Targeted Yield Model Research Articles

Development of Integrated Fertilizer Prescription Based on STCR-IPNS for Brinjal through Inductive Cum Targeted Yield Model in Mannadipet Soil Series of Puducherry, India

Development of Integrated Fertilizer Prescription Based on STCR-IPNS for Brinjal through Inductive Cum Targeted Yield Model in Mannadipet Soil Series of Puducherry, India

Optimization of fertilizer doses for desired yield targets of hybrid brinjal under IPNS by targeted yield model

Optimization of fertilizer doses for desired yield targets of hybrid brinjal under IPNS by targeted yield model

Balanced Nutrient Recommendations for Dry Chilli in an Inceptisol of Tamil Nadu based on a Targeted Yield Model

Background: Considering the high cost of fertilizers and adverse effect of its overuse on environment and soil health, proper organic manure-fertilizer recommendations on the basis of soil test values, residual effect and yield targets of chilli becomes vital. Methods: Field experiment was carried out on Periyanaickenpalayam soil series of Inceptisol soil order at farmers holding, Dindigul, Tamil Nadu during 2021-2022 after establishment of marked fertility gradient with respect to soil available N, P and K by gradient experiment with fodder sorghum. The test crop experiment with chilli was laid out in a fractional factorial design comprising of 24 treatments with 4 levels of N (0, 50, 100 and 150 kg ha-1), 4 levels for both phosphorus pentoxide (P2O5) and potassium dioxide (K2O). Farmyard manure (FYM) levels were 0, 6.25 and 12.5 kg ha-1.From the field experiment data, the fundamental parameters- nutrient requirement (NR) and nutrients contributions from soil (Cs), fertiliser (Cf) and farmyard manure (Co)-were determined. Result: The percentage of nutrients estimated from fertiliser (%Cf) that contributed towards the total amount of nutrients taken up by dry chilli was calculated to be 44.09, 39.29 and 76.91 per cent of N, P2O5 and K2O, respectively. K2O greater than N greater than P2O5 was seen as the order of the fertiliser nutrient per cent contributions to total nutrient uptake. Incase of nutrient contribution form soil (% Cs) the order is P2O5 greater than N greater than K2O. FYM contributed (% Co) 29.42, 14.40 and 38.73 per cent of N, P2O5 and K2O. One quintal of dry chilli production was estimated to require (NR) 4.24 kg of nitrogen, 1.91 kg of phosphorus pentoxide (P2O5) and 4.80 kg of potassium oxide (K2O) as nutrients. Fertiliser prescription equations (FPEs) for dry chilli and ready reckoners for the operating range of soil test values for the intended yield target experiment under NPK alone and IPNS were built using basic data.

Sustaining Soil Fertility and Yield by Inductive cum Targeted Yield Model-based Fertilizer Prescriptions for Finger millet (Eleusine coracana L.) in Alfisols of Tamil Nadu, Southern India

Background: Finger millet cultivation in Alfisols (Typic rhodustalf, Palaviduthi soil series) demands an optimal integrated plant nutrient supply to achieve desired yields. In order to develop the soil test crop response to fertilizer and farm yard manure (FYM) through integrated plant nutrition system (STCR-IPNS) in terms of nutrient uptake, yield and pre-sowing STVs, a field investigation on Finger millet [Eleusine coracana (L.) Gaertn.] was conducted at the farmer’s field of Thoppupatti village, Dindigul district, Southern Agro-climatic zone of Tamil Nadu, Southern India during December 2021-August 2022. Methods: By adopting the Inductive cum Targeted Yield Model before the test crop of Finger millet, a artificial soil fertility gradient was created by the application of graded levels of NPK fertilizers with fodder sorghum as a gradient crop. Result: The basic data viz., N, P and K nutrients for producing 1 tonne of finger millet grain were 48 kg, 23 kg and 44 kg; the soil contributed 14.86%, 19.18% and 18.95%; fertilizer contributed 44.16%, 32.79% and 59.75% for N, P and K and farmyard manure (FYM) contributed 28.47%, 11.77% and 33.78%, respectively. Fertilizer prescription equations for finger millet and ready reckoners for the operational range of soil test results for the intended yield target under NPK alone and IPNS (NPK + FYM) were produced using the basic data.

