Browsing by Author "Betty Bastin"

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Aerobic composting and enrichment of ayurvedic waste
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 2003) Lekshmisree, C S; Betty Bastin
Assessment of soil degradation and water quality in areas of small scale brick production and management of the degraded soil
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 2019) Sophia Baby; Betty Bastin
The utilization of clay for construction of habitations and buildings dates back to the period of ancient civilizations. Even though centuries had passed and civilizations changed, the basic raw material for brick production remained the same. Brick production requires fine clayey loam soil with plenty of water supply. With the increasing demand for construction material, clay mining had shifted from river banks to fertile agricultural lands. This change in land use had resulted in the deterioration of soil health and decrease in crop production. The entry of large number of small scale brick production units is causing irreversible damages to the soil, hydrology and ecosystem. Hence, this study was taken up to characterise the desurfaced (mined) soils and water resources and to identify suitable management methods of these soils. A comprehensive survey was conducted at Alathur Taluk of Palakkad District to identify locations with resurfaced soils. Soil and water samples were collected from 11 locations including a control location without mining activities during August to September, 2017. A total of 88 soil samples (eight samples per location) and 11 water samples (one sample per location) were collected for the study. Both soil and water samples were analysed for various physico- chemical properties. Biological properties of soil samples were also analysed. The physical properties of soil such as temperature and bulk density were found to be higher in desurfaced soils when compared to control. The water holding capacity, porosity and moisture content were found to be reduced in desurfaced soils. The texture of the soil changed from clay loam to sandy loam. The organic carbon content of desurfaced soils were in the range of 0.08 – 0.46 per cent with a reduction of 61 per cent when compared with control soil. The content of available nitrogen, phosphorus and potassium were also reduced to the extent of 43.70, 74.50 and 43.36 per cent respectively. The available magnesium content was found to be lower in desurfaced soils (55.6 per cent reduction). The content of plant available micronutrients (Fe, Mn, Cu and Zn) and heavy metals (Ni, Cr and Pb) were high in desurfaced soils. The presence of earthworms (13 nos. per m2) and termite mound were observed only in the xi control soil. The microbial biomass carbon and dehydrogenase enzyme activity were highly reduced in desurfaced soils. Water samples were also affected by small scale topsoil mining activity. The pH, electrical conductivity and TDS were in the safer limits for all water samples. The concentrations of sodium (W1 andW10) and calcium (W1 andW5) in certain water samples collected from mined areas were high and they were above safe limits to be used for irrigation purposes. Similarly the higher levels of nitrate, phosphate, bicarbonate and chloride in water samples from mined areas denote the possibility of the water bodies being polluted by mining activities. Based on the status of organic carbon and major nutrients, the soil with the lowest nutrient status (S5) was selected for pot culture study. The pot culture study was conducted with chilli (var. Anugraha) as the test crop. The effect of various organic and inorganic amendments on the properties of desurfaced soils were evaluated in this experiment. The treatment T2 (soil test based NPK + poultry manure) recorded the highest plant height (50.42 cm), number of leaves (221.78) and number of branches (6.11) at 60 days after transplanting. The yield attributes such as total number of flowers (95.33), total number of fruits (31.33) and per cent fruit set (32.95 per cent) were found to be higher for the same. The highest yield was obtained for the treatment T2 (soil test based NPK + poultry manure). The soils were also analysed after the harvest of the crop. The bulk density of soil after harvest was the lowest in treatment T3 (soil test based NPK + vermicompost) and was on par with T4 (soil test based NPK + coirpith compost). The content of organic carbon, available nitrogen, phosphorus and potassium recorded higher values in treatment T2 (soil test based NPK + poultry manure) than the other treatments. The biological properties such as microbial biomass carbon (374.133 μg g-1 soil) and dehydrogenase activity (3.630 μg TPF g-1 day-1) were the highest in treatment T2 (soil test based NPK + poultry manure) and T4 (soil test based NPK + coirpith compost) respectively. The study revealed that top soil mining for brick production predominantly affected bulk density, soil temperature and water holding capacity of the soils. The content of organic carbon and available nutrients such as N, P and K were also reduced. The biological properties like dehydrogenase enzyme activity and microbial biomass xii carbon reduced to a greater extent. Water samples from mined areas were polluted by cations like sodium and calcium and anions like nitrate, phosphate, bicarbonate and chloride to limited extent. Poultry manure application as an integrated nutrient management technique, followed by vermicompost application were found to be beneficial for the management of such desurfaced soils.
