Interesting Dr. Bijay Singh ji. Nitrogen is the only element which is being discussed for long and it will be discussed in the same context in future also. The dynamics it follows is unique. Though there are 15N studies yet, it reflects that inspite of adequate N to soil is applied, 50%around comes from the soil pool. More the capacity of the soils to convert the applied fertilizer N into the body tissues of microbes and subsequent releases to the medium when solution N reduces and less chances to convert to very slow N, fertilizer use efficiency will be more and environmental losses will be less.

I think nitrogen is very important element on earth i.e. 78% in air and neutral in nature, which is a resistant barrier for oxygen otherwise all earth is in burning stage. You question is at right time when nitrogen in the soil is deficient due to acidic effect of urea which it make in the soil. Second the microorganism status in the soil has been disturbed due to over doses of the nitrogeneous and other fertilizers synthesized chemically. The rhizobium leguminoserum bacteria are deficient in soils hence we have to ask the farmers to use bioferilizers on seeds. The efficiency of the nitrogenous fertilizers can be enhanced by fertigation (using nitrogenous fertilizers in drip irrigation system). I think the future results are based on how we are educating the farmers. Please visit at www.krishigyanpatrika.in

These are major challenges of how to simultaneously ensure global food security along with high nitrogen use efficiency (NUE) and protect the environment have received increasing attention. However, the prevailing agricultural pattern still considers high yield and reducing environmental impacts to be in conflict with one another. (i) To develop efficient root-zone nutrient management to significantly increase NUE, (ii) integrated nutrient management to increase both yield and NUE by 15%—20% and (iii) integrated soil-crop system management (crop rotation with legumes or pulses) to increase yield and NUE by 30%—50% simultaneously. These advances can thus be considered an effective agricultural paradigm to ensure food security while increasing NUE and improving environmental quality.

No way. Everything has norms and ratios, depending on the type of soil and the types of crops grown and a number of other soil characteristics

You cannot use a unform code for everry situation - as mentioned above, soil formation and nutrient characteristics depend basically on geology and subsequent abuse. One has to get the soil test done before deciding on the nitrogen requirement. In fact we have already converted vast areas of forest into agricultural land to meet the food security. Any further damage to the remaining forests is not advisable. What we could concentrate is to strengthen the existing to ensure better yield with quality seeds.

May I add to the above expressed views of Zakir Aliyev and A K Shyam that indeed some studies/ reports have shown that crop yields under N-fertilization have over time required double the amounts of N-fertilizers to attain the same levels of crop yields. Without doubt, the negative effects of chemical fertilization on soil health and biotic life cannot be over emphasized. In fact, of recent is the concern of these chemically produced foods on human health; giving rise to the more appealing shift towards production systems that are deemed more soil, environmental/ ecologically friendly; such as conservation/ ecological/ organic production systems.

If all Nitrogen was up taken by the plants - maybe. But how would you ensure that?

First the soil test is very important. After that on the basis of soil test results you can choose appropriate fertilizers. Anything in a very high or in low amount is harmful to the soil and environment as well. So, use only recommended dose and choose your fertilizers on the basis of soil testing.

In soil and rizosphere zone there are pathogen which can reduce their activity from N efficiency but will recover after reduction N eficiency.

I don't think so, Sir. Without testing the field soil we can't recommend the proper dose of nitrogen. Then we have to think to apply nitrogenous fertilizers judicially, not to apply efficiently concerning safety growth and development of crops and environment.

Another important point is that the essential element nitrogen is not the only one factor for growth and development of plants. Without proper application of other essential elements like P, K, S, B, Zn etc. how can we think of better crop yield ensuring both food and environment security?

If N use efficiency is increased,it reduced soil and water pollution

Integrated nutrient management which involves physical, chemical and biological measures will definitely ensure food and environmental security.

I will answer this question again, what depends on what plant is grown and on what soils under what climatic conditions ?! Initially, you need to test the soil. Analyzing having learned the content of AF and K at least in it. What is the purpose of choosing the optimal rate and ratio of fertilizer for each crop, including nitrogen. Otherwise, not only does the yield not increase, but the soil becomes infected.

