Unwanted ecological complications
Though the Green Revolution rice technologies have ensured the food security of 1.4 billion Indians, it proved ecologically disastrous with increased consumption of pesticides, herbicides and groundwater;
Before the Green Revolution, North West India did not grow much rice due to its semi-arid and arid climate. But rice cultivation has grown phenomenally from 0.5 million hectares (ha) in 1966 to more than 5 million ha in 2010 onwards with the introduction of Green Revolution Technology; dwarf high-yielding varieties supported by higher uses of chemical fertilizers and irrigation-based Transplanted Rice Systems. Before the Green Revolution, rice like other summer crops was directly seeded and weeding was done manually because its area was small and labour was plentiful. Favourable government policies including assured procurement at minimum support prices (MSP) and subsidized energy and chemical fertilizers also greatly contributed to successful rice cultivation.
Though the Green Revolution rice technologies have ensured the food security of 1.4 billion Indians during the last five decades and made it possible for India to export rice, particularly Basmati rice. However, it proved ecologically disastrous with increased consumption of pesticides, herbicides and groundwater. Nitrates and phosphates from fertilizers have leached into soils. Earth-warming methane gas emissions from the anaerobic (TPR) wetland rice farming system contribute as much as 34 million tons annually with China and India making up 50 per cent of total GHG emissions.
The water-guzzling TPR system has depleted the groundwater to alarming grey zone levels in major parts of NW India. Further, over 30 million tonnes of paddy stubbles burning annually is making NW India, particularly the NCR region as the gas chamber on the onset of the winter from October 25-November 15 by causing serious health hazards to the human population.
Impractical response
Ecological complications of the water-guzzling TPR system have depleted the groundwater to alarming grey zone levels in major parts of the region and causing air pollution annually which leads to the prophecy by national policymakers to shift rice cultivation to the eastern zone without providing any viable alternate cropping systems to the farmers. The government of Punjab-Haryana promulgated the 'Preservation of subsoil water Act-2009' by banning the transplantation of paddy before June 15 for the conservation of groundwater. Haryana government has also promoted a technically impractical crop diversification scheme 'Mera Pani- Meri Virasat' to replace paddy with maize and other crops including ridiculous 'Kept paddy fields uncultivated' with the huge financial assistance of Rs 17500/ha.
Further, to control the air pollution due to stubbles burning, the government without considering the practical problems of the farmers of brief getaway periods for paddy stubbles management is regularly suggesting impractical solutions such as
On-farm digestion of paddy stubbles into organic fertilizers by the spraying of unworthy Pusa decomposer;
Use of paddy stubbles for ethanol & electricity generation;
Promoting the farmers to purchase machinery for the collection of paddy stubbles without providing its economically beneficial disposal;
Imposing fines on the farmers for paddy stubble burning without providing Eco and Farmer friendly practical alternate solutions etc which proved futile and unfriendly to the farmers, who are now being regularly harassed by corrupt officials in the name of air pollution.
Solution to ecological complications
Interestingly, fewer incidences of paddy stubbles burning were reported annually before October 10 despite about 40 per cent paddy harvesting which explained that 'Farmers compelled to adopt the ecologically disastrous practices of paddy stubbles burning only due to brief getaway periods of 10-15 days between paddy harvesting and sowing next crop wheat, mustards etc. Thus, on-farm paddy stubbles burnings can easily be minimised by increasing the getaway periods between paddy harvesting and sowing the next rabi crop by promoting the early maturity rice varieties such as PB-1509, PR-126 etc which mature in 120-125 days and are harvested by end of September. Then, the farmers can also take the additional crop Sesbania (Dencha) for green manure or short-duration vegetable crop by turning paddy stubbles into the soils as already done by some farmers from NCR. Then even if some on-farm paddy stubble burning happened during September, it will not prove to be a serious health hazard due to favourable climatic factors; warmer temperatures, high wind speed and rains caused by the late withdrawal of the monsoon cycle.
Further, the shifting from Transplanted Rice (TPR) to Direct Seeded Rice (DSR) will save about 40 per cent of groundwater irrigation and cost of cultivation and also reduce releases of GHGs without any losses of seed yield. It will further increase the getaway periods for on-farm operations for the management of paddy stubbles because in DSR all rice varieties mature about 10-15 days earlier than the ecologically disastrous transplanted rice. A new farmers-friendly paddy cropping calendar for DSR (Tar Vattar Direct Seeded Rice) was developed by my research team during 2015-2022 with recommendations of advanced date of sowing (DOS) to May 20 onwards (during hot and dry summer season) instead of faulty DOS as 15 June onwards recommended earlier by ICAR and SAUs.
Then, the sowing of paddy crops recommended in 'Tar Vattar' (good moisture) fields prepared after pre-sown irrigation and followed by an immediate spray of pre-emergence weed killer Pendimethalin etc and delay first irrigation at 2-3 weeks after the sowing and subsequent irrigations by adopting AWD cycle (Alternate Wetting-Drying Cycle) of 7-10 days based on rains which make rice crop nearly weed free and competitive against any brief drought period caused by failure of rains.
Lucrative technology for farmers
The new Tar Vattar DSR cropping calendar with sowing from May 20 onwards has been adopted by the Govt of Haryana and Punjab during crop season 2022 and thousands of farmers in over three lakhs ha areas harvested it with on an average 6-7 t/ha despite dwarfism virus diseases and heavy unseasonal rains at the time of maturity. Farmers, even those from arid and semi-arid zones of Northwest and Central India have successfully adopted TAR VATTAR DSR technology due to its ecologically and farmer-friendly packages of practices that greatly reduced water requirements comparable with other summer food grains, oilseeds and pulses crops. The incidence of pests and diseases is also less. Another crucially important advantage of using DSR is that it enhances groundwater recharge through the rain. The conventional tillage used in TPR forms a plough pan in the soil which has less porosity that causes lateral water run-off and soil erosion during rainfall. Soils under the minimum tillage system in DSR, on the other hand, provide good avenues for groundwater recharge.
Therefore, to control the ecological complications of paddy cultivation (air pollution & groundwater conservation), the government should
Promote the New Tar Vattar DSR cropping calendar with sowing dates from May 20 with early maturing rice varieties which can be harvested by September;
Ban sale and sowing of long-duration (130 days maturity or more) rice varieties in NW India;
Reschedule government purchases of paddy on MSP from September 10 to October 10 in NW-India;
Long-duration Basmati rice varieties cultivation only under contract farming with legal responsibility for disposal of paddy stubbles by the contracting rice millers/ company.
The writer is a Former Principal Scientist at ICAR-IARI, New Delhi Views expressed are personal