Available nutrient status of some red soils (Alfisols) from different regions in Kerala
(Kerala Agricultural University, 1986) Betty Bastin; Venugopal, V K
study was made on the available nutrient status of sixty surface samples collected from red soil (Alfisols) series identified in different regions in Kerala. Among the major nutrients, Bray 1 extractable phosphorus recorded high values for all the soil series. Nitrogen was low to medium in Vellayani, Cheriniyoor and Beypore, while it was medium in Chirakkal, Bharanikkavu and Kunhimangalam series. Low to medium levels of available potassium was observed in Chirakkal, Bharanikkavu, Beypore and Cheriniyoor series while Kunhimangalam and Vellayani series showed low levelsof available potassium. All the soils showed high phosphorus fixing capacity. DTPA extractable iron and manganese were more than adequate in the surface soils of all the soils investigated. Zinc was deficient to adequate in Vellayani, Bharanikkavu and Kunhimangalam series and marginal to adequate in Cheriniyoor, Beypore and Chirakkal series. Copper was deficient to adequate in Vellayani, Cheriniyoor and Kunhimangalam series while, adequate levels were observed in Bharanikkavu, Beypore and Chirakkal series.
Carbon sequestration and soil health under different organic sources in wetland rice
(Department of Soil Science and Agricultural Chemistry, Vellanikkara, 2018) Rajalekshmi, K; Betty Bastin
Evalulation of soil and water quality in potta watershed of pazhayannur block in Thrissur district
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 2017) Raghunath, H N; Betty Bastin
An investigation entitled ‘Evaluation of soil and water quality in Potta watershed of Pazhayannur Block in Thrissur district” was undertaken in the department of Soil Science and Agricultural Chemistry, College of Horticulture, Kerala Agricultural University during the Year 2016-17. An intial survey was carried out in the different reaches of the watershed to identify the water resources, crops. Vegetation, manures, fertilizers and pesticides used. Based on the data generated, thirty Soil samples were samples were collected from each reach. Soil samples were collected only during the pre-monsoon season (April to May, 2016) and post-monsoon November to December, 2016) season. The soil samples were characterized for texture, bulk density, particle density, water holding capacity (WHC), pH, electrical conductivity (EC), organic carbon (OC), cation exchange capacity (CEC), available nutrients (N, P, K, Ca, Mg, S, Fe, Mn, Zn, and Cu) and heavy metals (Pb, Ni, Cr, and Cd) and heavy metals (Pb,Ni,Cr and Cd). Water samples were analyzed for chemical properties like pH, EC, TSS, cations, (Na+ , Ca2+ , K+, Mg2+) anions (CI-1, SO42-, CO32-, HCO3- and NO3- )heavy metals Cd, Pb, Cr, and Ni). The texture of soils in all the three reaches were found to be sandy loam. Soils from all the reaches were acidic and the pH varied from 3.47 to 6.80 with very low electrical conductivity(0.021 to 0.170 dS m-1). Cation exchange capacity of the soil samples varied between 4.15 to 8.97 c mol (p+) Kg-1. in the soil samples of upper reach was deficient in soil OC. Deficiency of available N in all reaches and that of P in upper and lower reaches was observed. The highest deficiency of K was noticed in the soil samples of upper reach. All the reaches were deficient in secondary nutrients (Ca and Mg). The available heavy metals in the soil was found to be below toxic level and their contents decreased in the order of Pb > Ni > Cr > Cd. Micronutrients (Fe, Mn, Zn and Cu) were found to be sufficient and their contents followed the order Mn > Fe>Cu > Zn Significant differences were observed between upper and middle reached in the content of soil available N, P and K. The association of soil properties showed that the soil organic carbon (SOC) was significantly and positively correlated with soil water holding capacity and available nitrogen in all the reaches, whereas it was negatively correlated with the bulk density of soil. During both pre and post – monsoon periods, PH of the water samples ranged between acidic to neutral values (5.62 to 7.47). electrical conductivity of water samples ranged from 0.14 to 0.54 dS m-1 . The content of cations, viz.,Ca and Mg were high in post-monsoon season while Na and K were high in pre-monsoon season. Analysis of anionic composition of water samples showed that the content of anions viz., bicarbonates, chlorides and nitrates were higher in post monsoon compared to pre-monsoon. The heavy metals like lead, chromium and cadmium were found to be below detectable level in all the water samples collected during both pre and post –monsoon seasons. Water samples registered significant differences in the contents of Ca, Mg, HCO3- between pre and post –monsoon seasons . The quality of water from all the reaches can be rated as good and suitable for irrigation. Further studies can be focused on the assessment of the impact of different soil conservation measures on the soil health. Soil test based fertilizer recommendations including various organic resources have to be adopted by the farmers.
