Organic Basmati Rice Production Technology

As explained above, Basmati rice has a good market locally as well as export purpose and this market may be further exploited if such rice is grown organically. Production technology of organic Basmati rice has been developed at the Centre for Conservation and Utilization of Blue Green Algae (CCUBGA), IARI during last six years and it has been verified at farmer's fields also. This technology package is described hereunder:

This production technology can be adopted by the farmers depending upon availability of resources and climatic condition etc. For organic cultivation of bas mati rice producers must follow the National Standards for Organic Production (NSOP), which are the guidelines recommended by Agricultural and Processed Food Products Export DevelopmentAuthority (APEDA), Govt. of India. In following the NSOP, availability of production technology/resources is the big question. Research results have indicated that application of organic amendments like Azolla, BGA, FYM, Vermicompost and green manuring with Sesbania or green gram can give optimum yield ( around 4.2 ton/ha) of basmati rice (Pusa Basmati-1 or Pusa Basmati 1121). The combined application of organic inputs like Azolla @ 1.0t/ha, BGA @ 2.0 kg/ha, FYM@ and Vermicompost @ 5.0 tlha each gave the grain yield of 4.2 t/ha which was at par with the yield recorded under recommended dose of chemical fertilizer(NsoP4oK4o) application. Green manuring of green gram was also taken up to increase organic content in soil and get pulse for consumption.

NUTRITIONAL INPUTS FOR ORGANIC RICE FARMING

The food that plant take and soil organisms need to do their job comes in the form of organic matter. There are many effective nutritional practices like green manuring, use of biofertilizers, Azalia sp., use of crop rotation, incorporation of crop residues etc. The green manuring and biofertilizers not only add nutrients such as nitrogen to the soil, but also help prevent weeds and increase organic matter to feed soil microorganisms. In organic farming we add the natural minerals that plants need to grow and that help improve the soil's consistency. The organic inputs applied for organic rice production are described below:


Blue Green Algae (BGA): BGA are the pioneer colonizers both in hydrosphere and xerosphere. These organisms have been found to synthesize 0.8x1 011 tonnes of organic matter, constituting about 40 percent of the total organic matter synthesized annually on this planet. BGA constitute the largest, most diverse and widely distributed group of prokaryotic microscopic organisms that perform oxygenic photosynthesis. These are also known as cyanobacteria. These are widely distributed in tropics; and are able to withstand extremes of temperature and drought. The significance of the abundance of BGA in Indian rice soils has been well recognized. Multilocational trials conducted under varying agro-c1imatic conditions have indicated that the algal inoculation could save 30 kg N/ha, however, it depends upon the agro-ecological conditions (Table 1). BGA has been reported to reduce the pH of soil and improve upon exchangeable calcium and water holding capacity. The recommended method of application of the algal inoculum is broadcasting on standing water about 3 to 4 days after transplantation. After the application of algal inoculum the field should be kept water logged for about a week's time. Establishment of the algal inoculum can be observed within a week of inoculation in the form of floating algal mats, more prominently seen in the afternoon.

Azolla: A floating water fern 'Azolla' hosts a nitrogen fixing BGA Anabaena azollae. Azolla contains 3.4% nitrogen (on dry wI. basis) and add organic matter in soil. This biofertilizer is used for rice cultivation in different countries viz. Vietnam, China, Thailand, Phillipines. There are six species of Azolla viz. A. caroliniana, A. nilotica, A. mexicana, A. filiculoides, A. microphylla and A. pinnata. Azolla plant has a floating, branched stem, deeply bilobed leaves and true roots which penetrate the body of water. The leaves are arranged alternately on the stem. Each leaf has a dorsal and ventral lobe. The dorsal fleshy lobe is exposed to air and contains chlorophyll. It grows well in ditches and stagnant water. Azolla can be easily grown throughout the year in India if water is not a limiting factor and climatic conditions are favourable for its growth. This fern usually forms a green mat over water. Azolla is readily decomposed to NH4 which is available to the rice plants. Field trial have shown that rice yields increased by 0.5-2 tlha due to Azolla application. In India and China, about 20 and 18% increase in rice yield, respectively has been reported due to Azolla application.

Azotobacter: N2-fixing free-living bacteria like Azotobacter sp. can fix atmospheric nitrogen in cereal crops without any symbiosis. Besides fixing N2 they also increase germination and vigour in young plants leading to an improved crop stand. They can fix 15-20 kg/ha nitrogen per year. Azotobacter sp. also has ability to produce antifungal compounds against many plant pathogens (Table 1).
Azotobacter can biologically control the nematode diseases of plants also.

