Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
with red worms, this includes composting with bacteria, fungi, insects, and other bugs.
Different Phases of Aerobic Composting
Most commonly used aerobic composting process involves three different phases. First
Mesophilic phase with moderate temperature, lasts for a few days, second Thermophilic phase
with high temperature, lasts from a few days to several weeks and final Curing and maturation
phase with moderate to ambient temperature, lasts 1-2 months (Fig. 1). This whole process of
composting is carried out by involvement of different microbes. The initial process is carried out by
mesophilic microorganisms followed by the decomposition of raw material by the involvement of
thermophilic microorganisms. These include fungi, bacteria and actinomycetes (Hultman, et al.,
2010; Partanen et al., 2010). Once the readily degradable materials are degraded, the reaction
rate slows down. Eventually the temperature decreases once again to the mesophilic range
through heat loss from the surface of the heap and again the mesophiles, either through reinvasion
from outside or through germination of heat resistant spores, dominate.
Figure 1: Composting process and its different phases
Compost Microbiology
Bacteria, fungi and actinomycetes are the three major groups of microorganisms largely
responsible for most of composting process. Bacteria are the smallest living organisms and
the most numerous in compost; they make up 80 to 90% of the billions of microorganisms typically
found in a gram of compost. Bacteria are responsible for most of the decomposition and heat
associated with composting. Bacteria don't have to be added to the compost. They are present
virtually everywhere, and enter the pile on every single bit of organic matter. Many types of
bacteria participate in the composting process, thriving at different temperatures and on different
materials. Mesophilic bacteria break down soluble, readily degradable compounds (sugars,
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