AGRICULTURAL RESEARCH AND EXTENSION UNIT

Transcription

1 AGRICULTURAL RESEARCH AND EXTENSION UNIT (Food and Agricultural Research Council) HYDROPONIC commercialized FERTILIZERS in Mauritius r (Comparative study of the different hydroponic fertilizer formulations. available in Mauritius)

2 11.0 Introduction I Hydroponics can be defined as the science of growing plants in a medium, other than soil, using mixtures of the essential plant nutrient elements dissolved in water. The word hydroponics is derived from two Greek words: "hydro" (water) and "ponos " (labour). The plants that are grown in hydroponic are 'fed with a nutrient solution. The nutrient solution consists of water into which all the essential elements needed by the plants for their growth and development are dissolved The Hydroponic utrient Solution 1 Plant requires 16 essential elements for its growth and development. These are made up of the major elements (nitrogen, potassium, phosphorus, calcium, magnesi,ulphur) and also carbon, oxygen and hydrogen available in the form of water and carbon dioxide. The minor elements (iron, boron, manganese, copper, zinc, molybdenum, chlorine) are required in very little amount. These 13 major and minor elements are mixed in water to gi e the hydroponic nutrient solution. Research has been carried out to develop different formulations so that a specific amount of each element is used to prepare the nutrient solution. This eliminates any problems of toxicity (due to excess fertilizer) and deficiency (due to limited fertilizer). Two important components of hydroponic solution are the ph (acidity) and E.C. (Electrical Conductivity) ph: The ph value is a measure of the acidity or alkalinity and it ranges from a value of 1 to 14. ApH less than 7 indicates acidity; 7 is neutral and above 7 it is alkaline. The ph of the nutrient solution determines the availability to the plant roots of the various elements found in nutrient solution. Most plants prefer a ph level between 5.8 to 6.5 for optimum nutrient absorbtion. E.C.: Inorganic fertilizer dissolved in water and dissociates into individual electrically charged units called ions and these ions conduct electricity. The desired range of ErC. is generally betweenl.9 ms/cm to 2.3 ms/cm.

3 Hydroponic fertilizer is available or prepared as concentrated solution A and concentrated solution B. The purpose of preparing two separate solution A and B is to prevent mixing of element like calcium with phosphate or sulphate salts. Three types of fertilizer formulations are commercially available in Mauritius for use by hydroponic growers and these are: (a) Chemco Nutrient Solution A and Chemco Nutrient Solution B. (b) Chemco Granular Fertilizer known as Hydro Packs (A + B). (c) Individual compound fertilizers in the granular form which are used to prepare nutrient solution according to specific guidelines. PART! (i) Chemco Nutrient So SolutionB ion A and Chemco Nutrient r The hydroponic solution A and hydroponic solution Bare concentrated liquid feritilizer and are available in the following consignment. Fertilizer Available in Price of 1 L of Total Cost consignment A+ 1 LofB (Rs) of Hydroponic solution A and B 5L Rs Hydroponic solution A and B 25 L Rs Hydroponic solution A and B 200 L Rs To prepare the final diluted nutrient solution 1 L of concentrated nutrient solution A and 1 L of concentrated nutrient solution Bare mixed in 100 L of water. This solution will contain all the nutrients in the concentration given below at a ph of and E.C. of 2.3 ms/cm.

4 Element Concentration Nitrate Nitrogen 200ppmN Phosphorus 50ppm P Potassium 300 ppm K Calcium 180 ppm Ca Magnesium 50 ppmmg Sulphur 120ppm S Iron 3.0 ppm Fe Manganese 0.3 ppmmn Zinc 0.3 ppmzn Copper 0.1 ppm Cu Molybdenum 0.05 ppmmo Note: The same formulation is used for any vegetable crop throughout the whole crop cycle. (ii) Chemco Granular Fertilizer (Hydro PacksAand B) "- The hydro pack fertilizer:s ~re gran lar fertilizers which are available in three different formulations to cater for three different stages of plant growth. (see table below) Stage Formulation Price/Pack 1 Hydro pack 1 (A & B) Rs Hydro pack 2 (A & B) Rs Hydro pack 3 (A & B) Rs 1200 Note: The different stages of the crop cycle can be divided into: Stage 1- From transplantation of seedling to the development oftbird flower Stage 2- From appearance offourth flower up to the harvest of econd bunch offruits. Stage 3- After harvest of s cond bunch offruit to the end of erop cycle Each pack contains two separate products (A & B) in granular form and these have to be dissolved separately in 2 containers of70 litres of water each to give the concentrated nutrient solution stock. Each 70 litres of this stock solution of A and B needs to be further diluted to give the diluted nutrient solution. For its application, the final solution is prepared by diluting 1 L of A plus 1 L of B in 100 L of water. This solution ill contain all the nutrients in a well balanced formula essential for hydroponic culture as given below at a ph of and E.C of 2.3 ms/cm.

