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A fungal disease threatens rubber cultivations in high rainfall areas

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A CLSD/PLD affected rubber cultivation in June 2023. Note that more than 50% of new leaves developed in February/March has fallen by June.

By Emeritus Professor Asoka Nugawela
(Former Director, Rubber Research Institute of Sri Lanka)

A new addition to the list of economically important diseases affecting natural rubber cultivations in the country is Circular Spot Leaf Disease (CLSD). It is also known as Pestalotiopsis Leaf Disease (PLD). This fungal disease was first reported in Sri Lanka in 2019 and by 2021 it had spread to around 20,000ha. Currently the affected extent is much higher. The disease severity is found to be more in rubber growing areas receiving a high annual rainfall with a higher number of wet days (Fig. 1). As per the rubber growers in such wet areas the new disease has caused around 30% loss in rubber production. Further the disease has also retarded the growth of young rubber plants. These situations are despite of the disease management programs undertaken incurring high costs. The rubber growers also fear that if this disease continues leading to secondary leaf fall the rubber plantations will become very weak leading to uneconomical rubber yields and poor growth rates in young rubber cultivations. Prolonged immature periods will result in high capital costs and lower the return on investments. At national level the rubber production will decline compelling the rubber product manufacturing sector of the country to import this raw material using scarce foreign exchange. The national rubber production has declined by nearly 6,000 MT from 2021 to 2022. The value of this production loss in 2022 is around 12 million US$.

Disease management

Based on research conducted by the Rubber Research Institute of Sri Lanka two of fungicides are currently recommended for the management of the disease. In the initial interim recommendation of the institute, the concentration of the fungicides is 3 g/ml per liter of water. Subsequently it was increased up to 5 and then again to 10 g/ml expecting to get a better control. In addition to the chemical control, the necessity to adhering into other important agronomic practices such as soil management, weed management, fertilizer application and harvesting is emphasized to enhance growth vigor and disease resistance of the trees.

High costs of the chemicals, spraying of the fungicides to cover the entire canopy of the tall rubber trees and continuous wet weather prevalent in traditional rubber growing areas are some constraints faced by the growers to adopt the chemical control of the disease. After application of the fungicides at least a 5-hour dry period is needed to prevent chemicals getting washed away.

Disease severity

It is clearly evident that since the first appearance of the disease in 2019, the disease severity has shown an increasing trend especially in the relatively more wet rubber growing areas. This is true in both young and mature rubber cultivations. Generally, in mature rubber the full quantum of leaves is present soon after re-foliation in March/April each year. Subsequently with the onset of monsoonal rains the disease incidence take place leading to leaf fall. Disease severity surveys undertaken by a particular plantation management company managing around 3,000 ha of mature rubber in the wetter region clearly shows the progression of the disease since its first detection (Table 1). Surveys had been undertaken in the month of December in each year prior to the onset of wintering.

Out of the total tapping blocks only 21% showed 76 to 100% secondary leaf fall by December 2020. However, in December 2022 this figure was 67%. Hence certain tapping blocks have shown more than 76% defoliation for three consecutive years which will invariably lead to the weaking of such trees leading to less growth and crop production. (See Table 1)

Impact on rubber production

The trend in land productivity of rubber plantations located in the relatively dry and wetter regions managed by this company reveal the impact of CLCD/PLD on the rubber production. Whilst the land productivity shows a gradual increasing trend in the relatively dry regions where the disease is not prevalent, it declines significantly in the wetter region. In both drier and wetter regions, the agricultural practices adopted are similar. Hence it is apparent that CLSD/PLD has led to around 30 to 35 % decline in rubber production in the disease affected areas (Table 2). This decline in rubber production could increase further in the coming years if the disease persists leading to secondary leaf fall. It should be stated that in the financial year 21/22 there were reasons other than CLSD/PLD to lower the land productivity. (See Table 2)

Interventions needed

As shown previously, the severity of the disease, is in an increasing trend since the initial year of infection. The significant negative impact on latex production and growth of young rubber plants are a serious threat to the sustainability of the rubber cultivations in the country, financial performance of investors/growers and the national economy. The potential consequences to the growers, investors and to the economy of the country is too significant for this issue challenging the industry to be taken lightly. Hence the government should be mindful of the consequences of this problem faced by the industry and extend its fullest corporation to the relevant government institutions and departments to come out with suitable a solution. The main strategies to be considered in combating this disease are chemical control methods which includes effective chemicals and application methods, identifying resistance varieties/clones, developing mixed cropping systems, agroecological zoning for crops and escaping from the disease by promoting growing of rubber in regions of the country where this disease is not prevalent to the extent to make rubber cultivations uneconomical.



