Role of PGPR and heavy metals in Germination and growth of Andrographis paniculata (Kalmegh)

Abstract

Andrographis paniculata is a shrub herbal remedy well-known as echinacea or Kalmegh. The present work was carried out to study the role of PGPR and heavy metals in germination and growth of A. paniculata. It was found that most of isolates significantly increased growth parameters such as plant height and root length and seed germination was also increased when seeds were pre-treated with PGPR isolates. All these isolates were tested for their tolerance towards different heavy metals. Majority of the bacterial isolates were found tolerant to Cd (100), Ni (200), Zn (100), Co (200), Cu (100), Cr (200), Pb (200) and Hg (100) µg/ml respectively. The isolates, tolerant to cadmium were further tested for PGPR traits such as IAA production, Ammonia Production, catalase, HCN production, PO-4 solublization and seed germination test. Fifty potential PGPR were isolated from rhizosphere of Kalmegh. They were found to promote seed germination and plant growth.