Shahina Parveen

TDZ-induced high frequency shoot regeneration in Cassia sophera Linn. via cotyledonary node explants.

Cassia sophera Linn. is an important medicinal plant belonging to family Fabaceae. It is extensively used in Homeopathy and is well known for its medicinal properties. The present study describes a simple, efficient and reproducible regeneration system for in vitro propagation of C. sophera through cotyledonary node (CN) explant excised from 21 d old axenic seedlings. Explants were cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ). Multiple shoots were produced on all the concentrations of TDZ; however 2.5 μM concentration proved to be optimal for the production of maximum number of shoots. To avoid adverse effects of prolonged exposure to TDZ in long term establishment, the cultures were transferred to TDZ free MS medium fortified with various concentrations of 6- benzyl aminopurine (BA) for multiplication, proliferation and elongation of induced shoots. Emergence of new shoot buds and multiplication continued up to second subculture passage and maximum number (14.9 ± 1.4) of shoots obtained on MS + BA (1.0 μM). Best rooting response was observed on half strength MS containing Indole-3-butyric acid (IBA) (1.0 μM). Regenerated plantlets were successfully acclimatized and hardened off inside the culture room and then transferred to green house with 100 % survival rate.

Development of a regeneration system via nodal segment culture in Veronica anagallis-aquatica L. – an amphibious medicinal plant

Abstract The present study describes an effective, reproducible and rapid regeneration protocol for in vitro shoot development of the medicinally important, semi-aquatic plant Veronica anagallis-aquatica L. through mature nodal segments on Murashige and Skoog (MS) medium. The most effective medium for shoot regeneration was MS medium fortified with 0.5 µM 6-benzyladenine (BA), on which the maximum number (43.7±1.85) of shoots per explant having a shoot length of 5.0±0.25 cm were produced. The addition of auxins along with optimal concentration (0.5 µM) of BA did not further improve the regeneration capacity of the explants; instead, it resulted in an adverse effect. Nodal segments cultured in MS liquid medium without agar provided a better and early response for efficient shoot regeneration, and simultaneous rooting as compared to solidified medium. The optimal liquid medium comprised of MS+BA (0.5 µM) on which a maximum 20.7±1.76 shoots per explant were produced and grew healthier. Both half strength MS and MS basal medium supplemented with α-naphthaleneacetic acid (NAA) responded equally for root induction. Rooted shoots were successfully transferred to field conditions with 80% survival. Histological studies revealed the de novo origin of shoots which would make this protocol suitable for transformation techniques.

Factors affecting in vitro plant regeneration from cotyledonary node explant of Senna sophera (L.) Roxb. - A highly medicinal legume

An efficient in vitro regeneration protocol has been developed for a medicinal legume Senna sophera (L.) Roxb. using Cotyledonary Node (CN) explants. The plant exhibits high medicinal potential and is being used in several traditional and homeopathy system of medicine. The present study described an in vitro regeneration protocol, where different factors were optimized for maximum multiplication and propagation. The age of the explant, plant growth regulators, basal medium, pH of the medium and sucrose concentrations markedly influenced in vitro propagation of S. sophera. Among 14, 21 and 28 day-old CN explants, 21 day-old explants were found to be the most responsive. A maximum of 19.50 ± 0.51 shoots/explant were produced from 21 day-old seedling explants, having an average shoot length of 5.23 ± 0.14 cm in 86.00 ± 2.08% cultures after 6 weeks of incubation on Murashige and Skoog (MS) medium supplemented with benzyl adenine (BA) (5.0 μM) + naphthalene acetic acid (NAA) (1.0 μM) and containing 3% sucrose with pH value adjusted at 5.8. The highest rooting frequency (96.00 ± 2.08%) with maximum of 7.63 ± 0.23 roots/shoot having an average root length of 4.86 ± 0.35 cm was obtained on half-strength MS medium with 1.0 μM indole-3-butyric acid (IBA) and solidified with 0.25% phytagel. The plantlets were acclimatized in sterile soilrite under controlled conditions, hardened and successfully transferred to soil in natural conditions with 90% survival rate. The regenerated plants showed no morphological variations in terms of leaf shape, flower shape, pod size, number of seeds etc., when compared with the naturally grown plants in the field. Keywords: Senna sophera , fabaceae, cotyledonary node, in vitro shoot regeneration, rooting, acclimatization African Journal of Biotechnology , Vol. 13(3), pp. 413-422, 15 January, 2014

