ORIGINAL ARTICLES  BIOENCAPSULATION IN BIOTECHNOLOGY 

Minerva Biotecnologica 2007 June;19(2):51-5

Copyright © 2007 EDIZIONI MINERVA MEDICA

lingua: Inglese

An improved technique for preparation of gel-entrapped fungal spores

Vassilev N. ¹, Nikolaeva I. ², Vassileva M. ¹

¹ Department of Chemical Engineering University of Granada, Granada, Spain 2 Department of Public Technology, Malardalen University, Vasteras, Sweden

Aim. One of the challenges in the field of arbuscular mycorrhizal fungi (AM) is their cultivation in the absence of host roots and preparation of AM-inoculants free of contaminants. The use of Ri T-DNA transformed roots has permitted increased AM spore production which was further improved by using two-compartment Petri dishes.
Methods. In this work, we proved possible development of Glomus intraradices in liquid media which included locust bean gum (LBG) and k-carrageenan. G. intraradices formed about 1700-2400 spores in 12 weeks. Entrapment of the AM spores was carried out directly thus avoiding the laborious “conventional” technique for spore entrapment.
Results. In this work we produced beads containing k-carrageenan/AM mycelium, LBG/AM mycelium+k-carrageenan free of AM, and LBG/AM mycelium+k-carrageenan/AM mycelium where the spore number per bead ranged from 1 to 7, 3 to 11, and 4 to 10, respectively. Further introduction of gel-bead-AM formulations into soil-plant system demonstrated their efficiency. Particularly combinations between LBG and k-carrageenan resulted in higher level of mycorrhization, increased plant growth and phosphate acquisition compared with non-inoculated control and treatments that received free AM inoculum.
Conclusion. This technique could be further improved by using other gel materials, AM fungi and/or plant growth promoting microorganisms such as nitrogen-fixing and phosphate-solubilizing microorganisms.