GS-2: Government policies and interventions for development in various sectors and issues arising out of their design and implementation
Monoculture in Punjab
Context: Amidst the ongoing farmers’ protests are also questions that are being raised on the sustainability of paddy-wheat cultivation, especially in Punjab.
What is the extent of paddy-wheat monoculture in Punjab?
Punjab’s gross cropped area in 2018-19 was estimated at 78.30 lakh hectares (lh).
Out of that, 35.20 lh was sown under wheat and another 31.03 lh under paddy, adding up to 84.6% of the total area planted to all crops.
That ratio was just over 32% in 1960-61 and 47.4% in 1970-71.
This has been at the expense of pulses (after 1960-61), maize, bajra and oilseeds (after 1970-71) and cotton (after 1990-91)
Wheat replaced chana, masur, mustard and sunflower, while cotton, maize, groundnut and sugarcane area got diverted to paddy.
The only crops that have registered some acreage expansions are vegetables (especially potato and pea) and fruits (kinnow), but they hardly amount to any diversification
Why is monoculture such a problem?
Growing the same crops year after year on the same land increases vulnerability to pest and disease attacks.
The more the crop and genetic diversity, the more difficult it is for insects and pathogens to infect.
Wheat and paddy cannot also, unlike pulses and legumes, fix nitrogen from the atmosphere.
Their continuous cultivation without any crop rotation, then, leads to depletion of soil nutrients. As a result, crops will have to increasingly depend on chemical fertilisers and pesticides.
In Punjab’s case, the issue isn’t as much with wheat, which is naturally adapted to its soil and agro-climatic conditions.
Wheat is a cool season crop that can be grown only in regions – particularly north of the Vindhyas – where day temperatures are within early 30oC range through March (temperature sensitive)
Its cultivation in Punjab is also desirable from a national food security standpoint.
Punjab’s wheat yields – at 5 tonnes-plus per hectare, as against the national average of 3.4-3.5 tonnes – are far too high to make any reduction in its cultivation area.
So, it is basically paddy that needs fixing?
Yes, there are two reasons for it.
The first has to do with paddy being awarm season crop not very sensitive to high temperature stress. It can be grown in much of eastern, central and southern India, where water is sufficiently available.
Punjab contributed 10.88 mt of rice (milled paddy) out of total Central pool procurement of 52 mt in 2019-20. Probably half of this rice of Punjab can, instead, be procured from eastern Uttar Pradesh, Bihar, West Bengal or Assam.
The second has to do with water usage. Farmers usually irrigate wheat five times. In paddy, 30 irrigations or more are given.
Punjab’s groundwater table has been declining by 0.5 m/annum on an average – largely due to paddy cultivation and the state’s policy of supplying free power for irrigation.
This has encouraged farmers to grow long-duration (160 days) water-guzzling paddy varieties like Pusa-44.
Long duration meant that nursery-raising happened in April last week and transplanting by mid-May. But being peak summer time, it also translated into very high water requirement.
Crops were then harvested from October leaving ample time for planting of the next wheat crop (by mid-November).
Before Pusa-44’s release in 1993, Punjab farmers were mostly cultivating PR-106, which required less water and was short duration(145 days).
Has the Punjab government done anything to address this?
The one significant step that it took was enacting the Punjab Preservation of Subsoil Water Act in 2009, that prohibited any nursery-sowing and transplanting of paddy before May 15 and June 15, respectively.
Therefore, transplanting of Pusa-44 was permitted only after the monsoon rains arrived in mid-June. This was done to address the water requirements.
As a result, harvesting was pushed to October-end, leaving a narrow time window for sowing wheat before the November 15 deadline.
Farmers, then, had no option other than burning the paddy stubble left behind after harvesting.
Simply put, groundwater conservation in Punjab ended up causing air pollution in Delhi.
Has there been any way to avoid this trade-off?
One thing that scientists at the Punjab Agriculture University (PAU), Ludhiana have done is breed shorter-duration paddy varieties. These take between 13 and 37 days less time to mature than Pusa-44, while yielding almost the same (see table 2).
PR-126, a variety released in 2017, has a mere 123 days duration (inclusive of 30 days post nursery-raising) and its yield is 30 quintals per acre.
In 2012, 39% of Punjab’s non-basmati paddy area was under Pusa-44. That was down to 20% in 2021, while the share of shorter-duration varieties, mainly PR-121 and PR-126, has crossed 71%.
While Pusa-44 requires around 31 irrigations, it is only 23 in PR-126 and 26 in PR-121. There would be further 3-4 irrigation savings if farmers adopt direct seeding of paddy, as opposed to transplanting in flooded fields.
A single irrigation consumes roughly 2 lakh litres of water per acre.
Way forward
A sensible strategy could be to limit Punjab’s paddy area and ensure planting of only shorter-duration varieties.
Further water savings can be induced through metering of electricity and direct seeding of paddy.