Response of Hybrid Castor Under Different Fertility Gradient: Correlation Between Castor Yield and Normalized Difference Vegetation Index (NDVI) Under Inductive Cum Targeted Yield Model on an Alfisol

ABSTRACT Precision application of nutrient based on soil test value is important for improving nutrient use efficiency and yield of hybrid castor. Field trial was conducted during 2021 at Tapioca and Castor Research Station, Yethapur, Salem District, Tamil Nadu, India (11035’ N, 780 29’ E). Fertilizer prescription equations (FPEs) were developed for hybrid castor by adopting inductive cum targeted yield model approach under irrigated condition on Alfisol. Initially, soil fertility gradients were established with respect to soil available N, P and K nutrients, and 24 treatments were imposed in three fertility strips under factorial randomized design. Principle component analysis revealed that all the variables accounted for developing the FPEs of hybrid castor are present at the positive quadrant which mean that all the variables are highly important toward the castor seed yield production. From the field experimental data, the basic parameters [nutrient requirement (NR) and nutrients contributions from farmyard manure (Co), fertilizer (Cf), and soil (Cs)] were computed. The nutrient required for producing one quintal of hybrid castor seed yield was evaluated as 3.20 kg of nitrogen, 1.23 kg of phosphorus pentoxide (P2O5), and 3.28 kg of potassium oxide (K2O). The study revealed that soil nutrient contribution was high in case of available phosphorus (41.87%), available nitrogen (21.56%), and available potassium (19.12%), respectively, toward P, N, and K nutrient uptake by hybrid castor. The nutrient contribution from farmyard manure (Co) toward the total uptake was 21.40% of N, 10.35% of P2O5, and 26.06% of K2O, respectively. FPEs for hybrid castor and a ready reckoner of fertilizer dosages were developed using basic data for operational range of soil test values for intended yield target under inorganic fertilization alone and Integrated plant Nutrient System (IPNS) (NPK and FYM).

Effect of Soil Test Crop Response (STCR) and STCR –Integrated Plant Nutrition System (IPNS) Based Fertilizer Prescription Equations on Maize Productivity, Economics and Soil Fertility Status in Vertisols of Northern Karnataka

A study on Soil Test Crop Response based Integrated Plant Nutrition System (STCR - IPNS) was conducted adopting an Inductive cum Targeted yield model in vertisols of Northern Karnataka at Main Agricultural Research Station (MARS), UAS, Dharwad, Karnataka during kharif 2020-21 in order to develop STCR and STCR-IPNS fertilizer prescription equations (FPEs) for achieving desired yield targets of maize. Fertilizer doses at varying soil test values, for attaining 60, 80 and 100 q ha-1 target grain yield of maize have been worked out based on the initial soil test values of available N, P and K and the quantities of N, P and K added through farm yard manure (FYM). Using these equations, validation trials were conducted during kharif 2021-22 at MARS, Dharwad and Irrigation Water Management Research Centre (IWMRC), Belavatgi. The results of the experiment indicated that at both the locations, the per cent achievement of the targeted yield was within ± 10 % variation proving the validity of the equations for prescribing integrated fertilizer doses for maize. The highest grain yield was recorded in STCR-IPNS equation with 100 q ha-1 target yield (Dharwad -104.8 q ha-1, Belavatgi – 102.3 q ha-1) recording an increase of 67 and 69 per cent over recommended package of practices at Dharwad and Belavatgi, respectively. However, it was found to be on par with Jabalpur STCR equation with 100 q ha-1 target yield and STCR-NPK alone equation with 100 q ha-1 target yield. Higher gross returns were recorded under STCR-IPNS equation with 100 q ha-1 target yield owing to higher grain and stover yields. While STCR equation developed at Jabalpur with 100 q ha-1 target yield recorded higher net returns. The post-harvest soil available NPK indicated better build-up and maintenance of soil fertility by the soil test based fertilizer recommendation under IPNS. Targeting 100 q ha-1 grain yield for maize under STCR approach was found to be ideal in terms of yield, economics and soil fertility maintenance in vertisols of Karnataka. The fertilizer prescription equations developed for maize under IPNS can be recommended for vertisols of Northern Karnataka for achieving target yield of 100 q ha-1 with sustained soil fertility and it can be extrapolated to other agro-climatic zones of Karnataka on similar and allied soil types.

