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Frequently Asked Questions for ENGROZARAI.COM

 General

 Q. Why do crops need fertilizers?
A. Crop need 16 different nutrient elements for their growth and fruit, fiber or grain production. With the introduction of high yielding crops and increased cropping intensity, soils are becoming deficient in these nutrient elements with each passing day. So to make the deficiency of nutrient(s), farmers have to apply chemical fertilizers.

Q. What are micronutrients?
A. The nutrients required by crops in relatively large quantities are called major or macro nutrients and the nutrients required in smaller quantities are called micronutrient elements. But, both groups of nutrients are equally important for crop growth and yield.

Q. What bases are used for recommending fertilizer rates for various crops?
A. Fertilizer recommendations are based on two factors: i) nutrient requirement of a crop and ii) fertility level of the soil. Greater the requirement of a crop for nutrients, greater will be the quantity of fertilizer required and lower the fertility level of a soil, higher quantity of fertilizer will be needed. Generalized fertilizer recommendations are based on average crop requirements and average soil fertility levels. Specified recommendations can be made by considering soil test values and yield targets in mind.

Q. There are different kinds of fertilizers, some of which are costly and rare. Can one kind of fertilizer be replaced with another?
A. Fertilizers can be classified on the basis of nutrient compositions or nutrient proportions. Fertilizers with same nutrients can replace each other keeping in mind the total quantity of the nutrients.

Q. What is a fertilizer grade?
A. Fertilizer grades are the numeric values printed of fertilizer bags or packets in the sequence of percentage by weight of N, P2O5 and K2O, unless otherwise mentioned. A grade of 18-46-0 therefore would mean that the fertilizer material contains 18% by weight of N, and 46% by weight of P2O5, while there is no K2O in it. Similarly, a fertilizer grade of 0-0-60 means that the material contains 60% by weight of K2O while N and P are absent in it.

Q. Why don’t we apply all N as basal dose like P and K?
A. Phosphorus and K are minerals and react with soil and form such chemical compounds which maintain certain level of these nutrients in plant available form throughout growth period of a crop. Growing plant fulfills his requirement from these fertilizer-soil reaction products. Nitrogen, on the other hand, remains largely non-reactive with soil constituents and its soil levels do not increase after application of nitrogenous fertilizers. It is, therefore, subject to instant losses such as leaching with irrigation water and or its volatilization as a gas. It is, therefore, supplied in splits so as to keep its losses under control and ensure its maximum possible utilization by the growing crop.

Q. If one could not apply P or K fertilizers at the time of sowing, can he apply these fertilizers as top dressing?
A. The idea of applying P and K as basal fertilizers is to ensure their incorporation in soils so that they remain available to crop roots. If these fertilizers are applied as top dressing like urea, there are chances of their fixation by top soils and their unavailability to crop roots. Secondly, the major function of P is to support root growth. If these fertilizers are applied later on standing crops, their benefit to crops may not be as high as when applied as basal dose. However, if by any case they are to be applied later in the season, these should be applied as early as possible and in such a way that they reach nearest to the roots: During earthing up in case of sugarcane, at hoeing in case of vegetables etc. Their broadcasting on standing crop should be avoided.

Q. Can Zinc be applied as a basal fertilizer?
A. There are some reports about Zn reacting with P. Due to low solubility of resultant Zinc Phosphate, there is chance of low availability of either of the two. At the same time, there is enough evidence to believe that both P and Zn are released by Zinc Phosphate at rates higher than those required by plants. The story of Zn-P interaction is a continuous debate in scientific circles. A safe approach, therefore, is to avoid Zn application as a basal fertilizer.

Q. What is pH? What is the significance of soil pH?
A. pH of a system determines its reaction in terms of acidity or basicity. It is measured on a scale from 1 to 14, with 7 as the neutral point. Its increase from neutral point makes the system basic, the magnitude of which increases with increase in pH value. A system of pH 11 is, therefore, more basic compared to a system with pH 8. On the other hand, decrease in its value from neutral point means an increase in acidity level. A system at pH 5, therefore, is less acidic than at pH 3.

