Hi Mr. Khoshru,

In my expertice using biofertilizer these don´t have negative effects for themselves. Their efficiency depends on the humidity and texture of soils, and also for microclimate.

Each plant has different root system, and their own microbiota community for produce and put available nutrients for plants.

One of the serious problems of Biofertiliser in India is that there are no standards or specifications for it. So there is no way to know what it is and its efficacy, by mere visual and touch checks.

Researchers around the world are divided in two frames of mind. One group doesn't advocate to use microbes from non-native sources ,otherwise it will disturb the native microbial fabrics of the rhizosphere; while other group of research

ers are very strong proponent of using only the native isolates ,in addition to what other two colleagues expressed.

no longer exposed to damage to the soil, human, animal and the environment in general as a result of the use of more chemical fertilizers in addition to their impact on water and air through the volatilization of one reason or another. Therefore, it was necessary to find alternative means to ensure the safety of human health and microorganisms and animals and achieve economic profitability as a result of improved quantity and quality of the material produced, the tendency to use bio-fertilizers that reduce the cost of being farm products, and limit the use of chemical fertilizers, / 17 / years and 17% of the quantities used and cause diseases to humans and animals.

So what are bio-fertilizers?

Biofertilizers are preparations that contain microorganisms capable of supplying plants with the necessary nutrients from natural sources and have the ability to release nutrients on an ongoing basis, thus making them sufficient to cover the needs of the treated plants, by dismantling the materials in the soil, especially the nitrogen and preparing it for the plant, On the use of chemical fertilizers, by the installation of atmospheric nitrogen or by dissolving organic phosphate and converting it from an unsuitable image into a soft absorbable form by plants, Li competition for the duration of their stay in the soil and on the predators resistance Almtteflat in the soil, are not affected by the chemicals added to the seeds in order to protect them, and have a high capacity to achieve the objective of the use, particularly resistant to drought and heat, whether these organisms whether the form of liquid or a solid image

Why should we blame so much to chemical fertilizers alone , there are other plant protection chemicals used so heavily in modern day agriculture , they are never blamed to face the brunt of such discussion . For example, use of herbicides , just imagine the magnitude of damage brought about by herbicides with regard to rhizosphere ecology , regardless of soils and crops...

Despite all these claims , biofertilizers have not been able to create the desired niche in modern day agriculture, despite teh fact that they are simply indispensable to agriculture to survive through any kind of sustainability. Lets debate on those issues, what shall we do to make biofertilizers more responsive to modern day agriculture.....

I just finished a 6 month study using Bacillus Subtilis that was fermented on a soybean meal substrate. It functioned very well as a rhizo bacteria growth promoter. Absolutely no negative effects. Two acute drought tolerances of the treated tomato plants were dramatic compared to the non treated plant

I support the use of biofertilizers. Some of you have expressed the positive reasons for your current use. Economically they turn out to be an important alternative to consider in the management of the crops in areas of small and medium producers, as well as in zones of low availability of inorganic fertilizers. Speaking from the ecological point of view, I am of the idea of ​​using only biofertilizers based on microorganisms isolated from the same area, farm or even paddock. Even in this way the agroecosystem is being affected. In the sense that it is favoring the most adapted microorganisms in that sector, to express them in a way. In our country (Venezuela) biofertilizers have been in some agricultural areas for some years. I have not known of negative effects in the use of biofertilizers. However, it is necessary to evaluate how is the behavior of this agroecosystem currently after the continuous use of biofertilizers. Keep track and control This will allow to take forecasts in case of negative effects.

Some researchers have used inorganic fertilizers (N-P-K) in conjunction with biofertilizers (nitrogen-fixing bacteria and phosphorus-binding bacteria). Since biofertilizers can hardly supply the total of the needs of these nutrients in varieties or hybrids today. This task is important to continue and thus can be saved in two ways, in the production of inorganic fertilizers (which is expensive) and saves the producer by paying less for biofertilizers (compared with the costs of inorganic).

Gram positive spore forming bacteria such as bacillus Subtilis act as excellent rhizobacteria growth promoters as well being endophytes that can cause induction of the host immune system. In my work I have seen nothing but dramatic positive results and no apparent negatives. Bacillus biomass can be produced quite easily and at low cost on waste substrates. The substrate I use is soybean meal.

Although cases in which biofertilizers have negative effects on crops are scarce, they can occur. Fernández et al. (1992), showed the low response found in the development of coffee postures with the use of three strains of AMF and a strain of Pseudomona fluorecens, finding in most cases an effect significantly negative in the fungal parameters and in the development of the mycorrhizal symbiosis in general. Edaphic and biological factors in humid tropical regions or in good soil irrigation, such as the specificity of the type of Phosphorus Solubilizing Rhizobacteria (PSR) strain to be used with the soil in issue can undermine the favorable effect exerted by these types of bacteria on mycorrhizal associations goes (Mamoun and Olivier, 1989).

