A win-win alternative

Central Ground Water Board’s recent report predicted a grim scenario in the Punjab-Haryana region, resulting from over-exploitation of subsoil water, wherein the water level is depleting at an alarming rate of 50 cm per year. The state agriculture department further pointed out that of the total groundwater extracted, 96.65 per cent is being used for agriculture in the rice-growing areas. Considering these facts, Punjab and Haryana have already banned the transplantation of paddy crops before June 15 under the 'Preservation of Subsoil Water Act, 2009'. FAO’s manual 'Crop Water Needs' highlights that the biological need of the rice crop for water is only 500-700 mm for the overall growing season (150 days). However, the farmers are applying 1,500-2,000 mm water due to flawed agronomic practices of water-guzzling. Transplanted rice (TPR) was imported from IRRI-Manila by the national policymakers during the 'Green Revolution', and introduced in Punjab-Haryana which, otherwise, were cultivating rice for ages through sustainable agronomic practices of direct seeding — just like other crops including wheat, sorghum, gram, mustard, moong etc. Favourable government policies (MSP, subsidised energy & chemical fertilisers) further contributed to the success story of transplanted rice cultivation, which ensured the food security of India during the last five decades, and also ensured Rs 70,000-crore export in 2022. However, the water-intensive transplanted rice has depleted the groundwater to an alarming grey zone level in major parts of the region. This led to the envisioning of a shift of rice cultivation to eastern India by policymakers over the last two decades, which, however, has not been adopted by the farmers.

Globally, almost all the crops are cultivated through direct planting of seeds to the fields prepared after the irrigation and having sufficient moisture for proper germination of the seeds. The transplanted rice process is practiced only in the flooded fields of high-rain zones (over 1000 mm) of Southeast Asia for the purpose of easy weed control. But surprisingly, Indian policymakers introduced water-guzzling transplanted rice system to the semi-arid zone of NW-India during the 'Green Revolution', which proved to be ecologically disastrous by causing fast depletion of groundwater. Furthermore, against the traditional agronomic practices of direct seeding in the fields having good moisture (TAR-VATTAR), the IRRI, ICAR & SAUs preferred to promote the flawed Dry-DSR (DDSR) technology during 1995-2015 to alleviate the negative impacts of the water-guzzling transplanted rice plantation. Dry-DSR failed due to faulty sowing dates (from June 15 onwards which coincides with the onset of monsoon rains) and flawed sowing method (sowing on the dry bed followed by immediate irrigation and further frequent irrigations at an interval of 3-4 days). Despite the government’s incentives, the farmers have been slow to adopt Dry-DSR due to the excessive weed pressure and frequent application of expansive post-emergence weed-killer chemicals. Many farmers, who tried DDSR, eventually returned to the transplanted rice, imparting serious setback to the water-friendly DSR technology.

Subsequently, DSR was improved to TAR-VATTAR DSR during the 2014-2017 period by our research team at ICAR-IARI Karnal, which was further refined by me in the capacity of farmer's scientist 2017 onwards, after my retirement. The TAR VATTAR DSR means “Sowing of DSR in good moisture fields prepared after pre-sown irrigation”. The sowing date is recommended during the May 20-June 10 period (about a month prior to the onset of the monsoon) at 20-25 kg seed/ha using a DSR seed drill or traditional broadcasting method, along with application of weed-killer Pendimethalin at 5 litres (per 500 litres of water)/ha immediately after the sowing. Then, the first irrigation is delayed by 15-20 days, and subsequent irrigations by 7-10 days by using alternate wetting and drying cycle based on the soil type and rain pattern, which make DSR crops nearly weed-free without the application of post-emergence herbicides. A new cropping calendar for the sowing of TAR-VATTAR DSR, initiating from May 20 onwards, has also been approved by the governments of Punjab & Haryana since 2022. The weed problem, if any, appears due to unseasonal pre-monsoon rains and is managed with post-emergence weed-killers like Bispyribac Sodium, Pyrazosulfuron Ethyl, Sulfonylurea etc.

Direct seeded rice: a great hope

The improved TAR-VATTAR DSR became popular among farmers in the state of Punjab, with its adoption on over 0.6 million ha (approx. 20 per cent of the rice areas) in 2021 during the Covid period due to the shortage of migrant labourers. Then, a press release dated April 1, 2023, by the Hon'ble CM of Haryana, highlighted that “DSR was grown on over 72,000 acres with a saving of 31,500 crore litres water (saving of about 45 lakh litres water per acre)”, which evidently proved the usefulness of this ecology- and farmer-friendly sustainable technology. The DSR technology saves about 40 per cent groundwater irrigation, energy (electricity & diesel) and cost of cultivation without any penalty on seed yield and grain quality, and the incidence of pest diseases is also less. Thus, the DSR provides a viable alternative to water-guzzling transplanted rice, as all the rice varieties in DSR require less water and are harvested 10-15 days earlier, allowing more time for the management of paddy stubble, which causes less stubble burning and, hence, a smaller carbon footprint.

Now, to change the mindset of farmers to shift from water-guzzling TPR to DSR, governments should promote eco-friendly TAR-VATTAR DSR with incentives of Rs 7,000 per acre. They can even legally ban the flawed agronomic practice of water-guzzling transplanted rice by expanding the scope of 'Preservation of Subsoil Water Act, 2009'. Recently, to draw attention to this novel technique, PAU’s Vice Chancellor SS Gosal, while addressing the IRRI-BMGF-PAU-ICAR meet, announced that “the TAR-VATTAR DSR technique is one of the most suitable forms of DSR for Punjab and will enable farmers to maintain their yields and contribute to environmental sustainability.” The impact of DSR technology can be very significant since rice-wheat is the major cropping pattern practiced on over 15 million ha of land in the Indo-Gangetic Plains.

The writer is former Principal Scientist, ICAR-IARI, New Delhi. Views expressed are personal