 Availability of most nutrients depends upon pH of the soils. This is because plants show favor for certain ionic species of essential nutrients over others. The most favorite species are found in the pH range of 5.5 to 6.5. The availability of both added and native nutrients are highest at this pH range. Deviation of pH from this range on either side causes decrease in availability of the nutrients to plants. Phosphorus is the most typical example of such a behavior.

Q. What generally is the pH of our soils? Can it be changed?
A. pH of soils is a chemical property, which is genetically determined, therefore not easily changeable. pH of our soils is in the basic range (more than 7) due to the predominant presence of basic cations like Ca, Mg, Na etc. These cations are accumulated in our soils due to low rainfall that results in net upward movement of water. In areas of high rainfall, these basic cations are washed down by rain water and soil is left with acidic cations such as Al, H etc. Soils of high rain fall areas are, therefore, acidic in nature.

Although pH of a soil can not be permanently changed, its impact can be diluted through cultural practices. pH of our soils can be brought and maintained closer to neutral point by building up its organic matter through addition of farm yard manure or by growing green mannuring crops etc.

Q. What then is the advantage of Zorawar over DAP?
A. To answer this question, we need to understand P-dynamics in soils. The solubility and hence plant-availability of both added and native P is controlled by the presence and magnitude of free calcium carbonate in calcareous soils like ours. Free Ca reacts with P and forms a range of Ca-P compounds with varied levels of water solubility. These compounds are called as reaction products. At least 56 reaction products have been identified as a result of P addition in calcareous soils. The solubility of reaction products determines the availability of P to plants.

 Research has produced enough evidence to believe that the nature of reaction products formed by the addition of DAP to calcareous soil is different from those formed by the addition of Zorawar to a calcareous soils. The solubility of Zorawar reaction products is higher than DAP reaction products. This phenomenon gives Zorawar an edge in calcareous soils over DAP. Research, however, is needed to be rectified this phenomenon under our local conditions.       

Q. If balanced amounts of N, P and K have been applied, micronutrient application may not be required?
A. On the contrary, balanced application of N, P and K can only yield required results if crop is not facing micronutrient deficiency. To get maximum benefit from balanced application of macronutrients, optimum availability of micronutrients to plants must be ensured.
      
 

Q. What is the advantage of Zarkhez on potato yield?
A. Balanced nutrient application ensures improvement in crop yield and quality, and maintenance of soil fertility on sustainable basis. Zarkhez increases tuber size and uniformity. It reduces the blackening the heart of potato. Zarkhez also increases keeping quality and shelf life of potato. Application of Zarkhez also increases the crop resistance against diseases.

Q. When compared with other fertilizers, Zarkhez is costly on nutrient basis. Why should I spend more?
A. No straight fertilizer provides all the three major nutrients in a balanced ratio. Straight fertilizers generally have one or two nutrients, while Zarkhez provides three major nutrient elements. Due to the inclusion of third nutrient element, its cost will be definitely higher. But, the value it gives to the farmer in form of increase in quality and yield of crops, it not really a costly product.

Q. Can we split Zarkhez application on Potato?
A. Not preferably. It is a short duration crop and it needs heavy nutrient supply at a very fast pace. So its recommended dose @ 7 bags per acre should be applied at the time of sowing.

Q. Potato growers traditionally apply heavy amounts of FYM. What will be its impact on Zarkhez recommended dosage?
A. Major function of FYM (farm yard manure) is to improve soil physical conditions (especially it increases soil water holding capacity and makes soil more porous). No reduction should be made in fertilizers to be applied to the crop as FYM have very little quantities of nutrients required by crops. FYM helps in increasing efficiency of applied fertilizers compared with soils where same amount of fertilizers is added without manners.

