amongst best 40 clones has
been carried out. 289 clones from control-pollination and 111 clones from
open-pollination have been selected for field trials.
(iv) Seed from 104 candidate plus trees growing in 44
natural stands in the USA has been brought to FRI Dehradun. 100 clones have
been selected out of the new germplasm for further trials (Singh et al,2003).
(v) A new approach of multi-step selection and concurrent
multiplication has been developed at FRI Dehradun which enables multiplication
of germplasm of superior clones at 2 years of age while clonal trial is stilI
underway. This reduces the time period in clonal testing and multiplication
process by 4
years (Kumar and Singh, 2000).
(vi) Hybrid seedlings of P. deltoides 'G-48' x P. euphratica
have been produced to combine the rapid growth of P. deltoides and stress
tolerance of P. euphratica (Singh et al, 2003)
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