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After the green revolution, India became self-sufficient in the production of food grains, but to meet the future need of food grains for the burgeoning population, extensive cropping was practiced which affected the soil health. Need for a second green revolution has been felt by Scientists and policy makers in the recent years in India. To achieve this, it is essential to develop technologies having greater scope for improving soil fertility and productivity. Maintenance of soil fertility and productivity is the dire need of present day farming as the level of soil organic matter is getting depleted due to over use of inorganic fertilizers, lesser use of organic manures, mono cropping, imbalanced fertilizer use etc. The area under multiple nutrients deficiencies are also increasing in recent years. As a result of degradation and depletion of soil fertility, agricultural production in many region is now failing to show positive response to increasing agricultural inputs. 

Around the world, nearly one billion people live along the 3,12,000 Km long coastline. The Indian coastline runs around 8,129 Km distributed along nine coastal states, two groups of islands and two union territories. The coastal ecosystem of India forms a very valuable resource community, supporting the livelihood security of several million rural poor and also contributing the national economy in a large measure. The latest estimates by National Bureau of Soil Survey and Land Use Planning (NBSS & LUP), Nagpur, India, using Global Assessment of Soil Degradation (GLASOD) guidelines indicate that the coastal area in the country is spread over an area of 11.8 million hectares (Mishra, 2005). Yadav et al. (1983) have reported about 3.1 M ha and 2.1 lakh ha of coastal salinity in India and Tamilnadu respectively.

The coastal salt affected soils are low in productivity due to various soil fertility constraints that affect the crop growth and yield. The high salt content &/or high pH cause changes in solubility, availability and efficiency of plant nutrients, besides deteriorating the physical condition of soil. The soil biology (microbial population and enzymatic activities) also severely affected in these salt affected soils. The bio-resources are known to improve soil physical, chemical & biological properties of the soil. The maximization of rice production and considerable improvement in quality and composition of rice in coastal salt affected soil with the use of bio-resources have been reported by several research workers.

It is generally observed that N, P and Zn content in soil decreases with increasing soil salinity. Nutrient imbalances created by continuous use of chemical fertilizers, particularly nitrogenous fertilizer alone, combined with sub optimal rates of other nutrients or total omission of other nutrients are the primary causes for unsustainable yields of crops in saline soil. A sustainable approach for nutrient management in salt affected soils should therefore include balanced use of organic, inorganic and biological sources of nutrients (Bandyopadhyay and Rao, 2001). Organic amendments are known to facilitate the reclamation of sodic soils and better nutrition of crops (Anand swarup, 1992).

Experiments at Central Soil Salinity Research Institute (CSSRI), Kamal, India showed that alkali soils are not always high in available P and rice and wheat significantly responded to addition of P (Pathak et al., 1975). The availability of phosphorus in soil either native or added is limited by fixation and precipitation mechanisms. The organic acids released during decomposition of organic matter influences the soil pH, form stable complexes with cations responsible for P fixation and thus increases the availability (Tiwari et al., 1980). The use of bulky organic manures (Maurya and Ghosh, 1972; Chaudhary et al., 1981) and green manures (Prabhakar et al., 1972; Sharma et al., 2000) has been found very beneficial for P management of saline and alkali soils as these improve the soil physical condition and the availability of soil phosphates.

Potassium availability in most of the coastal salt affected soils of India is rich except when the soils are low in clay content (Bandyopadhyay et al., 1985). Plants grown under high salinity may show K deficiency due to the antagonistic effect of Na on K absorption and / or disturbed Na / K ratio. Under such conditions application of K is also known to reduce the adverse effect of salinity and sodicity on crop growth (Qadar, 1995). Singh et al. (1980) reported that the addition of FYM increased the K concentration in the soil. Swarup (1987) reported that the incorporation of green manure increased the available N, P and K status of the soil. Available P and K remarkably increased to a tune of 30 and 44 per cent respectively by the application of coir waste (Santhi et al., 1991).

