Viability of ectomycorrhizal fungus mycelium entrapped in calcium alginategel

We studied the viability of fragmented mycelium of Pisolithus tinctorius an d Paxillus involutus entrapped in calcium alginate gel to determine the eff icacy of this method of producing ectomycorrhizal fungus inoculum. Fungi we re grown in MMN solution at 28 degrees C before being fragmented in a blend er and subsequently entrapped in calcium alginate. We tested different rati os of alginate and mycelium suspension to 0.7 M CaCl2. The ratio 8:10 resul ted in well-formed beads of the highest viability for Paxillus involutus (9 9%) and for Pisolithus tinctorius (75%). Paxillus involutus mycelium was mo re than 90% viable when entrapped mycelium was 10 to 50 days old, and Pisol ithus tinctorius attained its highest viability (55%) for 20- to 40-day-old mycelium. Gel entrapped Paxillus involutus mycelium grew well at all tempe ratures after 30 days of storage, but viability significantly decreased aft er 60 days storage at 6 degrees C on dry filter paper. For gel-entrapped Pi solithus tinctorius mycelium, viability was highest when stored at 25 degre es C in 0.7 M CaCl2. Entrapment of Paxillus involutus fragmented mycelium i n calcium alginate beads under the conditions that we propose can be used s uccessfully to produce inoculum.