Organic Rice Production for Sustainable Ecosystem and Farming

Patnaik, Dr. Chitra

Abstract:
Field experiments were conducted during Kharif and Rabi seasons of 2007 and 2008 under organic farming and normal farmers’ practice at Nariso village of Niali of Khurda district of Odisha to study the implication of organic rice production for sustainable ecosystem and eco-friendly farming taking two indigenous varieties of rice (Oryza sativa Var. Solari and Oryza sativa Var. Khandagiri) and one High Yielding Variety (Oryza sativa Var.Sarala). It was found that the rate of growth was higher in all the varieties of rice cultivated in both Kharif and Rabi seasons by organic farming using organic manure, green manure and bio-pesticides in comparison to plant growth by normal farmers’ practice in which there was use of excess chemical fertilizers, pesticides and high cost machineries. The yield of grain also has shown significant indicators. In Kharif season in rice Var. Sarala and Var.Solari yield per hectare was found to be 4.5 mt and 3.4 mt in organic farming where as it was 3.8 mt and 2.5 mt in normal farmers’ practice. Similarly in Rabi season in rice Var. Khandagiri yield per hectare was 4.8mt which was higher in comparison to 3.9mt in normal farmers’ practice.

Keywords:Organic farming, rice, normal farmer’s practice, growth , sustainability.

1. Introduction:
The traditional system of agriculture has been in practice for more than ten thousand years, and has been recognized as more sustainable than any other system of agriculture. In course of time, during the late sixties of the last century, when the India faced shortage of food grains to feed the ever increasing population, Green Revolution was launched, which led to a significant increase in rice production, and India became a food grain (rice and wheat) surplus country. This achievement was primarily attributed to modernization of traditional practices with the use of high yielding varieties of seeds, chemical fertilizers and pesticides. But about forty years after, it was found that crop productivity and production has been affected adversely. There is great loss of soil fertility and biodiversitythus affecting various ecosystems and enhancing the rate of emission of green houses gases like CO₂, NO₂, thus leading to global warming and climate change. Due to various problems in modern agricultural technology, organic farming has again emerged as the viable alternative. Organic farming is a system of agriculture that seeks to maintain and improve land through natural and biological processes. It is farming of permanency and aimed at promoting plant, animal and human health ( Somani et al, 1992).

Organic rice production and farming is a holistic production management system, which avoids the use of synthetic fertilizers, pesticides, and genetically modified seeds. The organic farming system relies on crop rotation, use of crop residues, animal manures, off-farm organic wastes, green manures, bio-fertilizers, bio-pesticides to maintain soil productivity and tilth to supply plant nutrients and to control insects, pests and weeds thereby combating environmental pollution. This ultimately helps to maintain sustainable rice production and ecosystem. It is also cost effective, which helps our small and marginal farmers to sustain in rural areas of the country thereby maintaining their social, cultural and economic status. In view of this, the present paper focuses on the implication of organic rice production for sustainable ecosystem and farming.

2. Materials and methods:
A detailed survey was undertaken in the village Nariso taking 20 randomly selected families to study the socio-economic status of the people. It was found that 90% of the families were practicing modern agricultural system by using excessive chemical fertilizers and pesticides for years that had ruined the soil structure and fertility without producing sufficient crops. It was also found that 80% of the families were not accessing high cost implements. Only 10% of the families surveyed were using locally available organic manure, bio-fertilizers, bio-pesticides and traditional handmade tools and bullock plough.

In Kharif season two rice varieties were taken as test crops. One was high yielding variety (Oryza sativa Var.Sarala) that is a long duration crop of 150 days, and the second one was an indigenous but scented variety (Oryza sativa Var. Solari), which is a short duration crop of 135 days. In Rabi season Oryza sativa Var.Khandagiri was taken as test crop, which is an indigenous variety and a short duration crop of 110 days. Healthy seeds are locally available and collected from Loka Somabay Pratisthan (LSP), Nariso, an organization committed to the collection of indigenous rice seeds.

