Seasonal Population Dynamics of Rhizosphere and Non-rhizosphere Soil Microorganisms of Chir Pine Seedlings (Pinus roxburghii Sarg.)

Abstract

Seasonal population dynamics of bacteria, actinomycetes and fungi was studied in rhizosphere and non-rhizosphere soil of chir pine (Pinus roxburghii Sarg.) seedlings growing in polybags and in situ (forest). In greenhouse experiment bacteria and actinomycetes were present in higher numbers and their populations fluctuated with season. Fungal population, although lower in numbers, remained stable throughout the year. Population fluctuations with lower numbers were more prominent in rhizosphere and non-rhizosphere soils of forest plants. Differential bacterial population characteristics viz. sporeformers, fluorescent colony producers, methylene blue reducers, ammonifiers and glucose fermenters were also taken into account. The population of sporeformers was comparable with methylene blue reducers, which was higher than fluorescent colony producers, ammonifiers and glucose fermenters, respectively. The rhizosphere soil bacterial count of nursery seedlings ranged from 4.36 x 10