Why this Assignment?

In ‘Vigyan Ashram’s ‘ microbiology lab, Tricoderma viridae is multiplied, made powder of it, packed and sold to the Farmers & also used by the agriculture department students within the Vigyan Ashram. Tricoderma is an very effective bio control agent for the crops. Hence it is in demand among Farmers, Gardeners and all people involved in agricultural Section.

  1. In order to produce Tricoderma Powder, first we have to inoculate Tricoderma on the sterile substrate, allow it to multiply on it. For inoculation we require pure Tricoderma viridae strain.
  2. When we plated the Tricoderma powder which was made in Ashram on PDA; it was observed that along with Greenish growth of Tricoderma viridae, some unwanted growth (unknown) was observed. So the need was raised to isolate pure form of Tricoderma viridae from the powder.


  1. To isolate Tricoderma viridae from the given powder sample by Streak plate method.
  2. To learn and improve the plating skills.


Stage 1:

Plating of Tricoderma powder (produced in Vigyan Ashram) was done on sterile PDA plate using spread plate technique.

Making PDA Plates
Spreadplates of Tricoderma powder after 10 days of Incubation


Along with Tricoderma , some unwanted whitish growth was observed on the PDA plate.

Stage 2:

  1. The Greenish coloured growth of Tricoderma was seen on the PDA plate. This Tricoderma was Streaked on the sterile PDA plate with the help of Nichrome wire loop. Streaking was done on PDA plate by ‘four quadrant Method’.
  2. The plates were incubated at 36 Degree Celsius in the incubator for 10 days get fully grown Tricoderma.
Four Quadrant Method

Streaking of Tricoderma viridae on Sterile PDA Plate

Observation Of Plates:

Tricoderma viridae streak plates after 2 days of incubation
Plates after 10 days of incubation

The Plates showed Growth of Tricoderma viridae without any contamination. These plates can be further used as an inoculum for multiplication of the Tricoderma on the substrate in order to make Tricoderma powder.