Cornell University Retired Director General of Agriculture
Consequently, the water in major reservoirs has also been conserved for the next Yala cultivation season. Solar radiation during the Maha season has been good for the crop photosynthesis. When the water and sunshine combination is ideal, we believe that the country becomes rich in rice to feed 20 million mouths, two to three times a day. In fact, the rice harvest just gathered is the highest ever obtained during a Maha season. (See Table).
Given the sunshine during Yala season, the country should produce another bumper rice crop because water is already available in the major irrigation systems. However, is it only water and light that arrive from the heavens that determine crop performance?
How significant are biotic factors in crop production? The purpose of this write-up is to focus on some of the biotic factors and their combinations which have collectively contributed to the realized rice bumper crop. Understanding their significance is sacrosanct to further scientific thinking to achieve even higher levels of crop performance.
Soil and plant nutrient environment
Soil as a living substratum for rice cultivation provides anchor, nutrients (macro and micro), microorganisms and growth promoting hormones. Their right combination is needed to provide the ideal situation for optimum plant growth. Age-old technology of incorporating organic matter into the soil has been neglected with the importation of inorganic fertilizer. It was believed, (and made to believe) that inorganic fertilizer could fully cater to plant nutritional requirements. The notion sidelined the fact that soil is very much a living entity and must be cared for to help raise healthy crops. After decades of using only inorganic fertilizer, it became apparent to rice scientists that the expected yields with new rice varieties would not be forthcoming.
Genetic improvement of rice varieties by itself is inadequate to meet the challenges in the biological environment. The ‘living’ soil must be helped to develop the capacity to deliver what the rice plant needs. With the "new" thinking, the Department of Agriculture embarked on a programme to re-educate the farmers on the virtues of using a combination of organic material with inorganic fertilizer. Whatever organic matter the farmers could access would be incorporated into the soil at the time of land preparation. Green leaves, cattle manure, poultry dung and half-burnt rice husk were prescribed to be compulsory additives to the soil at land preparation. The yields obtained were most encouraging to the farmers. Rice farmers who obtain the highest yields ever in this country report over 200 bushels of grain per acre (10 tons per hectare) with the combination of organic coupled with inorganic nutrient technology.
Rice varieties and extents covered
The Department of Agriculture is the sole organisation responsible for rice breeding. Since independence, the department has officially released over 50 varieties of rice at the rate of one variety per year. The public would recall the impact of variety H4 bred by Dr. Hector Weeraratne at the Central Rice Breeding Station, Bathalagoda. It revolutionized rice cultivation in the country and replaced almost 90 per cent of traditional rice varieties grown by farmers. The key features of the variety were the high yields (4 tons per hectare compared to 2 tons per hectare with traditional varieties and excellent palatability. Similar dedicated breeders of the caliber of Dr. Dharmawansha Sendhira and Dr. M. P. Dhanapala and their disciples continued the rice varietal improvement programmes which resulted in varieties that could compete with the best in the world. The yield potential of some of the varieties exceed 10 tons per hectare. Sri Lankan farmers sow over 95 per cent of the asweddumised extent with the improved rice varieties, thanks to the agricultural extension scientists and their programs, enabling farmers to realize high yields. The national rice grain yield level is approximately 4 tons per hectare because of the drag down in the wet zone districts. Yet, Sri Lanka is above India and Thailand in per hectare rice yield levels. The average grain yield in the high potential dry zone districts is around 6 tons per hectare.
Use of quality rice seed
Improved rice varieties must find their way to the farmers’ field without adulteration or decline in the genetic make-up. Similarly, the seeds used by farmers must be high in germination and vigour, have no weeds or contaminants. To ensure these quality attributes to the farmer, the Department of Agriculture has been implementing scientific quality assurance systems from production fields to retail points. Almost 20 percent of the rice seed sown in this country has been produced using this quality assured system. Private and state sector seed production ventures have developed mutually complementing collaborations which have during the past six years blossomed into a vibrant seed supply organizations seldom seen in other countries. The 20 per cent coverage of the extent sown with quality seed today is no mean achievement because it was only 4 per cent coverage in 1999. Government support to launch the project entitled, "Basic Seed Supply Programme" since 1999 and the dedication of the officers of the Seed Certification Service and the government farms network of the Department of Agriculture are commendable.
Quality seed paddy is produced mostly at village level in the dry zone areas. The product undergoes rigorous quality verification at field level and in the Seed Testing Laboratories of the Department of Agriculture before reaching the farmer. It is scientifically proven that crop yields increase by at least 20 per cent by mere use of quality seed alone. Most progressive farmers are aware of this fact and seek quality assured seed every season. In Ampara district where rice is a highly paying crop because of high yields, it is reported that about 60 per cent of the farmers use quality assured rice seed.
The seed programme of the Department of Agriculture sets standards for the industry to follow. Therefore, farmers have the fullest confidence in the seeds carrying the labels of the DOA. Private seed producers who earn the DOA label after following the rules and regulations of the DOA use it as a marketing tool for maximum financial benefit as the label signifies premium quality sought by farmers.
Environment friendly technologies
Rice when grown repeatedly on the same land invites a host of pests, especially in our tropical environment.
Therefore, pesticide use has been increasing up to recent times. However, it is now common knowledge that the excessive or unwanted use of pesticides actually increases pest incidence because of the elimination of the beneficial insects living alongside the pests in the rice growing environment. Therefore, the Plant Protection Service of the Department of Agriculture has launched the Integrated Pest Management (IPM) system during the past two decades with great success and farmer acceptance. It advocates use of pesticides only in the event that a specific prevalent pest population becomes economically threatening. It not only saved costs of pesticides, and spraying costs but saved the environment and the rice consumer as well.
Rice production also increased in the IPM areas because of the build up of beneficial insects and natural elimination of pests. The IPM program continues to be improved and expanded to cover more land in the country with support from the central and provincial extension systems.
Simultaneously, the pesticides that are allowed to be imported are restricted to the safest available through prior informed concept (PIC) practiced between the exporting and importing countries. Sri Lanka is no longer the dumping grounds for pesticides.
The Department of Agriculture has built the laws and regulations to keep away the "dirty" pesticides from our environment for a long period. The return of the flocks of storks, reptiles, crabs, etc., to our paddy field landscapes in recent times are reassuring indicators of the environmentally safe pesticides and the success of the IPM strategies.
Silent scientists
Most of the above-mentioned programmes are operated by scientists without fanfare and publicity as technical officers normally do all over the world. Therefore, people generally are unaware of the scientists’ dedication or contributions to national causes. However, in this case it is a sacred effort for ensuring national food security, and it is worthwhile to bring about some publicity and appreciation of the programmes and our scientists, who use the weather factors, over which we have no control, to the maximum benefit of the rice eating nation. Let this be a tribute to their efforts and dedication.