Phosphorus-solubilizing bacteria (PSB): Phosphorus is the vital nutrient next to nitrogen for plants and microorganisms. This element is necessary for the nodulation by Rhizobium and even to nitrogen fixers like Azolla, Azotobacter and BGA. The phospho¬microorganism mainly bacteria and fungi make insoluble phosphorus available to the plants. It can increase crop yield up to 200-500 kg/ha and thus 30 to 50 kg super phosphate can be saved. Most predominant PSB belong to the genera Bacillus and Pseudomonas. At present PSB is most widely used biofertilizer in India. PSB can reduce the P requirement of crop up to 25%.

Organic manures: Commonly available and applied farm yard manure (FYM) and vermicompost etc. are generally low in nutrient content, so high application rates are needed to meet crop nutrient requirements (Table 2). However, in many developing countries including India, the availability of organic manures is not sufficient for crop requirements; partly due to its extensive use of cattle dung in energy production. Under these limitations, organic manures like FYM and vermicompost may be used in combination with other inputs for organic production. Table 2. Composition of FYM Vermicompost Sl.No Nutrient Vermicompost FYM 1 N(%) 1.65 0.75 2 P2O5 0.05 0.17 3. K20 0.80 0.55 4. Calcium (%) 0.44 0.91 5. Magnesium (%) 0.15 0.19 6. Iron (ppm) 175.2 146.50 7. Manganese (ppm) 96.51 69.00 8. Zinc (ppm) 24.43 14.50 9. Copper (ppm) 4.89 2.80 10. C:N ratio 15.50 31.28 Green Manuring: Green Manuring with Sesbania, cowpea, green gram etc are quiet effective to improve the organic matter content of soil but use of green manuring has declined in last few decades due to intensive cropping and socio-economic reasons. To built up optimum organic carbon level in soil green manuring with Sesbania or green gram must be included in organic production. Considering the constraints in availability of some nutrients in appropriate quantity for organic farming International Federation of Organic Agriculture Movements (IFOAM) and Codex Alimentarius have approved the use of some inorganic sources of plant nutrients like rock phosphate, basic slag, rock potash etc. in organic farming systems. These substances can supply essential nutrients and may be from plant, animal, microbial or mineral origin and may undergo physical, enzymatic or microbial processes and their use does not result in unacceptable effects on produce and the environment including soil organisms.

RESEARCH RESULTS

Research result of six years (2003-08) have indicated a significant enhancement in grain yield of basmati rice over absolute control due to the application of different bio¬inoculants applied alone or in combinations was recorded. The rice grain yield increase was found to be ranging between 13 to 30% due to single organic amendment. However, yield increase over absolute control was 119% when all four bio-inoculants were applied together. The mean rice grain yield (4.20 tlha) obtained under combined application of four bio-inoculants was the statistical at par with the yield recorded under recommended dose of chemical fertilizer application (4.37 tlha)


The rice grain yield decreased by 17.7% over recommended dose of chemical fertilizer application during first year of organic farming and this decrease was only 7.6% during the second year. However, third year onward grain yield under organic farming was almost same as under conventional farming (Table 3). There was no serious attack of any insect pest or disease in organically grown rice crop during 2003-07 seasons. But during kharif 2008 season, there was an over all reduction in rice yield in all the treatments over previous years due to the epidemic of white backed plant hopper (WBPH). However, when this yield was compared with epidemic of WBPH in other experiments at IARI and northern India, then it was noted that the reduction in grain yield of rice under organic farming was much less as compared to the rice managed through traditional system. Similar observations were recorded through on-farm trials conducted on organic basmati rice cultivation. Soil microbial population (Actinomycetes, Bacteria, Fungi and BGA) was found to be continuously enhanced due to the application of bio-inoculants in comparison to absolute control as well as recommended fertilizer application that in turn resulted in a notable enhancement in soil dehydrogenase enzyme activity. Soil organic carbon contents were also found to be continuously enhanced over the years due to the organic farming practice over control as well as chemical fertilizer application. Rice grain analysis for iron, zinc, manganese and copper nutrients showed a significant increase iron, zinc and manganese contents in the treatments having 3 or 4 bio-inoculants over control treatment. On-farm Testing on Organic Rice: The results of experiment on organic rice farming were verified/demonstrated through on-farm testing (OFT) conducted at villages of U.P and Haryana. The treatment showing best performance at IARI farm was compared with farmers' traditional fertilizer management practice. Two rice varieties 'Pusa Basmati-1 'and 'Pusa Sugandh-4' were used in OFTs. Results showed that the growth and grain yield (4.00 and 4.20 tlha from 'Pusa Basmati-1' and 'Pusa Sugandh-4', respectively) of organically grown both the rice varieties was at par with the same varieties grown under traditional fertilizer management. Economic analysis of organic rice production indicated that farmers can get higher net returns through organic farming if they are paid premium price of their produce for which they deserve.