Climate Smart Rice Varieties and Food Security

Technology, dissemination and adoption of technologies by farmers are the basis for sustainable agricultural productivity. Seed, fertilizer, management and irrigation technologies known as “Green Revolution technologies” have long played major roles in the growth of agricultural production in Bangladesh. The country has made remarkable progress in domestic rice production through the dissemination and farmers’ adoption of these technologies. Bangladesh is self-sufficient in rice production. Technological progress and dissemination of technology by the Department of Agricultural Extension has played a vital role to achieve self-sufficiency in rice production.

Farmers in Bangladesh cultivate rice in the three seasons Boro, Aus, and T.aman. Rice farming is highly vulnerable to extreme weather such as floods, droughts, tidal surges, cold wave, storm and cyclones. Growth and productivity of rice in coastal tropical areas are adversely affected by various abiotic stresses, including water stagnant, intrusion of sea water and flash floods. Soil salinity is therefore, considered one of the major constraints for rice production in these coastal areas of Bangladesh. Both soil and water are saline due to inundation of the offshore by tidal water and concentration of salt due to excessive evaporation during the dry season. Coexistence of saline soil, saline surface and groundwater and extreme temperatures (high and low) has made this ecosystem extremely challenging for successful rice production. A tidal surge accompanying the storm inundated vast tracts of land washing away thousands of homes, death of human and damaging standing crops, livestock and fisheries enclosures.

The total cultivable land in the country is about 1.40 billion hectares, among 1.0 million hectares of land are saline area and 2.6 million hectares are submerged land. According to a report on the environment of Bangladesh, the sea surface can rise up to 1.0 meter by 2050. As a result, about 3,000 million hectares of land would be permanently lost and overall production could be reduced by about 30 percent. Rice production is severely disrupted due to sudden floods, due to tides and cyclones and increased salinity in the cultivable land in various regions, especially coastal areas such as Satkhira, Bagerhat, Khulna, Barisal, Barguna, Bhola, Patuakhali, Jhalakathi, Pirojpur, Feni, Lakshmipur, Noakhali, Chattogram,Cox's Bazar and others.
In Bangladesh, we are very lucky our scientists have developed different high yielding stress tolerant rice varieties.

Salt-tolerant rice varieties: Bangladesh Rice Research Institute (BRRI) has released successful salt-tolerant varieties  (BRRI dhan 47, BRRI dhan 53, BRRI dhan 54, BRRI dhan 55, BRRI dhan 67,BRRI dhan 61, BRRI Dhan-97 and BRRI Dhan-99 for the Boro season; and Bangladesh Institute of Nuclear Agriculture (BINA) has released BINA dhan 8, BINA dhan 10 , BINA dhan 11&  BINA dhan 23.Global environment is changing Binadhan-10,Binadhan-11 &  BINA dhan 23  are climate smart stress tolerant high yielding rice varieties have saline tolerant and submergence tolerant up to 20 - 25 days capacity. Moderately salt tolerant rice varieties like BR23, BRRI dhan40 and BRRI dhan41 have limited adaptability in those areas. Salt tolerant rice varieties bring hope to Bangladeshi farmers. Bangladesh’s coastal districts which cover the country's 25% rice production."Salinity intrusion makes thousands of hectares of land barren in coastal Bangladesh. Wild Uri-Dhan (Porteresia coarctata) is found in the saline tolerant of coastal areas.

Submergence-tolerant: The low to medium high lands of this country, which account for 20 per cent of the total land, are completely submerged by floodwater during the monsoon. (BRRI dhan 51, 52 and 79; BINA dhan 10, BINA dhan 11 and BINA dhan 12), BRRI dhan51, BRRI dhan52, BRRI dhan79, BINA dhan11, BINA dhan-12. And BINA dhan 23 are tolerant to submergence.

Escaping Early Flash Flood: Short durated boro rice variety e.g. BRRI dhan 28 and BRRI dhan 45.
Late T.aman varieties: Low  land, are completely submerged by floodwater during the monsoon.  If flood damaged T.aman so, farmers have to transplant late varieties to compensate his loss of crop loss eg. BINA shail and others Shail varieties.

