Decomposer Technology for Stubble

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The Union Government has said that it will this year test a straw-decomposing technology developed by scientists at the Indian Agricultural Research Institute, Pusa, to deter farmers from burning paddy stubble.

Features of PUSA Decomposer

It is essentially a fungi-based liquid solution that can soften hard stubble to the extent that it can be easily mixed with soil in the field to act as compost.
This would then rule out the need to burn the stubble, and also help in retaining the essential microbes and nutrients in soil that are otherwise damaged when the residue is burned.
The window of time required for the solution to work, which is currently the main concern of farmers, is around 20 to 25 days, as per the IARI.
Farmers argue that this window is too long for them, as they ideally wait about a week or 10 days after harvesting the non-basmati variety of rice, which leaves hard stubble, to sow the wheat crop.
The IARI scientists have said that farmers do not necessarily have to wait for the entire 20-25 day window before getting to work on the field. They can start ploughing and preparing the land 10-15 days after spraying the decomposer.
There are seven strains of fungi that IARI has identified after research which help in rapid breakdown of hard stubble.
These seven strains of fungi are packed into four capsules, which cost about Rs 20 per pack of four. But there is a process for developing the liquid solution from these capsules which can take about four to five days.
It starts with boiling 25 litres of water mixed with 150 grams of jaggery, which scientists say has properties that help in multiplication of fungi. After this mix has cooled, 50 grams of besan (or gram flour) is added to it along with four ‘Pusa Decomposer’ capsules.
This solution is then covered with a thin piece of cloth and left in a dark room for four days. On the fourth day, a thick growth of fungi will be seen on top of the solution. This has to be mixed well, and thereafter the solution is ready for use.
A 25-litre solution is advisable for use in one hectare of land after being mixed with 500 litres of water. It can be sprayed over the field and left to do its work.
The technology would be used over 100 hectares of land in Punjab and Haryana, 800 hectares in Delhi and 10,000 hectares in Uttar Pradesh.