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Opinion

Transformation of agro-food system:

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A culture-based local solution for Sri Lanka

BY Prof Nimal Gunatilleke

The Thirty-seventh Session of the UN-FAO Regional Conference for Asia and the Pacific (APRC) is being held as a high-level Ministerial in-person event in Colombo, Sri Lanka from 19 – 22 February 2024. This was preceded by the Senior Officers Meeting (SOM) held virtually from 31 January to 2 February 2024.

This year’s conference, themed “Transformation of the Agro-Food System,” will delve into key areas such as promoting nutritious food production, ensuring food security, enhancing food production, safeguarding the environment, curbing greenhouse gas emissions, and mitigating climate change risks.

This regionally significant meeting of the Food and Agriculture Organization of the United Nations is being held in Colombo at a time when Sri Lanka is struggling to keep its head above water in the post-COVID era knocked down for the second time in quick succession by her economic crisis.

A government report and data from the health ministry quoted by Reuters indicates that the people in Sri Lanka are currently burdened with soaring prices, including food, largely caused by its worst economic crisis since it gained independence in 1948.

According to the Central Bank Report ‘rising malnutrition among children has become a forefront policy concern in Sri Lanka amidst heightened food insecurity of households caused by the host of economic and social issues that exacerbated during the economic crisis in 2022’.

The following human health statistics extracted almost verbatim from the Reuters report on Jan 18, 2023, are equally disturbing, to say the least.

The number of children grappling with various forms of undernutrition in Sri Lanka has increased for the first time in at least six years in 2022.

More than 43.4% of the country’s children under 5 years of age are suffering from nutrition problems, according to the report released in October, with 42.9% suffering from some form of undernutrition.

Data available on the website of the health ministry’s Family Health Bureau indicate that the percentage of children under five who are underweight, stunted (low height for age), or wasting (low-height for age) increased in 2022 after dropping steadily since at least 2016.

According to the World Health Organization (WHO), malnutrition refers to deficiencies or excesses in nutrient intake, imbalance of essential nutrients, or impaired nutrient utilis ation.

ASIA AND THE PACIFIC REGIONAL OVERVIEW OF FOOD SECURITY AND NUTRITION STATISTICS AND TRENDS

According to the World Bank statistics, Sri Lanka ranked the second worst affected country in the South Asian region in terms of wasting among children under five years. Further, underweight among the same group of children remained around 20.0 percent since 2000, while no significant advancement was reported in terms of children with stunted growth.

Meanwhile, the persistent disparities in malnutrition prevalence across regions and economic sectors in the country suggest that nutrition anomalies remain unresolved for a prolonged period. Across residential sectors, the estate sector has become the most vulnerable sector with the highest prevalence of stunting and underweight children under five years. According to the DHS-2016, around 31.7 percent of children in the estate sector are stunted, compared to 14.7 percent in urban areas and 17.0 percent in the rural sector. Particularly child malnutrition represents a deep concern that carries a generational burden.

UNDERNOURISHMENT AND FOOD INSECURITY: SUSTAINABLE DEVELOPMENT GOAL 2.1

A yet another alarming set of nutrition statistics has been published in the Asia and the Pacific Regional Overview of Food Security and Nutrition, in December 2023 in addressing the Sustainable Development Goal 2.1: UNDERNOURISHMENT AND FOOD INSECURITY.

The percentage of people unable to afford a healthy diet in Sri Lanka was 54% in 2020 and the figure has been increasing ever since.

Prevalence of undernourishment in Sri Lanka is 5.3% (cf. India 16.6%)

The prevalence of moderate or severe food insecurity during the period 2020–2022 in Sri Lanka has been 10.9% (cf. Bangladesh 31.1%)

Undernourishment is defined as the condition of an individual whose habitual food consumption is insufficient to provide, on average, the amount of dietary energy required to maintain a normal, active, and healthy life. The indicator is reported as a prevalence and is denominated as “prevalence of undernourishment”, which is an estimate of the percentage of individuals in the total population who are in a condition of undernourishment.