Field experiments were conducted by following both the Organic Farmer’s Practice and Normal Farmer's Practice (NFP) at Nariso village of Niali,Khurda,Odisha. The size of the fields chosen for both the practices as well as for each variety of rice is same namely 25 Cents (1/4th acre) of irrigated medium agricultural land.

2.1 Organic Farmer’s Practice:
The stages that an organic farmer follows and methods used in each stage are as follows.

2.1.1 Land Preparation:
It began with the thorough ploughing of land with Bullock plough followed by evenly spreading of Farm Yard Manure (FYM) on the whole field. Then Dhanicha (Sesbania aculeate) seeds (2.5 kg) were sown and on the arrival of monsoon puddling were done with 3-5cm of standing water in the field. When dhanicha plants attained 1-1.5ft heights, leaving some plants at the periphery of the field for collecting seeds for the next season, the young dhanicha plants along with weeds were threshed and mixed in the soil. This practice helps countering the weed problem in the field. Then neem oil cakes (12 kg) were spread evenly throughout field. Puddling up to 10cm depth makes the silty clay soil soft for the seedling to take root faster, to minimize the leaching of nutrients and thereby increasing the availability of plant nutrients. .

2.1.2 Nursery Raising:
The land for nursery raising was ploughed twice in dry condition and made wet with irrigated water. Then it was puddled in standing water (2-3cm deep) three to four times preferably at intervals of 5-6days. FYM, cow dung compost were applied uniformly at the time of first puddling. The field was then leveled perfectly after the final puddling. Then the sprouted seeds were broadcasted evenly on the soft mud and a thin film of water was maintained. After the emergence of first green leaf and completion of germination, the level of water was raised gradually and maintained at a depth of 2-3cm (Fig.2). The nursery was kept free from weeds and attack of pests and diseases. .

When the seedlings were at the 4-5-leaf stage (20-25days), the nursery was adequately irrigated and the seedlings were ready for transplantation. Care was taken during transplantation so that there was no damage to roots of seedlings. For this operation skilled male & female labourers were involved (Fig.3).

2.1.3 Transplantation:
Young, healthy seedlings at 4-5 leaf stage were transplanted which could establish themselves faster and grow better and give 15 percent more yield. In Kharif season, the seedlings were ready for transplantation within 20 to 25 days whereas in Rabi season, it took 30-40 days. The seedlings were planted at 20X10 cm spacing in labeled field with 1to2.5cm of standing water. Transplantation was done by both male and female skilled labourers (Fig.4&5).

2.1.4 Weeding:
Early weeding ( normally two weeks after planting) was done manually by male labourers. They wade through the wet field bare foot and trample the weeds down in the mud. Second weeding was done manually by hand after four weeks to maintain a weed free condition during growth period at 40-45 days after transplantation.

2.1.5 Water Management:
The water requirement of rice is higher as losses due to percolation and evapo-transpiration is more in submerged rice field. Soil compaction and puddling helped to reduce percolation losses. Considerable water content is possible as shallow submergence (2-5cm) is maintained from tillering to flowering and near saturation during other phases of growth.

2.1.6 Pest and disease management:
Spraying fresh cow urine diluted with water (1:5 dilution) was done after 3 weeks of transplantation to prevent outbreak of pest and diseases. Neem oil cakes were used during land preparation before transplantation to fumigate soil from different pathogens.

2.1.7 Use of Biofertiliser:
Biofertilisers like Azotobacter (1kg) and Azospirillum (1kg) inoculants were applied to soil during vegetative growth period (3weeks after transplantation) to maintain soil productivity especially nitrogen content of soil. These fertilizers suppress the growth of pathogenic bacteria in soil and increase the yield by secreting growth promoting substances.

