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The present study aimed to induction and detection gene expression in okra calli derived from anther cultures exposed to drought stress and UV-C. Results showed an increase in the mean response % in callus induction using leaf explant of okra (Abelmoschus esculentus) cultured on Murashige and Skoog (1962) medium (MS) supplemented with different concentrations and combinations of Naphthalene acetic acid (NAA), Benzyl adenine (BA) and Thidiazuron (TDZ). Two protocol used to callus induction, the response percentage to callus formation was different and ranged from 10 to 100. In the first protocol of PGRs combinations and concentrations, anther explants responded significantly to the concentration 2.0 mg/L of NAA and 0.5 mg/L TDZ with a mean response 100% for callus induction compared with those cultured on a hormone free medium and other combinations and concentrations of PGRs. On the other hand, the second protocol, showed the highest callus induction in all PGRs combinations recorded 2.0 mg/L of NAA and 3.0 mg/L BA in the mean response % for callus induction. Results showed that the highest callus fresh weight for maintenance medium was achieved at 2.0 mg/L NAA and 2.0 mg/L BA. Results showed that more calli with root being produced but no shoot regeneration or embryogenesis obtained. Callus cultures were subjected to drought stress using different concentrations of mannitol 0.0, 100, 200 or 300 g/L. Cultures were also subjected to UV-C radiation with UV-C 1.5 kJ m-2 for 0, 30, or 60 min then re-cultured on MS medium supplemented with 0.0, 100, 200 or 300 g/L of mannitol. Callus fresh weight was recorded, mean callus fresh weight decreased with increasing mannitol concentration reached 91 mg at 300 g/L mannitol, while reached 198 mg in control. On the other hand, the highest value of callus fresh weight reached 139 mg at the concentration 100 g/L of mannitol only without UV treatment. Reverse transcriptase polymerase chain reaction (RT-PCR) was used for analyzing differences in gene expression in cultures exposed to drought (stressed) and unstressed (control) of okra calli. Mitogen-activated protein kinase (MAPK) gene that encodes for drought tolerance was investigated in okra plant, which can be considered an indicator for drought tolerance, and this gene has not been studied before in the okra plant after searching in the literature. [ABSTRACT FROM AUTHOR]

The present study aimed to induce and detect genetic variation in Abelmoschus esculentus tissue cultures toward drought tolerance. An increase in the mean response % in callus induction using leaf explant of okra (Abelmoschus esculentus) cultured on Murashige and Skoog (1962) medium (MS) supplemented with different concentrations and combinations of Thidiazuron (TDZ), Naphthalene acetic acid (NAA) and Benzyl adenine (BA). The response percentage to callus formation was different and ranged from 10 to 100%. The highest response of callus induction achieved 100% at 3 mg/L NAA supplemented with 0.5 mg/L BA. Results showed that the highest callus fresh weight for maintenance medium was achieved at 2.0 mg/L NAA and 2.0 mg/L BA. Results showed that more calli with root being produced but no shoot regeneration or embryogenesis obtained. Callus cultures were subjected to drought stress using different concentrations of mannitol 0.0, 100, 200 or 300 g/L. Cultures were also subjected to UV-C radiation with UV-C 1.5 kJ m-2 for 0, 30, or 60 min then re-cultured on MS medium supplemented with 0.0, 100, 200 or 300 g/L of mannitol. Callus fresh weight was recorded, mean callus fresh weight decreased with increasing mannitol concentration reached 91 mg at 300 g/L mannitol, while reached 198 mg in control. On the other hand, the highest value of callus fresh weight reached 139 mg at the concentration 100 g/L of mannitol only without UV treatment. Reverse transcriptase polymerase chain reaction (RT-PCR) was used for analyzing differences in gene expression in cultures exposed to drought (stressed) and unstressed (control) of okra calli. Mitogen-activated protein kinase (MAPK) gene that encodes for drought tolerance was investigated in okra plant, which can be considered an indicator for drought tolerance, and this gene has not been studied before in the okra plant after searching in the literature. [ABSTRACT FROM AUTHOR]

Abiotic stress-induced genes may lead to understand the response of plants and adaptability to salinity and drought stresses. Differential display reverse transcriptase - polymerase chain reaction (DDRT-PCR) was used to investigate the differences in gene expression between drought- and salinity-stressed plantlets of Ruta graveolens. Direct and stepwise exposures to drought- or salt-responsive genes were screened in R. graveolens plantlets using the DDRT technique. Gene expression was investigated both in the control and in the salt or drought-stressed plantlets and differential banding patterns with different molecular sizes were observed using the primers OPA-01 (646,770 and 983 pb), OPA-08 (593 and 988 pb), OPA-11 (674 and 831 pb), OPA-17 (638,765 and 1000 pb), and OPA- 15 (645 and 900 pb) indicating the expression of new genes amplified under stress conditions or of genes that already exist. Accordingly, DDRT-PCR seems to be a versatile and sensitive method, capable of detecting transcriptional changes at the mRNA level in plants. [ABSTRACT FROM AUTHOR]