5 (iii) Individual compound fertilizers in the granular form Instead of purchasing the pre-mixed fertilizers, growers can prepare their own stock solutions using individual compound fertilizers following recommended guidelines. The amount and cost of individual compound fertilizers used In recommended formulation is given below. Fertilizer Available in Price/kg Total Price consignment (Rs) (Rs) of Microelements 20 L 1051L 2100 Calcium Nitrate 25 Kg Monopotassium Phosphate (Mkp) 25 Kg Magnesium Sulphate 50 Kg Potassium Sulphate 25 Kg Monoammonium Phosphate 25 Kg Potassium Nitrate 25 Kg

6 The nutrient solution stocks are prepared in two separate 50 L container (concentrated solution A and concentrated solution B). This prevents formation of insoluble precipitates of calcium phosphate and calcium sulphate. Each 50 litres solution of A and B is now in the concentrated form and need to be further diluted. For application to. plants, the nutrient solution is prepared by mixing 0.6 litres of solution A litres of solution B in 100 litres of water. The resulting nutrient solution should have an E.C. within the range of ms/cmanda ph within the range The individual compound fertilizers in the granular form are mixed according to three different formulations to cater for different stages of plant growth. These are listed below: Formulation for preparation of Hydroponic stock Solution A and Solution B: Container A (50Lof water) Container B (50Lof water) Stage 1 Stage 2 Stage 3 Fertilizer Salts Amount Amount Am unt (kg) (kg) (kg _ Potassium nitrate ~ -,--- Monoammonium phosphate Magnesium sulphate Potassium sulphate Monopotassium phosphate Potassium nitrate Calcium nitrate Microelements(kanieltra) 1.0 L 1.0 L 1.0 L r ote: The microelements (Kanieltra) used!in the prepar tion of the stock solution should consi t of the followingmicroelements; Microelements (Kanieltra) Concentration (% per pint) Boron 0.5 Copper 0.5 Iron 2 Manganese 0.5 Molybdenum 0.02 Zinc 0.5

7 PART 2 The amount of the different fertilizer formulations and their cost with respect to the crop and its crop cycle are given below: ote: In all the calculations, it has been assumed that 1 plant uses 1 litre of solution per day throughout the whole crop cycle. Crop: TOMATO (Crop cycle 6 months) (1256 plants) Stage 1= 1month; Stage 2 =2 months; Stage 3 = 3 months Chemco Nutrient Chemco Granular Individual compound Solution Fertilizer fertilizer formulation Fertilizer Amount Fertilizer Amount Fertilizer Amount (L) (No. of packs) Cone. Nutr Hydro Solution A oack I 6 Microelements 30L Hydro Cone. Nutr pack 2 12 Calcium Nitrate 330 kg Solution B Hydro 18 Monopotassium pack 3 phosphate 90 kg Total No. Magnesium of Hydro 36 sulphate oacks 120 kg Potassium sulphate 60k!! Monoammonium phosphate 6 kg Potassium nitrate 210 kg Total cost: I Rs 45,240 Rs 38,400 Rs

8 Crop: CUMCUMBER AND MELON (Crop cycle: 3 months) (1256 plants) Stage 1= 3 weeks; Stage 2 = 4 weeks; Stage 3 = 5 weeks Chemco Nutrient Chemco Granular Individual compound Solution Fertilizer fertilizer formulation Fertilizer Amount Fertilize Amount Fertilizer Amount (L) (No of acks Cone Nutr. IS L. Solution 6 A 165 kg Cone. Nutr. Solution B Magnesium sulphate 45 kg 60 kg Total Cost Potassium sui hate Monoammonium, hate Pota sium nitrate 30 kg 3 kg 105 kg Rs22,620 Rs19,600 Rs13,028 r Crop: SWEET PEPPER ( rop cycle: 5 months) (1256 plants) Stage 1= 1month; Stage 2 = 2 months; Stage 3 = 2 months Cbemco utrient Cbemco Granular Individual compound Solution Fertilizer fertilizer formulation Fertilizer Amount Fertilizer Amount Fertilizer Amount (L) (No of acks Cone, Nutr Hydro Solution A aek I 6 Cone Nutr Solution B Potassium nitrate 175 kg Total Cost Rs Rs Rs 21,713

9 Summary table of cost each commercial nutrient formulation with respect to specific crop Fertilizer Tomato Sweet Pepper Cucumber/ Melon (1256 plants) (1256 plants) (1256 plants) Chemco Nutrient Rs 45,420 Rs 37,700 Rs 22,620 Solution (A +B) Chemco Granular Rs 38,400 Rs 31,100 Rs 19,600 Ferti lizer(h ydropack A +B) Individual compound Rs 26,055 Rs 21,713 Rs 13,028 fertilizer formulation Pre-mixed fertilizer materials though easy to use, are relatively expensive compared to individual compound fertilizers. The premixed fertilizers leave little room for making changes in concentrations of individual n trients. r A comparison of the values for the cost of different commercialized nutrient solution shows that using the individual compound fertilizer formulation is the cheapest as compared to the pre-mixed fertilizers. However the only hassle is that the grower has to weigh individual fertilizer prior to preparing the concentrated stock solutions.

10 List of Hydroponic Fertiliser Suppliers 1..Mauritius Chemical Fertilizer Industry(CHEMCO) Chaussee Tromelin, Fort Georges PO Box 344, Port Louis Phone No.: Fax No: (Mr. Ajay Luximon) 2. Bonns Agribusiness Bonne- Terre Vacoas Phone No , Fax No: (Mr. Gobhurdun) 3. Best Agri Ltd. 13, Jacmin Street, Roches Brunes Phone / Fax No.: Mobile No.: (Mr. Ajagen Veerapen) 4. Greenworld Company Ltd. Solferino No.1, Vacoas Phone No.: Mobile No.: Fax No.: (Mr. Gunsham Boodram) Agricultural Research and Extension Unit St. Jean Road, Quatre Bornes Tel: Fax: areu@intnet.mu