Global role of Sri Lankan rice to feed the world
Why was ancient Sri Lanka called the granary of the East despite the presence of many other rice growing countries which were much larger than ours in the region? History reveals that Sri Lanka maintained a far-sighted philosophy, technology and culture associated with rice production and its impact was felt well beyond the shores of this island. Rice cultivation was the basis of the economy and wellbeing of the nation. Food security was the key pre-requisite of the national security. The famous saying of King Parakumba, the Great, that ‘not a drop of water that falls on the land be allowed to flow into sea without being used by humankind’ depicts this strong philosophy.
Marvelous ancient irrigation infrastructure and social model consist of village-temple-tank –dagaba depicts the technology and culture associated with rice. Vast varietal diversity of rice with underlying enormous genetic diversity, which is un-proportionate to the size of our small land, further qualifies it to hold the title of the granary of the East. Recent findings of the existence of modern man (Homo sapiens L.) around 100,000 BC in Sri Lanka may even lead to re-write the history of rice domestication. The oldest record of rice domestication was so far traced back to 12000 BC in China. Unfortunately, the colonial leaders in the past paid scant attention to growing rice and diverted state patronage to cash crops.
Infrastructure built by our great kings was abandoned or used for other purposes. Rice yields dropped to an annual average of 0.2 million tons during 1850-1900 AD. Granary of the East lost its glory and the result was a downtrodden nation, which was looking out at neighbouring countries to get their staple food. Thanks to the efforts of the Department of Agriculture and the policy makers, Sri Lanka achieved self-sufficiency in rice in 2005 by crossing 32 million tons of annual rice production. Several other nations in the region reached this milestone in parallel. This achievement was relied heavily on adoption of modern science and technological applications and, hence, incurred considerable cost on environment and human health in the long run.
Traditional methods abandoned We abandoned cultivation of traditional cultivars and traditional systems of cultivation to move into improved plant types with high yield to meet escalating demand by the increasing population in the 1970/80s. These improved rice cultivars were bred in such a way that they perform well with inputs of agro-chemicals such as chemical fertilisers. Obviously, risk of human health is associated with usage of agrochemicals on rice. Achievement of self-sufficiency in rice production by our nation is a significant achievement in the quest for food security but is not the ultimate goal. In view of a projected increase of the rice eating population world over, in the near future, there is a big thrust to look for avenues to further increase rice productivity. Development of rice to meet specific consumer preferences for niche markets is a necessity with high prospects.
Development of healthy-rice as a preventive measure against noncontagious diseases such as diabetes, etc is feasible as we have several traditional rice varieties with known medicinal properties. We also have to look into developing rice cultivars that perform well without or with least amount of chemical inputs such as fertiliser and other agro-chemicals. Most characters that contribute to high yields may become unstable with time and need to be upgraded with new genetic resources. The presence of vast genetic diversity in our rice cultivars is indispensable tools as well as a primary requirement to continue with rice improvement programmes. We are proud owners of that treasure of genes! They are essential in improving rice productivity to face looming challenges such as drought, salinity, heat, nutrition, pest and diseases posed by impending climate change and population rise.
Genes
Having a gene for a particular trait, for instance drought tolerance, is a primary requirement in improving rice. But this presence does not guarantee the functionality unless the gene has a specific functional configuration in the made-up or DNA sequence (also called allelic form of the gene). Not all rice cultivars harbour this particular functional configuration. It may occur only in five cultivars out of whole set of rice cultivars in our country (germplasm). If we failed to find or conserve those five cultivars, that functional gene could vanish from our rice gemplasm. Any entity which discovered this functional gene can claim IP rights and use it to develop (eg; drought tolerant) rice cultivars. Interestingly, rice has the smallest genome among the cereals and makes it relatively easy to carry on genomic studies to discover genes for various traits/characters.
Thus discovered rice genes are equally useful in improving the germplasm of other cereals such as wheat and maize. This indicates the wider commercial scope in rice genes. In short, the failure to identify functional genes in our germplasm is as disadvantageous as having a germplasm with eroded genes. No one is to blame for this failure except ourselves as this situation occurs due to lack of farsighted vision to invest and explore our rich genetic resource in rice. It is, indeed, high time to re-align national rice research programme prioritizing genome scale studies for future rice improvement programmes. Considerable investment has to be made with long-term vision to train scientists and develop infrastructure including those for Bioinformatics to achieve this goal. Did you know that Sri Lankan rice cultivars, besides their role of feeding our nation, are shouldering the quest to fight global hunger in other countries?
