Blue Green Algae Bio Fertilizer Technology

Navratna Journal

JAN-FEB 2008

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Blue Green Algae Biofertilizer Technology for rice based cropping system of Western Orissa

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o o o Orissa state(81 27’ E, 17 49’ N to 87 39’ o E,29 34’ N)is one among the few principal rice growing states of India. Based on soil type, climatic water balance, intensity and duration of rain fall and topography Orissa is divided into 9 agro climatic zones. Out of these 9th agro climatic zone, Western and mid central table land comprises major rice growing areas of Orissa. Bargarh and adjoining regions harvest rice crop twice a year and serve as a rice bowl for Orissa and its neighboring state. As, rice is a staple food for all most all people of this region, study on the modern rice cultivation practice and specifically soil nutrient study have made tremendous interest for agricultural scientists, officials, workers and farmers of this region. Nitrogen is one of the most essential fertilizers for crop plants. Though it constitutes over 70% of our atmosphere, the crop plants are unable to exploit it directly from the nature. To support crop production the fertilizer consumption has increased to many folds. Several thousands tones of chemical fertilizers consumed per year(two cropping seasons) alone in Bargarh and adjoining regions of Western Orissa .Increasing cost of chemical fertilizers, reduction/abolition of subsidy, widening gap between supply and demand together with low level of purchasing power of majority farmers of this region have indeed created an embarrassing problem. Also the chemical based system of rising crop has degraded the soil environment (altered C/N ratio) which has cumulated in reduced agrochemical utilizing efficiency of crop plants. Chemical characteristics of soil samples of many places of Western Orissa also

Some blue-green algae produce toxins that could pose a health risk to people and animals when they are exposed to them in large enough quantities. Health effects could occur when surface scums or water containing high levels of blue-green algal toxins are swallowed, through contact with the skin or when airborne droplets con-taining toxins are inhaled while swimming, bathing or showering.

Dr.Jayanta Kumar Sahu shows this trend(Sahu,Naik and Adhikary,1996).It is therefore time to think for some of the alternative natural resources to meet part of our demand and to relieve the pressure on the chemical fertilizer nitrogen required. Under water logged conditions of rice fields, Blue Green algae plays a vital role in maintaining soil fertility and crop yield even in the absence of any added agrochemicals. In recent years, algalisation has been recognized as an important input in rice cultivation as its form a perpetually renewable source of nutrients and improve soil health (Venkatraman, 1981; Goyal,1993) Cyanobacterial biofertilizer for rice cultivation is an eco friendly, easily manageable input forming a self generating system contributing to about 25 Kg N/ha per season and also they add organic matter and growth promoting substances to the soil (Roger and Kulasooriya,1980). A survey on the distributional pattern of Blue Green algae on all nine agro climatic zones of Orissa was studied. Rich diversity of Blue Green algae comprising specie of Nostoc, Anabaena ,Aulosira,Calothrix,Tolypothrix and Cylindro spermum was observed in the several rice fields of Western Orissa (Naik, Sahu and Adhikary, 1996) .Out of the eight different strains of Nitrogen fixing Blue Blue-green algae (BGA) are primitive microscopic plants that live in fresh water. Their scientific name is cyanobacteria but they are more commonly known as pond scum. Normally blue-green algae are barely visible, but, during warm weather, populations can rapidly increase to form a large mass called a bloom. Blooms most commonly occur during the late summer and early fall.Blue-green algae thrive in areas where the water is shallow, slow moving, and warm, but they may also be present below the surface in deeper, cooler water. One key factor affecting growth rates is the level of available nutrients such as phosphorus and nitrogen

Navratna Journal

JAN-FEB 2008

Green algae suggested for biofertilizer production in Orissa, one efficient Nitrogen fixer Nostoc carneum UU 29130 belong to Western part of Orissa, Padampur. Also this strain has been deposited in BGA germplasm conservation centre at Indian Agricultural Research Institute, New Delhi .This strain is a region specific stress compatible strain, therefore, this species can be recommended for biofertilizer production by farmers in this region.A tested (rural oriented) method is described below which is recommended for setting up large scale algal production farm in this region. Mass production in cemented tanks Out of the different method recommended for the production of BGA, open air cement tank method is considered to be easy and cost effective. The cement tanks are permanent structures and can be cleaned easily. On the other hand galvanized iron trays are very expensive, prone to rusting and difficult to clean. Similarly polythene lined pits don’t last for more than 3-4 harvests and thus become costly. Production of BGA inoculum can be done in the following steps • Construct cement tanks of size5m length,1.5m width and 0.3m depth in an open space. The inner walls and floor of the tank should be glazed smooth. Provide a water tap at about 25 cm height at one of the broad sides and a drainage pipe fitted on the opposite wall at the bottom. An overflow outlet is provided at about 20 cm height above the drainage outlet. The length of the tanks can be manipulated but width should not be increased. Provide a space of about 1.0 m between the tanks for operational convenience. • The four corners of the tank should be round. • Spread 10 kg of soil and add 200 g of single super phosphate per tank. The soil should be loam and sandy loam and heavy type like clay. Light soil facilitates formation of algal flakes which easily separate

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Avoiding exposure to blue-green algae Never drink untreated surface water, whether or not algae blooms are present. Untreated surface water may contain other bacteria, parasites or viruses, as well as algal toxins, that all could cause illness if consumed. People not on public water supplies should not drink surface water, even if it is treated, during an algal bloom because in-home treatments such as boiling and disinfecting water with chlorine or UV and water filtration units do not protect people from

