الفهرس 
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Abstract
The Salvia officinalis L. plants genus which belongs to the Labiatae family is a widest-spread attractive aromatic plant. It is has been used for their medical properties since old civilization and recently described on many pharmacopoeias throughout the world. Salvia herb traditionally used as a carminative, antiseptic/bactericidal, spasmolytic, mouthwash against its inflammation, a wound-healing agent, in skin and hair treatment; and against rheumatism and sexual debility in treating mental and nervous conditions, as well as, an insecticidal.
Water deficit and salinity are major stresses that affect plant growth. Drought and salinity are expected to cause salinization of more than 50% of all arable land by 2050. Moreover, the production and productivity of numerous crops are badly affected by these two stresses as they are responsible for enormous economic crop losses worldwide. Drought refers to the meteorological events and should be reserved for field-grown crops. In future plant growth models assume that drought stress will be more severe. Salinity has been a threat to agriculture in many parts of the world. Moreover, the salinity problem has been increased by the requirement of crop irrigation in arid and semiarid environments. No, doubt soil salinity is one of the most environmental abiotic stresses that restrict agricultural productivity worldwide.
Drought and salinity restrict the plant normal growth and disturb the plant water relations. Plants adapted have many complex physiological and biochemical responses which ranged from cellular base to whole organism levels. Plants have complicated mechanisms to alleviate drought and salt stress, such as reduced water loss, increased water uptake, and smaller and succulent leaves to reduce transpirational loss. Low-molecular-weight osmolytes, comprising amino acids and organic acids, total soluble sugars also, play important roles in sustaining cellular functions under drought.
Plants suffering from abiotic stress are commonly facing an enhanced accumulation of reactive oxygen species (ROS) with damaging as well as signaling effects at organellar and cellular levels. The outcome of an environmental challenge highly depends on the delicate balance between ROS production and scavenging by both enzymatic and metabolic antioxidants. Therefore, antioxidant enzymes have an important role as a protective mechanism against free radical groups.
An efficient approach for the selection of specific characters is a vital step in plant breeding programmers. In vitro selection can be employed as a substitute procedure, wherein the rapid clone selection could be done in a limited space and under controlled conditions voiding the biotic and abiotic effects that could negatively interfere with selection. Nodal and leaf explants were cultured on MS medium supplemented with different combinations of TDZ, BA or Kin as a source of cytokinin and IAA or 2,4-D as an auxin. Supplemented growth medium with TDZ promoted callugensis of both types of explants however, callus did not develop when the medium contained only BA or Kin. Number of developing shoots was significantly varied among concentration of PGRs. Nodal explants cultured on medium with 1.5 mg/l TDZ + 0.1 or 0.5 mg/l IAA had the highest significant shoot number (7.2 shoots/explant) followed by IAA + TDZ at 1 mg/l which developed 5.5 and 5.8 shoots/explant, respectively. In many cases the adventitious shoots failed to develop into shoots even after subculture. The tallest shoots 9.6 cm were observed on medium with 1 mg/l of BA or Kin + 0.5 mg/l IAA. Adventitious shoots were perceived for all leaf explants that cultured on medium supplemented with (TDZ + IAA) and (1 mg/l TDZ + 0.1 mg/l 2,4-D). Leaf explants cultured on medium supplemented with 1.5 mg/l TDZ + 0.1 or IAA had the highest significant shoot number (8 shoots/explant) Unlike TDZ, Kin and BA had low efficiency to sustain shoot growth as the number of developing shoots was 0.4/explant.
Therefore, an efficient protocol was successfully established for the regeneration of plantlets from single node or leaf explants of S. officinalis. A preliminary experiment was carried out to optimize the NaCl and mannitol concentrations which could be used as a selective agent. Single nodes were cultured on SGM enriched with 0, 25, 50, 75, 100, 125, 150 mM of NaCl (for NaCl- selection) and 0, 50, 100, 150, 200, 250, 300, 350, and 400 mM (for mannitol selection). For each treatment there were 6 jars each with 5 explants. Explants were transferred onto a fresh medium every 4 weeks. After 8 weeks, the ability of explants to show new growth, rooting%, and the FW and DW (after drying at 70°C) of both shoots and roots were measured. On the base of ability of explants to show new growth as well as, shoots and roots FW and DW this experiment showed that NaCl at 100 mM and mannitol at 300 mM could be used as a selective agent.
Following that achievements leaf explants as well as 1-month and 4- month old shoot clumps which regenerated from leaf explants on MS medium enriched with 0.1 mg/l IAA + 1.5 mg/l TDZ were used for in vitro selection a NaCl or mannitol tolerant clones. These materials were subcultured on the same medium supplemented with 100 mM of NaCl or 300 mM mannitol. All leaf explants and 1-month old shoot clumps did not survive get brown and died. On the other hand, all shoot clumps cultured on medium with 300 mM mannitol had normal growth with no sign of necrotic or damage due to mannitol. Therefore, this experiment was repeated using 350 and 400 mM of mannitol.
After 4 months 4 shoots were recovered from 60 cultured shoot clumps on medium with 100 mM NaCl. These shoots were elongated and individually cloned on MS medium enriched with 0.5 mg/l IAA. Single nodes of the recovered clone, as well as, the control plants were cultured using a single node explants on MS medium enriched with 0.5 mg/l IAA and 0 or 100 mM NaCl. After 8 weeks of growth on this medium statistical analysis showed significant difference between NaCl concentrations and among the selected clones and the control plants on the base of the ability to develop new growth, plant height, shoot and root FW and DW as well as, chlorophyll content measured using SAPD unit. Moreover, there were significant differences among the selected colons on proline and TSS and TSP content. Also, some regenerated clones showed higher activity of the free radical scavenging enzymes; CAT, APX and POX under salt stress.
Regarding the mannitol stress, out of 72 shoot clumps cultured on medium with 400 mM mannitol 7 shoots were selected. Shoots were individually cloned. selected clone as well as control non-selected plantlets were assessed for their ability to grow on medium with 0 and 400 mM mannitol. All control plants did not show any new growth which confirm the previous obtained results which showed that S. officinalis could not grow on medium enriched with 400 mM mannitol. There was a significant effect of mannitol on the growth, chemical composition and antioxidant activity of S. officinalis plantlets.
There was a significant variance among the selected clones and control plant for most investigated traits on free- mannitol medium. Under stress condition results showed a significant variance among clones on the ability to show new growth, shoot FW and DW and proline and TSP content. But it seems that TSS did not play a vital role for osmotic stress defense. Antioxidant enzymes, CAT, POX and APX analysis of variance showed significant variations on their activity. Yet, the activity of POX was clearer than the other two enzymes some plantlets had significantly higher activity of APX under stress condition, other had lower activity and on some cases there was no change on the activity due to mannitol stress.
Therefore, somaclonal variation was used to select a salt and drought tolerant S. officinals clones. Moreover, some physiological mechanisms that are crucial for salt stress tolerance were underlined. However, the behavior of the selected clones under field condition as well as the effect of stress and in vitro condition should be assessed. Moreover, stability of the salt or osmotic tolerance of selected clones should be considered on future study.