Fate of carbofuran applied to the soil basin of black pepper
(Department of Soil science and Agricultural chemistry, College of Horticulture, Vellanikkara, 1996) Betty Bastin; Wahid, P A
An investigation on the fate of carbofuran applied to the soil basin of black pepper (Piper nigrum L.) was conducted during 1992-1995 at the College of Horticulture, Vellanikkara. Laterite soils collected from the predominant pepper growing tracts of Kannur and Wayanad of Kerala state were used for the study. A field study was also conducted at the KADP farm attached to the College of Horticulture, Vellanikkara. The sorption of carbofuran in laterite soils and its persistence, influence of organic matter on the bio-availability of carbofuran, mobility of the insecticide in soil under field conditions and the effect of carbofuran on the growth of black pepper were assessed. The main findings of the study are given below. The sorption of insecticide in soil was found to be explained by Freundlich adsorption equation. The rates of sorption of carbofuran was not influenced by the organic matter contents . . An initial lag period was observed prior to carbofuran degradation in soil under laboratory conditions. Only one metabolite (3-hydroxycarbofuran) was detected as the product of degradation. The total content of 14C derived radioactivity was high in plants grown in soils with lowest organic matter content and vice versa. Hence, bioavailability of the insecticide is less in soils with high organic matter contents. So a discriminatory application of carbofuran is required depending on organic matter content of the soil. Thus for effective control of the pest in a soil with high organic matter content more quantity or carbofuran has to he applied than a soil with low content of organic matter. The residues of 14C-carbofuran absorbed plants left after HCl extraction, retained significant amounts of radioactivity which could be recovered following combustion. This indicated that determination of extraction efficiency by spiking or fortification of the samples with known quantities of insecticides would lead to overestimation of the recovery. The main metabolite of the carbofuran in the leaves was 3-hydroxy- carbofuran. Autoradiography of the bush pepper plants which was allowed to absorb 14C-carbofuran for 6 h showed that carbofuran was absorbed and translocated to the leaves and berry. Both carbofuran and hydroxycarbofuran were leached to the lower layers of soil (0-60 cm) during SW and NE monsoons. The content of hydroxycarbofuran was less than carbofuran in soils. In the foliage and berries carbofuran and the metabolite, 3-hydroxy- carbofuran accumulated. The content of hydroxycarbofuran was greater than that of carbofuran. As the harvesting time was delayed the content of residues also decreased. The early harvesting and use of immature berries may lead to more concentration of pesticide in the produce. This will lead to chances of more residue build-up in the human system.
Long term effect of field management on soil quality in ultisol
(Department of soil science and agricultural chemistry, College of horticulture,Vellanikara, 2013) Nithya, A M; Betty Bastin
Soil quality is directly related to agricultural sustainability. Assessment of soil quality is essential for determining the sustainability of land management systems. It is generally accepted that intensive agricultural production leads to a decline in soil quality. For this reason, it is highly essential to monitor soil quality to avoid soil degradation and in doing so, preserve the production capabilities of the land and protect environment. The response of soils to management and input depends on soil quality. It is therefore important to identify the soil characteristics responsible for changes in soil quality, which may eventually be considered as soil quality indicators for assessing agricultural sustainability. The present investigation has been undertaken to study the “Long term effect of field management on soil quality in Ultisol”. It was conducted in the main campus of Kerala Agricultural University, Vellanikkara during December, 2012 to June, 2013. The objective of the study was to evaluate the soil quality under different long term field management conditions in an Ultisol (Vellanikkara series) based on physical, chemical and biological indicators. Here, an attempt has been made to evaluate the physical, chemical and biological properties of soil using available soil quality indicators. Five different fields were selected namely, natural forest, rubber plantation, cocoa garden, STCR experimental field and tapioca fields. Soil samples were collected from three depths namely 0-15 cm, 15-30 cm and 30-60 cm. The different sampling sites within each field were selected based on slope percentage. The samples were characterized for soil texture, aggregate size distribution, soil temperature, water holding capacity, single value constants, pH, EC CEC, AEC, SiO2/R2O3, organic carbon , lime requirement, available macronutrients, secondary nutrients, micronutrients, counts of bacteria, fungi and actinomycetes and enzyme activity. The sampling areas were also surveyed and documented for the presence of earthworms and termites. The physical characteristics like water holding capacity, soil aggregate stability and soil temperature showed a decreasing trend with depth in the different fields. Forest ecosystem showed the most conducive physical characteristics followed by cocoa and rubber. The contents of available nutrients, secondary nutrients and micronutrients were found to be the highest in surface samples. The forest ecosystem showed relatively high values for organic carbon, and available nutrients like nitrogen, sulphur, boron, iron, manganese, zinc and copper. Microbial activity was found to be the highest in surface soils in almost all fields. The highest counts of bacteria and actinomycetes were reported in forest ecosystem and lowest in tapioca field. Fungal activity was found to be the highest in cocoa field followed by forest ecosystem. Enzyme activity was also found to be the highest in surface soils in the different fields. Soil quality was evaluated using available soil quality indicators. Based on scoring with the soil quality parameters, the highest scoring was observed for natural forest followed by cocoa field. Correlations between various soil quality parameters of different fields were also worked out. .
