الفهرس 
TranspirationOnly 14 pages are availabe for public view
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Abstract
Mohamed Ismail Gainal El-Din · Diab. Evaluation and Propagation of some woody tree hybrids by
using Tissue culture technique for controlling some environmental stresses. Unpublished master of
Science, Ain Shams University, Institute of Environmental Studies and Research, Environmental
Agricultural Science Department 2000.
The main objective of this investigation was to propagate some superior lines of three Eucalyptus
species by using tissue culture techniques and to evaluate transpiration of their in vitro formed
plantlets. The species used are Eucalyptus camaldulensis, E. botryoides and E. rudis.
The results showed that liquid modified MS medium supplemented with 0.5 mg/L BA and 0.1 mg/L NAA
was the best medium for the establishment of shoot tip and stem segment explants. Autumn was the
most suitable time for collection of shoot tip and stem segment explants of E. camaldulensis and
E. rudis. Stem segment during this season gave the highest survival percentage (88.9%) and (88%)
for shoot tips and (62.1% and 60%) for stem segment, respectiv ly. However, Summer was the best
season for shoot tip and stem segments of E. botryoides giving 46.7% and 70.97% survival
percentage.
Autumn and Summer may be optimum time for
explants collection since they represent the active growing season when low levels of endogenus
phenolic compounds are found in the explants.
The main number of proliferated buds per explant of
Eucalyptus camaldulensis reached the highest value 5.7 on
MS medium contammg 0.5 mg/L BA+ 0.1 mg/L NAA. However, E. botryoides. and E. rudis on MS medium
supplemented with 0.1 mg/L BA:±.O..Ol mg/L NAA gave 6.2 and 8.6 buds/explant, respectively. Shoot
elongation of E. camaldulensis gave the maximum increase in the mean length of axillary shoots
(0.61 em) on MS medium+ 1.0 mg/L BA + 2.0 mg/L 2ip+ 0.05 mg/L NAA.
For rooting o( Eucalyptus camaldulensis and E. botryoides, the highest rooting percentage (90%,
70%), the mean number of roots (8.22, i57) and the mean length of roots (4.75 em, 2.32 em),
respectively when cultured on half-strength MS supplemented with IBA at 1.0 mg/L + 3.0 giL
activated charcoal. While, in case of E. rudis the highest · rooting percentage (80%), the mean
number of roots (3.50) and the mean length of roots (2.59) were achieved by using half-strength MS
medium containing 2.0 mg/L IBA + 3.0 g/L activated charcoal.
The evaluation for the plantlets of E. camanldulensis,
E. botryoides and E.rudis is based essentially on the measurement of its capability for
transpiration. E. rudis haying high transpiration rate followed by E. camaldulensis and then E.
botryoides.