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out from the soil. The soil should be preferably taken from a fallow land since it is low in Nitrogen and microbial flora. • Fill the tanks with water up to a height of about 15 cm and add insecticide(10-15ml malathion, 50% EC or endosulphan 30% EC) to prevent breeding of mosquitoes and other insects. Mix the contents thoroughly and allow to stand till the supernatant becomes clear. •Sprinkle 200 g of BGA culture on the water surface(mother starter region specific BGA cultures are available at Utkal university BGA germplasm conservation centre, Bhubaneswar) • Under favorable conditions (temperature 300 C and above), the growth of blue-green algae will be rapid and a thick algal mat is formed on the surface of the water in about 10-15 days. At this stage, formation of another BGA layer can be seen on the surface of the soil. During this period, add water periodically to maintain the water level around 10 cm. • Closely monitor the BGA coming up in the tanks by periodically examining the algal growth using a microscope. One can alternatively use the iodine test to differentiate between green and blue-green algae. The green algae turn dark violet or black in colour with iodine. • Alkaline conditions with pH around 8, appreciable prevent contamination with green algae. • Stop adding water to the tanks only after a thick BGA mat is formed and allow the contents to dry without draining the water. • When completely dry, the algal mat will form flakes which will separate out from rest of the soil. These flakes are collected, sun dried and packed in polythene bags. • Fill the tanks again with water, put fresh soil, starter culture and super phosphate and repeat the process. Single harvest from a tank yields about 710 kgs of soil based algal flakes. blue-green algal toxins. If washing dishes in untreated surface water is unavoidable, rinsing with bottled water may reduce possible residues. While we don’t know if water containing low levels of blue-green algal toxins could leave residues on dishes, taking this precaution may help reduce possible exposures. People, pets and livestock should avoid contact with water that is discolored or has scums on the surface. Colors can include shades of green, blue-green, yellow, brown or red. If contact does occur, wash with soap and water or rinse thoroughly with clean water to remove algae.

JAN-FEB 2008

microscopic structure of Blue Green Algae

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in order to gain a benefit of 15-25 kg N/ha. Where the nitrogenous fertilizers are used, keep the basal dose unchanged and reduce the subsequent two applications by half. This will save on the chemical fertilizers without affecting the yield. • Apply BGA at least for 3-4 consecutive seasons to have the advantage of cumulative effect. • The sun dried BGA inoculums packed in polythene bags can be stored at room temperature for at least 3 years without loss in the viability. • Recommended pest control measures and other crop management practices generally do not interfere with the establishment and activity of the BGA in the field. Cyanobacterial toxins are the naturally produced poisons stored in the cells of certain species of cyanobacteria. These toxins fall into various categories. Some are known to attack the liver (hepatotoxins) or the nervous system (neurotoxins); others simply irritate the skin. These toxins are usually released into water when the cells rupture or die. scientists are more concerned about hepatotoxins than neurotoxins, because neurotoxins are not considered to be as widespread as hepatotoxins in water supplies. Very few cyanobacterial toxins have actually been isolated and characterized to date. Better methods of detection are being developed to help us learn more about them,

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• Application of small quantity of phosphatic fertilizer after BGA inoculation accelerates the algal establishment. The above algal biofertilizer technology is rural oriented technology for farmers resulting in low cost production of rice. This is of particular significant to the farmers of this region who are economically weak to invest on chemical Nitrogen fertilizer. Fields experiment using algal inoculations at various location showed promising results with respect to nitrogen saving and increased yield. Large scale production of the soil based BGA biofertilizer has an income generating potential and can be taken as a profession for the unemployed youths of this region. REFERENCES Mass cultivatuins of Blue Green Algae

• Instead of using the soil based starter culture, one can use laboratory grown liquid culture of rice fields BGA to inoculate the tanks. Even the dominating native BGA, directly collected from rice field can also be used. Recommendation for Field Application • Broadcast the dried algal flakes on standing water at the rate of 10 to 20 kg per hectare ,one week after transplantation. The field should be kept water logged for about ten days after inoculation to allow good growth of BGA. • If nitrogen fertilizers are not being used, apply BGA

Free floting BGA in rice field of Western Orissa

Navratna Journal

Goyal,S.K.1993.Algal Biofertilizer for vital soil and free Nitrogen.Proc.Indian Natl.Sci.Acad.B.59:295-302. Naik,H.K.;Sahu,J.K.and Adhikary,S.P.1996.Blue Green algae of rice fields of Orissa state 11.Growth and Nitrogen fixing potential.Phykos, 35(1&2):111-118. Roger,P.A.and Kulasooriya.S.A.1980.Blue Green algae and rice,I.R.R.I..,Los Banos,Manila,Phillipines.pp.1-112. Sahu,J.K.;Naik,H.K.and Adhikary,S.P. Blue Green algae of rice fields of Orissa state 1.Distributional pattern in different agroclimatic zones. Phykos ,35(1&2):93-110. Venkataraman,G.S.1981.Blue Green algae for rice production,a manual for its promotion:FAO field documentation no.2(RAS/75/ 004),FAO, Rome.pp.102.

T.F.College , Bargarh Despite their name, blue-green algae are not algae at all. They are a type of photosynthetic bacteria, called ‘cyanobacteria’, that rely on sunlight for energy.Blue-green algae are present in almost all aquatic ecosystems, including creeks, rivers, lakes and wetlands. Individual cells are quite small, so bluegreen algae can be present in a water body without being visible. However, as environmental conditions become just right, algae numbers can start to increase rapidlyand blooms, or scums, become easily visible across the water surface. The blooms range in colour from dark green to yellowish–brown and develop a paintlike consistency as they dry out around the water’s edge. A blue pigment may also be seen as they dry.