Drought-tolerant: Rice is sensitive to high temperature, especially at booting and flowering stages. Rice varieties tolerant of high temperature are rare, and only a few heat-tolerant rice varieties have been identified (BR 23, BRRI dhan 43, BRRI dhan 55, BRRI dhan56, BRRI dhan57, BRRI dhan66, BRRI dhan71, and BRRI dhan83 are resilient to drought.

 Cold Tolerant: The BR18, BRRI dhan36, BRRI dhan67, and BRRI dhan69 are some-extent resilient to cold.

Zn fortified rice varieties: BRRI dhan 62, BRRI dhan 64, BRRI dhan 72, BRRI dhan 74, BRRI dhan 84, BRRI dhan 100(Bangabandhu Dhan) and BRRI dhan 102; BINA dhan 20.

Anti oxidant rice variety: BR 5

Low glycemic index (GI) rice variety: BR 16, BRRI dhan 46 and BRRI dhan 69, BRRI dhan105 and BRRI dhan106. BRRI dhan105 is a low glycemic index (GI), or a diabetic-friendly rice variety suitable for Boro season and BRRI dhan106 is a high-yielding T.Aus season.
BRRI hybrid rice variety

BRRI Hybrid Dhan 1, BRRI Hybrid Dhan 2, BRRI Hybrid Dhan 3, BRRI Hybrid Dhan 4, BRRI Hybrid Dhan 5, BRRI Hybrid Dhan 6, BRRI Hybrid Dhan 7 and BRRI Hybrid Dhan 8

BRRI dhan 101 can prevent bacterial blight. BINA dhan 25 is a finer quality variety with an average trial output of 7.64 tons per hectare. This variety can be harvested in 145 days. BRRI dhan 98 is a short durated high yielding T. Aus varieties. These varieties can be grown to ensure food security.
Modern rice varieties have not been widely adopted in these areas and traditional varieties are still being grown by farmers because they can partially withstand floods and salt stresses, but they are low yielding; with long duration and are photoperiod sensitive. Furthermore, large area in this coastal zone remained fallow during the dry season (November–April) due to high soil and water salinity. Recently, several improved climate smart rice varieties were developed by the scientists but have not been disseminated on larger-scale in the region. So, for ensuring food security to disseminate these climate smart rice varieties as urgent basis.

Conclusion:

BRRI-developed rice varieties has released 113, BINA developed 25 rice varieties and Bangladesh Agricultural University developed 2 rice varieties which ensuring our food security. Due to climate change, saltwater intrusion poses a huge problem for rice cultivation in Bangladesh's coastal belt, because the local variety of rice is a saline-sensitive crop. Thousands of hectares of land have become barren in coastal Bangladesh because of salinity. Flood and salinity both problems exist in the coastal areas. Experts recommended BRRI and BINA released rice varieties to encounter these challenges. In co-operation with BRRI, BINA, BADC, NGO and DAE, are trying to disseminate this salinity and submergence tolerant varieties among the targeted farmers.

So, planners should come forward to address climate change impact in agriculture such as salinity and early flash flood, submergence, cold wave, drought to ensure our food security. We have to adapt with the climate change situation. Regarding adaptation options of coastal areas of southern part of Bangladesh.1.Rice based synchronized cropping pattern’s because we have climate smart rice varieties and rice cum fish culture preferred 2.Regarding saline water intrusion keep close sluice gate in the month of December 3.Rain water harvesting for irrigation 4. Address water stagnant situation in the field crops eg. Sunflower, Maize, Seasame, Water melon, Seasonal vegetables, Summer Tomatoes, Mungbean, etc here to develop drainage facilities in the field because most of soils are clay type. 5. If no crop can be grown go for fish culture in the suitable canals under the polders 6. Regarding sluice gate operations ensure coordination among the local communities, DAE and BWDB 7. Synchronized cultivation. The population of Bangladesh will reach near about 215 million in 2050. So food grain rice must be increased for upcoming future generation. If, we able to ensure community participation to address climate change situation, hope food and nutrition security will be achieved.


Dr. Jagot Chand Malaker is
Additional Director, Department
of Agricultural Extension,
Farmgate, Dhaka.