Agriculture development towards nutritional security

by Prof. J.M.R.S.Bandara - Senior Professor of Agric. Biology and the Director, NCOA

The total population in Sri Lanka in 2030 would be 22.9 million, an increase of 19.27% from 19 million today. Food demand is expected to grow even faster as a result of increase in urbanization and rise in incomes (OECD-FAO, 2005). This natural growth alone demands a clear vision towards increase in food production, such as "Api Wawamu Rata Nagamu". However in Sri Lanka at present 22 percent of the children are underweight, with 4 percent classified as severely underweight.

In the DHS (Sri Lanka DHS, 2006/2007) study it was revealed that 25.3% of the Sri Lankan children at the age of 48-59 months of age are undernourished and 4.3% of the children in the same age group are severely undernourished. They also reported that the undernourished situation declines at a steady rate with the increase in mother's education implying that it is a question of food quality rather than food quantity. Sri Lanka is therefore faced with a problem of eliminating malnutrition and also meeting the ever increase in food demand.

This demand for food will in turn demand more land for crop production. Tilman (2001) predicts that to feed a world population of 9 billion with the current food production strategies would have to convert another one billion ha of natural habitat to crop land especially in the developing world where the population expands at a faster rate.

This amounts to threefold increase of inputs of Nitrogen, Phosphorous and pesticide use with two fold increase in irrigation water. Among the inputs water use would be extremely limiting because we are already using 70% of the fresh water available for agriculture.

Modern farming

National average yield of rice in Sri Lanka increased from around 2 t/ha the 1970's to 3.5 t/ha by the early 1980's. Since then it remained stagnant despite 95 percent of the rice extent being brought under improved cultivars. In addition to this, the per capita consumption of rice had increased from 95 kg/year to 100 kg/yr from 1999 to 2008. The increased use of agrochemical inputs and regular improvement of rice varieties (for that matter any crop variety) has failed to produce the quantity required to meet the needs of the population. The modern approach in rice farming has not been able to meet the demand completely for staple rice in Sri Lanka. Sri Lanka needs to increase the production to 4.1 mt/ha.

It is worth analyzing the food habits and the nature of rice varieties we had in the ancient Sri Lanka, where food security was ample using less fertilizer and agrochemical independent rice varieties.

It is obvious from the historical evidence that the farming system prevailing at ancient times especially during Rajarata Civilization was sustainable and met the needs of food security of the nation. Siriweera (2005) observed that the farmers of Rajarata then fed a very large population of Buddhist monks who did not participate in any production process. Present evidence from the ruins of "Bath Oruwa" at the temple premises at Mihintale supports his observation.

Siriweera (2005) reported that the yield of rice varieties in the 13th and 14th Century was eighty units per each unit sown. These varieties were never reported to be fertilized with any synthetic fertilizer though they were planted based on timely cultivation (Kal yal bala) farming calender (Bandara, 2007) that adopted three cultivation seasons namely Pita dada hasa (Maha), Akala Hasa (Yala) and Meda hasa (in between) as evident from Tonigala Rock Inscription of the 4th Century AD.

The present day farming system thus appears to fall short in meeting the demands of food in both in quantity and quality. It appears that the philosophy behind the application of technology involved in modern agriculture is to consider the nature as a competitor that need to be overcome! It is natural to overlook the friendlier aspects of the nature when the nature is considered to be a power to be overcome for higher achievements in farming.

However the interaction between farming system and ecosystem are complex. Most environmental problems are invariably linked with political, cultural, social and economical forces which are external to agriculture. Impact of this artificial competition created by the modern farming system has resulted in many detrimental effects on the environment as well as on the human health.

Modern Farming is the main widespread activity that influences the quality of water and the environment. The most obvious source of fresh water pollution is the addition of excessive untreated waste to water ways through the run-off from agricultural fields.

Many reservoirs of water in Sri Lanka are now contaminated with heavy metals, Persistent Organic Pollutants (POP) and nutrients that have an adverse effect on human health.

However it appears that we are yet naive about the potential threat expressed by the agriculture based pollutants on the human race. Extensive pesticide application in the environment has reduced the viability of human sperms and fertility has been reduced. Besides the low fertility, the young humans are the most affected.

In a study conducted in the Urology Unit of the Teaching Hospital, Kandy, Sri Lanka, it was observed that more than 53% of the bladder cancer patients were either farmers or farm occupants where chemicals are used as pesticides (Wickramarachchi, 2005). It was observed occurrence of pesticides namely Propanil (1.02 - 1.18 ppm) and Chlorpyriphos (1.45 - 6.77 ppm) in water samples collected from Meegalawa Wewa, in the dry zone of Sri Lanka, where irrigated agriculture is practised.