Modeling soil carbon dynamics of two major ecosystems of humid tropics
(Academy of Climate Change Education and Research, Vellanikkara, 2015) Gopika Rani, K S; Betty Bastin
A study on “Modelling soil carbon dynamics of two major ecosystems of humid tropics” was carried out in the Academy of Climate Change Education and Research (ACCER) during 2014-2015. The study was done using two soil carbon models such as Roth-C and CENTURY. The objectives of the study included the evaluation of suitability of these two models in rice and teak ecosystems and also to analyse the soil organic carbon changes due to predicted climate change scenarios. The study was based on secondary data sets collected from experiments done in paddy fields and teak plantations of Pattambi and Thrissur areas respectively belonging to humid areas. The simulated total soil organic carbon (1965 to 2050) by Roth-C and CENTURY models was found to be declining in rice ecosystem. The active carbon in rice ecosystem showed decreasing trend and thereafter it was showing an increasing trend. In case of slow carbon it showed a gradual declining trend during the period from 1965 to 1990. There after it started to increase in a rapid manner during the next eleven years and afterwards it started decreasing. The passive carbon in rice ecosystem kept on increasing throughout the simulation period. In teak ecosystem, both the models Roth-C and CENTURY predicted a declining trend of total soil organic carbon. The active carbon of teak ecosystem decreased by the end of third year and slowly increased by ninth year. By the end of fifty five year it showed a rapid decline and slowly increased by the following years. Slow carbon pool showed a declining trend up to thirty years and kept on increasing to the next thirty years. Then it showed a rapid decline and thereafter it started to increase. The passive carbon kept on decreasing throughout the period. The model efficiency of Roth-C and CENTURY models for rice ecosystem were 0.63 and 0.82, respectively whereas for teak ecosystem the values were 0.69 and 0.88. Hence it was concluded that for simulation of soil organic carbon, both the models are suitable, but CENTURY model was more efficient than Roth- C model. From the study based on different RCP scenarios, RCP 8.5 had predicted higher temperature and precipitation values compared to others (RCP 6.0, RCP 4.5 and RCP 2.6) over both Pattambi and Vellanikkara. In rice ecosystem, it was noticed that in 2015 and 2050, RCP 2.6 recorded the highest values of total soil organic carbon and the lowest values were by RCP 8.5, respectively. In the case active carbon, RCP 4.5 recorded the highest values and RCP 8.5 recorded the lowest values. The highest value of slow carbon was recorded by RCP 2.6 and the lowest by RCP 8.5. The predicted values of passive carbon showed highest values by RCP 6.0 and recorded the lowest by RCP 4.5. In the study based on predicted climate change scenarios in teak ecosystem, RCP 4.5 recorded highest values of total soil organic carbon in 2015 and 2050 where as the lowest value was found by RCP 6.0 in 2015 and RCP 8.5 in 2050. The highest value of active carbon was found in 2015 by RCP 4.5 and in 2050 by RCP 2.6. The lowest values of active carbon were recorded by RCP 6.0 and RCP 8.5 in 2015 and 2050 respectively. In 2015 the highest value of slow carbon was recorded by RCP 4.5 and in 2050 by RCP 2.6. The least value of slow carbon was recorded in 2015 by RCP 6.0 and in 2050 by RCP 8.5. The passive carbon simulated by different RCPs, it was observed that RCP 4.5 predicted the highest value in 2015 and 2050. Then the lowest values recorded by RCP 6.0, respectively The present study indicated that modelling is suitable for studying carbon dynamics in soils under rice and teak ecosystems. It highlights the potential of CENTURY model over Roth-C model in terms of simulation of soil carbon. Using different scenarios it is possible to know that, what might be the future conditions of soil carbon and its different pools.
