Genetic Diversity in Three Important Agroforestry Tree Species of Dry Zone : a case study

Abstract

Three important tree species viz. Prosopis cineraria ('Khejri'), Albizia lebbek (Desi 'Siris') and Acacia nilotica (Black 'Kikar') have been a part of traditional farming systems, and these are maintained for food, feed, small timber and other minor tree products. An intensive germplasm of these species (8 provenances for P.cineraria, 12 provenances for A. lebbek, 21 provenances for A. nilotica) was collected from throughout their range of natural distribution in India during 1988 -1989. The plantations were raised in replicated plots (75 trees of each provenance) at Hisar, India. All the species showed tremendous provenance variation in growth, fodder quality and nitrogen fixing ability. Large variations suggested that the populations are adapted to a wide range of agro-climatic conditions that prevail in India. The wide range of intra specific diversity has helped to survive these species to much greater biotic and abiotic pressure during the past. Some of the populations of these species are adapted to high level of salts in the soil, and others which possess ability to fix large quantity of atmospheric nitrogen. There are many other potential uses such as providing reforestation and breeding materials, gene cosnervation and historic references. Genetic diversity in these species is of great value for rural development as man-cattle-tree components strongly influence each other.