Dear Ali Alhayany

Bio fertilizers are important components of integrated nutrients management. These potential biological fertilizers would play key role in productivity and sustainability of soil and also protect the environment as eco-friendly and cost effective inputs for the farmers. They are cost effective, eco-friendly and renewable source of plant nutrients to supplement chemical fertilizers in sustainable agricultural system.

There are several things need to be considered in biofertilizer making such as microbes’ growth profile, types and optimum condition of organism, and formulation of inoculum. The formulation of inocula, method of application and storage of the product are all critical to the success of a biological product. In general, there are 6 major steps in making biofertilizer.Includes choosing active organisms, isolation and selection of target microbes, selection of method and carrier material, selection of propagation method, prototype testing and large scale testing.

Soil organisms, play an important role in maintaining fertility. The utilization of Bio fertilizers there is no effect on soil organism. There are four levels of organisms: microflora, microfauna, mesofauna and macrofauna. Almost all soil organisms (except some bacteria) need the same things we need to live – food, water and oxygen. They eat a carbon-based food source which provides all their nutrients, including nitrogen and phosphorus. They require a moist habitat, with access to oxygen in the air spaces in soil. These reasons explain why 75% of the soil organisms are found in the top 5cm of soil. There are other factors that determine whether species can survive and grow, including pH, temperature, salt content, type of carbon and heavy metals.

Use organic fertilisers (eg manures) Organic fertilisers provide microorganisms with a stable food source which then provides long term slow release nutrients to the plants. Organic fertilisers have less adverse impact on soil populations but they should not be considered a substitute for mulching or ground cover.

Soil Organism depends upon following factors-

1. Maintain ground cover

2. Minimise physical disturbance

3. Build soil organic matter with green manure crops, mulch or pasture

4. Maintain adequate moisture

5. Rotate crops or have mixed species planting

6. Reduce the use of chemicals

7. Use Bio fertilizers.

8. Use organic fertilisers (eg manures)

9. Check the pH and modify it if necessary

10. Improve poor drainage by building good soil structure

11. Consider your soil as part of a complete agro-ecological system.

Regards,

Prem Baboo

Question and answers are diffuse until one defines what exactly a "bio-fertilizer" is. Till now its a bunch of stories and fairy tales with not much soild science behind!

That depends of the SOC content. High amounts of SOC maintain the control of the soil equilibrium, and then the impacts of the bio-fertilizers are only temporal.

Dear Ewald

I mean by the word Bio-fertilizers any type of organisms that used as nutrien product to the plant ,and by the increasing use of these microbes for decades is that thing would affect soil organisms population in types and numbers ,in another word would that lead us to another soil population in the futere?

Regards

Ali  Alhayany

Not Ali, no at all. If you have a hugue populations of millions of microbes by grams, one 'foreing' species has limited probability of surviving....; its permanency is only temporally if you do not protect it. You only have success if you have a low microbial population, i. e., if you SOM content is rather low. Is it not Ewald SNUCH...?  

Adding bio-fertilizers would certainly disturb normal distribution of soil organisms if adding fertilizers for these many years has disturbed the normal distribution of nutrients in soils, already!!

I suggest that you conduct a study on different rates of bio-fertilisers on different types of soils and measure the distribution of the soil organisms for empirical data to help answer the question.

We have worked with different biofertilizers such as Nitrogen fixers like Azotobacter, Azospirillum, Rhizobium; P mobilizers like Pseudomonas sp., Bacillus sp., as well as phosphatase and phytase producing organisms and FYM, Vermicompost,etc in Aridisol under Arid Environments where microbial population is very low and dominant microorganisms are mainly thermophilic with low microbial biomass and less organic matter content. We found that with the application of biofertilizers either seed inoculation or soil application is helping to increase total microbial population including dehydrogenase and esterase activities as well as microbial biomass along with minor improvement in organic matter content. But does not affect much on diversity of microbial population. They also help in reducing the soil borne diseases to the plants. So, I dont think of much changes in normal distribution of organisms due to the application of biofertilizers continuously rather it will help to increase in the population of beneficial organisms and decrease in pathogenic organisms population temporarily.

Exactly as Juan said!

Dr.Juan an Dr.Tarafdar,good comments.I agree with them.

If a bioculture /biofertilizer is brought from elsewhere(even other country) and continuosly used in new site for number of years ,what will happen to the genome of the foreign culture/biofertilizer and the native bacteria?Can any microbiologist /even others comment on this?

Dr. Rao, If they are strong enough to fight to the native population then they gradually build up but to my knowledge and experience there is every possibility to changes some of the uni-genes with time as compared to the original culture and they may be good or bad transformation.