Sri Lanka’s agricultural sector contributed 8.4% to the annual GDP in 2025 while employing over a quarter of the nation’s workforce. As the sector expands, addressing disparities between research-level potential and field-level productivity is essential.
In an interview with The Sunday Morning Business, University of Peradeniya (UOP) Faculty of Agriculture Department of Crop Science Senior Professor Buddhi Marambe explained that improving agricultural output required a focus on climate-resilient crop varieties, nutrient-efficient production, and strong national policy and strategic action.
He further highlighted the necessity of strengthening extension systems to ensure that technological advancements and Research and Development (R&D) outcomes were effectively adopted by the farming community.
Following are excerpts:
Does Sri Lanka’s agricultural productivity remain below regional peers, and which crops show the largest productivity gaps?
Productivity is expressed in different terms, such as per unit of fertiliser applied or per unit of water used.
If we focus on land productivity, measured in metric tonnes per hectare, we must recognise that although we are in South Asia, the region is home to different ecosystem states. Sri Lanka has a total extent of about 67,240 sq km, containing three main climatic zones, seven agro-climatic zones, and 46 agroecological regions, indicating the diversity.
Thus, productivity varies dramatically from place to place. Soil type and terrain are the primary factors used to divide those seven microclimatic zones into 46 agroecological regions, and these play a determinant factor.
In order to show where Sri Lanka stands in field-level productivity, we can consider paddy as our staple food crop, maize as the main animal feed crop, and tea as our primary export agricultural crop.
In relation to paddy, we have performed very well in the past and will continue to do so. Bangladesh has maintained the leading position in paddy productivity over recent years, and Sri Lanka is closing the gap. India finds it difficult to break the 4 MT per hectare barrier, and other countries in the region fall below that.
In 2021, we produced about 4.8 MT per hectare, which dropped to 3.07 MT per hectare due to poor policy decisions. Last year, we reached about 4.3–4.4 MT per hectare, which is meaningful progress. Bangladesh has been sustaining an average yield of about 4.8–4.9 MT per hectare.
The picture is different for other crops, however. In relation to maize, Sri Lanka was performing well until 2021, with average yields of around 4.5 MT per hectare, while the country is barely at 3 MT per hectare at present. Countries like India, from which we import maize for animal feed, maintain high productivity and are performing well.
Tea presents its own challenges. For tea, the value is expressed in terms of manufactured tea per hectare. It takes about 4.65 kg of green leaf to produce 1 kg of manufactured black tea.
While we command high prices and are well regarded for quality, our average yield of manufactured tea sits in the range of 1,350–1,500 kg per hectare. This is considerably lower than India, which produces around 2,500 kg per hectare in most cases. There are reasons for this disparity, of course, but these figures provide a useful measure of where we stand.
How much of Sri Lanka’s yield gap can be addressed through R&D and improved agronomic practices?
Agronomic practices are part of R&D. When a recommended package is developed, it includes planting material and genetics, and the entire package is grounded in research. On yield improvement specifically for paddy, in 1940, our average yield was about 650 kg per hectare. By 2020 and 2021, that had risen to 4,800 kg per hectare, a significant increase over an 80-year period, which is actually a short timeframe for work of this nature.
This improvement is a direct result of our researchers’ efforts. The paddy varieties grown in Sri Lanka were developed locally. We do not import seed paddy; in fact, importing paddy plant material is prohibited in order to protect local varieties. We do not grow rice hybrids, and our varieties come through conventional breeding programmes that produce high yield potential – more than 8–10 MT per hectare and up to 12 MT at the research level.
At the research-station level, the potential is considerably greater due to well-managed conditions and maintenance of pure lines. When such variety is moved out of the research environment and into a farmer’s field, the conditions are different. This is a key reason for the gap between potential yield and field-level performance. There is also the issue of farmers following recommended management practices, and that challenge applies to paddy, maize, and tea alike.
A team led by me conducted a study for the Ministry of Finance with support from the World Bank. One of the important findings of the study was that, since the 2021 fertiliser ban, farmers have been applying less than 70% of the required urea for paddy.
