More research needed into the current issues affecting the rice industry

Oct 22, 2008 Letters

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Dear Editor,
I respond to Mr. Ramdular Singh’s letter SN dated 19th October 2008 titled, “Farmers need TSP fertilizer”.
Fertilizers are a basic component of efficient and sustainable crop production. In crops such as rice, fertilizers can be the largest variable cost production component.
During the past years, fertilizer prices have risen dramatically. Prices have increased due to increased energy costs for production, especially natural gas, increased transportation costs, and increased demand.
The major phosphate (P) fertilizers sources that are currently used in Guyana are diammonium phosphate (DAP) and triple super phosphate (TSP).
These P fertilizers are all produced from rock phosphate. Rock phosphate is very insoluble and must be treated with acid to make the water soluble fertilizers. Phosphate fertilizer production process involves treating with rock phosphate with sulfuric acid to make ÅggreenÅh or Ågwet-processÅh phosphoric acid. This agricultural grade phosphoric acid is then utilised to make the phosphorus fertilizers that are used in agricultural applications.
Diammonium phosphate fertilizer are made by reacting anhydrous ammonia (NH3) with phosphoric acid, these are 100% water soluble, and have analysis and properties: DAP ((18-46-0) NPK) — Dry granular. These are the most widely used P fertilizers in USA and the world at this time.
Triple super phosphate fertilizer is made by reacting rock phosphate with phosphoric acid to produce a P fertilizer with an analysis of 0-46-0. This is a dry granular fertilizer utilized in bulk blending for making zero N grade complete fertilizers. This fertilizer also serves as the P source for ammonization plants where granular N-P-K fertilizers that contain all nutrients in each granule are manufactured.
World fertilizer demand is predicted to increase by approximately 2.7% per year and phosphorus fertilizer supplies would have been adequate, however, prices have increased due to increased costs for anhydrous ammonia in the manufacturing process for DAP and TSP.
Also transportation costs have increased due to higher fuel costs. Guyanese growers will have to pay world market prices as the companies that mine rock phosphate and manufacture finished fertilizers are international in scope.
Now with that background, I come to Mr. Singh’s letter: In his first line he mentioned that “we cannot produce rice without TSP fertilizer”. I would not agree with that since rice is, and has successfully been grown in Guyana with P fertilizer other than TSP.
In his second line he mentioned that “the RPA is bringing cheap fertilizer”; there is nothing like “cheap” fertilizer. I guess what the RPA is trying to do is to import the fertilizer in bulk and just take an operational cost, thus making the fertilizer available at a lower rate than the commercial dealers. This should be commended rather than condemned since the RPA efforts are to make the industry competitive as possible.
In the same line he continued to say that the “Government does not have people to advise them”. This is not true since the Guyana Rice Development Board (GRDB) has its Research Station at Burma Mahaicony that specifically deals with rice research and has a specific section that deals with Nutrient Management which is headed by Qualified and Experienced personnel.
In Mr. Singh’s second paragraph he mentioned that TSP has to be used every crop; this is not entirely true since P is not leached or lost from the soil so easily as N and what every P is present in the soil should be available to the plant for its use. However, the availability of P depends on many factors and thus the management applied by the farmer and the soil status will determine the available P to the plant. It is well established that flooding increases the availability of soil P to rice (Oryza sativa L.) as well as soil aggregation, pH and micronutrient availability and other factors.
Mr. Singh went on to mention that the “RPA does not know anything about rice”. The RPA has been established since the early 70s and have since then been working for the cause of the Guyanese rice farmers.
The RPA by its constitution is made up of mainly rice farmers from all parts of the country and thus, its policy and activities are governed by these farmers themselves.
So it will be an insult to these farmers to say that the RPA does not know anything about rice; it is like saying rice farmers don’t know what they are doing.
Notwithstanding all that I have said, I think that more research has to be done in the area of Nutrient Management with specific reference to “Site Specific Nutrient Management”, laboratory testing of rice soils, and sensitization of farmers to current issues affecting the rice industry.
Bissasar Chintamanie
IIT, Roorkee, (UK)
India

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