The presence of chlorpyriphos in reservoirs in Sri Lanka is a serious concern when the possibility of using these reservoirs as drinking water sources without adequate decontamination techniques. The gravity of such contaminants is of grave concern as it is a compound with known toxicity to the brain and nervous system.

Water pollution

As in the case of pesticides we are using more and more chemical fertilizer now, without any concerns to subsequent profitability of the yield gained or water pollution. The total amount of Urea fertilizer used by Sri Lankan rice farmers in 2004 was 220,000 metric tons compared to 193,000 metric tons in the year 2000. However, the returns per metric ton of Urea used is declining. Based on the total rice production in both Yala and Maha seasons of cultivation the paddy production per metric ton of Urea used is 14.82 in year 2000, where as in the year 2004 it is 11.94 (metric tons).

Nitrate pollution in Kalpitiya peninsula of Sri Lanka is a well-known example. The potential health implications of the contamination of drinking water by nitrates are primarily in connection with methaemoglobinaemia. The elevated nitrate levels are due to leaching of nitrogenous fertilizers from paddy land and intensively cultivated soils and a correlation between nitrate concentration and infant mortality rate has been suggested.

In the Kalpitiya peninsula, monitoring of irrigation wells showed a clear correlation of ground water quality with land use. Ground water within the intensively cultivated area typically had nitrate concentrations in the range of 10-15 mg 1-1 compared to 0.2 mg 1-1 within the non-cultivated lands.

Chronic kidney disease

Heavy metals are released to environment from a wide range of natural and anthropogenic sources. very often rate of addition of these heavy metals exceeds their natural process of removing as a result accumulates in the environment. Aquatic ecosystems are normally at the receiving end. Heavy metals are dangerous because they tend to bioaccumulate: i.e. increase in the concentration of a chemical in plant or animal over time, in comparison to that of environment.

Fertilizer usually contaminated during the manufacturing process results in impure fertilizer and adds many different types of heavy metals. Especially cadmium is a notorious addition to soils of crop fields through phosphate fertilizer (Klassen, 1996). Cadmium is toxic due to its chemical similarity to zinc an essential micronutrient for plants, animals and humans. Cadmium is bio-persistent and once absorbed by an organism, remains resident for many years (over decades for humans) although it is eventually excreted.

In Japan "Itai Itai disease due to cadmium toxicity was a problem caused by addition of cadmium to water by an industrial accident, resulting high level of cadmium in irrigation water of rice crops. Rice grain absorbed the cadmium which resulted in poisoning consumers resulted in kidney failure and death. Bandara et al., 2007 reported that the elevated dietary cadmium levels in rice and fresh water fish in farm lands under cascade irrigation systems in North Central Province in Sri Lanka is the main cause of Chronic Renal Failure prevalent in the area. In a study reported by the research team lead by Bandara reported that over 5,000 patients are under treatments for CRF in the region especially in Anuradhapura, Polonnaruwa and Medawachchiya region.

Organic farming

It is evident that the solution for most of the human health hazards that prevails due to contamination of food with man made toxins is to adopt traditional indigenous farming systems where little or no non biodegradable persistent organic pollutants are used. The strategy proposed by FAO is now well known as Organic farming. "Organic agriculture as a holistic production management system that avoids use of synthetic fertilizers, pesticides and genetically modified organisms, minimizes pollution of air, soil and water, and optimizes the health and productivity of interdependent communities of plants, animals and people" (FAO,2007). To provide clarity on the organic claim, organic agriculture is governed by detailed standards (IFOAM) and lists of allowed and prohibited substances. In addition, the organic community has adopted four overriding principles for organic agriculture.

1. Principle of Health, organic agriculture should sustain and enhance the health of soil, plant, animal and human as one and indivisible.

2. Principle of Ecology: organic agriculture should be based on living ecological systems and cycles, work with them, emulate them and help sustain them.

3 . Principle of Fairness: organic agriculture should build on relationships that ensure fairness with regard to the common environment and life opportunities.

4. Principle of Care: organic agriculture should be managed in a precautionary and responsible manner to protect the health and well being of current and future generations and the environment. If these parameters are practiced healthier and toxic chemical free food can be provided to all.

In the indigenous organic farming system no genetically modified crops are used. It is now well established that GMO would produce proteins that can cause allergies when consumed. The Ministry of Agriculture of the Government of Sri Lanka, has taken a very progressive step of declaring the organic farming as one of her strategies of crop production and has joined hands with the University of Peradeniya, Faculty of Agriculture in providing training in Organic farming and activities in the popularizing of Organic Farming in Sri Lanka.

