T. Pullaiah

Micropropagation of Three Varieties of Caralluma adscendens via Nodal Explants

A procedure for in vitro propagation of pharmaceutically valuable varieties of Caralluma adscendens from nodal explant, is described. The highest shoot multiplication with 80% frequency was achieved within one month on Murashige and Skoog’s medium supplemented with 8.87 μM BA. Shoot multiplication occurred in subsequent subcultures in culture bottles on MS medium. Regenerated shoots were rooted on half strength MS medium supplemented with NAA (0.54 μM) in all the three varieties. The rooted plants were hardened for establishment in soil.

In vitro shoot multiplication and conservation of Caralluma bhupenderiana Sarkaria - an endangered medicinal plant from South India

An efficient protocol was described for the rapid in vitro multiplication of an endangered medicinal plant, Caralluma bhupenderiana Sarkaria, via enhanced axillary bud proliferation from nodal explants collected from young shoots of six-months-old plant. The physiological effects of growth regulators [6- Benzyladenine (BA), kinetin (Kn), 2-Isopentyl adenine (2iP), zeatin (Zn), indole-3-acetic acid (IAA), indole-3-butyric acid (IBA)], different strengths of Murashige and Skoog (MS) medium and various pH levels on in vitro morphogenesis were investigated. The highest number (8.40 + 0.50) of shoots and the maximum average shoot length (3.2 ± 0.31 cm) were recorded on MS medium supplemented with BA (8.87 μM) at pH 5.8. Rooting was best achieved on half-strength MS medium augmented with NAA (2.69 μM). The plantlets regenerated in vitro with well-developed shoot and roots were successfully established in pots containing peat mass and garden manure in 1:1 ratio and grown in a greenhouse with 80% survival rate. The regenerated plants did not show any immediate detectable phenotypic variation. Key words: Apocynaceae, asclepiadoideae, conservation, micro-propagation, endangered, Caralluma bhupenderiana.

Phytosynthesis of eco-friendly silver nanoparticles and biological applications –A novel concept in nanobiotechnology

Nano-biotechnology is an undoubtedly future generation technology which offers potential applications in multidisciplinary areas of science and technology. In the present day’s production, stabilization and utilization of nanoparticles is the eliminatory division in modern science receiving immense attention of scientists engaged in different fields of research. A number of metal nanoparticles have been engineered so far; however among these, silver nanoparticles gain more attention because of their unique applications in distinctive fields of biology. This review presents an overview on phytosynthesis of silver nanoparticles; role of phytochemical constituents in reduction of silver nanoparticles, factors responsible for the synthesis of silver nanoparticles and their crucial role in control of size and shape etc. The biological applications of phyto-synthesized silver nanoparticles are given in brief which will direct a path for further biological studies in future to make the study more useful for human welfare and benefits. Key words: Phytosynthesis, silver nanoparticles, phytochemicals, biological activities

Callus Culture and Plant Regeneration from Seedling Explants of Pergularia daemia (Forsk) Chiov

Callus cultures were established from seedling explants of Pergularia daemia (Forsk) Chiov on Murashige and Skoog (MS) medium supplemented with different concentrations of auxins. Optimal callus developed from leaf explants on MS medium supplemented with 2,4-D (2 mg l−1) + 2iP (0.1 mg l−1), was used for morphogenesis. Adventitious shoots were regenerated (70%) from the calli on MS medium supplemented with NAA (0.1 mg l−1)+ BAP (2 mg l−1). Individual shoots were rooted on half strength MS medium supplemented with 0.1 mg l−1 IBA. Plantlets with well developed roots were successfully transferred to soil and 50% of the transferred plants survived.

Brachystelma nigidianum (Apocynaceae: Asclepiadoideae), a new species from India

SummaryBrachystelma nigidianum (Apocynaceae: Asclepiadoideae), a new species from the Nigidi forest near Kadiri, Anantapuramu district of Andhra Pradesh State, India is described and illustrated. It is similar to B. beddomei Hook. f. and B. volubile Hook. f., in its climbing habit and leaf shape, but can be distinguished from these two species by the length of its calyx (9 – 10 mm long), distinct urceolate-shaped corolla tube, reddish maroon corona and apically connate follicles.

Embryological investigations inCentipeda minima (Asteraceae)

Anthers are tetrasporangiate. Anther tapetum is of the periplasmodial type and its cells become polyploid. Microspore tetrads are tetrahedral. Pollen grains are shed at 3-celled stage. Ovule is anatropous, unitegmic and tenuinucellate. Embryo sac development is of the Polygonum type. Antipodals are either 2 or 3 in number. They become polyploid and are persistent. Synergids are hooked. Endosperm development is of the cellular type and embryo development conforms to the Grand period I, Megarchetype II, series A and sub series A2 in the first embryonic group and it keys out to the Calendula subtype.

A contribution to the embryology ofCicerbita alpina (Linn.) Wallr.

Development and structure of male and female gametophytes and fertilisation ofCicerbita alpina (Linn.) Wallr. have been studied.