Soil test crop response based integrated plant nutrition system for hybrid castor on an Alfisol

Background: In the era of precision agriculture, application of fertilizer based on soil testing is an essential tool to prescribe nutrient doses for crops to improve nutrient use efficiency and yield of hybrid castor. Methods: Field experiment was conducted in 2021 at the Tapioca and Castor Research station, Yethapur, region near Salem city, Tamil Nadu, India (11035’N, 78029’E). By adopting inductive cum targeted yield model fertilizer prescription equation (FPEs) were developed for hybrid castor under irrigated condition for Alfisol soil order. Initially soil fertility gradient were established with respect to soil available N, P and K nutrients and twenty four treatment were imposed in three fertility strips under factorial randomized design. The basic parameters [nutrient requirement (NR) and nutrients contributions from soil (Cs), fertilizer (Cf) and farmyard manure (Co)] were calculated from the field experimental data. Result: The nutrient required for producing one quintal of hybrid castor seed yield was evaluated as 3.20 kg of nitrogen, 1.23 kg of phosphorus pentoxide (P2O5) and 3.28 kg of potassium oxide (K2O). The study revealed that soil nutrient contribution was high in case of available phosphorus (41.87%), available nitrogen (21.56%) and available potassium (19.12%) respectively toward P, N and K nutrient uptake by hybrid castor. The nutrient contribution from farmyard manure (Co) towards the total uptake was 21.40% of N, 10.35% of P2O5 and 26.06% of K2O respectively. Using basic data, FPEs were developed for hybrid castor and ready reckoner were developed for operational range of soil test values for desired yield target under NPK alone and IPNS (NPK and FYM).

Influence of integrated nutrient application based on STCR approach on nutrient uptake of rice under ricemaize cropping sequence

Soil testing helps the farmers to use fertilizers according to need of crops. Fertilizer use for targeted yield is an approach which take into account the crop need and nutrient present in the soil. A study on soil test crop response based integrated plant nutrient ion system (STCR) were conducted adopting targeted yield method in non-calcareous sandy loam soil of Ustifluvents at Mandan Bharti Agriculture College, Agwanpur, Saharsa during the two consecutive of 2018 and 2019. The experiment was laid out in RBD with nine treatments replicated thrice. The STCR approach with or without FYM at low, medium and high target yield markedly increase the yield and uptake of NPK of rice. Thus, the targeted yield model used to develop fertilizer precipitation equations provides a strong basis of soil fertility maintenance consistent with high productivity and efficient nutrient management for sustainable and enduring agriculture. This also improved the relationship between farmers and scientists and built confidence between them.

Soil Test based Targeted yield equations for blackgram (Vigna mungo L.) through Integrated Plant Nutrition System on Alfisol