Q. What is the pH of Zarkhez green, what impact will it have on soil health?
pH of Zarkhez (Green) is neutral to slightly acidic. It will help in more availability of P to plant roots due to low pH in micro-climate near plant roots. 
 

Q. What is the advantage of Zarkhez on sugarcane yield?
A. Balanced nutrient application ensures improvement in crop yield and quality, and maintenance of soil fertility on sustainable basis. Zarkhez increases number of cane tillers per plant, cane weight and sucrose content. It reduces lodging of sugarcane crop and increases resistance against diseases. Its increases resistance against water shortages and improves better utilization of available water to the crop.

Q. When compared with other fertilizers, Zarkhez is costly on nutrient basis. Why should I spend more?
A. No straight fertilizer provides all the three major nutrients in a balanced ratio. Straight fertilizers generally have one or two nutrients, while Zarkhez provides three major nutrient elements. Due to the inclusion of third nutrient element, its cost will be definitely higher. But, the value it gives to the farmer in form of increase in quality and yield of crops, it not really a costly product.

Q. What is the advantage of Zarkhez on vegetables yield?
A. Balanced nutrient application ensures improvement in crop yield and quality, and maintenance of soil fertility on sustainable basis. Zarkhez makes skin of vegetables shiny, make attractive color and bigger size. Zarkhez increases shelf life of vegetables and improve taste.

 Q. What is proper application time of Zarkhez in onion?
A. At the time of sowing @ 3 bags per acre and after one month @ 2 bags per acre. 
 

Q. What is the advantage of Zarkhez on mango fruit?
A. Balanced nutrient application ensures improvement in crop yield and quality, and maintenance of soil fertility on sustainable basis. Zarkhez increases sweetness in mangoes, gives shining skins and fruits of uniform size with increased weight and size. It reduces lodging of sugarcane crop and increases resistance against diseases. Zarkhez increases shelf life of fruits for a week so.

Q. What is the advantage of Zarkhez on banana fruit?
A. Balanced nutrient application ensures improvement in crop yield and quality, and maintenance of soil fertility on sustainable basis. Zarkhez increases number and weight of fingers in banana bunch. It increases sweetness and shelf life of banana for a week so.

Q. What is proper application time of Zarkhez in mango?
A. In the months of Feb / March and Sep /Oct @ 3 kg per plant.

Q. What is proper application time of Zarkhez in banana?
A. Start application in month of March @ 3 bags per acre and in the months of April to Oct @ 3 bags per acre.

Q. When compared with other fertilizers, Zarkhez is costly on nutrient basis. Why should I spend more?
A. No straight fertilizer provides all the three major nutrients in a balanced ratio. Straight fertilizers generally have one or two nutrients, while Zarkhez provides three major nutrient elements. Due to the inclusion of third nutrient element, its cost will be definitely higher. But, the value it gives to the farmer in form of increase in quality and yield of crops, it not really a costly product.

Q. Mango growers traditionally apply FYM on mango. Do they need Zarkhez application in addition to FYM?
A. Major function of FYM is to improve soil physical conditions (especially it increases soil water holding capacity and makes soil more porous). No reduction should be made in fertilizers to be applied to the crop as FYM have very little quantities of nutrients required by crops. FYM helps in increasing efficiency of applied fertilizers compared with soils where same amount of fertilizers is added without manners. Application of FYM alone cannot provide the nutrients required by a mango orchard.

 

Q. What is the process of chelation?
Chelation is a naturally occurring or a synthetically fabricated process whereby a metal ion interacts with an organic compound to form a complex ring structure, which makes the metal ion unavailable for other reactants in the system.

Example: When iron (Fe) is applied to soil, it reacts with phosphate and is precipitated as iron phosphate – hence becomes unavailable for plant uptake. If Fe is reacted with certain organic acids before applying to soil, it forms a complex and becomes unavailable for phosphate present in soil. This process is called ‘chelation’.