Rice cultivars
Several rice cultivars developed in Sri Lanka are cultivated at a considerable scale in 15 other countries across the globe to meet their demand of hunger. This global mission of Sri Lankan rice has been carried out through the cooperation of the International Rice Research Institute (IRRI) in Philippines. It is the premier international institute that acts as the hub of rice research and development. IRRI carries out its mission to develop rice farming to fight off global hunger and poverty in partnership with all rice growing nations. Sri Lanka has been contributing to the mission of IRRI from its inception in 1960s by donating its rich genetic resource of rice cultivars. Despite being a small country a total of 2286 Sri Lankan rice accessions which consist of improved cultivars, traditional varieties and wild relatives are deposited in the Rice Gene Bank of the IRRI. Our nation is the fourth largest donor in terms of accessions per 1000Km2 of rice cultivars in the IRRI (Fig1).
Interestingly, about 25 rice cultivars developed in our country have been distributed to other countries through the IRRI. Rice cultivar named as Bg90-2 is the most widely adopted across the countries. It bears at-least eight alternative names in different countries. Bg90-2 has been released in 12 Asian (China, India, Myanmar, Nepal) and African (Benin, Cotê d’lvoire, Gambia, Ghana, Kenya, Nigeria, Sierra Leone, Tanzania) countries. These countries represent a wide diversity of agroclimate, soil types, cultural methods, and consumer preferences. Global mission of Bg90-2 is accompanied with some other Sri Lankan cultivars such as Bg400-1, Bg380-2, Bg367, BW293, BW298 and LD183, etc (Fig 2). Adoption of a rice cultivar successfully in foreign soils indicates its wider scope of enduring agro-climatic variation as well as serving to the array of consumer preferences. Moreover, this provides strong evidence for rich genetic diversity in our rice and also the competency of Sri Lankan rice breeders in rice improvement.
Sri Lanka’s contribution
The contribution of Sri Lanka to the quest of fighting global hunger is acknowledged in one of the IRRI publications in 1998 as, “It is heartening to note that some relatively smaller NARS (National Agricultural Research Systems), such as Sri Lanka, have been very successful in contributing to the release of varieties. Sri Lanka provided 25 varieties, which were released in other Asian, African, and Latin American countries”. Fig 2 Sri Lankan rice cultivars with given names (in parenthesis) in different countries Besides being used for cultivation, Sri Lankan rice cultivars have been used in scientific experiments to find solutions for various challenging issues in rice cultivation. For instance, traditional rice cultivars being used in breeding and mapping programmes aims at identification of genes that are responsible for particular traits; such as those for tolerance to abiotic stresses (drought, salinity etc). For instance, the Goda Heenati was shown to posses the break-through rice gene called Sub1 that enables rice to withstand submergence for 14 days without compromising yield. Moreover, 49 Sri Lankan rice cultivars consisting mainly of traditional rice varieties have been included in the 3000 rice genomes sequenced by the IRRI and are made available for comparative genomics and gene discovery process world-over.
The contribution of Sri Lanka towards the IRRI is not unilateral, as there are mutual benefits in the IRRI-Sri Lanka relationship. Rice improvement programmes of Sri Lanka were significantly benefited by its relationship with IRRI. Several rice cultivars including the omnipresent Bg90-2, were developed using the parental material obtained from the IRRI (table 1). Bg300, one of the three popular rice cultivars that are cultivated extensively in Sri Lanka, also has an IRRI-cultivar in its ancestry. In the recent past the Rice Research and Development Institute of Sri Lanka (RRDISL) has been building a healthy relationship with IRRI. Some research and development projects for example the Closing Yield Gap in Rice (CORIGAP) are being conducted as collaborative projects between RRDISL and IRRI.
SL rice scientists
Several Sri Lankan rice scientists and technicians obtained short-term training in various fields of rice science from the IRRI. However, there is an opportunity to strengthen this relationship into an effective partnership between Sri Lanka and IRRI to enhance these mutual benefits further. This will facilitate our scientists to be in the forefront of rice research and make strong opinion in aligning these collaborative projects with the goals of national agriculture plan. Many countries in the region such as India, Japan, China, Bangladesh, Thailand, South Korea, Myanmar, Vietnam and several African countries have invested heavily on rice research programmes. Most of these countries developed effective research partnerships with IRRI in complementary to the strong national rice research programmes of them. They have in-house scientists from the IRRI to fine-tune the synergism between IRRI and respective countries. India has IRRI experimental stations and laboratories.
This facilitates these countries to carry on rice improvement programmes with extra-vigour and also create the environment to address global issues in a mutually beneficial way. Sri Lanka is not too late yet to take steps to adopt genomic scale researches in rice. We have a vast genomic diversity in rice to explore and identify genes that are crucial for future rice improvement programmes to serve the global issues. Further delay in this process will deprive us of getting competitive advantage of gene discovery programmes. Development of a broader vision for future rice research programme in this post-genomic era is a need of the time. The plan of such a mission should stretch well beyond the traditional boundaries at present into the international sphere of rice research.