Stress-tolerant rice to help farmers win drought, submergence
Shahidul Islam Chowdhury
Farmers in drought-prone regions of Bangladesh can now look forward to a more bountiful rice harvest, with two drought-tolerant rice varieties — BRRI dhan56 and BRRI dhan57 — released recently, as the wet season ends and water becomes scarce, International Rice Research Institute said Friday.
Two newly developed submergence-tolerant varieties of rice — BRRI dhan-51 and BRRI dhan-52 — have also been cultivated this Aman season in a large-scale ushering in a new era of boosting rice production in the country.
Unlike most rain-dependent rice varieties in Bangladesh planted in the Aman monsoon season from July to November, BRRI dhan56 and BRRI dhan57 remain healthy amid drought, which can occur towards the end of the season, because they take a shorter time to mature than other popular local varieties.
Because of this early maturity and good grain quality of BRRI dhan56 and BRRI dhan57, farmers can harvest more rice and get high-value rice from these two varieties when drought occurs, according to an IRRI press release issued from its headquarter Manila.
Drought-like-situation has been one of the biggest enemies of Bangladeshi farmers, so much so that the country has a record of drought spells with historical significance dating back to the 1700s. In 1999, Bangladesh suffered the longest drought in 50 years, with more than four months without rain, and, in 2010, the country recorded its lowest rainfall since 1995.
‘Equipping Bangladeshi farmers with rice varieties that can tolerate dry conditions will be vital if we want to help people avoid poor harvests, which can increase the incidence of poverty,’ IRRI representative in Bangladesh Mohammed Zainul Abedin said.
‘Climate change is likely to increase the occurrence of extreme weather events such as drought,’ he said.
BRRI dhan56, developed by IRRI, is the first drought-tolerant rice variety released in Bangladesh that can provide from 0.8 to 1.2 tonnes per hectare more yield than the presently cultivated varieties despite three weeks of no rain.
The other variety, BRRI dhan57, was developed by the Bangladesh Rice Research Institute. This variety also possesses a similar yield advantage despite the absence of rain for two weeks.
Both varieties were tested in the drought-prone Rajshahi region and are now being released in the northern districts of the Barind Tract — Rajshahi, Chapainawabganj, Natore and Naugaon.
The varieties are also of economic significance to other districts that are known drought hot spots – Kushtia, Magura, Chuadanga, and Jessore – where rain seldom occurs and is erratic and uncertain during the last week of September and in October when rice plants need water.
Arvind Kumar, IRRI rice breeder for drought tolerance, said, ‘Both varieties are also resistant to blast – a common rice disease in Bangladesh – and have good grain quality.’
In a participatory evaluation, farmers’ feedback shows that they prefer these varieties as they also cater to their local needs, claimed scientists.
Farmers not only from the northern region but also the southern regions of Bangladesh are likely to appreciate BRRI dhan56 for its colored grain type like Swarna, a popular high-yielding South Asian variety, BRRI rice breeder Tamal Aditya Lata said.
‘On the other hand, some farmers will also choose BRRI dhan57 for its long and slender grains,’ she said.
Though BRRI dhan-51 and BRRI dhan-52 were released only last year, they have been cultivated on a vast tract of land as the government, private sector as well as farmers produced enough seeds within a short period of time, the Seed Wing director general, Anwar Faruque, told public news agency Bangladesh Sangbad Sangstha.
He said farmers in the low-lying areas suffer most as their cultivated paddy fields were submerged by flood waters almost every year, which hampers paddy production to a great extent.
Bangladesh Rice Research Institute director Khairul Bashar said normal yield of BRRI Dhan-51 and BRRI Dhan-52 is 5 to 5.5 tonnes a hectare, but when submerged, the yield is 4 to 4.5 tonnes.
The newly developed submerged varieties can survive maximum 18 days after inundation but it depends on the quality of water, temperature as well as environment, Bashar said.
BRRI dhan 51 and BRRI dhan 52 were cultivated in Sirajganj, Rangpur, Kurigram and Gaibandha this Aman season, according to the Department of Agriculture Extension.
Bashar said the BRRI was giving priority to developing stress-tolerant rice with a view to increasing rice production to ensure food security amid threats of climate change in the country.