Rice of hope

Scientists breed 3 new high-yielding varieties of rice that can withstand drought, salinity, cold weather up to a certain level

Researchers have developed three early-maturing varieties of rice that can withstand up to a month of rainless days and moderate levels of salinity and cold bite.
Bangladesh Rice Research Institute (BRRI) has recently released the three high yielding varieties (HYVs) -- BRRI dhan-55, 56 and 57.
Officials of BRRI and the Philippines-based International Rice Research Institute (IRRI) that provided technical support for the research disclosed this to The Daily Star yesterday.
BRRI dhan-55 is a moderate salinity and cold-tolerant variety with a per hectare yield of seven tonnes compared to six tonnes of BRRI dhan-28, the most popular rice variety in Bangladesh, said Dr Tamal Lata Aditya, a chief scientific officer at BRRI.
The new variety is equally suitable for cultivation in the salinity-prone southern region and cold-hit northern region of the country, she said.
Tamal, involved in a joint breeding research initiative of IRRI and BRRI, also said BRRI dhan-56 and BRRI dhan-57 are capable of withstanding rainless days up to one month.
With this latest rice breeding developments, BRRI begins its annual research review workshop today at its Gazipur headquarters.
An IRRI release said, "Farmers in drought-prone regions of Bangladesh can now look forward to a more bountiful rice harvest as the wet season ends and water becomes scarce, with two recently released drought-tolerant rice varieties-- BRRI dhan-56 and BRRI dhan-57."
Unlike most rain-dependent rice varieties in the country planted in Aman season (monsoon) from July to November, BRRI dhan - 56 and 57 remain healthy during drought, which can occur toward the end of the season, because they take a shorter time to mature than other popular local varieties, said IRRI.
Drought has been one of the biggest problems of farmers in Bangladesh. In 1999, the country suffered the longest drought in 50 years --more than four months without rain -- and in 2010, it recorded its lowest rainfall since 1995.
IRRI rice breeder for drought tolerance Dr Arvind Kumar, who pioneered the breeding research that eventually enabled BRRI to release the two drought-tolerant rice varieties, said, “Both varieties are also resistant to blast -- a common rice disease in Bangladesh -- and have good grain quality.”
Tamal, who worked with Arvind, told this correspondent yesterday BRRI dhan-56 can withstand rainless days up to one month and the grains mature in 107 to 110 days during Aman season even when the water table depth goes down to 70-80 cm.
BRRI dhan-57 can withstand drought up to three weeks but the grains mature even earlier -- in 100 to 105 days.
"This means jute farmers can go for late Aman production with this variety while potato growers can think of reaping the paddy quickly and free the land for winter vegetable prior to cultivation of the next Boro rice," explained Tamal, who heads the BRRI Regional Station in Comilla.
“Climate change is likely to increase the occurrence of extreme weather events such as drought,” said Dr Mohammed Zainul Abedin, IRRI representative in Bangladesh.
“Equipping Bangladeshi farmers with rice varieties that can tolerate dry conditions will be vital," he added.
IRRI has recently helped some other countries release some drought-proof varieties -- Sahbhagi dhan in India, Sahod Ulan-1 in the Philippines and Sookha dhan in Nepal.