Historical Perspective and Basic Principles of Plant Tissue Culture

In 1902 Gottlieb Haberlandt proposed the idea to culture individual plant cells on artificial nutrient medium. Although he failed to culture them due to poor choice of experimental materials and inadequate nutrient supply, he made several valuable predictions about the nutrients’ requirement for in vitro culture conditions, which could possibly induce cell division, proliferation and embryo induction. Tissue culture has now become a well-established technique for culturing and studying the physiological behaviour of isolated plant organs, tissues, cells, protoplasts and even cell organelles under precisely controlled physical and chemical conditions. Micropropagation is one of the most important applications of plant tissue culture. It provides numerous advantages over conventional propagation like mass production of true-to-type and disease-free plants of elite species in highly speedy manner irrespective of the season requiring smaller space and tissue source. Therefore, it provides a reliable technique for in vitro conservation of various rare, endangered and threatened germplasm. Micropropagation protocols have been standardized for commercial production of many important medicinal and horticultural crops. Somatic embryogenesis is an extremely important aspect of plant tissue culture, occurring in vitro either indirectly from callus, suspension or protoplast culture or directly from the cell(s) of an organized structure. Advantages of somatic embryogenesis over organogenesis include several practical means of micropropagation. It reduces the necessity of timely and costly manipulations of individual explants as compared to organogenesis.

Plant Tissue Culture: Applications in Plant Improvement and Conservation

Plant tissue culture is a significant contribution in micropropagation of ornamental and forest trees, production of pharmaceutically interesting compounds and plant breeding for improved nutritional value of staple crop plants as well as in the improvement of tree species. Plant tissue culture can provide high-quality planting material for the fruits, vegetables and ornamental plants and forest tree species throughout the year, irrespective of season and weather, thus opening new opportunities to producers, farmers and nursery owners. The biotechnological approaches like haploid induction, somaclonal variation, etc. to improve traits are also its important applications. Plant tissue culture is a noble approach to be used in bioproduction, bioconversion or biotransformation of the valuable secondary products for large-scale production and biosynthetic studies.

Application of Molecular Markers in Medicinal Climbers

Nowadays, medicines derived from plants have attained worldwide popularity because they have no or very negligible side effects. Therefore, the demand of medicinal plants by rapidly growing pharmaceutical industries has increased tremendously during the past few decades. In India, majority of the population depends upon traditional systems of medicine, i.e. homeopathy, Ayurveda and Unani which utilise the whole plants or plant-derived materials for the treatment of various diseases and medicinal preparations. However, due to indiscriminate collection of medicinal plants from their wild/natural habitats and other anthropogenic activities, this medicinal wealth is being lost at an alarming rate, and as a consequence of this, many valuable plants are threatened to extinction. So, it is very vital to take necessary steps for their proper authentication, conservation, germplasm cataloguing and devising conservation policies. For this purpose, molecular markers have played a significant role as they provide information ranging from diversity at nucleotide level to gene and allele frequencies, the extent and distribution of genetic diversity and population structure. During the past few decades, molecular markers have revolutionised the meaning of conservation genetics which has emerged from a theory-based field of population biology to a full-fledged pragmatic discipline. Therefore, in this chapter, we have explored the utilisation of various molecular markers for the genetic studies specifically in medicinal climbers.

Molecular Markers and Their Application in Plant Biotechnology

During the past few decades, the significant progresses have been made with the development of molecular marker for the detection and exploitation of DNA polymorphism in the field of plant biotechnology and their genetic studies. According to the type of study to be conducted, one can choose a specific marker from a variety of different markers, viz. morphological, biochemical and DNA-based molecular markers. The molecular markers are of two types as hybridisation-based or non-PCR-based markers. These DNA markers offer several advantages over traditional phenotypic markers, as they provide data that can be analysed accurately. This chapter provides a detailed account of utilisation of different molecular markers to study the polymorphism if any among the natural populations as well as in regenerants obtained through clonal propagation.

In Vitro Conservation Protocols for Some Commercially Important Medicinal Plants

Interest and support for the conservation and development of medicinal plants is increasing in all parts of the world. This is due, in part, to a growing recognition given to the role of medicinal plants in the provision of culturally relevant and affordable health care in creating sustainable livelihoods and in the vital conservation of biodiversity. This has also drawn the attention of the world community towards the need for creating mechanisms to ensure sustained development of the sector and to allow sharing of information between countries, organizations and agencies. The value of medicinal plants to human livelihoods is essentially infinite. The special significance of medicinal plants in conservation stems from the major cultural, livelihood or economic roles that they play in many people’s lives. Many of the threats to medicinal plant species are similar to those causing endangerment to plant diversity generally. The most serious proximate threats generally are habitat loss, habitat degradation and over-harvesting. In order to protect such endangered species from possible extinction, the exploitation of medicinal plants must be accompanied by conservation measures. Application of tissue culture of plant cells, tissues and organs is the most promising tool for medicinal plant conservation.