Using Ramamoorthy's inductive methodology for assessing the soil test based crop requirement by adopting an Integrated Plant Nutrition System to create Fertilizer Prescription Equations (FPEs) for blackgram with the prime objective of attaining the targeted yield by the farmers. A field experiment was conducted out on red non-calcareous sandy loam soil belonging to the Palaviduthi soil series (Typic Rhodustalf) during rabi 2021-22. The experiment comprised of eleven treatments viz., STCR - NPK alone and STCR - IPNS for yield targets 1.0,1.2,and 1.4 t ha-1, Blanket (25:50:25) @ 100% with and without FYM (12.5 t ha-1), FYM alone @ 6.25 and 12.5 t ha-1 and absolute control in randomized block design with three replications. From the experimental data, basic parameters viz., nutrient requirement (NR), per cent contribution from soil (Cs), per cent contribution from fertilizers (Cf), and per cent contribution from FYM (Cfym) were computed. The quantity of fertilizers contributed by the application of Farmyard manure was assessed. It has been found that the nutrient requirement for producing one quintal grain of blackgram was 4.77 kg of N, 4.50 kg of P2O5, and 5.05 kg of K2O. The per cent contribution from soil (Cs) was 15.61, 29.91, and 8.12 for N, P, and K respectively and the percent contribution from fertilizers (Cf) and FYM (Cfym) was 48.61 and 37.19 for N, 44.78, and 14.63 for P2O5 and 55.72 and 31.71 for K2O. FPEs for blackgram were generated using these basic parameters through a Soil Test Crop Response based Integrated Plant Nutrition System (STCR-IPNS). Fertilizer Prescription Equations (FPEs) created in this mode were used to create nomograms for a range of soil test values and yield targets. Thus the Inductive cum Targeted Yield Model used to develop fertilizer prescription equations provides a strong basis for soil nutrient maintenance consistent with high productivity and efficient nutrient management in farming for sustainable and enduring agriculture.

Inductive cum targeted yield model based Integrated fertilizer prescriptions for tomato (Solanum lycopersicum L.) under drip fertigation on an alfisol

Soil test crop response (STCR) correlation studies under Integrated Plant Nutrition System were conducted in the western agro-climatic zone of Tamil Nadu during 2020-2021 to devise the fertilizer prescription equations for tomato (Solanum lycopersicum L.) under drip fertigation on an alfisol. The equations were derived by following Ramamoorthy’s Inductive cum targeted yield model. The nutrient requirement of N, P2O5 and K2O for producing one quintal of tomato fruit was found to be 0.22, 0.11, 0.27 kg respectively. The per cent contribution of nutrients were 37.93, 46.73 and 29.53 of N, P2O5 and K2O from soil (Cs) and 47.84, 31.12 and 74.13 of N, P2O5 and K2O from fertilizers (Cf) respectively. Two organic sources were applied viz., FYM (Farm Yard Manure) and Biocompost and the per cent contribution of nutrients from FYM were 38.36, 13.22 and 52.17 of N, P2O5 and K2O and from biocompost were 43.34, 10.90 and 57.00 of N, P2O5 and K2O respectively. Fertilizer adjustment equations were formulated for STCR-NPK alone, STCR-IPNS (FYM) and STCR-IPNS (Biocompost) by applying the basic parameters such as NR, Cs, Cf, Cfym, Cbiocompost. A ready reckoner of fertilizer doses for a set of soil test values at yield targets 80 and 90 t ha-1 was computed. The findings also showed that the adoption of STCR-IPNS could save more fertilizers.

Impact of Long-term Application of Organic and Inorganic Nutrient Through Inductive cum Targeted Yield Model on Soil Physical Properties under Pearl Millet [Pennisetum glaucum (L.)] –Wheat [Triticum aestivum (L.)] Cropping System of Semi-arid North-West India

