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University of Agricultural Sciences, Dharwad

The University of Agricultural Sciences, Dharwad was established on October 1, 1986. The University has 5 Colleges, 27 Research Stations, 6 Agriculture Extension Education Centers, 6 Krishi Vigyan Kendras and ATIC. The University has its jurisdiction over 7 districts namely Bagalkot, Belgaum, Bijapur, Dharwad, Gadag, Haveri, and Uttar Kannada in northern Karnataka. Greater diversity exists in soil types, climate, topography cropping and farming situations. The jurisdiction includes dry-farming to heavy rainfall and irrigated area. Important crops of the region include sorghum, cotton, rice, pulses, chilli, sugarcane, groundnut, sunflower, wheat, safflower etc. The region is also known for many horticultural crops. Considerable progress has been registered in the field of education, research and extension from this University.

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  • ThesisItemOpen Access
    REPRODUCTIVE ECOLOGY OF Saraca asoca (Roxb). De Wilde: AN IMPORTANT THREATENED MEDICINAL TREE SPECIES.
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, DHARWAD, 2004) Anjan Kumar, B N; Vasudeva, R
    "Saraca asoca (Roxb). De Wilde, is an economically important medicinal tree species that has been identified as a flagship species for conservation in India because of its threat status. A study was carried out on two natural populations of S. asoca of Uttara Kannada district at Banavasi and Devimane Ghat to understand its breeding system, regeneration and to standardize a vegetative propagation protocol to aid its genetic improvement. S. asoca predominantly blooms during summer and has a large time window of flowering from January to May. This andromonoecious tree bears inflorescence with equal frequency of normal bi-sexual flowers and functionally male flowers (with rudimentary gynoecium), shows a self-incompatibility index of 0.12 and belongs to ""mostly-incompatible"" category. For the first time we have identified floral polymorphism for floral colour (red and yellow morphs), stigma colour (red and yellow morphs) and floral arrangement (compact and loose). These variations may represent a case of balanced polymorphism and are useful as markers. The floral syndrome of S. asoca is typical of ornithophilous species-brightly coloured flowers with sweet fragrance and copious amount of nectar but flexible enough to accommodate opportunistic pollinators such as butterflies. S. asoca produces large recalcitrant seeds typical to wet evergreen forest tree species vv^ith a critical moisture content around 35 per cent. The germination of S. asoca seeds does not require any special pre-treatment. Propagation through non-leafy stem cuttings treated with 2000 ppm Indol Butyric .Acid (IBA) in dust form and placing them in coir pith media resulted in higher per cent rooting among the stem cuttings apart from increasing the number of roots as well as longer lateral roots. The reproductive success of S. asoca is constrained by lack of effective pollinators, narrow anther dehiscence, poor pollen grain viability period, and high level of seed predation by mammals / insects. This has resulted in very poor natural regeneration through seeds (with 0.08 seedlings per adult) and may lead to genetic bottlenecking of populations."