Already a National Centre for Organic Agriculture for this purpose is established at the Postgraduate Institute of Agriculture at University of Peradeniya Centre has established a marketing facility in the net as "Velandapola.com" and has initiated a development of a model organic village.

Up to now centre has trained over 1,000 farmers and leader personnel in organic Agriculture. In Sri Lanka we could easily attain the standard expected by FAO and gain security in food supply with healthier food if we are to follow the traditional indigenous farming systems with the use of traditional varieties that does not depend on synthetic inputs.

In an experiment conducted by my research team at Aralaganwila in 2001 in order to compare the sustainability of indigenous organic farming system with modern farming significantly higher profit margin was obtained by the use of Nawa Kekulama a indigenous organic rice farming procedure.

It was also observed that when no clean weeding or cleaning of bunds was practised in organic farming the biological control of pests is encouraged. The indigenous farming systems that did not use any inorganic fertilizer or chemicals is eco-friendly and also conserved water as mulching was practised. The amount of water used by the Nawa Kekulama organic farming was 14,993.33 cubic metres per ha compared to 73,804 cubic metres per ha in modern farming. The water use efficiency in Nawa Kekulama was found to be 2.36 cubic metres per gram of dry matter produced in comparison to 5.147 cubic metres per gram of dry mater produced by modern farming. (Bandara, 2007) In terms of amount of carbohydrate we could produce per unit of water is more in organic farming. In a detailed study conducted by Ediriweera in 2006 with 52 Ecological farmers (Rajanganaya 16, Galnewa 12, Palugaswewa 4, Matale-Murutholuwa 10, and Matale-Pubbiliya 10) in comparison to 53 modern farmers (Rajanganaya 12, Galnewa 14, Palugaswewa 4, Murutholuwa 17 and Pubbiliya 6) it was found that the mean yield of rice by ecological farmers at Rajanganaya was 94 bushels compared to modern farmers mean value of 99 in Yala 2006.

We observed in 2007 that the ecological farmer has not only healthy non toxic food but had no shortages of a well balanced diet. He had plenty of vegetables to feed his family throughout the year. Modern farmer however had a food scarcity for 6 to 9 months of the year. It was also reported by Ediriweera et al, 2007 that the food security during past five years was good among 40 of the 51 ecological farmers and 11 were moderately secure only one farmer faced problems of food shortage. Whereas among 49 of the modern farmers, only 8 had good food security, 35 moderate and 6 were without any food.

Nutritional quality

We observed in our studies that the indigenous varieties of rice used in organic farming is of high nutritive value in comparison to the today's more popular wheat flour or even the improved rice varieties. Rath Suwendel, Kuruluthudu Wee, Kaluheenati and Rathel had higher levels of crude protein in decreasing order compared to samba (improved varieties).

Almost all indigenous varieties had significantly higher iron, zinc and fiber content. The most valuable information to modern city dweller in terms of food quality of indigenous rice is that the Suwendel grown organically had a very low glycemic index (35) compared to Rathukekulu (52) which is the recommended rice for diabetes patients. The GI of italian white rice is 102, wheat 80-99 and Glucose 100. The Glycemic Index is the measure of effect of carbohydrates on blood glucose level. Carbohydrates that breaks down rapidly during digestion releasing glucose rapidly into the blood stream have a high GI and vice versa. The need to add external input either for production (fertilizer and pesticides) or in processing and storage could be minimized using organic farming strategies which are mostly indigenous technology. The consumption pattern need to be changes to accommodate healthier food habits with less process food involved in the diet, to reduce health risk especially on diabetes. An organised ecological farming system both for food and horticultural crops in the homestead will undoubtedly improve the food security of Sri Lanka.

Agricultural development for food security in a country never meant an ample supply of carbohydrate alone. The main objective is a healthier nation. This could be achieved only through a balanced nutritious diet that is produced at a very affordable cost. The objective of the many programs of the Ministry of Agriculture Development and Agrarian Services, such as the Api Wawamu Rata Nagamu, Govi Sathiya and World Food Day programs are to create awareness of this very useful concept of food grown to meet the nutrition need of the present and future population of the island.

The newest approach by the Ministry in linking up with the Universities to harness the resources available is and excellent step in achieving these objectives. It is very well understood that we are unable to live on the pleasure derived by the mere mention of our past glory and achievement of our ancient agricultural civilization such as Rajarata civilization. We need to practise the concept of then nation to have a healthier and wealthier nation.