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1

Rapid plant regeneration and analysis of genetic fidelity in micropropagated plants of Vitex trifolia: an important medicinal plant

100%

Ahmad N. , Javed S. B. , Khan M. I. , Anis M.

Acta Physiologiae Plantarum

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2013

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tom 35

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nr 08

EN

An efficient in vitro regeneration protocol of a valuable medicinal plant, Vitex trifolia has been successfully established using nodal segments as explants. Three different cytokinins (BA, Kn, 2iP) and auxins (NAA, IAA, IBA) in different concentrations and combinations, evaluated as supplements to Murashige and Skoog’s medium showed to have a marked influence on the regeneration output. Among all the single cytokinin treatments MS medium supplemented with 5.0 μM BA produced the maximum number of shoots yielding 8.20 ± 0.37 shoots per explant with 4.8 ± 0.43 cm shoot length after 8 weeks of culture. Combined with low auxin concentrations, all the three cytokinins at their optimal concentrations synergistically enhanced the regeneration credentials. However, MS medium enriched with 5.0 μM BA and 0.5 μM NAA yielded the best possible regeneration in the species with a regeneration percentage of 97.33 ± 2.67 % and amounting to 16.80 ± 0.58 shoots per explant with 6.20 ± 0.25 cm mean shoot length at the end of 8 weeks in culture. Ex vitro rooting of in vitro derived microshoots was achieved by 20 min 500 μM IBA treatment followed by transfer to thermocol cups containing sterile soilrite. A 95 % plantlets survived acclimatization procedure to the field. Genetic conformity of the regenerated plants was established through RAPD. All the bands visualized on agarose gels were monomorphic with that of the donor plant indicating the clonal nature of the regenerants.

2

Efficacy of ivermectin against cattle warbles in Pakistan

100%

Khan M. Q. , Afzal M. , Khan M. I.

Acta Parasitologica

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1997

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tom 42

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nr 3

EN

Efficacy of ivermectin against cattle warbles was studied in an endemic area of Pakistan. A total of 229 cattle of three breeds and different ages were divided into two groups; treated and untreated control. Treated group was given ivermectin s/c at the rate of 200 µg/kg body weight during the 1st week of September. None of the treated animal developed warbles. Warbles were seen in 23,8% of untreated control animals. Statistically non-significant differences were seen amongst different breeds and age groups. The seasonality of warbles is discussed.

3

Effects of 2,4-dichlorophenoxyacetic acid combined to 6-Benzylaminopurine on callus induction, total phenolic and ascorbic acid production, and antioxidant activities in leaf tissue cultures of Crataegus azarolus L. var. aronia

63%

Chaabani G. , Tabart J. , Kevers C. , Dommes J. , Khan M. I. , Zaoui S. , Chebchoub L. , Lachaal M. , Karray-Bouraoui N.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 02

EN

The present research work describes the effects of 2,4-dichlorophenoxyacetic acid (2,4-D)/Benzylaminopurine (BAP) ratio on callus induction, total phenolic and ascorbic acid production, and antioxidant activities in leaf-derived calli of Crataegus azarolus (hawthorn). The supplementation of 1.0 mg/L 2,4-D and 1.0 mg/L BAP to MS medium was found to be the most efficient for callus induction (as percentage and fresh weigh). The results of biochemical analysis showed that the highest total phenolic contents were obtained in callus cultured on MS medium supplemented with 2.0 mg/L 2,4- D and 1.0 mg/L BAP (52 – 0.56 mg GAE/g DM) and were significantly lower than those of intact leaves (76 – 1.72 mg GAE/g DM). However, the highest ascorbic acid contents were found in callus cultured on MS medium supplemented with 1.0 mg/L 2,4-D and 0.5 mg/L BAP (0.96 – 0.13 mg AAE/g DM) and these amounts were statistically similar to those found in leaf tissues (0.74 – 0.07 mg AAE/g DM). Antioxidant activities of callus extracts were determined using two TEAC assays and results showed that extract of callus cultured on MS medium supplemented with 2.0 mg/L 2,4-D and 1.0 mg/L BAP have the greatest antiradical activities against DPPH (124 – 2.92 mg TE/g DM) and ABTS (0.19 – 0.02 mg TE/g DM) compared to the leaves of field-grown plant. Thus, the use of high level of 2,4-D over BAP can be suitable to enhance the quality more than the quantity of bioactive compounds in leaf callus culture of hawthorn.

4

Change in total phenolic content and antibacterial activity in regenerants of Vitex negundo L.

63%

Ahmad N. , Khan M. I. , Ahmed S. , Javed S. B. , Faisal M. , Anis M. , Rehman S. , Umair S. M.

Acta Physiologiae Plantarum

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2013

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tom 35

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nr 03

EN

A valuable medicinal plant, Vitex negundo L. has been investigated for its regeneration potential using shoot tip explants. Out of a range of concentrations of cytokinins [6-benzyl adenine (BA), 6-furfurylaminopurine, 2-isopentenyl adenine] used as supplement to Murashige and Skoog medium (MS), BA at 5.0 μM concentration proved best for multiple shoot induction yielding 3.60 ± 0.50 shoots after 8 weeks of culture. Inclusion of a low concentration of an auxin with optimal cytokinin concentration favoured shoot multiplication and the optimum response was observed on MS medium supplemented with BA (5.0 μM) along with a Naphthalene acetic acid (0.5 μM), where 65.0 ± 1.73 % cultures responded with a mean number of 4.80 ± 0.58 shoots per explants after 8 weeks of culture. Ex vitro rooting of in vitro derived microshoots was achieved upon dipping the cut ends of microshoots in 500 μM indole-3-butyric acid for 10 min followed by transfer to thermocol cups containing sterile soilrite. About 95 % of the plantlets survived the acclimatization procedure and were transferred to greenhouse and finally to field. Screening of the antibacterial activity and estimation of total phenolic content of ethanolic extracts of micropropagated plants were also carried out and compared with that of the mother plant.