during samba (August-December) season of 2012 and 2013 to study the effect of different sources of organic manures in comparison with INM and RDF on nutrient uptake and soil properties in rice (Oryza sativa L.). The experiment consisted of fourteen treatments which were laid out in Randomized Block Design, replicated thrice and SRI method of planting was adopted during both the years. Among fourteen treatments, four treatments with different organic manures at 100 per cent RDN on equi nutrient basis (farm yard manure, vermi-compost, poultry manure and (Dhaincha) green manure) another six treatments consisted of 50 per cent combination of each manure, one treatment with 1/4 th combination of all the manures and one absolute control (without organic or inorganic). These treatments were compared with the recommended dose of fertilizer (RDF) and integrated nutrient management practice (RDF + Dhaincha). Higher N, P and K uptake was observed with INM practice followed by RDF. Among the organic treatments, 100 per cent RDN through green manure resulted with higher nutrient uptake followed by 25 per cent RDN through each organic manures. Lower nutrient uptake was observed with absolute control where no fertilizers / manures received during both the years of study. The soil available N and P balance was positive with the INM treatment (85.0 and 5.10 kg ha-1) at the end of two year of cropping sequence. Among the organic treatments, 100 per cent RDN through green manure recorded the highest N balance (46.0 kg ha-1) followed by 25 per cent RDN through each organic manures (42.0 kg ha-1) at the end of the cropping system (2012-14). Similarly, the highest P balance was recorded with 25 per cent RDN through each organic manures (3.1 kg ha-1) and which was followed by 100 per cent RDN through green manure (3.0 kg ha-1) at end of the two years of cropping sequence. The least N and P balance was noticed with absolute control (-4.0 and-2.5 kg ha-1) at the end of cropping sequence. Invariably, all the treatments recorded net negative K balance in both the years of cropping sequence.

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SUMMARY :Field experiments were carried out at Tamil Nadu Agricultural University, Coimbatore, India during Samba (August-December) season of 2012 and 2013, and summer 2013 and 2014 with rice fallow green gram to study the effect of different sources of organic manures in comparison with RDF and INM on growth, yield, economics and nutrient status in rice-green gram cropping system. The experiment consisted of fourteen treatments which were laid out in Randomized Block Design, replicated thrice and square planting with 25 x 25 cm spacing was adopted during both the years experimentation. The gross return per hectare during 2012-2013, extended from Rs. 62,971 to Rs. 1,14,730 for the ricegreengram cropping system. The growth parameters such as productive tillers m -2 and the yield attributes like dry matter production, grain and straw yield of rice was recorded during both the years of the cropping system. The system productivity was worked out for the entire period of the cropping system. The nutrient balance status (N, P and K) was worked out at the end of the entire cropping system. The N and P balance at the end of the cropping system was positive in all the treatments except the absolute control, whereas the negative K balance was worked out in the entire cropping system. Higher gross return (Rs. 1,14,730) and net return (Rs. 68,245) were associated with the INM treatment (T 14 ) with the grain yield of 6235 kg ha -1 and it was corresponded to that observed with T 5 viz., 100% RDN through green manure (T 5 ) with the grain yield of 5084 kg ha -1 for gross return (Rs. 1,12,979) and net return (Rs. 66,978). During 2013-2014, the gross return and net return of the rice-greengram cropping sequence varied from Rs. 63,817 to Rs. 1,17,175 and from Rs. 32,385 to Rs. 70,690, respectively. The INM treatment (T 14 ) recorded with the grain yield of 6270 kg ha -1 and the higher gross return (Rs. 1,17,175) and net return (Rs. 70,690) and which was comparable with 100% RDN through green manure (T 5 ) with the grain yield of 5140 kg ha -1 and the gross return of Rs. 1,15,380 and the net return of Rs. 69,340, respectively. The lowest gross return was registered with the absolute control (T 1 ) (Rs. 63,817) and net return (Rs. 32,385) with the grain yield of 3602 and 3646 kg ha -1 during the cropping sequence