2.1.8 Organic manures and nutrients management:
In Nariso Experiment , locally available organic manures like FYM, cow dung compost, crop residues, green manure (Dhanicha-Sesbasia aculeate) and Neem oil cakes were used as the source of major & minor plant nutrients like N,P,K,Zn, Fe, Mn etc. FYM and cow dung compost of about 2 quintal, 12 kg of Neem oil cakes, 2.5 kg of Dhanicha seeds were used during land preparation before transplantation. Bio-fertilizer like Azospirillum and Azotobacter (1kg each) were applied to the soil 45 days after transplantation as they help in atmospheric nitrogen fixation to improve the soil productivity. Handi Khata was also used as growth promoter to promote the growth of panicles and to reduce number of chaps (false grains).

2.1.9 Vermi-composting:
Vermi-composting in-situ was very much useful (Fig.1). As there was no use of chemicals (chemical fertilizer & pesticides) in organic farming it helped the earthworms to proliferate themselves in the soil there by enriching the soil fertility and plant growth with vermin castings.

2.1.10 Harvesting:
Harvesting was done at the proper time when the grains were getting golden yellow in colour: leaving few yellow green grains at the base of panicles, so that it prevents losses in yield because of the shedding of grains. Harvesting too early to maturity or too late was not done to prevent yield loss. Harvesting was done after draining away of water so that the field became dry to facilitate manual harvesting. Crops were cut with sickle mainly by male laborers and then kept in the field for 3 to 4 days for drying under sun. Harvesting was done when the moisture content of the grain was about 20-25 percent. Then the harvest was kept for drying to reduce the moisture content to 13-14 percent before milling.

2.1.11 Post Harvesting Process:
After harvesting gradual drying was undertaken on the shade for better recovery in the mills. Then threshing was done by beating the sheaves with light sticks on clean polythene sheet mainly by female labourers. The produce after threshing is known as rough rice, paddy or grain.

2.1.12 Milling:
Milling was done to separate husks, bran and germ from rough rice. The milled rice having polished kernel is white in colour. During the process of milling a certain percentage of grains get broken due to several factors. The whole rice (unbroken kernels) recovered after milling indicated the head rice recovery.

2.1.13 Storage:
Paddy was stored either for the use as seed for the next season or for milling. Proper storage of the produce was done (200kg grains:1kg neem oil cake) in the containers to avoid fungal attack, bad odour and bitter taste. Paddy was stored as needed in jute bags or in container made up of rope, straw, bamboo or mud otherwise known as Kothi. Rice (husked rice), either semi polished or polished was also stored in jute bags.

2.2 Normal Farmer’s Practice: The following are the stages that a normal farmer follows using chemical fertilizers, pesticides and mechanized implements.

2.2.1 Nursery rising:
Preparation of seedbed was done taking 4cents of land for each variety. Chemical fertilizers like DAP (2 kg) for phosphate, potash (1 kg) for potassium, Urea (2 kg) for nitrogen and chemical soil fumigant like Carbofuran (500gm) were applied to the ploughed land.

2.2.2 Transplantation:
An area of 25 cents was ploughed by bullock cart and irrigation water was filled in the field. Then chemical fertilizers like DAP (6kg), Potash (3 kg), urea (6 kg) were broadcasted on the field followed by puddling using Power tiller. Then in 2-3 days interval after settling of the soil, transplanting operation was completed.

2.2.3 Application of fertilizers:
After 15-20days of transplantation first dose of fertilizer (Urea-12kg) was administrated. Then after about two months of transplantation second dose of fertilizers like Urea (6kg), Potash (3 kg) and DAP (6 kg) were administered.

2.2.4 Weeding:
Weeding was done twice in the whole period. First weeding was done after about one month and second after about two months after transplantation by spraying synthetic weedicides usually Heptachlor or Round of ready.

2.2.5 Pest and disease control:
To control stem borer disease after one month of transplantation chemical pesticide like Carbofuran (1.5 kg) was administrated. Chemical pesticides like Bavistein (50 gm.) and Streptomycin (20 gm) were applied to control Rice Tungro disease, which is most commonly seen.