Nitrogen is the universally deficient macro soil nutrient, that's basic. If NUE is increased over Time-dimension( Ex- slow release 'N' fertilizer) then it is well n good. So my view point is Its not the debate about good or bad but it is debate over "HOW we are going to increase NUE, the method"?

Yes. I think it the way is to increase the N use efficiency!

By increasing N use efficiency loss of N can be reduced ultimately decreases water pollution leading to environmental security besides creating food security

In my opinion, although high nitrogen consumption is not guaranteed to increase yield due to the very complex relationships between nutrients in the soil and plants, it can also endanger the health of the environment by washing and entering groundwater.

NUE is an important concern in plant nutrient management, but by increasing it direct contribution cannot be made in increasing food and environmental security.

The most efficient way is to conduct soil testing for fertilizer recommendation to conserve the soil and to balanced soil fertility.

More NUE means less nitrogen loss attributing towards environmental pollution

The dosage is important, and it depends on the crop, soil, humidity, application form and phenological phase and application.

Let me add a new element in the discussion. Plants take up about 50% of their nitrogen needs from indigenous soil N even when apply optimum fertilizer N dose. But that does not mean that rest of the 50 % of applied fertilizer N is going to be lost to the environment. The fact is that a large portion of the remaining fertilizer N is going to become a part of the big soil N pool. And this will become available for plant uptake or loss from the soil-plant system in several subsequent years exactly the way now the plant has taken up about 50 % N from the soil N. We need to understand role of fertilizer N use efficiency keeping these processes in mind.

Interesting Dr. Bijay Singh ji. Nitrogen is the only element which is being discussed for long and it will be discussed in the same context in future also. The dynamics it follows is unique. Though there are 15N studies yet, it reflects that inspite of adequate N to soil is applied, 50%around comes from the soil pool. More the capacity of the soils to convert the applied fertilizer N into the body tissues of microbes and subsequent releases to the medium when solution N reduces and less chances to convert to very slow N, fertilizer use efficiency will be more and environmental losses will be less.

May I ask all those who are following this question to go through the attached publication.

Nitrogen applied to plants means healthy plants with high yield beside it is important for environment security

High NUE means lower amount of N to be applied, so coverage of N will be more for other crops, means higher production and also good for environment.

I have a query to Bijay Singh and Bikas S Mahapatra Sirs:

1. Application of split doses is beneficial for N management. Why Agronomists are not developing user friendly tools for application of N in splits.

2. Yes sir I am focusing on soft tool / simple mobile Aap for precision N management.

3. Leaf colour chart is there for some crops. This is comprised of color gradients (R-G-B). Can it be converted into mobile App? Presently, in developing countries also farmers (or their family members) are using smart phone.

5. Farmers need user friendly tools. Neither Green Seeker nor chlorophyll meter. Smartphone may be considered as an easy tool.

6. I think, yes it can be. Algorithms can be developed by using AI and ML to determine need of N application.

Regards to revered Professors. 8910889401

Thanks Dr. Maitra.

Science, professionalism and implementation of Science under practical field conditions are different in our subcontinent than the order in which agriculture is dealt in developed economy.

Attitudes need to be changed for making agriculture management more professional than only prescription.

Precision agriculture is the need of the country. However, differences exists between policy makers and scientific innovators.

Sustainability of agriculture, ecology, environment and economics all are waiting for the Precision agriculture to come forward.

Dr. Bikas is right in advocating attitudinal changes. This would bring in trememdous change for the better. Each situation is independent of the other and deserves treatment accordingly. Once you follow this basics, you reach rich harvests.

Sagar Maitra A lot is being done to develop farmer-friendly tools which can help him use fertilizer N at appropriate times and appropriately does. You may like to go through the attached review of mine to start with.

Not et al

Application of only nitrogen neither can increse crop yield nor insure food secreuity

Thanks a lot Prof Bikas S Mahapatra and Prof Bijay Singh sirs for your valuable comments. Regards.

Maybe this paper can help you. It's about NUE

Article Chloride Improves Nitrate Utilization and NUE in Plants