Nutrient management for sustainable rice production in the black soils of Kerala.
(Department of Soil Science and Agricultural Chemistry,College of Horticulture, Vellanikkara, 2011) Danish Tamuly; Betty Bastin
Physico-chemical characterisation of red soils in different regions of Kerala
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 1985) Betty Bastin; Venugopal, V K
In the present study an attempt has been made to evaluate the morphological, physical and chemical characteristics of red soils occurring in different regions of Kerala. Six soil series representing red soils identified by the soil survey unit of the department of Agriculture, Kerala state were selected for the investigation. The series identified were Vellayani, Cherniyoor, Bharanikkavu, Beypore, Chirakkal and Kunhimangalam located in Trivandrum, Quilon, Calicut and Cannanore districts. Profile pits were dug at these different locations and examined for their morphological features. Soil samples representing the different horizons were collected for laboratory studies. The physico-chemical characteristics of the soils and chemical composition of clays of the profile samples were investigated with a view to study the interrelationship between the various properties and to relate these characteristics to the genesis of these soils. Surface samples collected from different locations under each series were also analysed for available nutrients. The morphological features of the soil profiles revealed prominent red hues with increase in redness with depth. All the soil profiles were well drained, with ill defined horizons, exhibited good structural development and were devoid of coarse fragments. The soils were all sandy in nature, with the fine sand fraction predominating. Clay illuviation was observed in all the profiles. In respect of available water content appreciable variation was not observed between soil series. The highest available water content was recorded in Kunhimangalam series while beypore series had the lowest. All soils were acidic with very low electrical conductivity. The organic carbon, nitrogen and C/N ratios were low and showed little variation between soil series. Silica recorded very high values for all the soils while total Fe2 O3 and AI2 O3 did not reveal much variations between soil series. The total reserves of CaO, MgO, K2 O and P2 O5 were very low and is mainly a reflection of minerology of sand fraction which was dominated by quartz. In respect of total micronutrients iron and manganese recorded high values while Zinc and copper were low and did not reveal much variations between the different soils. Iron, Zinc and copper showed positive relationship with finer fraction while in the case of manganese, the relationship holds good in the case of fine sand fraction only. The e. c. e. c. values obtained were very low and less than the c. e. c. values determined by neutral N NH4 OAc method. Effective c. e. c. showed positive significant relationship with organic matter. The content of exchangeable bases were in the order Ca Mg Na K. Exchangeable hydrogen was more than exchangeable aluminium. Cherniyoor series recorded the highest percentage base saturation while the lowest value was obtained for Kunhimangalam series. The dithionite extractable iron was the predominant iron fraction in all the soils and based on the ‘degree of freeness of iron’ Kunhimangalam series was the oldest in respect of age followed by Chirakkal, Cherniyoor, Vellayani, Beypore and Bharanikkavu. The Ammonium oxalate extractable iron and iron oxide ratio, recorded very low values for all the soil series. The available nutrients of the surface samples showed high levels of phosphorus in all the soils. Nitrogen was low to medium in Vellayani, Cherniyoor and Beypore while it was medium in Bharanikkavu, Chirakkal and Kunhimangalam series. In the case of available potassium loe to medium levels were observed in Chirakkal, Bharanikkavu, Beypore and Cherniyoor series while Kunhimangalam and Vellayani series showed low levels of available potassium. The phosphorus fixing capacity for all the series was high. The DTPA extractable iron and manganese were more than adequate in the surface horizons of all the series. Zinc was deficient to adequate in Vellayani, Bharanikkavu and Kunhimangalam series and marginal to adequate in Cherniyoor, Beypore and Chirakkal series. Copper was deficient to adequate to Vellayani, Cherniyoor and Kunhimangalam series, while adequate levels were observed in Bharanikkavu, Beypore and Chirakkal series. Silica formed the predominant element of the clay fraction. The Si O2/AI2 O3, Si O2/Fe2 O3 and Si O2/R2 O3 ratios recorded for all the soils were higher than the values reported for typical laterite soils.
