Technologies Developed-Department of Forest Biology and Tree Improvement

Realizing the pivotal role the forests play in the economic prosperity and ecological stability of a country, Tamil Nadu Agricultural University, Coimbatore has started a full – fledged department of Forestry in 1973 as a forerunner to a college of forestry. To sub-serve the needs of forest research, Forest Research Station encompassing an area of 200 ha was started in 1976 as an adjunct to the Department of Forestry in the sylvan surroundings of a reserve forest at Mettupalayam. The station has since been elevated to the status of Forest College and Research Institute in 1990 with the triple mandate of teaching, research and extension activities with the following organizational structure to satisfy the problems encountered by the State Forest Departments, Tree Growing Farmers and Wood based industries, the need for enlarging the education and research. In order to diversify and specialize in the various disciplines of forestry, in 1998, Tree Breeding Department was started with special emphasis on inventorying, screening and improvement of short rotation species amenable for various forest based industries besides evolving suitable technologies for its mass multiplication.

It is introduced from Australia and the wood is an excellent fuel that can readily be converted to charcoal as well as widely utilized in pyrolysis based power generation. The hard multi stem is having high density coupled with good calorific value of 4670 k.cal / kg. Early rapid growth makes A. holosericea a highly productive fuelwood source. Trees 4 years old can yield up to 13 tonns / ha.

Simarouba glauca is commonly called as ‘The King of Oilseed Trees’ .The kernels, which form 92 per cent of the seeds, yield on decortication 55 to 65 per cent of oil. The oil of Simarouba glauca is suitable for human consumption without hydrogenation or blending with other fats. The wood is white and soft and can be used for making cheap light furniture, boxes, match sticks, yokes for oxen and also as good fuel. Eightyear-old tree yields 42.9% of screened pulp. The species is highly drought tolerant, adapts to all kinds of soil except coastal sandy soil, can check erosion and has enormous potential for wasteland reclamation. It is a promising species for wasteland afforestation and establishing green belts.

TNAU Casuarina MTP 1 is an introduced multipurpose species suitable to wide range of edapho-climatic conditions preferably sandy loam soil. This variety is the selection from the existing plantation which is a male parent and will not produce seed and hence multiplication is through Clonal technology. The yield recorded ranged from 100 tonnes to 125 tonnes per ha in 5 years which generated significant increased income to the growers. The clones have cellulose content of more than 46 percent coupled with satisfactory strength properties which made this species as a potential pulpwood

TNAU Casuarina MTP 2 is a natural sterile hybrid between Casuarina equisetifolia and Casuarina junghuhniana. Predominantly this variety is being propagated through vegetative propagation. This variety has the capacity to yield 125 – 150 tonnes per ha in 3 years as against 80 tonnes per ha in 4-5 years of the traditional variety. The yield recorded ranged from 137 tonnes to 195 tonnes per ha in 3 years which generated significant increased income to the growers. A financial return of Rs. 4 Lakhs was generated against less than 1.8 Lakhs in the traditional variety.

TNAU MALAI VAMBU MTP 1 is a large, deciduous and fast growing and multi purpose industrial wood species suitable for packing cases, cigar boxes, ceiling plants, building and construction materials, agriculture implements, pencil, matchbox, kattamarams, tea boxes and plyboard. It is being propagated through seeds and cuttings. This variety can yield 4,329 cft/ha of wood in 5 years. It is also a good fuel wood and the calorific value ranged between 3700 K.cal to 4200 K.cal. The variety was identified as one of the alternate pulpwood species due to its superior pulping qualities viz., basic density 538 kg/m3, pulp yield 50.5% and kappa number 19.6.

It is a large and fast growing and multipurpose industrial wood species suitable for pulp, paper and plywood industries. It is propagated through vegetative prorogation by cuttings. This variety can able to yield 150 tonnes /ha of wood in 5 years under irrigated conditions. Tree can be harvested between 3 and 5 years depending on the industrial utility. It is suitable for both irrigated and rain fed cultivation. The variety has 48 % pulp yield with 19.30 kappa number. The calorific value is 4314 kcal/kg.

This department has developed 27 hybrid derivates of Jatropha hybrids with varying degree of variability in terms of seed and oil yield and associated morphological characters. From these hybrid derivates two distinct hybrids viz., FCRI HC 21 and FCRI HC 32 have been certified as new developed varieties by NBPGR and assigned the new variety number of INGR 09037 and INGR 09036 respectively.

Clonal forestry in tree breeding programmes is one of the emerging area with strong attraction to the traditional seed orchard breeding system. There has been growing interest in using the techniques of clonal forestry where tremendous yield improvement was achieved by adopting the clonal forestry approaches. Accordingly, this department has developed clonal technologies for the following prioritized fast growing industrial wood species to increase the productivity as well as to reduce the rotation.

• Eucalyptus
• Casuarina
• Melia dubia
• Lannea coramandalica
• Melia composite
• Ailanthus
• Bamboo
• Simarouba
• Jatropha Hybrid

The Casuarina clonal plantation needs to be pruned twice the year and during the three year of plantation activities it is expected that 1-2 tonnes of plantation residues in the form of needles are to be available which are currently either unutilized or underutilized. The plantation residues have been successfully value added into briquettes. The economic analysis of plantation residue based briquetting technology has indicated the economic superiority of the system compared to the existing saw dust based technology.