ABSTRACT Sustainability of cereal-based cropping system is important for the livelihood and food security in semi-arid regions. The present study explores the impact of long-term organic and inorganic nutrients and integrated fertilization practices of soil test crop response (STCR) approach of inductive-cum-targeted yield model on soil physical properties and its correlation with soil organic carbon (OC) under pearl millet–wheat in sandy-loam soils of semiarid north-west regions of India. Results showed that OC in the soils significantly increased in farm yard manure (FYM) and integrated treatments up to a maximum of 135% and 148%, respectively, in a period of 8 years over the control in surface soils (0–15 cm). The increase in OC significantly increased the infiltration rate (IR), hydraulic conductivity (HC), soil water retention at all suctions, water stable aggregates (WSA) (> 0.25 mm) and mean weight diameter of the soil aggregates, while decreased the bulk density (BD) and penetration resistance (PR) both at surface and subsurface soil layers. Soil OC also showed a negative correlation with BD (r = −0.955) and PR (r = −0.820). The hydraulic properties of the soil, viz., soil water retention, showed a high positive correlation with field capacity (r = 0.973), 0.922 for permanent wilting point (r = 0.922), HC (r = 0.938), IR (r = 0.973), and WSA (r = 0.979) with OC. Thus, long-term application of organic material in conjunction with NP improved soil physical health, provided better environment to grow crops through improved nutrient concentration and its translocation that ultimately helps to achieve yield target through STCR (Soil Test Crop Response) approach of inductive-cum-targeted yield model.

Soil Test Based Fertilizer Prescriptions through Inductive cum Targeted Yield Model for Sesamum on Alfisol

Soil Test Based Fertilizer Prescriptions through Inductive cum Targeted Yield Model for Sesamum on Alfisol

Validation of Inductive cum Targeted Yield Model based FertiliserPrescription Equations for Pearl millet (var. CO 10) onInceptisol

The present investigation was undertaken to validate the Inductive cumTargeted yield model based Fertiliser Prescription Equations (FPEs)developed under Soil Test Crop Response based Integrated Plant NutritionSystem (STCR-IPNS) for desired yield target of pearl millet (var CO 10) ona mixed black calcareous soil (Periyanaickenpalayam soil series - VerticUstropept). The field experiment was conducted during Kharif 2019 at TNAUFarm, Coimbatore, and was laid out in a randomized block design with tentreatments that were replicated thrice. The results emanated from the fieldexperiment brought forth the fact that the various growth and yield attributesof pearl millet were significantly influenced by STCR treatments as comparedto blanket treatments. There was a +10% variation in achievement of yieldtargets proving the validity of the fertiliser prescription equations developedfor desired yield target of pearl millet (var CO 10) on a mixed black calcareoussoil. Using the data on grain yield and quantity of nutrients applied, thevarious parameters viz., per cent achievement, response ratio and benefit:cost ratio were computed. Among the treatments, STCR-IPNS-3.5 t ha-1has demonstrated its supremacy by registering higher grain yield of 3455kg ha-1 with a relatively higher response ratio of 12.57 kg kg-1 and BCR of1.94. STCR - IPNS-3.5 t ha-1 has recorded a yield increase of 43.1, 21.2 and74.6 per cent over blanket (100% RDF), blanket plus FYM 12.5 t ha-1,andfarmer’s practice respectively and the increase in response ratio was 4.28,1.18 and 5.27 kg kg-1 respectively. Therefore, for achieving higher grainyield, nutrient uptake, response ratio, and BCR in pearl millet (var CO 10)on a mixed black calcareous soil (Periyanaickenpalayam soil series - VerticUstropept), STCR-IPNS based fertiliser prescriptions can be followed.

Integrated fertilizer prescriptions through targeted yield model and prediction of post-harvest soil test values for Kharif Rice (Oryza sativa)

Integrated fertilizer prescriptions through targeted yield model and prediction of post-harvest soil test values for Kharif Rice (Oryza sativa)

Balanced Prescription for Big Onion through Inductive Cum Targeted Yield Model on an Alfisol

Balanced Prescription for Big Onion through Inductive Cum Targeted Yield Model on an Alfisol

"Refinement of Soil Test Crop Response - Integrated Plant Nutrition System based Fertilizer Prescriptions for Pearl Millet Variety on an Inceptisol"

