Seed Health Management for Better Productivity - Govind Ballabh ...

(Seed Health Management for Better Productivity)Production of Quality Seed in Tree SpeciesSalil TewariDepartment of Genetics and Plant Breeding, G.B.P.U.A.&T., Pantnagar-263145 (Uttarakhand)Nature has endowed India with vast forest wealth of great diversity, having from tropicalevergreen forests to dry alpine forests. There are about 15,000 species of flowering plants, thewoody vegetation constitute about 2,486 tree species of angiosperms (2,417 dicotyledons and 69monocotyledons) and 21 gymnosperms. Increase in the pace of industrialization afterindependence, coupled with a tremendous growth of human and livestock populations, placedenormous pressure on forests, resulting in their depletion at a fast rate. Now there is a large gap indemand and supply of the various forest products. The National Forest Policy, 1988, places greatemphasis on the maintenance of environmental stability through preservation of forests andconserving natural heritage.Tree improvement consists of a “marriage” of silviculture and tree parentage to obtain thegreatest overall returns. Tree improvement has an important role in Forest Management whenproduction of high volumes of good quality timber or non-timber forest products is the principalmanagement objective (Zobel and Talbert, 1984). Success in the establishment and productivity offorest tree plantations is determined largely by the species used and the source of seed withinspecies. The most successful tree improvement programs are those in which proper seed sourcesand provenances are used. Research has shown that if forests are to be of increased valueincluding the aspects of stability, adaptation, resistances, productivity and diversity, it is necessaryto use reproductive material, which is genetically and phenotypically suited to the site and is ofhigh quality.At present, most of the genetic material (seeds/planting stock material) used inforestry sector in India is obtained from unspecified sources, from stands, natural or planted, whichare neither classified nor managed specifically for seed or planting stock material production.A typical tree breeding programme primarily consists of selection of phenotypically superiortrees, utilizing desirable genes, mass multiplication of improved planting materials, andmaintaining a population with broad genetic base for advanced generation breeding. Detailedknowledge of genetic principles, species biology, past history of selection, and the economicimportance of the trait to be improved is a prerequisite for implementation of such a dynamicprogramme. All tree improvement programmes should have dual objective of (1) obtainingimmediate genetic gain in terms of better quality, wide adaptability and higher productivity and (2)maintaining broad genetic base for continued improvement over many generations. Maximumgains are achieved by the judicious use of a very few best parents (elite trees) to supply plantingstock in operational forestry programme. Following sections describe basic principles of plus treeselection and their utilization.India has been at the forefront since organized research in agroforestry started worldwide.The All India Coordinated Research Project (AICRP) on Agroforestry with 20 centers all over- 139 -