Influence of low temperatures on the growth and viability of pure strains of Frankia isolated from Alder nodules

Influence of low temperatures on the growth and survival of Frankia strains were studied. Even when isolated from cold areas, the strains were unable to grow below 15°C. However, the strains remained viable at the low temperatures and were able to give colonies as soon as the growth temperature raised up to 28°C during a few hours.