Economic and social benefits of the agricultural sector, which includes cultivation of food crops and plantation crops, are well known to most of us. The value of the paddy and other food crops produced during a year is around Rs. 300 billion and we earned a similar amount in foreign exchange by exporting tea and other planation crops. Fertilisers and pesticides play an important role in crop production. However, the importation of chemical fertilisers, pesticides and herbicides was banned by a Cabinet Memorandum dated April 27, although these are not locally available in adequate amounts. As a result, inorganic fertilisers such as urea, Triple superphosphate, Muriate of Potash and other agrochemicals (insecticides, fungicides, etc.) became scarce. Agriculture Ministry in the meantime, promoted manufacture of organic fertilisers but they were unable to get sufficient amounts of organic fertilisers manufactured mainly because raw-material necessary for production of adequate amounts of organic fertilisers is not available locally. Thousands of farmers all over the country started to protest demanding that appropriate fertilisers and pesticides are made available. They have prepared the lands to cultivate paddy for the current Maha season but they are yet to start cultivating as they are not sure ofthe availability of appropriate fertilisers. Non availability of suitable fertilisers at correct times and appropriate pesticides is causing immense problems not only to paddy farmers but also among those who cultivate other food crops, horticultural and floricultural crops.

Probably the Finance Minister, having realised the utter foolishness of banning the import of inorganic fertilisers and synthetic pesticides lifted the ban and issued a gazette notification on 3 August re-authorising the import of several types of chemical fertilisers to be used in the Maha season. Ministry of Agriculture (MOA) realising the need to use inorganic fertilisers got down 30,000 of tons of potassium chloride. Although the MOA says that it is organic, to satisfy some, it is Muriate of Potash which is chemically potassium chloride (KCl) extracted from deposits of a mineral Sylvinite found in several countries. It does not matter whether it is called organic or inorganic as long it supplies potassium to crops

Perhaps because the MOA realised that there would be not enough organic fertilisers for the Maha season, Sri Lanka’s two state fertilizer companies signed an agreement with a Chinese fertilizer supplier to supply 96,000 MT of organic fertilizer (OF) in granular form containing 10 per cent of Nitrogen . According to National Plant Quarantine Service OF to be imported contain some pathogenic bacteria such as Bacillus and Erwinia. Hence, the shipment of the China-manufactured organic fertilizer was halted and the ship carrying the OF was supposed to have turned back.

As Sri Lanka is facing a severe shortage of both inorganic and organic fertilisers, after the import of the former was banned and the shipment of OF from China, was halted, MOA went ahead with the import of 3.1 million litres of nano- urea , a liquid fertiliser from Indian Farmers Fertiliser Cooperative Ltd (IFFCO) . In their official website, IFFCO has indicated that this Nano-urea fertiliser should be applied only as a top dressing along with a reduced rate of urea, According to all research reports on this liquid fertiliser, Nano-urea is a supplementary source of Nitrogen.

According to a web site https://patents.google.com/patent/CN1269774C/en Nano Urea comprises 0.01 to 5 wt% of quinhydrone, 0.01 to 10 wt% of calcium cyanamide in addition to urea.. There were some who were of the view that Chronic Kidney Disease ( CKDU) is caused by fertilisers. This is one of the reasons to justify banning of inorganic fertilisers and synthetic pesticides. Whether nano urea will cause similar effects is not known. Nano particles are of minute size . In general, nearly 100 kg of nitrogen is taken up by the paddy crop yielding 4-5 tons of grains per hectare. Accordingly, Nano-Urea should be applied at a rate of 1,250 liters per hectare if it is the only source of nitrogen added to the crop. Nano- urea need to be sprayed to the foliage and it is possible that it could have a disastrous effect on the living organisms including human beings, which the health authorities need to give serious consideration. Nano products are new to the environment and not enough research has been conducted on the long-term effects of Nano particles on animal health and environment. There are no recommendations on the amounts, and frequency of Nano Urea to be applied to different crops . Many Farmers are refusing to apply nano urea as they have not being made aware of the appropriate recommendations which should not be made in an ad-hoc manner without conducting any field investigations.

Considering the cost of the fertilizer and labour cost for application, the use of foliar fertilisers in a crop like paddy, is expensive and will increase the cost of production. Any fertiliser imported to the country needs to be tested following the accepted protocols prior to giving approval for importation and after the shipment has arrived in order to assure quality and to avoid any negative impacts. It is not known whether such tests were carried out before Nano-Urea was brought to the country.

Dr. C.S. Weeraratna,

csweera@sltnet.lk