Urea is the primary source of nitrogen. For a crop to produce at its optimal potential, it needs to be fed adequately through fertiliser, among other inputs; if inadequate quantities are being applied, the target yield cannot be expected. With the present fertiliser recommendation, our national average target is 5 MT per hectare. Reaching that target has been difficult mainly because crops are not being nourished in line with their nutritional requirements and prevailing soil fertility levels.
Tea follows a similar pattern. Unlike paddy, tea is harvested every 5–7 days, meaning nitrogen is continuously being removed through the green leaf and must be consistently replenished.
More pressing, however, is the age of our tea plants. An ageing plant population does not deliver expected yields even when nutrients are adequately supplied. Replanting has been recommended by the Government and the Tea Research Institute of Sri Lanka for decades, but it is not happening at the necessary scale due to the high costs involved. The land continues to degrade as old plants draw on available nutrients without yielding at expected levels.
Maize faces the same fertiliser constraints. The genetics are sound, but unlike paddy, we cultivate many hybrids that are typically imported. Sri Lanka has developed around five domestic hybrids, two of which showed promise, yet both failed during Cyclone Ditwah due to pollination problems; as a result, we lost a significant portion of the maize yield during the Maha season.
All of these factors have a bearing on the discussion of R&D and yield gaps. R&D is a continuous process. Developing a rice variety, for example, takes eight years. What is most needed right now across most of these crops is R&D directed at climate risk. That is the most important priority going forward.
Take paddy as an example. We have a large number of varieties, and the majority carry at least moderate resistance to most pests and diseases. Under extreme climatic conditions, however, they struggle. We do have drought-tolerant varieties, including three specific ones – Bg 251, Bg 314, and Bg 377. These are designed for high yields, but they limit yield reduction during a drought. In relation to tea, Sri Lanka released the TRI 5000 series around 2015–2016, which is a comparatively drought-tolerant cultivar in comparison to other cultivars.
We are now recognising the need for flood-tolerant rice varieties as well. Research is continuously evolving to meet these demands and in order to ensure the farming community can withstand a changing climate. Developing such varieties is precisely where R&D is indispensable.
It is worth noting, however, that cross-country yield comparisons are not always straightforward. In Sri Lanka, we produce high-quality tea by harvesting only one bud and two leaves. In India and Kenya, however, 3–4 leaves are harvested. We produce a smaller quantity of premium tea, while they produce larger volumes of a relatively low-grade product. This is in addition to other varying conditions, all of which affect overall productivity figures.
In R&D investment, there is a relevant metric called Gross Domestic Expenditure on Research and Development (GERD), which measures how much of a country’s GDP is directed towards research. In India, GERD across all research is about 0.64–0.66% of a very large economy. In Sri Lanka, our GERD stands at only about 0.1% of GDP. The percentage is already low, but the absolute expenditure is even smaller given the size of our economy. Economic constraints make it difficult to allocate more.
R&D produces the technological packages that reach the field, but when farmers do not follow the recommendations, a gap is created. We need farmers to adopt these packages while researchers continue to address climate challenges and develop varieties essential to sustaining productive agricultural systems.
What are the most urgent R&D priorities for the sector right now?
The most urgent priority area is climate change since all other factors fall within that framework.
There is also a pressing global challenge around fertiliser supply. Geopolitical conflicts are unpredictable, and while they are not always long-lasting, the uncertainty they create is real. Major priorities, therefore, involve nutrient-efficient production and developing varieties capable of performing well with reduced fertiliser inputs.
Sri Lanka must also focus on fertiliser packages; rather than relying solely on primary applications separately, we should be looking at third- and fourth-generation fertilisers, slow-releasing compounds that allow crops to absorb nutrients more effectively. Continued research into producing or importing high fertiliser-use-efficiency products is necessary to enable crops to achieve strong productivity within shorter timeframes.
In terms of commercialising agricultural innovation, specifically for smallholder farmers, what mechanisms are needed to ensure these advancements are accessible?
Considering our three main crops once again, in paddy, the increase was driven by new varieties, which are themselves an important technology; farmers had the confidence to adopt these.