People affected by moderate food insecurity face uncertainties about their ability to obtain food and have been forced to reduce, at times during the year, the quality and/or quantity of food they consume due to a lack of money or other resources.

MALNUTRITION: SUSTAINABLE

DEVELOPMENT GOAL 2.2:

This section reports on four global nutrition indicators: stunting , wasting in children under 5 years of age, and anaemia in women aged 15 to 49 years.

The prevalence of stunting among children under 5 years of age in Sri Lanka in 2022 has been 15.9% (cf. India 31.7%).

The Prevalence of wasting among children under 5 years of age from 2015 to 2022 in Sri Lanka has been 15.1% (cf. India 18.7%)

The Prevalence of overweight among children under 5 years of age in Sri Lanka is 1.3% in 2022 (cf. 2.8% in India).

ANAEMIA AMONG WOMEN AGED 15 TO

49 YEARS

Prevalence of anaemia among women aged 15 to 49 years in Sri Lanka in 2019 has been 34.6 % (cf. India 53%).

HEALTHY DIET AT NATIONAL SCALE

In this regard, notable transformations in the country’s food system are essential to deliver a healthy diet for people at an affordable price. These include improving productivity in the agriculture sector along with more innovations and research and development, reducing post-harvest losses, more value addition in the agriculture sector, reducing import dependency on food systems, introducing climate-resilient food crops, promoting a wide range of nutrient-rich foods, particularly through the popularising integrated farming, rebalancing agriculture sector subsidies, and tax policies and improving agronomic practices as well as maintaining adequate food buffers to face food emergencies.

Among the solutions provided at the national level include the provisioning of school meals, provisioning of food/cash allowances for pregnant and lactating mothers, the Thriposha program, school water sanitation, and hygiene programs, and the salt iodization programme, among others. Reflecting the impact of these efforts and commitments spanning over several decades, malnutrition among children declined remarkably during the period from 1975 to 1995, with stunting among children below five years of age almost halved to 26.1 percent in 1995, compared to 49.9 percent in 1975, while the underweight child population declined to 29.3 percent in 1995 from 57.3 percent in 1975. However, these trends have reversed since the double whammy started in 2021 with COVID-19.

In addition, some of the small-scale community-level initiatives established under the supervision of the Department of Agriculture such as Hela Bojun Hal (Native Food Courts) are gaining popularity in several provinces in Sri Lanka. These food courts serve a variety of nutrient-rich native food preparations using rice flour, finger millet, local vegetables (leafy porridge), and many other sweetmeats prepared by local womenfolk and sold at an affordable price. Also, there are many beverages and local fruit drinks that are equally popular among the customers.

These food courts providing healthy and nutritious meals are making steady inroads into the food and beverage trade among the health-conscious public from all walks of life including schoolchildren, university students, and blue- and white-collar workers, alike which is indeed an encouraging trend.

If these types of Hela Bojun food courts could be promoted in rural as well as urban schools with the participation of the parents of the schoolchildren under the direction of the school administration and local health and agricultural authorities, it may help to address some of the issues under discussion at the on-going UNFAO-Asia Pacific Regional Conference such as undernourishment, food insecurity, and malnutrition. At the same time, it may give a shot in the arm for promoting nutritious food production while ensuring food security befitting the theme of this year’s UNFAO-Asia Pacific Regional Conference, which is “Transformation of the Agro-Food System”.

Sri Lanka as the host country’s special ministerial event for this conference has put forward her theme as ‘Agro-tourism in Asia and Pacific – accelerating rural development and enhancing livelihoods’ showcasing agrotourism most likely in the world-renown Kandyan Spice/Home Gardens and as a spin-off of this, the local food courts utilizing these home garden produce too, can be highlighted at the same time.

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Opinion

Harin batting for India

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The Minister of Tourism, Harin Fernando, has stated that the Sri Lankan Government will be handing over the operation of Mattala International, Ratmalana International and Colombo International Airports to India. He has added that Sri Lanka is a part of India! Has he lost his senses?

Separately, should it not be the role of the Minister of Ports, Shipping and Aviation Nimal Siripala de Silva to make such a far-reaching decision?

