Control of Shoot Tip Necrosis in Shoot Cultures of Portulaca grandiflora Hook

Archana Srivastava,Aruna G Joshi

doi:10.15835/nsb519009

Abstract

Portulaca grandiflora, an important medicinal plant was found to show the incidence of shoot tip necrosis (STN) in shoot cultures obtained from nodal explants in Murashige and Skoog (MS) medium with 3% sucrose along with 8 µM Kinetin and 4 µM BAP. This physiological disorder is primarily due to the deficiency of calcium and boron content in the medium. Thus in the present work varying concentration of boron which was used in the form of boric acid (0.1-0.4 mM), calcium gluconate (3-30 mM) and calcium chloride (3-30 mM) were incorporated in MS medium and its effect on STN was evaluated. The observations revealed that 18 mM calcium chloride was the optimum concentration for lowering STN in shoot cultures to 40% after four weeks.

Highlights

Herbal medicines are most prevalently used by the people of developing countries for their primary health care needs and last decade has seen a considerable rise in pharmaceutical industries where plant extract is most abundantly employed
Regeneration of this plant was done with nodal explants (Srivastava and Joshi, 2009) and it was observed that the shoot cultures were affected with shoot tip necrosis after two weeks which lead to considerable loss of culture
During the regeneration studies of P. grandiflora through nodal explants it was observed that after one week there was browning of the shoot tips followed by necrosis in a basipetalous manner

Summary

Introduction

Herbal medicines are most prevalently used by the people of developing countries for their primary health care needs and last decade has seen a considerable rise in pharmaceutical industries where plant extract is most abundantly employed. Portulaca grandiflora (Portulacaceae) is a succulent ornamental herb associated with a number of medicinal properties It is used for the cure of sore throat, skin rashes, putative immunostimulant (Chavalittumrong, 2007) contains betalain which is an antioxidant (Zryd, 1995), and the plant is antimutagenic (Liu, 1990). It has an efficacy on hepatitis B surface antigen (Zheng and Zhang, 1990), aerial parts are reported to contain various diterpenoids like portulal, portulenone, portulenol, portulene (Ohasaki et al, 1986) and portulene acetal a minor diterpenoid (Ohasaki et al, 1997). Regeneration of this plant was done with nodal explants (Srivastava and Joshi, 2009) and it was observed that the shoot cultures were affected with shoot tip necrosis after two weeks which lead to considerable loss of culture

Methods

Results

Conclusion