A field experiment was conducted during rabi season of 2017-2018 on a mixed black calcareous soil (Typic Ustropept - Periyanackenpalayam soil series) at Eastern Block, Tamil Nadu Agricultural University, Coimbatore to refine the existing fertilizer prescription equations under Integrated Plant Nutrition System (IPNS) for hybrids to suit pearl millet variety. The experiment comprised of eleven treatments with three replications in Randomized Block Design. The experimental results revealed that there was a progressive increase in response from lower target to higher targets and the magnitude of response was higher under STCR-IPNS than under STCR-NPK alone treatments. Using the experimental data, the basic parameters viz., nutrient requirement (NR), per cent contribution of nutrients from soil (Cs), fertilizers (Cf) and FYM (Cfym) towards total N,P and K uptake by pearl millet (var. CO 10) were computed based on targeted yield model. It was found that pearl millet variety requires 2.81, 1.33 and 2.53 kg of N, P2 O5 and K2 O, respectively to produce one quintal of grain. The contribution of nutrients from soil, fertilizers and FYM for N was 26.36, 45.44 and 27.55 per cent; for P2 O5 it was 38.51, 44.14 and 16.04 per cent and for K2 O it was 10.33, 87.45 and 40.15 per cent respectively. Making use of the refined basic parameters, Fertilizer Prescription Equations (FPEs) were developed under NPK alone and IPNS for pearl millet variety. Ready reckoner of fertilizer doses (nomograms) were formulated for a range of soil test values and for desired yield target viz., 3.0, 3.5 and 4.0 t ha-1. For an average soil test value of 180:24:460 kg ha-1 and yield target of 4.0 t ha-1, 105, 51 and 25 kg of fertilizer N, P2 O5 and K2 O is to be appiled along with FYM @ 12.5 t ha-1. The extent of saving of inorganic fertilizers for pearl millet with the application of FYM @ 12.5 t ha-1 (with 21 % moisture, 0.64, 0.27 and 0.46 % N, P and K respectively) was 38, 22 and 25 kg of fertilizer N, P2 O5 and K2 O respectively.

Soil test crop response based Integrated plant nutrition system for desired yield target of preseasonal sugarcane ratoon on Inceptisols

Studies on Soil Test Crop Response based Integrated Plant Nutrition System (STCR - IPNS) were conducted adopting the Inductive cum Targeted yield model onInceptisols (VerticHaplustepts) in Rahuri, District Ahemadnagar, Maharashtra, India in order to develop fertilizer prescriptions through IPNS for the desired yield targets of preseasonal sugarcane ratoon. The field experiments were carried out with maize as gradient crop for plant cane and after harvest of plant cane, pre-seasonal sugarcane ratoon as test crop. Using the data on yield, initial soil test values on available nitrogen (N), phosphorus (P), potassium (K), doses of fertilizers and farmyard manure (FYM) applied and NPK uptake, the basic parameters viz., nutrient requirement, contribution from soil, fertilizers and FYM were computed. It was found that 1.56 kg N, 0.58 kg P and 1.04 kg K were required for producing one tonnemillable cane of preseasonal ratoon sugarcane. The per cent contributions of N, P and K from soil and FYM for preseasonal sugarcane ratoon were 37.65, 85.88 and 19.82 per cent and 11.83, 10.88 and 12.24 per cent, respectively. Making use of these basic parameters, fertilizer prescription equations were developed for pre-seasonal sugarcane ratoon (var. C0-94012) and an estimate of fertilizer doses formulated for a range of soil test values and desired yield targets under NPK alone and IPNS (NPK plus FYM).

