الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
This study was conducted at. Tissue Culture Laboratory,
Horticulture Department, Faculty of Agriculture, Moshtohor during
the period started from 1995 till 1997. This investigation was done to
formulate the best suitable balanced medium for induction. large
I • number of healthy. homogenous, and similar to mother trees during
exact time with low expenses and reducing costs of importation.
Shoot-tips and one-nodal cuttings of communis pear and MJ\1-
106 apple rootstock were collected at different quarters of year
round, washed, sterilized and cultured on different medium types,
states, and strengtns. Also, different anti-oxidant treatments were
involved. Besides, medium state, cytokinin types, and
concentrations as well as different thidiazuron concentrations were
evaluated. Meanwhile, different medium strengths and GA3
concentrations were tested. Furthermore, different auxin types and
concentrations. medium states and darkening treatments were
studied.
!. IV.I. Establishment stage: ’
The results can be summarized as follow: -
1- Solidified Murashige and’ Skoog medium for communis pear,
and Lepoivre medium for MMI06 apple rootstock showed the
most suitable ones for~decreasing and increasing necrosis,
explant development and ~i rning.
2- Shoot-tips surpassed one-nodal cuttings in reducing necrosis and
increasing explant development and greening of both communis
pear and M:M-106 apple rootstock.
3- The best collection date for communis pear explants
accomplished during the first quarter, which involved April,
May and June. However, MM-I06 apple rootstock explants
collection was most suitable during the fourth quarter (January,
February and March).
4- The accumulated phenolic compounds in both communis pear
and MI\f-106 expl ants , which caused oxidation and finally the
death of the established explants, were greatly reduced when the
combination of anti-oxidant solution plus PVP was used
followed by PVP alone.
5-Activated charcoal had an adverse effect during establishment
stage on explant development and greening of either communis
pear or ~fM-I06 apple explants.
6- Full and one-half medium strengths of either Murashige and
Skoog for communis pear or Lepoivre medium Tor MM-I06 :
apple were the most effective medium strengths for enhancing
t
shoot regeneration and greening parameters.
IV.2.Proliferation stage:
1-Semi-solid medium encouraged the highest possible
protferation and necrosis of both studied rootstocks.
-if
2- Kinetin surpassed 6-benzylaminopurine in enhancing growth
and greening. However, the reverse was true in case of
proliferation and necrosis.
3- The best growth and greening were achieved by
supplementation of the culture medium with 2 mg/L. 6-
benzylaminopurine, while this effect was more clear in
proliferation when 4 mg/L. BAP was used for both communis
pear and l\’IM-I06 apple rootstocks.
4- Thidiazuron was effective in reducing necrosis and increasing
growth, proliferation, and greening when added at lower
concentrations i.e. 0.5 or 1.0 mg/L., while higher concentrations
2.0 or 4.0 mg/L. had a lethal effect on the cultured explants
under investigation.
IV.3. Rooting stage:
IV.3.t. Shoot elongation:
1-Shoots elongation of either commurus or MM-106 apple
rootstocks as well as greening and root initiation increased
greatly by using full or one-half medium strengths.
2- Gibberellic acid at 4.0 mg/L. enhanced a noticeable ihcrease in
shoot elongation in both used plant types, while greening and
growth showed improvement by adding either 2.0 or4.0 mg/L.
GA3 to the culture medium.
II
IV.3.2. Root formation: ~-----------~
1-Indcle-S-buty TIC acid encouraged formation of callus and
increased necrosis. However, IBA and NAA succeeded in
enhancing rooting of communis pear plantlets.
2- Best rooting of communis pear was noticed when 1.0 mg/L. IBA
was added to the culture medium.
3- Solid and liquid medium states induced best growth, while
liquid medium promoted the best rooting of communis pear.
4- Surface or outer coverage and the combination between ~¥
them enhanced the highest root formation. However, callus
increased by all darkening treatments under investigation.