Tips on improving soil fertilty - through cultivation of azolla

What is Azolla?

Red Azolla is a small, native, floating fern – one of only six, free-floating, aquatic fern species. It grows from 1 cm to 2.5 cm wide and is a bright green colour. Its colour changes to deep red when it is exposed to the sun, thus the name Red Azolla.
Azolla grows in waterways in dense patches, which can look like a green or red carpet. From a distance it may be confused with Salvinia, a noxious aquatic weed, or the scum of a bluegreen algal bloom.

Azolla culture -
Azolla which is one of the waterborne blue green algae or fern is mainly used as an organic fertilizer in rice field in many part of world. Azolla has micro leaves, fibrous roots as body parts & these small leaves are greenish from above & whitish in color below. However the anatomy of leaves has concern, these leaves have small vacuum in upper part which consist of Blue green algae called as “ANABINA AZOLLY” which fixes nitrogen from surrounding environment. There is symbiosis between Azolla & blue green algae in which nitrogen required for Azolla provided by blue green algae & algae requires some essential nutrients from Azolla. As far as use of Azolla for milch animal is concerned, now a day, there is much attention on the aspect of animal nutrition and Azolla. Azolla has abundant amount of proteins & vitamins. Azolla consist 25 to 35% proteins as well as Ferous, Copper, Magnesium in good proportion than that of ordinary fodder grasses, if we use Azolla in feed of milch animals then milk production will obviously high. It also studied that by using Azolla in feed of animals, there is decrease in cost of feed than that of whatever ordinary feeds & feedstuffs used in diet of animals. If we use EM along with Azolla then this also increase milk production. If we consider these practices on the basis of Dry Matter, then besides above mentioned proteins values, there is additional 10 to 15 % minerals & 7 to 10 % amino acids and bio active enzymes.

Sr No Fodder crops Yearly production(Tons/Hectare) Dry matter %age Protein %age
1 Hybrid Napier 250 50 4
2 Lucern 80 16 3.2
3 Cow pea 35 07 1.4
4 Jowar 40 3.2 0.6
5 Azolla 730 56 20

Production- Azolla is produced as follows (NARDEP) Under the 2 m pit then clean edges and base of pit should be smooth under the shade of tree, dig 2 in a level. Put plastic paper in pit then place silpaulin sheet above the plastic sheet. Put 10 – 15 kg fine soil after that spray slurry which contains 2kg cow dung& 30gm super phosphate in 10 liters of water. Add water o make the level of water of 10c.m..Then add 0.5-1kg of fresh Pure Azolla culture. After 10-15 days there is uniform growth of Azolla .afterward from each bed 500-600 gms of Azolla can be procured .Regularly after each 5days 1kg of Dung and 20gms of super phosphate to be added in each bed. Mixture of Picrolutopa also added at each week. It has necessary to harvest 200gms of Azolla per week. Also temperature of surrounding should not go above 25C,kee the water pH 5.5 -7 .At each month,5kg soil should be replaced and at the age of six month ,these bed should totally replaced with new beds. During this procedure, Azolla caught smell of cow dung and so for that animal can not eat Azolla when it fed solely. So what, care is taken to wash harvested Azolla then mix small amount in concentrates of animals initially. After animal has conditioned with smell of Azolla you can put Azolla solely as feed of cattle.azolla should be fed in the proportion of 1:1 as cattle feed (1.5 to 2 kg).Per kg production cost for Azolla is 60 to 65 paisa Vivekananda Kendra, Kanyakumari conducts regular training programme to educate farmers on techniques of cultivation of Azolla.

How does Azolla help in the improvement of agricultural soil?

This floating fern grows well in marshy land where paddy is cultivated. About 2 to 3 kg of Azolla is required per acre of land. First, the water should be allowed to stagnate in the land to be cultivated. Then Azolla should be sown. After fifteen days, these plants are mulched and integrated into the soil before transplanting of sapling. It degrades in about seven to ten days and provides nitrogen for the paddy.

After a week of transplanting of the paddy saplings, Azolla should be strewn in the paddy fields. Azolla will now grow as an intercrop. It takes about 21 days uniformly spreading into the entire area of the field. Once, this is achieved, please drain off the water and integrate the azolla into the soil. Repeat the process so that you can integrate the same for the third time when you are conducting the weeding operation for the second time.

The advantages of Azolla are:-

• It is a source of providing nitrogen to your plants at economical cost;
• It helps in increasing the yield at the time of harvest;
• As azolla is natural fern it helps in increasing the humus value of the soil which is good for soil health and enrichment;
• Since you are growing alongwith paddy crop, the percentage of weed in the field goes down considerably;
• Use of azolla is equal to use of green manure.