Today, over 98% of paddy-cultivated land in Sri Lanka uses high-yielding varieties developed by our own scientists. Farmers produce much of their own seed. The Government only accounts for about 16% of certified seed paddy production and supply, while farmers produce the remaining 84%. Having that genetic material available locally reduces reliance on imports during a crisis.
With maize, the initial productivity boost came from imported hybrids. Relying on imports of planting material, however, carries risk during periods of global disruption. Sri Lankan scientists have since developed maize hybrids.
The private sector is also engaging in such ventures. Private organisations are investing in seed development because it is commercially viable and contributes to national food security. In tea, the clones and cultivars in use are grounded in our own research, and having that genetic material developed locally is something to be proud of.
Commercialisation succeeds when farmers adopt these technologies. The Department of Agriculture has historically maintained a strong extension programme to facilitate uptake of new technologies, which continues to this day. When the private sector enters, it runs its own demonstration programmes to promote variety adoption.
Education and awareness, however, remain ongoing requirements. We need continuing professional development for the farming community and must identify location-specific performance characteristics for the varieties we release. A strong extension system, whether through direct engagement or digital platforms, is essential to bridge the gap between researchers and farmers. If a variety fails in a single season, the long-term investment is lost.
Moreover, since 2015, the Department of Agriculture has progressively opened varieties, including the MICH Hy-1 chilli, to private sector participation. The department made these parent varieties available to private sector organisations and individual farmers free of charge. Hybrid seed producers usually guard parent varieties closely because they are the most cost-intensive part of the process, and this approach has resulted in tangible success.
Therefore, when a good product is successfully adopted by the farming community, that is the real measure of commercialisation success.
How are cropping systems utilised in Sri Lanka, and what are the comparative advantages of different approaches?
Cropping systems vary, but broadly there are two main types; monocrop and multiple, or mixed, crop systems. A monocrop system – such as paddy – involves cultivating the entire land area with a single crop.
In a multiple or mixed crop system, different crops are grown within the same area, and its comparative advantage is resilience; if one crop fails due to a pest incident, others may survive, giving the farmer both income and food security. While this system does not apply to every crop, it is important to improve land productivity.
Given recent and potential environmental challenges, how can Sri Lanka strengthen its climate-resilient farming practices?
Climate resilience has two main approaches: adaptation and mitigation. Adaptation means using available technology to continue farming effectively within a changing climate, while mitigation involves reducing greenhouse gas emissions. For a country in our position, adaptation is the more immediate priority, as mitigation technologies carry significant costs.
I led the adaptation team for Sri Lanka’s Technology Needs Assessment and Technology Action Plan, as well as the adaptation component of the Nationally Determined Contributions (NDC) in 2025. We identified adaptation techniques across 10 and mitigation techniques across six economically important sectors.
In agriculture, genetics are central. Developing seed varieties that can withstand both moisture deficits and excess, in addition to high temperatures, is essential. Even with good varieties, complementary technological packages are needed to support crops in the field. This includes practices such as mulching – to retain soil moisture – and micro-irrigation technologies such as drip irrigation. Fertigation – the application of fertiliser through micro-irrigation systems – is another option. These are key in crop production.
Climate-resilient farming systems are essential, as they will be the future, and our existing recommendations need to be updated to reflect this increasingly variable climate. R&D plays a crucial role in this regard.
Which policy perspectives must be prioritised to ensure these agricultural strategies are effectively implemented?
Policies carry statements of intent, but they require strategic frameworks and action plans to be effective. At present, Sri Lanka does not have a strong national agriculture policy. What we tend to see are reactive, crisis-driven responses, which point to the absence of a long-term framework.
After various efforts, a National Agriculture Policy (NAP) was refined in 2023 and went through public hearings and committee review, but it has not yet been formally implemented. The Government can revisit this and align it with the current national development agenda while accounting for new global tensions.
Sri Lanka requires a long-term mission backed by a strategic approach if we are to see results at the ground level. Sri Lanka has a well-structured multi-tier administrative system, from the national Government down to the grama niladhari level. These layers should be used to assign clear responsibilities and ensure that agricultural policy is communicated and applied effectively at the grassroots. Only then can the country’s national goals for the sector be achieved.