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Fertilizer & Agriculture

BIOFERTILIZERS :

OPPORTUNITIES AND CHALLENGESRenuka Kholkute

India

Introduction

In last century chemical fertilizers became popular throughout the World. They were associated with instan-taneous increased in the crop yield, thereby increasing the profit to the farmers. But in recent years notable environmental damage is ob-served because of their continuous field applica-tion and overuse. Water and soil pollution, loss of micro-organisms and beneficial insects and overall reduction in soil fertility are some of the ill effects of chemical fertilizers. Sole dependence on chemical fertilizers for future agricultural growth would mean further loss in soil quality and increased environmen-tal pollution. Modern day farmers are now showing interest in more eco-friendly products. Biofertilizers hold promising future in reducing soil quality prob-lems with optimum crop yield.

What are Biofertilizers?

Biofertilizers are complex product of live microbial inoculants which are able to fix atmospheric nitro-gen, solubilize soil phosphorus, decompose organic material or oxidize sulphur in the soil. Biofertilizers

are artificially multiplied cultures of beneficial soil microorganisms that can improve soil fertility and crop productivity. They add nutrients through the natural processes of nitrogen fixation, solubilizing phosphorus, and stimulating plant growth through the synthesis of growth-promoting substances. They are made from biological wastes and do not contain any chemicals. The main sources of biofertilizers are bacteria, fungi and cynobacteria (blue-green algae).

Why Biofertilizers?

Biofertilizers offer a new eco-friendly technology which would overcome shortcomings of the con-ventional chemical based farming. Biofertilizers showed positive influence on both soil sustainability and plant growth. They gradually improve soil fer-tility by fixing atmospheric nitrogen. They increase the phosphorous content of the soil by solubilizing and releasing unavailable phosphorous. They help in restoring depleted nutrients of the soil. Growth pro-moting substances released by biofertilizers improve plant root proliferation. They also guard the plant against some soil-borne diseases.

In addition to these advantages, biofertilizers are commercially promising too. They are comparative-ly cheaper than the chemical fertilizers. When used as a supplement to the chemical fertilizers, biofertil-izers can decrease the dose of chemical fertilizers. It

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cotton (Gossypium spp.), pulses, oilseed crops like caster, rice (Oryza sativa) and vegetables.

• Blue Green Algae (BGA) are photosynthetic nitrogen fixers and are free living. BGA fix at-mospheric nitrogen and are used as inoculations for rice (Oryza sativa) crop. BGA play a role in the nitrogen economy of tropical rice soils. They too add growth-promoting substances in-cluding vitamin B12, improve the soil’s aeration and water holding capacity and add to bio mass when decomposed after life cycle.

• Azolla is an aquatic fern found in shallow water bodies and in rice fields. It has symbiotic rela-tion with Blue Green Algae. Large biomass pro-duction is characteristic of Azolla. The biomass is used as a green manure in rice (Oryza sativa) cultivation. So, Azolla can help rice or other such crops through green manuring.

Biofertilizer Market

Biofertilizers were commercially introduced in 1895 by Nobbe and Hiltner. They produced a laboratory culture of Rhizobia called Nitragin. In India, the commercial production of biofertilizer commenced in 1956. But the growth in biofertilizer sale was very slow till 1980s. Major factors behind this were lack of awareness about biofertilizers amongst the farm-ers and its slow influence on crop yield.

Biofertilizer production and consumption started rising considerably since last 5 years. Presently, in India, most commonly produced and marketed bio-fertilizers are Rhizobium, Azotobacter, Azospiril-lum and Phosphate Solubilising Bacteria (PSB). In 2011-12, the annual production of biofertilizer is re-corded at about 40,324 tonnes in India (Table No. 1).

results in reduced cost of fertilization. They help in increasing the crop yield by 10-25%.

Impact of Biofertilizers on Crops

Biofertilizers can be put broadly into two groups viz., inoculants of specific organisms like Rhizobia, Azotobacter, Blue Green Algae, Phosphate Solubi-lizer, cellulolytic microorganisms, etc. and biomass producing organisms e.g. Azolla. Some of the popu-lar biofertilizers and their impact on various crops are discuss in short here.

