Production and use of organic fertilizers: A variety of different organic fertilizers can be used to supply plant nutrients and improve the condition of the soil. Furthermore micronutrient and trace element imbalances can occur where farmers rely solely on inorganic fertilizers to supply the macro nutrients and one or two secondary nutrients. Organic fertilizer can be produced from the recycling of farm wastes such as crop residues, animal manure and kitchen waste. A range of green manures can be grown on farm to supply plant nutrients and organic matter for incorporation into the soil (e.g. herbaceous legumes grown in a crop rotation, or agroforestry systems where the leaves and stems of nitrogen fixing trees/shrubs are used to fertilize adjacent crops). Some farmers may have access to off-farm sources of organic fertilizer (chicken/pig manure from commercial producers, silt from fish/prawn ponds, sugar factory waste, urban refuse etc). The FFS participants could investigate the costs and benefits of alternative organic fertilizers e.g. making compost, using green manures, improved storage of farm yard manure, incorporation of crop residues. • Inorganic fertilizer: There is frequently a variety of different types of inorganic fertilizer available to farmers and they may have a limited understanding of which are the best for their specific circumstances. There is therefore scope for the FFS participants to learn about the differences between compound and single nutrient fertilizers and how to compare fertilizer costs in relation to the amount of nutrients supplied, for instance a bag of Urea typically costs more than a bag of Sulphate of Ammonia but is usually cheaper per unit of nitrogen supplied. The participants can also test (perhaps as part of module IV) different amounts of, and ways to apply, inorganic fertilizer, plus comparing the costs and benefits of inorganic versus organic fertilizers and combinations of the two.

@ Dr. Singh, I personally feel the important factors are soil texture, mulch on the soil surface, level of soil disturbance, crop rotation and soil organic matter status.

Sir,

Got an article related to the topic and it may be helpful.

Attaching the same and giving the link ( http://www.fftc.agnet.org/htmlarea_file/library/20110722063019/eb341.pdf )

Sagar Maitra

1. Minimal disturbance to the soil for crop cultivation

2. Retaining and managing crop residues in the current crop for soil temperature moderation, soil moisture conservation and nutrient addition through decomposition

3. Crop diversification for restoring soil fertility which is done through inclusion of a legume crop or short duration pulse crop in the exsisting cropping system.

The most important factor is organic matter

Carbon fractions most important and the nutrients enhancement. Both are important. Sagar Mitra sir conservation is not only related to N, its related to all nutrients and the soil physical conditions, biological conditions...

The major factors include:

1. Soil moisture

2. Soil aeration

3. Soil biological activity

4. Degree of soil compaction

5. Nutrient requirement of succeeding crop

6. Rooting depth and mining volume for nutrients of the succeeding crop

7. Rate of decomposition of the crop residues

When applying Fertilizer it has to be ensure that there is sufficient Moisture present in soil hence Soil Moisture is a very important factor.

Otherwise,Inherent capacity of the soil should be known before applying Fertilizer,for that soil Fertility test can be done...then accordingly apply the required amount only as In case of Conservation Agriculture,Biological stimulation is much necessary which may get reduced by excessive Fertilizer application.

Under conservation agriculture, we are going to use cover crop for protecting the soil surface...excess of nitrogen has to be applied while doing conservation agriculture as we use straw or cereals by products , which need for amount of nitrogen for their decomposition...