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 Pathogen growth in vitro is one of the major problems in plant micropropagation, so the most important stage of in vitro culture of plants is disinfection of the cultures. In the common methods of disinfection, the media and plant materials, apparatus such as autoclaves and chemicals disinfectents are used, which causes the time of this process and the costs to increase. This research objective to improve the disinfection of Iris hollandica cv. Apollo scales using different plant essential oils (thyme, cumin and savory) and the methods of using essential oils as disinfectants, the use of essential oils in the medium and the use of essential oils fumigation was done in four independent experiments. The use of essential oils of thyme, cumin, and savory completely prevented both contamination of the culture medium and contamination of the explant. The best disinfection method was when the essential oils were used in combination with the culture medium. Bacterial contamination was better controlled at concentrations of 0.125 to 0.25%, but the concentration of 0.25% of essential oils resulted in better control of fungal infection. The least browning of iris scale explants was observed at a concentration of 0.125. The technique presented in this study can significantly reduce the cost of electricity and lighting, as well as personnel costs. Therefore, this method can introduce a practical and cost-effective technique for plant micropropagation.

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Strawberry is a valuable, nutritious, and economically important fruit all over the world including Bangladesh. Therefore, there is a demand to develop a suitable variety of strawberry. For this purpose, leaf explants from in vitro grown strawberry plantlets were cultured onto MS medium supplemented with different concentrations and combinations of 2,4-D, NAA and BA for callus induction. The most effective combination was 2.0 mg/L NAA with 0.5 mg/L BA. Then, the calli proliferated in this medium were cultured in MS medium containing different concentrations and combinations of BA, BA + NAA and BA + KIN + NAA for shoot regeneration. The best media combination was 1.5 mg/L BA + 0.75 mg/L NAA + 0.5 mg/L KIN. The regenerated shoots were cultured onto MS medium with different combinations of auxins or in MS and ½ MS medium without plant growth regulators (PGRs). The highest rooting performance was recorded in MS medium without PGRs. The plantlets were then gradually acclimated and successfully transferred to the field for evaluation. Somaclonal variations in different morphological characters such as plant height, no. of leaves/plant, petiole length, no. of stolon/plant, stolon length, no. of nodes/stolon, canopy size, no. of clusters/plant, fruit shape, no. of fruits/plant, average fruit wt. (g), fruit wt/plant (g), were noticed. Some of the somaclones exhibited better performances of the above mentioned characteristics than those of micropropagated mother plants and were well adapted to Bangladesh agro-climatic condition and were cultivated commercially in the winter season by many farmers.

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 Fig trees are threatened by the attack of Fig Mosaic Disease (FMD) on leaves and fruits caused by viruses of several genera. Shoot-tip culture is a convenient method for viral sanitation. For this purpose, a reliable protocol for rapid in vitro propagation was developed with shoot-tips of three major Tunisian local fig (Ficus carica L.) varieties Zidi (ZDI), Soltani (SNI), Bither Abiadh (BA) and one rare and recalcitrant caprifig Assafri (ASF). For each in vitro step, four Murashige and Skoog (MS) media with different combinations of plant regulators were used. The best initiation of shoot-tips with sizes 0.5, 1 and 1.5 mm was obtained on medium M₃ containing 0.2 mg L^-1 Benzyle Amino Purine (BAP), 0.1 mg L^-1 1-NaphthaleneAcetic Acid (NAA) and 0.1 mg L^-1 Gibberellic acid (GA₃). The variety (SNI) showed the highest shoot-tip initiation potentialities for the establishment step with 100% of explant development rate. The shoot multiplication and plantlet development were provided by medium M₆ with 0.5 mg L^-1 BAP and 0.1 mg L^-1 NAA. The highest average of leaf number increase (92 leaves per plant) and proliferation rate (16.91 branches per plant) were reached on M₆. The best rooting rate (83.34%) was favored by medium M₁₁ with half-strength MS and 1 mg L^-1 Indole-3-Butyric Acid (IBA). Ex vitro rooting of fig plantlets was successfully performed on moist peat with success rate of 90%. The acclimatized fig vitroplants showed high establishment rates (92.1%) and rapid growth on substrates S₁ composed by peat without symptoms of virus diseases or morphological abnormalities.