• Rhizobium inoculants are used for leguminous crops. These inoculants have ability to fix atmo-spheric nitrogen in symbiotic association with root-nodule forming plants. Along with this, in-oculated legumes found to leave behind some residual nitrogen in soil after harvesting. It is adventitious to the subsequent crop. Response to Rhizobium inoculation has been found ben-eficial for principal legumes such as Pigeon Pea (Cajanus cajan); Chickpea (Cicer arietinum), Green gram (Vigna radiata), Soyaben (Glycine max) and broad bean (Vicia faba).

• Azotobacter inoculants can be applied to many non-leguminous crops. It is free living and non-symbiotic nitrogen fixing organism that also produces antibodies that suppress many root pathogens. They promotes seed germination and initial vigor of plants due to growth sub-stance (IAA) produced by the micro-organisms. Azotobacter can be used for crops like cereals, millets, vegetables, cotton (Gossypium spp.) and sugarcane (Saccharum spp.).

•Azospirillum is also a nitrogen-fixing micro or-ganism used for non-leguminous plants. Besides ability to fix nitrogen, Azospi-rillum is known to secrete sub-stances promoting plant growth. Azospirillum inoculations have been found beneficial mainly for millets, maize (Zea mays), sorghum, wheat (Triticum spp.) and sugarcane (Saccharum spp.).

• Phosphorus Solubilizing bacte-ria and fungi converts chemi-cally fixed soil phosphorus into available form. Phosphate Solubilizing Bacteria (PSB) are a group of beneficial bacteria capable of hydrolysing organic and inorganic phosphorus from insoluble compounds. PSBs are found useful for variety of crops such as wheat (Triticum spp.), sugarcane (Saccharum spp.),

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The present level of biofertilizer use is still quite low and there is a considerable potential to increase in its sale in coming years. According to the latest report of markets and markets (a leading market research company and consulting firm), “the global market for biofertilizers in terms of revenue was estimated to be worth around $5,013.1 million in 2011 and is expected to reach $10,298.5 million in 2017 grow-

ing at the CAGR of 12.8% from 2012 to 2017. Europe and rest of the World countries especially Latin America are the two top consumers of biofertilizers in the world. Growth is particularly high in emerging countries such as China, India because of rising awareness among the farmers about the hazards of chemical fertilizers as well as the higher costs of chemical fertilizers”(4).

Future Prospects for Biofer-tilizer Industry in India

Integrated Nutrient Management (INM) has gained importance in recent years from the sustain-ability point of view. INM tech-nology covers combine use of organic manures, green manures and biofertilizers with minimum use of chemical fertilizers to produce optimum crop yields. Consequently, biofertilizers de-mand can be expected to rise in near future.

Another important aspect for the bright future of biofertilizers

is increasing popularity of organic food among the buyers. Organic foods are produced using methods of organic farming. Organic farm-ing does not involve use of synthet-ic pesticides and chemical fertilizers. Biofertilizers are imperative element in organic farming. Increased aware-ness towards chemical free organic and natural food sector is expected to grow considerably in near fu-ture. According to The International Federation of Organic Agriculture Movements (IFOAM), India ranks first, recording 5,47,591 organic producers in 2011(3). Today, organic products are becoming popular in major Indian metro cities like Delhi, Mumbai, Kolkata, Pune, Ahmad-abad, Chennai, Bangalore, etc.

Maharashtra State tops in biofertilizers, producing 8743.69 tonnes followed by Uttar Pradesh (8695.08 tonnes). Agro Industries Corporation, State Agricul-ture Departments, National Biofertilizers Develop-ment Centers, State Agricultural universities and private biofertilizer companies are the vital players in biofertilizer market.

