Kher, RaviKour, Kiran2017-08-232017-08-232006No. of references 192http://krishikosh.egranth.ac.in/handle/1/5810029464The present investigations were carried out at the Tissue Culture Laboratory, Faculty of Agriculture, Sher-e-Kashtnir University of Agricultural Sciences and Technology, Udheywalla, Jammu during the year 2004-2006 to study the various aspects of in vitro propagation of Citrus spp. The nodal segments of 2-3 weeks old newly grown flushes from 10-12 year old mature trees were used as explant. Two step sterilization procedure involving 70 per cent ethanol and 0.1 per cent mercuric chloride for 30 seconds and 8 minutes respectively, resulted in maximum per cent culture establishment and minimum contamination in both C. jambhiri and C. sinensis cv. Mosambi. The time taken for culture establishment was less and per cent culture establishment was more in BAP 1.5 mg/l with malt extract for C. jambhiri, whereas BAP 1.0 mg/l with malt extract 500 mg/l proved to be best for C. sinensis cv. Mosambi. In Citrus jambhiri, BAP 1.0 mg/1 in combination with malt extract 500 mg/1; BAP 1.5 mg/1 with malt extract 500 mg/1 and BAP 1.5 mg/1 along with Kinetin 0.5 mg/1 showed 100 per cent multiple shoots in all the cultures during proliferation. However, BAP 1.5 mg/1 with 500 mg/1 malt extract showed the maximum number of shoots per culture (5.34), while maximum length of longest shoot (2.31 cm) and more number of leaves (9.31) on longest shoot were recorded in BAP 1.0 mg/1 with malt extract 500 mg/1, whereas in case of Mosambi BAP 0.5 mg/1 with malt extract 500 mg/1; BAP 1.0 mg/1 with malt extract 500 mg/1 and BAP 1.0 mg/1 in combination with Kinetin 0.5 g/1 showed cent per cent multiple shoots during proliferation. BAP 1.0 mg/1 with malt extract 500 mg/1 showed maximum number of shoots and more number of leaves on longest shoot. The combination of BAP 1.5 mg/1 with malt extract 500 mg/1 showed maximum multiplication of shoots in all the three continuous sub-culturing done at 6 weeks interval in C. jambhiri, whereas BAP 1.0 mg/1 along with malt extract 500 mg/1 resulted in highest shoot multiplication in C. sinensis cv. Mosambi during sub-culturing. The MS medium (half-strength) supplemented with 1BA with NAA, 1.0 mg/1 each, and gelled with agar 0.4 per cent took lesser days for root initiation (16.51) with highest rooted culture 83.33 per cent, while more number of roots per shoot 2.47, maximum length of longest root and shoot and more number of leaves per shoot (4.67) were recorded in same combination in C. jambhiri. Agar (0.4 per cent), sucrose (3.0 per cent) and pH 5.8 were proved to be best for rooting of C. jambhiri plantlets. Covering the plantlets with glass beaker individually and kept in AC culture room proved to be the best hardening treatment, whereas a combination of soil:sand:FYM (1:1:1) was the best potting mixture as this resulted in the maximum survivability (93.33 per cent), height and more number of leaves per plantlet. Glycerol 50 per cent was proved to be the best anti-transpirant as it resulted in maximum per cent plant survival (83.33 per cent). The unit cost of plantlet upto polyhouse stage, based on the 1,00,000 plantlets capacity of the production unit was estimated to be Rs. 2.54, whereas the estimated production cost of a field-grown seedling of C. jambhiri was Rs. 4.48.ennullThesis