An experiment was conducted with the aim of inducing genetic variation using the mutagen Ethyl Methane Solphonate (EMS) in Chrysanthemum morifoliumsingle nodes grown in vitro. Six concentrations of the mutagen were used (0, 0.5, 1.0, 1.5, 2.0, 2.5 or 3%). Two methods were implemented, either the EMS was dissolved in distilled water or in a buffer solution. Single nodes were soaked for 90 min with continuous shaking in all treatments except control. Results revealed a significant reduction in survival percentage correlated with the lowering of the solution pH. The LD50for the effect of the mutagen was determined in both methods recording 1% of the EMS in nodes soaked in distilled water whereas recorded 1.25% for those soaked in buffersolution. The experiment also investigated the genetic distance in number of mutated samples compared with mother plants using DNA markers with the aid of RAPD-PCR. DNA was extracted, isolated then purified before electrophoresis and implication. Results exhibited that EMS induced genetic variability particularly when single nodes were soaked in buffer solution containing the mutagen. [ABSTRACT FROM AUTHOR]

The present study was established to enhance NaCl tolerance in strawberry (Fragaria x ananassa Dutch) 'Festival' cultivar which is grown widely in Iraq and it is sensitive to salt stress, Leaf explants were treated with Ethyl Methane Sulfonate (EMS) to induce genetic variation and then used for callus induction and shoot regeneration under NaCl stress. Different concentrations of NaCl (0.0, 10, 25, 35 or 45 mM) were dissolved with irrigation water and added to the soil. Response to NaCl was evaluated after three months. Callus cultures were initiated on Murashige and Skoog (MS) medium supplemented with different concentrations of a-naphthalene acetic acid (NAA) and 6- benzylaminopurine (BAP), 4 mg/L-1 NAA+1 mg/L-1 BAP. The regenerated shoots were inoculated on shoot induction medium containing 2 mg/L1 BAP + 0.5 mg/L-1 NAA then transferred to MS medium supplemented with IBA 1.0 mg/L-1 for rooting. Morphological parameters, number of leaves, plant height, vegetative area, number of flowers, number of fruits and weight of fruits were investigated compared with in vivo plants. Genetic variation based on RAPD- PCR technique was used to detect variability. The results showed a high reduction in shoots regeneration and rooting in response to increasing NaCl. Morphological characteristics decreased in response to increase NaCl concentrations as well. However, in vitro regenerated plants derived from leaf discs treated previously with EMS, exhibited better performance in these parameters than in vivo plants at high concentrations of NaCl. Using eight RAPD primers a total number of 15 unique bands resulted after EMS treatment in Festival, while 3 unique bands appeared under NaCl stress. This study revealed that EMS as a chemical mutagen is a promising in enhancing NaCl tolerance. [ABSTRACT FROM AUTHOR]

The current study was carried out with the aim of increasing the production of poly phenols in Coleus blumei plant using elicitation at the intact and cellular levels. The abiotic elicitor used to achieve this aim was sodium chloride (NaCl) at the concentrations 100, 200, or 300mM. Total phenols were estimated in the whole plant and compared with the total phenolic content in callus tissues. They were estimated by Folin-ciocalteu and spectrophotometric methods. Induction and maintenance of Coleus callus was carried out on the Gamborg medium (B5) for 21 days supplied with the growth regulators 0.8 mg.L-1 2,4 dichlorophenoxy acetic acid (2-4-D), 2 mg.L-1 Benzyl adenine (BA) and 0.5 mg.L-1 Naphthalene acetic acid (NAA) by using stem explants as a source for callus induction. Results showed a significant decrease in fresh and dry weights of the vegetative parts and roots in intact plants of Coleus in vivo after treatment with NaCl. The fresh weight decreased to 7.24 g at 300 mMNaCl compared with the control, which recorded 35.87g.while the fresh weight of the roots decreased to1.137g at 300 mMNaCl compared with the control, which recorded 3.73 g.Total phenols in callus cultures accumulated higher polyphenols compared with mother plants after treatment with NaCl. Phenols were also evaluated in both callus tissue and liquid medium and compared with the whole plant and control treatment. The highest value of total phenols was recorded in callus cultures supplied with NaCl which was 429.73 μg.L-1 at the concentration 200mMNaCl in both liquid medium and callus tissues. The intact plants recorded the highest mean in total phenols in plants grown in vivo (68.44) μg.L-1 for NaCl. [ABSTRACT FROM AUTHOR]