Secondary nutrients Secondary nutrients includes Calcium, magnesium, and sulfur. Crop plants requires secondary nutrients in moderate quantity for crop growth and yield. Their requirement by plant is less than the macro nutrients. Sulphur and Magnesium requirement of crops are very similar to the Phosphorus needs. Calcium is required in higher amount than Phosphorus. Calcium and magnesium are mostly deficient in acid and alkali soils. In India S deficiencies are found in almost 40 per cent of the cultivated soil. Under intensive cropping system, the use of higher amount of nitrogenous fertilizer without secondary and micro nutrients and lesser use of organic manures are the major reason for the secondary and micro nutrient deficiency in soil.

The bio-resources application in the soil is known to improve the biological properties of the soil. Several earlier reports show a spur in microbial populations or increased microbial biomass carbon and the enhanced enzymatic activities with the incorporation of bio-resources in soil (Perucci, 1990; Goyal et al., 1993; Bonde et al., 2004). Microbial populations Indigenous microbial populations in soil are of fundamental importance for an eco system functioning, through determining nutrient cycling, organic matter decomposition and energy flow (Doran and Zeiss, 2000).

In the global scenario, the increasing energy crisis and consequent escalation of chemical fertilizer prices along with increasing risk associated with soil degradation have reviewed interest in bio-resources for attaining soil health and sustainable crop production. The use of organic manures, bio-fertilizers and chemical fertilizers will augment the efficiency of combined application of nutrients to maintain a high level of soil productivity and rice production (Thakuria et al., 1991; Prasad et al., 1995). Several experimental evidences showed that the combination of various bio-resources with chemical fertilizers improved the rice production in sustainable way (Roy and Jha, 1987; Subba Rao, 1995; Mahapatra et al., 1997; Suresh et al., 2001).

Organic manures Anand Swarup (1992) stated that application of green manures along with rice husk increased the concentrations of N, P, Zn, Mn and Fe and decreased the Na concentration of rice in a reclaimed sodic soil. Kolambe and Patel (1994) reported that application of organic amendments along with phosphorus increased the uptake of phosphorus at different growth stages of rice. Talashilkar and Chavan (1997) reported that incorporation of 10 t of Glyricidia ha-1 and application of 100 per cent RDF recorded the highest total N uptake by rice over three successive years. Mishra and Sharma (1997) found that application of 100 per cent NPK + 10 t FYM ha-1 resulted in highest total uptake of NPK by rice. Mahapatra etal. (1997) revealed that application of 80 kg N ha-1 through green manure alone or through combined use of green manure and urea increased the total uptake of N by rice over application of fertilizers alone.

The uptake of Mg by rice plant was highest when fertilizer was applied in combination with vermicompost (Jadhav etal, 1997). Pattanayak etal. (2001) also reported the highest Ca uptake in the treatments that received green manuring of dhaincha. Sriramachandrasekharan (2001) who reported the highest Fe uptake of rice with green manuring of Sesbania aculeata. Debele et al. (2001) reported that the application of FYM enriched with 10% rock phosphate + gypsum with PSB and PSF @ 500 g inoculums t-1 of FYM increased the nutrient uptake of maize. The higher nutrient uptake of 227 kg N ha-1, 59.5 kg P ha-1 and 227 kg K ha-1 recorded with the application of enriched FYM @ 2 t ha-1.

Acharya, C.L., S.K. Bishnoi & H.S.Yaduvanshi (1988). Effect of long term application of fertilizers & organic and inorganic amendments under continuous cropping on soil physical and chemical properties in an alfisol. Indian J. Agric. Sci., 58: 509-516. Adane A., Gebrekidan H., Kibret K. Effects of treatment application rates (fym and gypsum) on selected chemical properties of saline sodic soils under water limited condition in eastern lowlands Ethiopia. Forest Res Eng Int J. 2019; 3(3): 106113. DOI: 10.15406/fteij.2019.03.00086 Aggelider, S.M. & P.A. Londra (2000). Effect of composts produced from town wastes & sewage sludge on the soil physical properties. Bioresour. Technol., 71: 253-259. Ahmed, K., Qadir, G, Jami, A.R., Nawaz, M.Q., Rehim, A., Jabran, K., Hussain, M. Gypsum and farm manure application with chiseling improve soil properties and performance of fodder beet under saline-sodic conditions. Int. J. Agric. Biol., 2015 17: 1225-1230.