Mattala, Ratmalana and Colombo are the three main airports of entry to Sri Lanka. Giving their management over to Indian organisations is tantamount to putting the proverbial snake inside one’s sarong and complaining that it is stinging.

What then will be the future of Airports and Aviation Sri Lanka (AASL)? They are, in any case, a ‘service provider’.

It is the responsibility of the government of Sri Lanka through its regulator, the Civil Aviation Authority Sri Lanka (CAASL), to adhere to International Civil Aviation Organisation (ICAO) requirements and regulations. Will this be compromised?

The International Air Transport Association (IATA) guidelines for airport governance declare that the State (in this case Sri Lanka) must be accountable irrespective of national, legal or regulatory framework, or airport ownership and operating model. Could that be ensured under this recently announced arrangement?

Such accountability must be guaranteed by enactment of primary legislation in the aviation sector, mindful of the adage that a chain is only as strong as its weakest link. I believe that the Legal Draughtsman’s Office will take an inordinate amount of time to deliver this guarantee, amongst other things.

There is also the matter of establishing an effective regulatory framework with CAASL to monitor technical/safety and economic performance of the aviation sector, and compliance with International Civil Aviation Organisation (ICAO) obligations, Standard and Recommended Procedures (SARPs), and policy guidance.

In my opinion CAASL is not yet capable of that. In a combined operation such as this, IATA stipulates “Awareness and mitigation of potential conflicts of interest inherent in the regulatory framework or ownership and operating model through clear separation of powers, for example conflicts between economic oversight and shareholding arrangements, and separation of regulatory and operational functions”.

So, it is not an ‘open-and-shut case’, as Fernando believes. It is complex. His optimism is amazingly unrealistic, to say the least.

Remember, certification of aerodromes by the technical/safety regulator under ICAO requirements will continue to be carried out by CAASL as at present. According to the Organisation of Professional Associations (OPA), report Sri Lankan regulators tend to be more “obstructive” than “facilitative” when it comes to certification. CAASL needs to be revamped for greater efficiency.

Other refinements involve the independence of regulatory authority (CAASL) from government, and striving for separation of economic regulation from technical/safety regulation. CAASL was formed under the ‘Private Companies Ordinance’ but unfortunately it has drifted back to conducting its business as a regular government office, with political interference and all.

Besides, it is vital to establish an Aircraft Accident Investigation Authority, preferably independent of the CAA. Annex 13 to the ICAO convention says: “The State shall establish an accident authority that is independent of the aviation authorities and other entities that could interfere with the conduct or objectivity of an investigation.”

That, I believe, is what ‘checks and balances’ are about.

Meanwhile, the silence of the Aviation Minister is deafening.

The proposed ‘Indian involvement’ is a sad state of affairs when we have aviation experts in this country who have retired from careers in many parts of the world, and are now capable of sharing their knowledge and experience to good effect.

There is already an Indian-managed flying school at Ratmalana catering to Indian students. Maybe the camel has already put its head in the tent, and only money will talk.

GUWAN SEEYA

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Opinion

Pledges to abolish executive presidency

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With the presidential elections around the corner, the abolition of the executive presidency has come up for discussion once again.

This time around, the proposal for abolishing the executive presidency has come from former President Chandrika B. Kumaratunga. She pledged to scrap it first when she ran for Presidency in 1994. But she did not fulfil her promise.

Former Presidents Mahinda Rajapaksa and Maithripala Sirisena are also now for scrapping the executive presidency.

Almost all the former Presidents came to power promising to scrap it but once in power they swept it under the carpet.

The Opposition parties claim they are for the abolition, but after the next presidential election. which, they say, they are confident of winning.

Mahinda has recently said it is preferable to abolish the executive presidency because he has already held it twice. However, he seems to have forgotten that he was greedy for power and he failed in his third attempt. For him and most other past Presidents, executive presidency is sour grapes.

They are now trying to have the executive presidency abolished in the hope that they will be able secure the premiership.

Ironically, Anura K Dissanayake, NPP leader and presidential candidate is against the abolition of the executive presidency as he is confident of winning the next presidential election.

So, all of them are in the same boat and one thing is clear; whoever becomes President will never have it abolished.

The campaign for scrapping the executive presidency will go in circles, forever.

Dr. P.A. Samaraweera 

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