SUMMARY :Field experiments were carried out at Tamil Nadu Agricultural University, Coimbatore, India during Samba (August-December) season of 2012 and 2013 to develop better organic nutrient management package for the rice variety CO(R)48 under site specific organic farming condition in comparison with RDF and INM. The field experiment consisted of fourteen treatments which were laid out in Randomized Block Design, replicated thrice and square planting (25 x 25 cm) was adopted during both the years. Among fourteen treatments, four treatments with different organic manures at 100% RDN on equi-nutrient basis [farm yard manure, vermicompost, poultry manure and (Dhaincha) green manure] another six treatments consisted of 50 % combination of each manure, one treatment with 1/4 th combination of all the manures and one absolute control (without organic or inorganic). These treatments were compared with the Recommended Dose of Fertilizer (RDF) and Integrated Nutrient Management (INM) practice (RDF + Dhaincha). The nutrient content(N, P and K) of the different organic manures used in the experiment was given. The important growth parameters like tillers per square meter, number of panicle per square meter, total grains per panicle, thousand grain weight and grain yield of rice were recorded. The root length, root dry weight, root volume, and N, P and K uptake of rice at harvest was recorded. The rice quality parameters like milling percentage, hulling percentage, head rice recovery, length breadth ratio, volume expansion ratio, amylose and protein content in percentage were recorded. The INM imposed treatment recorded better growth parameters and yield attributes of rice and N, P and K uptake of rice at harvest, whereas, among the organic treatments, 100% RDN through green manure followed, by 25% RDN through each organic manures combination recorded more growth and yield attributes and important quality parameters and N, P and K uptake of rice at harvest in both the years of experimentation.How to cite this article : Alagappan, S., Venkitaswamy, R. and Mariappan, G. (2017). Developing better organic nutrient management package for the rice variety Co(R)48 under site specific organic farming condition in comparison with RDF and INM practices. Agric. Update, 12(TECHSEAR-1) : 154-172;

. To study the soil physico-chemical properties, nutrient balance and yield in lowland rice-greengram cropping sequence under organic farming. The test variety of rice CO(R)48 and the greengram variety (Co 6) were used in the two year cropping sequence under site-specific organic farming condition in comparison with RDF and INM. The field experiment consisted of fourteen treatments which were laid out in Randomized Block Design, replicated thrice and square planting (25 x 25 cm) was adopted, the same layout was maintained for residual rice fallow summer greengram in both the years of study. The soil physical properties like bulk density, particle density, per cent pore space and water holding capacity. Similarly, the soil chemical properties like soil pH, electrical conductivity (EC) and soil organic carbon (OC) content was also recorded after harvest of rice and after the harvest of greengram in the entire cropping sequence. The grain and straw yield of rice and greengram were recorded. Organic carbon content of soil was significantly increased with 100 % RDN through green manure and it was followed by all the other organic treatments. The INM practice and recommended NPK fertilizers were noticed with lesser organic carbon content and the absolute control recorded with the lowest soil organic carbon content in both the years of study. The soil nutrient contents like soil available NPK, uptake of NPK by the crop and the nutrient balance (NPK balance) in the rice-greengam cropping sequence were also recorded. The less bulk density and more per cent pore space and water holding capacity values were recorded in all the organic treatments and the INM imposed treatment recorded at par values of the 100% RDN through green manure treatment and the higher bulk density and lesser per cent pore space and water holding capacity was recorded with RDF treatment. The soil available NPK and uptake of NPK at harvest of rice, was higher recorded with INM practice followed by RDF treatment, whereas among the organic treatments, 100% RDN through green manure followed, by 25% RDN through each organic manures combination recorded more soil available and uptake of major nutrients in both the years of experimentation. Similar trend was noticed in grain and straw yield of rice and greengram during both the years of study. The N and P balance at the end of the cropping system was positive in all the treatments except the absolute control, whereas the negative K balance was noticed in the entire cropping system.