2.2.6 Water management:
The HYV rice variety consumed 30 percent more water in normal farming practice as compared to practices in the organic method. During puddling and transplantation 2”-3” water is needed, while after 15 days of transplantation 3”-4” of standing water is required. After 21 days of transplantation till 60 days the field needs to be flooded with 4”-5” of water because of use of chemical fertilizers.

3. Result and discussion:

Different parameters for both vegetative and reproductive growth periods like shoot length, root length, leaf number, tiller number, length of panicle, number grains per panicle, yield per hectare were analyzed in three locally established rice varieties viz., Solari, Sarala, and Khandagiri. It was found that in all the three varieties more or less similar trend was observed in both organic farmer’s practice and normal farmer’s practice (NFP) but vegetative growth was more pronounced in rice plants cultivated following organic farmer’s practice. (Table1-6, Fig.6, 7&8). There was also marked reduction in different yield related parameters in respect of all the three rice varieties in NFP in comparison to the same parameters in organic farming (Table1-6).

In organic farming water requirement is 30 percent less compared to chemical agriculture. Organic farming also does not require highly intensive irrigation infrastructure and thus spares pressure on precious resource water.

Further as it emerges, a farmer following organic farmer’s practice finds his yield as more remunerative than the farmer who follows normal farmer’s practice. For example, when organic Solari fetches Rs.1200 per quintal (p/q) inorganic Solari fetches Rs.1000 p/q. Similarly organic Sarala fetches Rs.900 p/q whereas inorganic Sarala fetches Rs.800 p/q. It is so because, as the study in Nariso indicates, the investment required to carry on chemical agriculture is relatively more than that is required for initiating organic farming practices particularly in rice production.

Sustainable agriculture involves more accurate execution of all production practices keeping quantity and quality of produces reasonably at good levels. Particularly sustainability of organic farming is a complicated process, as it must include various production, consumption, and ecological and socio-economic factors. Stockers et. al (1994) proposed evaluation systems based on nine parameters namely, productivity, profitability, quality of soil and water, energy efficiency, fish and wildlife habitats, quality of life and social acceptability, while IUCN international Assessment Team considered sustainability as basis of ecosystem and human well being ( IUCN 1996).Here focus was mainly on three criteria to have valid assessment of sustainable agri-system like ecological, economic and social factors, which was also suggested earlier by Rejntjes et al. ( 1999) .

3.1 Ecological criteria:

3.1.1. Organic manure and sustainability:
The organic sources of plant nutrients are organic manure like FYM , cow dung compost, green manure, crop residues, vermicompost, bio-fertilizers, which were applied not only to supply the plant nutrients but also to sustain the soil system. Besides neem oil cakes were also applied to the soil as soil fumigant. Organic manure forms the fundamental characteristics of organic farming. But the response of rice crops to organic manure mainly depends on degree of decomposition of organic residues, C:N ratio, time of application, type of soil.

3.1.2. Farm yard manure (FYM) :
FYM is the major organic manure most commonly used organic sources of plant nutrients. FYM used for the rice experiment was the decomposed mixture of cow dung and urine along with litter (bedding material) and left over material from fodder fed to cattle. Average national value of FYM is 0.5 % nitrogen, 0.2 % P₂O₅ and 0.5 % K₂O.An application of 25 ton of FYM per hectare supplies 112 kg of nitrogen, 56 kg of P₂O₅ and 112kg of K₂O with plenty of organic carbon and several micronutrients. FYM was applied to the soil about 3 to 4 weeks before transplantation so that there is presence of sufficient moisture in the soil and there will be enough time for its complete decomposition thus improving the soil structure (Yawalkar et al,1996). This is due to its contents of micronutrients and its ability to improve the soil tilth and aeration, to increase the water holding capacity of the soil and to stimulate the activity of micro-organisms that make the plant nutrients in the soil readily available to the crops. It was also found that the addition of FYM and the cereal residues results in improvement of total soil nitrogen (Bhardwaj and Gaur, 1985)

3.1.3. Cow dung compost:
Since the beginning of livestock husbandry, animal excreta have played an important role as valuable organic manure for soil improvement and optimum crop production. It is another method of augmenting the supply of organic matter from cow dung compost. Studies conducted in India and particularly in Orissa have shown that cattle manure can be produced by Indore method (Howard and Wad, 1930) from waste material of various kinds such as cereal straws, crop stubbles, litter, urine soaked earth from cattle sheds, and cow dung. Composting was done completely so as to lower the carbon: nitrogen ratio to about 12:1, which was found by Palaniappan and Annadurai, 1999.