Fernández, F./et al/. 1992 Efectividad de tres hongos formadores de micorrizas VA y una cepa de bacteria solubilizadora de fósforo sobre el crecimiento de posturas de café (Coffea arabica. L.). Cultivos Tropicales. 13 (1). 28-32. 1992.

Mamoun, M.J., Olivier, J.M. 1989. Dynamique des populations fongiques et

bacterinnes de la rhizosphere des noisetiers truffiers II. Chelation de fer et

repartition taxonomique chez les Pseudomonas fluorescents. Agronomie. 9: 345-

351. 1989.

Dear Dr. Bahman Khoshru

In the article: Soil–strain compatibility: the key to effective use of arbuscular mycorrhizal inoculants? Ricardo A. Herrera-Peraza, Chantal Hamel, Félix Fernández, Roberto L. Ferrer & Eduardo Furrazola. 2010. Mycorrhiza DOI 10.1007/s00572-010-0322-6 you can see also some ideas about that, best regards, Eduardo.

Inconsistant performance by the inoculants or inconsistant response from the plants due to various external and internal factors are the disadvantage of biofertilizers. It seems that there is very limited or no negative effects due to the application of biofertilizer.

When the evaluated response is performance and / or production, it seems that the effects are more positive than negative. However, we must continue evaluating the effects of biofertilizers on the scale of populations of native microorganisms (as mentioned), that is, at the level of the agroecosystem.

Dear colleagues all

A good debate has been organized around this question. We are fervent defenders of the biofertilization, in fact our country undertook at the beginning of the 90s of last century one of the greatest efforts at the level of the Third World for the use of arbuscular mycorrhizas in agricultural and forestry plans throughout the country. As example: Ricardo A. Herrera-Peraza, Chantal Hamel, Felix Fernandez, Roberto L. Ferrer and Eduardo Furrazola. 2011. Soil-strain compatibility: the key to effective use of mycorrhizal arbuscular inoculants? Mycorrhiza (2011) 21: 183-193. DOI 10.1007 / s00572-010-0322-6. However, without doubt, there may be a lack of response to mycorrhizal biofertilization in some cases.

Let us return then the dynamics of mycorrhiza formation of Bethlenfalvay et al. (1982). According to these studies, the biomass of external mycelium at the fourth week of growth of a mycorrhized plant represents approximately 20% of the value that will reach for the tenth week. While, the biomass of endophyte during this lag period represents only 1% approximately of the biomass that inhabits the interior of the rootlets during the stabilization phase (week thirteenth onwards).

After the lag period, and as the plant increases its production of photosynthates and satisfy the demands of the AM fungus, the ratio between the biomasses of external and internal mycelium drops sharply until approaching the unity (1). During this period, it coincides with the log phase (logarithmic or exponential) of the mycorrhizal colonization, the arbuscular endophyte biomass increases as the external mycelium increases more or less proportionally. The future success in the positive effect of the mycorrhization process on the growth of the host plant depends, in the last instance, on the balance between the biomasses of external and internal mycelium present in the rootlets, consistent with the possibility of adapting their photosynthetic efficiency to the requirements of the fungus. Otherwise, if unfavorable environmental conditions occur, such as excess or nutrimental imbalances in the substrate as postulated by Bowen in 1985, lack of light, unfavorable pH values ​​of the soil, etc., mycorrhizae will consume photosynthates unilaterally unbalanced and lead to a parasitism process. That as Crush postulated since 1975 could be nothing benign and then cause a lack of response of the vegetable. Everything is based on a model developed many years ago, but which explained at the time this type of depressions of mycorrhizal growth observed in the literature.

No hemos encontrado efectos negativos con los biofertilizantes, por el contrario el efecto ha sido positivo

Applying of biofertilizers improve yield quantity and quality characters although there are little disadvantages concerning with using of biofertilizers e.g. soil must contain sufficient nutrients for biofertilizer organisms to grow well and work, biofertilizers cannot completely replace chemical fertilizers, biofertilizers lose their efficiency if soil is excessively hot or dry and biofertilizers must be used before their expiration date.

There are no standards, and so their efficacy is difficult to promise.

Extensive and long-term application of bio-fertilizers may result in accumulation of salts, nutrients, and heavy metals that could cause adverse effects on plant growth, development of organisms of the soil, water quality, and human health.

http://www.lrrd.org/lrrd24/3/carv24043.htm

Application of inoculants may have adverse effect on soil microbial community compositions. In my work (microbial ecology of aquatic environmet), for example, this may effect on nitrification and denitrification bacteria. so NH4 accumulate in water. I highly recommend use High throughput sequencing after utilization of biofertilizer on pilot scale.

do not use biofertilizers such recent decades....

Bahman Khoshru @@