Scientists at the Indian Institute of Rice Research (IIRR) have developed paddy varieties that require at least 30 per cent lower phosphorous at a time when the country is facing a huge challenge in meeting fertiliser demand.
Tested successfully at the institute’s Rajendranagar trials fields, a small chunk of the seed consignments have already reached the fields of farmers in Telangana and Karnataka.
Displaying the paddy crop that was grown in a healthy way on a small plot with very low phosphorous content for about 25 years at the institute’s trial field in Rajendranagar, Anantha M S, senior scientist (Plant Breeding) at ICAR-IIRR, told businessline that four varieties have been developed by the institute that are showing tolerance to low-phosphorous content in the soil.
Good alternative in East
The institute is now targeting the States where the BPT variety of paddy is grown. It has sent limited consignments of seeds to about 20 farmers in Karnataka’s Ballari, Kushtagi and Raichur districts. “We have distributed the seed to 10 farmers in Telangana and Andhra Pradesh,” Anantha said.
DRR Dhan 60 is the first rice variety in the country with low phosphorous tolerance for any crop. The improved Samba Masuri variety is high-yielding and has resistance to bacterial blight. With a maturity period of 125-130 days, the variety gives a maximum yield of 5.19 tonnes a hectare (with 60 kg/ha of phosphorous). With this potential, the IIRR scientists expect that it can be a good alternative to farmers in Eastern India. It can be grown in other rice-growing States such as Telangana, Andhra Pradesh, Chhattisgarh, Tamil Nadu, Karnataka and Odisha.
DRR Dhan 66, DRR Dhan 65, and WGL-1487 are the other varieties which offer the same benefits. WGL-1487 has been developed in association with the scientists at Prof Jayashankar Telangana State Agricultural University.
“Based on the identified zones for which varieties have been released, these four varieties have the potential to occupy 3-4 million hectares area under rice cultivation,” Satendra Kumar Mangrauthia, Senior Scientist, said. The IRRI team has screened rice genotypes that tolerate low phosphorous conditions to develop the new varieties, he said.
Key macronutrient
Phosphorous is a key macronutrient responsible for the growth and yields of paddy as it plays a crucial role in energy storage and transfer within cells. Besides speeding up root development, it facilitates greater Nitrogen uptake and results in higher grain protein yields.
“An overwhelming majority of soils in the rice-producing areas in India are deficient in phosphorous. Most of the phosphorus applied as fertiliser gets drained into water bodies, forcing farmers to go in for repeated application,” he said.
Costly affair
India depends on imports and offers huge subsidies to make phosphorous-based fertilisers affordable for farmers. The government and farmers are spending huge amounts on fertilisers to replenish the nutrients in the soil. Phosphorous fertilisers are imported. Limited availability of the chemical, too, is a cause of concern.
In 2020-21, the country imported 75 lakh tonnes of phosphatic fertilisers (DAP and NPK), accounting for nearly one-third of total fertiliser imports. In the first half of the current fiscal, the Centre has spent ₹60,939 crore towards subsidy for phosphorus and potassium fertilisers, including DAP, Mangrauthia said quoting government figures.
“Keeping in view of the costs involved and limited availability of the resource, developing varieties that minimise the fertiliser application and enhancing the phosphorus utilisation by plants would be the right approach,” said R M Sundaram, Director of IIRR.
Since these rice varieties are developed using traditional breeding techniques, no additional agronomic suggestions are advised to the farmers, he said.