Another important factor might be the timely application of organic manure and cow dung to soil which was found to be more effective in supplying plant nutrients and maintaining soil organic matter thereby sustaining the agricultural system as earlier reported by Hazra (2007).

3.1.4. Crop residues:
Crop residues are bulk of crop biomass left after harvesting the crops. In case of rice, a voluminous amount of stalk and stubbles is used as supplementary source of nutrients after composting in the experimental field. It was found that stubble of rice of 4200 kg per hectare add organic matter of 1764 kg per hectare, nitrogen of 17.6 kg per hectare, phosphorus of 2.9 kg per hectare and potassium of 25.2 kg per hectare (Bisoyi , 2003).

3.1.5. Vermicomposting :
Vermicomposting is a method of making compost with the use of earthworms which generally live in soil, eat biomass and excrete it in digested forms. In this research project vermicomposting was done in experimental field as earthworms were grown well without any cost. Thus naturally produced vermicompost was used as source of organic manure rich in macro and micro nutrients, vitamins, antibiotic growth hormones, bio-pesticides and immobilized micro-flora. The nutrients present in vermicast are readily soluble in water which can be easily up taken by plants .In this type of composting earthworms act as the natural bioreactor which not only convert waste organic matter present in the field but also harness the beneficial soil micro-flora thereby maintaining the soil physical, chemical and biological properties to sustain life. Availability of earthworms in the soil have always promoted plant growth probably due to presence of plant growth hormone like cytokinin and auxin in Nariso case study in rice which showed increase in plant growth and ultimately plant yield as also reported by several scientists ( Gaur,1992 ; Shinde et al ., 1992 ) .

3.1.6. Bio-fertilizers:
Bio-fertilizers are the products containing living cells of different types of microorganisms like Azotobacter and Azospirillum and green plants which have an ability to mobilize nutritionally important elements from non usable to usable form through biological processes. Bio-fertilizers are also environment friendly, economic, non agricultural input which significantly improves soil fertility and plant nutrition thus useful in sustainable agriculture as reported earlier by Gupta (2007)

Green manuring in situ is a practice of ploughing un-decomposed green plant tissues into the soil for the purpose of improving physical structure as well as fertility of soil. It increases the organic content of soil which enhances the nutrient availability and tilth of soil and restricts the growth of weeds .It also helps to control pests and increases the biological activities in the soil. In Nariso experiment, leguminous green manure crop like Dhanicha (Sesbania aculeata), which is locally available were grown particularly during monsoon before the main rice crop and buried in the same field in the tender stage which is to be green manured. After decomposition they increase the nutrient availability mainly nitrogen content in soil by fixing atmospheric nitrogen which was also found by Howard,1940,Singh, 1974 and Mirchandine & Khan,1952 . Green manuring also adds organic matter and return the plant nutrients taken up by the crop from the deeper layer to the top soil thus increasing availability of nutrients like P,K,Ca,Mg,Fe,S etc for main crop and conserve plant nutrients that would otherwise be lost by leaching thus sustaining agricultural system.

3.1.7. Weed management in rice field:
Weeds are the plants, which grow where they are not wanted. They usually compete with rice crops for water, soil nutrients, light, space thus reducing the crop yield. They also harbor harmful insects, pests and microorganisms. In this project before weed control, prevention was taken during seed selection so that crop seeds were not contaminated with weed seeds. Weeds were usually controlled by mechanical methods like hand weeding, hoeing, and tilling using physical energy. But it has been found that hand weeding was the most efficient method though it was time consuming with high labour cost. Tillage was also done by ploughing to control annual weeds. As there was no use of synthetic weedicides, it helped in restoring the soil structure and fertility which would ultimately maintain a sustainable ecosystem without causing any toxic effect on the environment.