Physico-chemical properties of rain water harvested under different situations in lateritic
(Department of soil science and agricultural chemistry, College of horticulture,Vellanikara, 2014) Ibrahim Hassen Abdu; Betty Bastin
Soil Test based fertilizer requirements for oriental pickling melon (Cucumis melo var. conomon)
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 2009) Lamina, V K; Betty Bastin
The emphasis on soil test based fertilization has become much more relevant in the present scenario of high fertilizer cost and yield maximization programme. Oriental pickling melon (Cucumis melo var. conomon) belonging to the family Cucurbitaceae is an important vegetable crop of Kerala. The present study was undertaken to test verify the targeted yield equations developed for oriental pickling melon by the AICRP on STCR centre, Vellanikkara of Kerala Agricultural University in farmers’ field. For this purpose fields were selected at two locations in Pattikkad area of Thrissur district during the year 2008-09. Test experiments consisted of six treatments namely, farmer’s practice (T1), package of practices recommendations of KAU (T2), soil testing laboratory recommendations of Kerala (T3), STCR recommendations for a yield target of 30 t ha-1 (T4), STCR recommendations for a yield target of 45 t ha-1 (T5) and organics alone (T6) . Among the treatments, T4 (STCR recommendation for a yield target of 30 t ha-1) gave the maximum yield and B/C ratio. Soil, plant and fruit analyses were carried out to study the nutrient interactions in the plant and the quality aspects of the fruit. From the interaction study it was found that the maximum uptake occurs for the nutrient K followed by N and K. Fruit yield as such was influenced by the soil K content. Similarly the plant K content also showed positive correlation with the yield. High N contents in the soil at the harvest stage of the crop negatively influenced the yield. Fruit yield increased with the N content in the fruit. Keeping quality of the fruit decreased as the N content in the fruit increases. Crude fibre content decreased the rotting percentage of the fruit. Addition of fertilizers increased the vitamin C and Si contents in melon. From this study it can be concluded that the fertilizer applied as per the targeted yield equations is contribute much towards the crop requirements for good yield. However future works have to be done in several other locations before the recommendation of these equations.
Soil test crop response studies on groundnut in laterite soils of Kerala
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 2005) Sidha, P S; Betty Bastin
The investigation entitled “STCR studies on groundnut (Arachis hypogaea L.) in laterite soils of Kerala” was conducted during 2003-2004 in the farm attached to College of Horticulture, Vellanikkara. Objectives of the study were to develop soil test based balanced fertilizer recommendation for specific yield targets to groundnut in laterite soils of Kerala, and to develop a basis for fertilizer recommendation for maximum and economic pod yield at varying STVs. The experiment consisted of FGE and STCR experiment. The aim of FGE was to create desired gradient in soil fertility in one and the same field by applying graded doses of N, P and K fertilizers and raising an exhaustive crop, fodder maize Co-1. After development of fertility gradient, the STCR experiment was conducted in the same field with the test crop groundnut variety TAG-24. The soil nutrient status before and after the experiment were analysed for both FGE and STCR. The nutrient requirements of groundnut variety TAG-24 were estimated as 49.46, 4.25 and 19.52 kg ha-1 N, P and K respectively to produce one tonne of pod. The soil efficiencies were worked out as 28.11, 7.70, 6.88 per cent for N, P and K respectively for groundnut in laterite soil. The contribution of nutrients from fertilizers were estimated as 45.61, 11.18 and 27.33 per cent for N, P and K respectively and the contribution from organic manure were 49.46, 4.25 and 19.52 per cent N, P and K respectively to produce one tonne of pod. Fertilizer prescription equations for specific yield targets of groundnut variety TAG-24 were derived by using the above basic data and the equations were as follows: Without FYM FN = 108.44 T - 0.616 SN FP = 38.01 T - 1.577 SP FK = 71.43 T - 0.305 SK With FYM FN = 108.44 T - 0.616 SN - 1.59 OM FP = 38.01 T - 1.577 SP - 1.87 OP FK = 71.43 T - 0.305 SK - 1.85 OK Multiple regression models were calibrated with yield as dependent variable and soil available and applied nutrients as independent variables. Among the three nutrients, P and K showed normal type (+, -, -) of response in both models with 15 and 17 variables. So equations were calibrated for these two nutrients. The equations were as follows: With 15 variables FP = 32.47 - 0.709 SP FK = 321.36 - 0.429 SK With 17 variables FP = 76.27 - 2.645 SP FK = 312.37 - 0.413 SK Simple correlation coefficient was worked out for nutrient uptake with yield, nutrient uptake and yield with available and applied nutrients and major plant nutrient content with yield. The study is useful to adjust fertilizer doses based on the specific objective and available resources of groundnut farmers of the state.