Search

Copyright of Jordan Journal of Agricultural Sciences is the property of University of Jordan and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hairy nightshade Solanum villosum (L.) Mill. is a promising medicinal plant that grows wild as a weed in Jordan. Tissue culture approach was utilized for micropropagation and acclimatization of this plant to insure its stable availability for phytoindustry and research. In vitro shoot multiplication was examined by exposing the nodal segments to 6-benzylaminopurine (BA), 6-(gamma,gamma-Dimethylallylamino) purine (2ip), 6Furfurylaminopurine (kinetin) or Thidiazuron (TDZ) at levels of (0, 0.5, 1.0 or 1.5 mg/L) plus 0.1 mg/L αnaphthaleneacetic acid (NAA). Meanwhile, different rates (0, 0.5, 1.0 or 1.5 mg/L) of Indole-3-butyric acid (IBA), Indole-3-acetic acid (IAA) and NAA were added to the media to enhance microshoots rooting. Moreover, direct regeneration was experimented by exposing the leaf discs to various hormone combinations under light conditions. The results revealed that a satisfactory shoot multiplication was obtained when either TDZ or BA was added to the MS media, and the maximum number of the new shoots per explant (more than 30 shoot/ explant) was recorded in nodal segments treated with (1.5 mg/L) TDZ with an average height of (2.0 cm). Best rooting (12 roots/ explant) with average root length of (2.39cm) was obtained in microshoots cultured on (1.5 mg/L) IBA. Also, direct shoot regeneration was obtained only in hormone combinations that consisted of BA and NAA, while best shoot regeneration rate (85%) and shoot number (6.9 shoot/ leaf disc) were recorded in leaf discs treated with (0.5 mg/L BA + 0.1 mg/L NAA). Moreover, all potted plantlets were successfully acclimatized, and (100%) survival rate was recorded in all plants one month after being transplanted to greenhouse conditions. [ABSTRACT FROM AUTHOR]

Copyright of Jordan Journal of Agricultural Sciences is the property of University of Jordan and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ziziphora tenuior L. is one of the important medicinal plants that belong to the Lamiaceae family. It is a rare species with a promising medicinal potential and grows wild in the southern part of Jordan. Unfortunately, this plant might be totally extinct from the wild due to over-exploitation. Two cryopreservation techniques (encapsulation-dehydration and encapsulation-vitrification) were applied for in vitro conservation of this valuable medicinal plant, and after that the explants were tested for their genetic stability using Amplified Fragment Length Polymorphism (AFLP) technique. In the encapsulation-dehydration experiment, the results revealed that 40% of the cryopreserved shoot tips survived when they were dehydrated chemically on 0.75 M sucrose in MS supplemented media for one day and exposed to air dehydration for 6 hrs. Moreover, the best recovery rate (20%) was obtained when either 0.5 M or 0.75 M sucrose MS supplemented media were used as preculture media for the shoot tips for one day, followed by air dehydration for 4 or 6 hrs. Meanwhile, in the encapsulation-vitrification experiment, the highest survival (37.5%) and recovery (10%) percentages of the cryopreserved shoot tips were obtained when the encapsulated shoot tips were pretreated for 60 min. with the loading solution before being exposed to PVS2 vitrification solution and LN. AFLP technique had clearly showed that, there were no genetic variations between the shoot tips of Ziziphora tenuior L., before and after cryopreservation. [ABSTRACT FROM AUTHOR]

Medicinal and aromatic plants are those containing special chemical components that enable them to relief pain, release pleasant aromas, and improve food flavors. Meanwhile, medicinal and aromatic plants are under real jeopardy due to the uncontrolled collection of these plants as a result of being extensively used in herbal medicine and food industry. So conservation action for these natural resources is of high priority. Plants conserved under in situ conservation conditions are exposed to natural disasters, pests and pathogens in addition to the fluctuating government policies. Also ex situ conservation is very difficult to be applied as adequate samples have to be collected for the conservation of genetic diversity. In vitro conservation is offering a strong and a multi package of techniques that do so good when other conservation methods are not feasible. Slow growth conservation is a very simple in vitro technique based on reducing the growth rates of the tissue cultured plant for short or mid- term storage and yet increasing the intervals between subcultures. In this conservation type, several techniques are used separately or in combinations to slow down the growth rate of the stored explants, such as, addition of elevated levels of osmotic agents or ABA in addition to storage under minimal growth conditions such as low temperature and dark incubation. Cryopreservation is another conservation technique that is usually described as the most reliable tool for long-term storage of plant germplasm and reported to be advantageous over most other conservation methods in terms of simplicity, applicability to a wide range of genotypes and ability to maintain the genetic stability of plant material. Thanks to the use of cryopreservation techniques, such as, encapsulation-dehydration, vitrification, encapsulation-vitrification, and droplet-vitrification, many medicinal plant species are conserved indefinitely for the next generations. [ABSTRACT FROM AUTHOR]