3.1.8. Biological control of pest:
Going through the indigenous knowledge of some skilled farmers of Nariso village it was found that pests and major diseases like stem borer, leaf folder, panicle blast, sheath rot in rice is well controlled by biological means. In this project pest outbreak was checked by different means like soil solarisation and green manuring by dhanicha, adoption of crop rotation, hand weeding for weed removal during seedling and nursery stage, soil amendment with neem cake for soil inoculants during transplanting. To eradicate pests in rice plant, locally available natural pesticides like fresh cow urine and neem oil were used as foliar spray which have low toxicity to human beings and other animals and do not persist in the environment thus sustaining the environment. A total of 147 species of insects have been reported to be sensitive to neem alone (Tanwar et al.,2006).Further during the period between transplanting and maturity care was taken to avoid water stagnation and even dry condition as these favour disease development in rice crop. Foliar spray of fresh cow urine diluted with water (1:1) was done for suppression of bacterial blight.

3.1.9. Organic seed production and sustainability:
From the present project work it was found that after harvesting, the rice grains were either processed and stored for consumption or could be preserved as indigenous seeds for the next season. By this practice the farmers of Nariso village do not have to depend upon external source to buy seeds. They can also use healthy, viable and disease free seeds without any further cost which helped to restore the sustainability in organic rice production. At the same time indigenous seeds of different rice varieties could be stored for years together without hampering the crop yield which also helped to sustain the socio economic condition of marginal and sub-marginal farmers of Nariso village.

3.2 Economic and Social criteria:
A comparison in terms of economic factors, between organic and inorganic farming practices, suggests organic farming to be preferable as it progressively reduces expenditure on farming when the practice is sustained over a period of time. Farming inputs such as seeds, bio- fertilizers, bio-pesticides when become locally available, dependence on external market gets reduced ultimately strengthening the farmers’ economy. No spending of foreign exchange on import of agricultural inputs such as seeds, fertilizers, pesticides and farming equipment becomes any more necessary.

Human labor and locally available farming equipment once again come to center stage by reducing dependence on machines. An organic economy grows in the locality having nothing or very little to do with external markets except that of disposing of the surplus which also brings more resources as the demand for quality or healthy food grains grows up. Organic farming does also turn farming in to a collective and cooperative activity by encouraging mutual cooperation and sharing that covers seeds to yields. In the organic farming structure, the severity of unutilized labour force is much reduced, and so also migration to alien places in search of work. An integrated and holistic living culture emerges centering around a sustainable and eco friendly farming culture.

4. Conclusion:
The Nariso study does provide us the scope to take the experiment forward. From this experiment one learns that if organic farmer’s practice is followed in a greater scale, then farming, particularly rice cultivation, becomes economically viable while ecologically sustainable. Such practice not only spares farmers from depending on external inputs either in the form of technology or finance, it ensures their freedom and self-respect. The Nariso study also proves that the experiment is scientific as organic farming practices involve more accurate execution of production practices. It does also give importance to qualitative inputs in agriculture which results in bringing quality in production without compromising the quantitative aspects of production out puts. In the long run slow release of plants nutrients would help in the improvement and restoration of physical and bio-chemical conditions of soil, in sustaining the yield of different varieties of rice and other crops, in reducing air, water and soil pollution and related health hazards, and ultimately in saving the environment.

Figures

Acknowledgement:

The author gratefully acknowledges the financial support the study received from University Grants Commission(UGC), laboratory support extended by Principal,Kamala Nehru Women’s College, Bhubaneswar, and the invaluable inputs received from the organic farmer Shri Natabar Sarangi and his associate Shri Yubaraj Swain in the study area.

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