EFFECT OF SOME GROWTH REGULATORS APPLIED TO A MULTIPLICATION AND ROOTING MEDIA ON MICROPROPAGATION AND ACCLIMATIZATION OF SOME CULTIVARS OF Rosa hybrida L.

The present research was carried out to study the effect of BAP at 0.25, 0.50, 1.00 and 2.00 mg/l concentrations added to the multiplication medium and IAA at 0.1, 0.3, 1.0 and 3.0 mg/l concentrations applied in rooting medium on the in vitro micropropagation and acclimatization under greenhouse conditions of Rosa hybrida L. plants.  The rose cultivars used in this research were namely Athena, Diana and Red Success.
To evaluate the adaptation degree of different rose cultivars to culture medium composition, the shoot tips (15 – 20 mm length) were surface sterilized and cultured on the modified Quoirin & Lepoivre (1977) medium used as proliferation medium supplemented with casein hydrolysate (1.0 g/l), sucrose (30.0 g/l), Difco agar (8.0 g/l), gibberellic acid (GA₃) (1.0 mg/l), BAP (1.0 mg/l) and IAA (0.3 mg/l).  The proliferated shoots were excised and cultured on multiplication and rooting media.  The obtained results indicated that Red success rose cv. were the best to produce the highest rate of shoot proliferation, shoot multiplication, rhizogenesis values and survival percentage followed by Diana rose cv., while Athena rose was the lowest in this respect. 
The obtained results showed that the best shoot multiplication was achieved in the culture medium containing 6-benzylaminopurine (BAP) (1.0 mg/l) and indole-3-acetic acid (IAA) (0.5 mg/l) which produced the highest survival percentage, shoot initiation occurred within a few days, the highest percentage of explants which formed shoots, the highest number of multiplied shoots and the tallest multiplied shoots per explant.
The obtained results also indicated that the BAP concentration of the shoot multiplication medium affected rooting and survival percentages in the next stage of culture.  Shoot tips formed on media which containing 0.25 and 0.50 mg/l BAP rooted and acclimatized better than shoot tips formed on media containing 1.0 and 2.0 mg/l BAP.
Moreover, rooting of multiplied shoots was achieved on the same medium used in multiplication stage except for the macroelements of Quoirin & Lepoivre (1977) medium used at half strength and sucrose at 20 g/l and IAA (0.3 mg/l) which produced the highest rooting percentage, the highest number of roots per explant and  the tallest roots per explant.  The obtained results also revealed that fewer amount of IAA (0.1 mg/l) in the rooting media significantly improved plantlets acclimatization, and subsequently transferred to a mixture of peatmoss and perlite (3:1 v/v) to greenhouse.  The rooted plantlets survived Successfully and grew into normal plants.