Refinement of fertilizer recommendation based on Soil Test Crop Response technology for rice under System of Rice Intensification

A study on Soil Test Crop Response based Integrated Plant Nutrition System (STCR - IPNS) were conducted adopting an Inductive cum Targeted yield model in non-calcareous sandy loam soils of Lithic Haplusteptat Regional Research Station, Tamil Nadu Agricultural University, Paiyur, Tamil Nadu during Kharif 2013 in orderto develop fertilizer prescriptions equation (FPEs) through IPNS for the desired yield targets of rice under SRI technique. A ready reckoner of fertilizer doses at varying soil test value, for attaining 6 to 9 t ha-1 target grain yield of rice has been worked out. Using these equations a validation trial was conducted on Kharif 2014 at this station. The grain yield of rice ranged from 2.54 t ha-1 in absolute control to 8.65 t ha-1 in STCR-IPNS-9 t ha-1. The STCR-IPNS @ 8 t ha-1 was effective and economical as compare with any other treatments. The deviation recorded in the achievement of targets aimed was within the range of ± 10 per cent (90 – 110 %) proving the validity of the FPEs. The STCR treatments recorded relatively higher response ratio (RR) and benefit-cost ratio (BCR) over blanket and farmer's practice and STCR-IPNS treatments recorded relatively higher RR and BCR over STCR-NPK alone treatments. Post-harvest soil tests for NPK revealed that there was maintenance of soil fertility. The STCR-IPNS @ 8 t ha-1 was effective and economical as compare with any other treatments. Thus, the Inductive cum Targeted yield model used to develop fertilizer prescription equations provides a strong basis for soil fertility maintenance consistent with high productivity and efficient nutrient management for sustainable and enduring Agriculture.

Integrated Fertilizer Prescriptions for Transgenic Cotton Hybrids under Rainfed Situation through Inductive cum Targeted Yield Model on Vertisol

ABSTRACTThe fertilizer prescription equations were developed for rainfed Bt cotton on Pielamedu series (Typic haplusterts) by adopting the inductive cum targeted yield model, and fertilizer requirements were quantified for Bt cotton based on soil test and yield target. The validity of fertilizer prescription equations was done by conducting test verification trials at four locations in Perambalur district of Tamil Nadu developed for rainfed Bt cotton. The fertilizer prescription equations were used to calculate the fertilizer doses for STCR treatments. The percent achievement of the targeted yield was within ±10% variation in all the locations for both the yield targets under nitrogen, phosphorus, and potassium (NPK) alone and IPNS, proving the validity of the equations. STCR-IPNS based fertilizer recommendations for a yield target of 32 q/ha has recorded the highest yield, nutrient response ratio, and percent yield achievement in all the locations.

Validation of Soil Test and Yield Target Based Balanced Fertilizer Prescription Model for Rainfed Maize on Inceptisol

Soil Test Crop Response based fertilizer prescription equations for desired yield target of rainfed maize were developed under Integrated Plant Nutrition System (STCR-IPNS) on Irugur soil series (Typic Ustropept) of Tamil Nadu. On farm testing of fertilizer prescription equations are essential to demonstrate the effectiveness of technology delivery to the stake holders in need. The present study was undertaken to evaluate the targeted yield model through field experiments at six locations in Dindigul district, Western Zone of Tamil Nadu. The treatments included control, blanket recommendation, soil test crop response (STCR) based fertilizer dose for the yield targets of 4.0 to 6.0 t ha-1 , STCR-IPNS based fertilizer dose for the yield targets of 4.0 to 6.0 t ha-1 and farmer’s practice. In all the six locations, the per cent achievement of the targeted yield was within  10 per cent variation proving the validity of the equations for prescribing integrated fertilizer doses for rainfed maize. The highest mean grain yield was recorded in STCR-IPNS – 6.0 t ha-1 (5013 kg ha-1 ) recording an increase of 52.2 per cent over blanket recommendation. The highest per cent achievement, response ratio and B:C ratio of 97.2,17.47 and 2.28, respectively were recorded in the yield target of 5.0 t ha-1 under STCR-IPNS. The post-harvest soil available NPK indicated the build up and maintenance of soil fertility due to soil test based fertilizer recommendation under IPNS. The fertilizer prescription equations developed for rainfed maize under IPNS can be recommended for red non calcareous soils of Tamil Nadu for achieving the yield target of 5.0 t ha-1 with sustained soil fertility and it can be extrapolated to other agro-climatic zones of Tamil Nadu on similar and allied soil types.