Fertilizer & Agriculture

in desired numbers. Mother culture stage, carrier selection, broth culture stage, mix-ing of broth with carrier, packing and stor-age stages during biofertilizer production needs quality control. The Bureau of Indi-an Standards (BIS) has evolved methods to check the quality of inoculants and is-sue ISI certificates to qualified producers. BIS has prepared quality control specifi-cation for following inoculants :

• Rhizobium Inoculants - IS:8268:2001

• Azotobacter Inoculants - IS:9138:2002

• Azospirillum Inoculants - IS:14806:2000

• Phosphate-Solubiliser - IS:14807:2000

Conclusion

Biofertilizers increase the availability of plant nutri-ents and can help in maintenance of the soil fertil-ity over a long period. As discussed earlier, some of the microorganisms have the beneficial role of bio-logical nitrogen fixation to supply nitrogen to crops, solubilizing insoluble phosphates to plant available (soluble) forms and synthesizing biomass for manur-ing crops like rice. Biofertilizers are therefore eco-nomical, renewable and eco-friendly, but they can-not replace chemical fertilizers totally.

Biofertilizer is an important component of Integrated Nutrient Management and organic farming. These technologies are becoming vital in modern day agri-cultural practices. The changing scenario of agricul-tural practices and environmental hazards associated with chemical fertilizers demand more significant role of biofertilizers in coming years.

References1) http://ncof.dacnet.nic.in/OrganicInputproductionsta-

tistics/BFandOFProductionstatistics2010-11to2011-12.pdf

2) http://ncof.dacnet.nic.in/3) http://www.organic-world.net/2419.html?&L=04) Global Biofertilizers Market by Types (Nitrogen fix-

ing, Phosphate Solubilizing, and Potash Mobilizing), Applications & Geography - Trends & Forecasts to 2017. http://www.marketsandmarkets.com/Market-Re-ports/compound-biofertilizers-customized-fertilizers-market-856.html

5) Nilabja Ghosh. Promoting Bio-fertilizers in Indi-an Agriculture. http://www.ipni.net/ipniweb/portal.nsf/0/94cfd5a0ed0843028525781c0065437e/$FILE/12%20South%20Asia.Ghosh.Promoting%20Bio-fertilizers%20in%20India%20Agri.pdf

6) Pindi PK (2012) and SDV Satyanarayana. Liquid Micro-bial Consortium- A Potential Tool for Sustainable Soil Health. J Biofertil Biopestici 3:124. doi:10.4172/2155-6202.1000124. http://www.omicsonline.org/2155-6202/2155-6202-3-124.pdf

Source : FiBL-IFOAM survey 2013, based

on National data sources(3)

Limitations of Biofertilizers

Apart from the slow effect of biofertilizers on crop growth, other limitations are shorter self life, sen-sitivity to temperature, handling difficulties during storage and transportation. The main challenge of the biofertilizer production units is the viability of organisms up to field application. Some of the ben-eficial organisms are very effective in vitro, but may fail at some stage of cropping, even at the stage of harvesting (6).

Government Aid to Biofertilizer Industry

The Government of India and the various State Gov-ernments have been promoting the emerging biofer-tilizer market both at the level of the user-farmer and the producer-investor through farm level extension and promotion programmes, financial assistance to investors in setting up units, subsidies on sales and direct production of biofertilizers in public sector, cooperative organizations, universities and research institutions(5).

Ministry of Agriculture, Government of India imple-mented a central sector scheme “National Project on Development and use of Biofertilizers (NPDB)” dur-ing the 9th Five Year Plan. As a part of this project, a subsidy up to Rs. 20 lakhs was provided for setting up a biofertilizer production unit of 150 TPA (tonnes per annum) capacity.

Later on this scheme was merged in “The National Project on Organic Farming (NPOF)” launched dur-ing 10th Five Year Plan. Planning Commission ap-proved the scheme as pilot project with an outlay of Rs. 57.04 crore. The scheme continues in the 11th plan with an outlay of Rs. 101.00 crore(2).

Apart from the financial support, Government is also involved in quality maintenance. Quality of biofer-tilizer inoculants is one of the most essential factors in marketing of biofertilizers. It assures the presence of right type of microorganism in active form and

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