Q. What is a ‘chelate’?
The word ‘chelate’ is derived from the Greek word ‘chel’ meaning a crab’s claw. Chemically, a chelate is a compound formed by complexing of cations with organic compounds, which results in the formation of a ring like structure in which the cation takes the core position while two or more molecule of the organic compound surround the cation from all sides like something gripped by a crab in its claw.

Q. What is a ‘chelating agent’?
A ‘chelating agent’ is an organic compound that can bind a metal cation such that the binding is not too strong that it can not be released even in the plant metabolic system, or too week to keep it secure from active soil constituents. Most commonly used chelating agent is ethylene diamine tetra acetate (EDTA), which is used to chelate Fe, Zn, Cu, and Mn. For high pH soils, diamine tri-phenyle penta acetate (DTPA) is preferred chelating agent but is about 5 times more expensive than EDTA. Sometimes a combination is also used as chelating agents. For example, Zn may be chelated with a EDTA-Citric acid mixture, in which case Citric acid is a cheaper chemical but a week chelating agent. In such case the efficiency of chelated fertilizer depends upon the ratio of various chemicals used as chelating agents.   

Q. What are the advantages of chelated micronutrients over their mineral counterparts?

• A mineral nutrient when applied to soil is hydrolyzed (broken down) to its cation, which is highly reactive and exposed to other active soil constituents for chemical reactions. Its reaction with other soil constituents may make it unavailable for plant uptake. In chelated form, however, it acts as an inert material in the soil, and is taken up by the plant as such. The research has revealed that agronomic efficiency of chelated micronutrients is about 3 times higher than in mineral form. The chelating agents of the metal ions will protect the chelated ions from unfavorable chemical reactions and hence increase the availability of these ions to plants.  One example is iron in high pH soil.  In high pH soil, iron will react with hydroxyl group (OH-) to form insoluble ferric hydroxide [Fe(OH)3] which is not available to plants. Chelation will prevent this reaction from happening and hence render iron available to plants.
   
• Metal ions in chelated form are more stable than the free ions, hence less possibility of the loss of nutrients through leaching.
   
• In case of foliar application also, chelated micronutrients have advantage in that they can easily penetrate the waxy coating on plant leaves, which is there to prevent leaves from drying. In ionic form, however, nutrients may face difficulty in entering the leaves due to this waxy coating.

Q. Why chelates are not popular despite their advantages, and mineral form remains predominant form for micronutrient fertilizers world over?
The process of chelation and chelating agents are very expensive, which makes chelated micronutrients a costly option. That is why; chelated micronutrients are only used on high value crops, sporting turfs, greenhouse crops etc world over and their use on field crops is not economical.

 For example, two molecules of EDTA are required to chelate one ion of Zn. In industrial terms it means that 400g EDTA would be required to chelate 65g Zn, or 240g EDTA would chelate 65g Zn at 60% degree of chelation. For 1 Liter of liquid chelated Zn fertilizer having 10% Zn, 100g Zn needs to be chelated. At 60% degree of chelation, 400g EDTA is required for this reaction, which would cost around Rs. 300 from local market (that too if commercial grade is purchased in bulk). Including the cost of other raw material and processing/packing etc., 1 Liter 10% Zn-EDTA can not be sold in the market at a price less than Rs. 500 (at cost price without margin for the importer / manufacturer).

Q. How liquid fertilizers containing chelated Zn are sold so cheap in our markets.
Because of the absence of any prescribed standards for chelated micronutrients in the country, some Zn-fertilizer manufacturers are taking undue advantage and are selling non-chelated or poorly chelated products with the claim of ‘chelated products’. Currently, the products are tested/assessed on the basis of their total Zn content only, and no protocol is available for assessing chelation/non-chelation of a product and/or degree of chelation in any given product.

 Remember that there is a difference between a properly chelated micronutrient and a micronutrient in which some amount of chelating agent is mixed. A poorly chelated micronutrient will behave in soil just like a mineral fertilizer and will not enjoy the benefits of chelation.  Therefore, the companies selling cheap chelated micronutrients are basically trying to cheat the farmers.