Micropropagation and conservation of three Juniperus species (cupressaceae)

Shoot tips of three species juniperus excelsa m. bieb,juniperus horizontalis moench and juniperus chinensis l. were initiated to develop rapidly multiplying protocol for large scale micro propagation,regeneration and conservation of these species. the effect of various concentrations of different plant growth regulators on different media was checked to optimize the efficient media for propagation. the young shoot tips were cultured on ms,wpm and n6 media supplemented with different concentrations of iaa,iba,2,4-d in combination with bap. the explants used for callus induction in wpm supplemented with 0.50 mg/l 2,4-d and bap produced best callus. at this concentration rich solid mass of greenish brown callus was produced in all three species. large numbers of shoots were also produced in wpm medium containing 0.50mg/l bap,average shoots produced were j. excelsa 6 shoots (6.1±0.2cm),j. horizontalis 8 shoots (8.2±0.2cm) while significantly high number was produced by j. chinensis with 9 shoots (9.5 ±.0.3cm) in four months time. rooting also started in all species on the same media when plant attained height of 4-7cm but these roots were not good enough to support plantlet. wpm with iaa and iba hormones were used for rooting. best roots were produced in iba at 1.0mg/l. significantly high number of roots were produced in j. chinensis. after proper production of roots in 6-8 weeks plants were acclimatized and shifted to green house. the survival rate after two months of hardening in green house for j. excelsa was 42%,j. horizontalis 68% and for j. chenensis 87%.