IN VITRO CLONAL PROPAGATION AND PRESERVATION OF GENETIC RESOURCES OF SOME WOODY PLANTS

Abstract

This study was carried as a coordination of Ornamental Horticulture Dept., Fac. of Agric., Cairo Univ. and l11e Timber and Forest Plant Research Dept., Hort. Res. Inst., AR.C., Giza during the periods of 2001 to 2004 aiming to propagate and preserve the explants of some woody trees by in vitro using different treatments. The results obtained for micropropagation of Sequoia sempervirens (D.Don) Endl. showed that, the most effective disinfecting process for shoot tips and nodal cutting e:q>lants was achieved by using chlorox (30%) for 10 min alone or followed by HgCh (0.2%) for 5 min. Also, addition of BA at 0.2 mg r1 alone or with 0.01 NAA increased the survival rate at different seasons, with exception of spring season. Shoot tips ex-plants increased the survival percent and shootlets number per ex-plant significantly during the four seasons of collection compared to nodal cutting, however, spring season was the highest seasons to increase the survival percent. Results of multiplication stage showed that, increasing BA concentration up to 1.0 mg r1, repeat subculture up to three times and culturing the lower part of microcutring on horizontal orientation increased shootlets proliferated number per microcutting compared to using the upper part of microcutting on vertical orientatiOit The length of shootlets decreased with increasing BA concentration during the four investigation seasons. It was obtained that, the highest percent of rooting and the greatest number of root formed per shootlet was recorded by using 7.0 mg r1 AgN03 + 3 g r1 activated charcoal, however, soil mix1Ure of (1:1:1) sand :peat: perlite recorded the maximum survival percent of acclinlizated plantlets and increased the root length.