The present study was established to enhance NaCl tolerance in strawberry (Fragaria x ananassa Dutch) 'Albion' cultivar, which is grown in Iraq and it is sensitive to salt stress. Leaf explants were treated with Ethyl Methane Sulfonate (EMS) to induce genetic variation and then used for callus induction and shoot regeneration under NaCl stress. Different concentrations of NaCl (0.0, 10, 25, 35 or 45 mM) were dissolved with irrigation water and added to the soil. Response to NaCl was evaluated after three months. Callus cultures were initiated on Murashige and Skoog (MS) medium supplemented with a combination of α-naphthalene acetic acid (NAA) and 6-benzylaminopurine (BAP), 5 mg. L-1 NAA+2 mg.L-1 BAP. The regenerated shoots were inoculated on shoot induction medium containing 2 mg.L1 BAP + 0.5 mg.L-1 NAA then transferred to MS medium supplemented with IBA at 1.0 mg.L-1 for rooting. Chlorophyll content and peroxidase concentration were investigated compared with in vivo plants. Genetic variation based on RAPD-PCR technique was used to detect variability. The results showed a high reduction in shoots regeneration and rooting in response to increasing NaCl. Chlorophyll content decreased in response to increasing NaCl concentrations while peroxidase concentration increased. However, in vitro regenerated plants derived from leaf discs treated previously with EMS, exhibited better performance in these parameters than in vivo plants at high concentrations of NaCl. Using eight RAPD primers, a total number of 7 unique bands resulted after EMS treatment while 9 unique bands appeared under NaCl stress. This study revealed that EMS as a chemical mutagen is a promising in enhancing NaCl tolerance. [ABSTRACT FROM AUTHOR]

Many experiments were designed to induce and increase the production of some secondary metabolites in tissue cultures of Hypericum triquetrifoliumTurra using some biotechnological approaches. Callus was initiated on leaf discs cultured on MS medium supplemented with thidazirion (TDZ) at the concentrations 1.0, 1.25, 1.5, 2.0, or 2.5 mgL-1 and indole-3-acetic acid (IAA) at 0.5 mgL-1; callus was also initiated on stem explants on MS medium supplemented with 1.25 mgL-1 6-benzyl-aminopurine (BAP) and 0.5 mgL-1 of IAA. HPLC was used to determine the type and quantity of secondary metabolites in comparison with standards. Phytochemical accumulation in suspension cultures derived from leaf (LCs), stem (SCs) and root (RCs) were investigated. Fungal extracts of Aspergillus niger, Fusarium oxysporum and commercial yeast were added to a liquid MS medium at 0.1, 0.25, 0.5 or 0.75 mgL-1. Data showed that the yield of p-OH-benzoic acid and chlorgenic acid in LCs treated with 0.5 mgL-1 yeast extract increased significantly compared with the control. Caffeic acid and tannic acid decreased in LCs significantly after elicitation with all biotic elicitors, but catechin accumulation in LCs increased significantly, when A. niger extract was added at all concentrations. Rutin, hypersoid and quercitin production in SCs increased significantly when treated with the fungal elicitors; A. niger, F. oxysporum and yeast extracts. Chlorgenic decreased significantly in SCs, after the addition of all biotic elicitors at different concentrations. [ABSTRACT FROM AUTHOR]

In an attempt to differentiate and study one of the most popular medicinal plants (Rosmarinus officinalis L.) grown in the North East region of Iraq, a number of experiments were carried out to differentiate between subspecies available in Kurdistan Province at the morphological and molecular levels. A survey and morphological study was conducted on these subspecies of rosemary in Erbil and Sulaimania governorates. It was found that there are morphological differences in leaves, flowers, shoot growth directions, number of branches, leaf size and shape, accordingly two subspecies were identified and marked as class A and class B of R. officinalis in North East of Iraq. Subspecies A was characterized by a straight shoot growth, dark green leaves and whitish blue flowers while subspecies B has random growth, green leaves and white flowers. In order to investigate the genetic variation, the DNA was isolated and purified from the two subspecies, and then electrophorized using agarose gel. Chromosomal DNA appeared as a clear smear on gel for both A and B. Six types of restriction enzymes were used to digest the genomic DNA for both subspecies A and B, namely EcoRI, EcoRV, BamHI, HindIII, SalI and SmaI. Resulted genomic DNA was amplified using PCR technique for ribosomal DNA (rDNA) as the target sequence, of 668 bp which includes 18S, 5.8S and 26S RNA genes separated by two ITS regions that represent the non-coding sequence of interest for subspecies identification. It is concluded that there are obvious genomic differences in the rDNA in both subspecies, according to the recognition sites availability of restriction enzymes in template DNA, as there was cleavage sites for each one of EcoRV, BamHI, HindIII and SalI in rDNA sequence of subspecies A, while no one of the six restriction enzymes cleavage sites used was present in subspecies B. [ABSTRACT FROM AUTHOR]