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A field experiment was conducted for two consecutive years 2020-2021 and 2021-2022 on clay loam soil at Agricultural College Farm, Bapatla to study the direct and residual effect of integrated use of organics and inorganics on soil nutrient status under rice-sorghum cropping system. The results revealed that at all the growth stages of rice, the highest available nitrogen, phosphorus and potassium were recorded with the application of 100% RDF + 25% N through GLM (T8) and this was on par with T9 (100% RDF + 12.5% N through FYM + 12.5% N through GLM), T3 (125% RDF through inorganic fertilizers) and T7 (100% RDF + 25% N through FYM, whereas the highest available sulphur was recorded in  100% RDF + 25% N through GLM (T8) and it was on par with T9 (100% RDF + 12.5% N through FYM + 12.5% N through GLM) and T7 (100% RDF + 25% N through FYM during 2020 and 2021.  In succeeding sorghum, significantly highest soil available N, P2O5, K2O and sulphur were recorded in T9 (100% RDF + 12.5% N through FYM + 12.5% N through GLM) and it was on par with T8 (100% RDF + 25% N through GLM) and T7 (100% RDF + 25% N through FYM) during both the years of study. Irrespective of the treatments applied to rice crop, the sub plot that received 100% RDF (S3) in rabi recorded significantly highest soil available nutrients at all stages of crop which was on par with 75% RDF (S2) except available sulphur whereas increased NPK levels from 75% RDF (S2) to 100% RDF(S3) did not show any significant difference and lowest was recorded in control (S1) during both the years of study, respectively.

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An investigation was carried out to study different forms of phosphorus under major cropping systems in Y.S.R. Kadapa district of Southern Zone of Andhra Pradesh. Five soil samples from each cropping system at 0-15 cm depth collected from each cropping system to study their physicochemical properties, status of available P2O5 and different forms of P. Majority of the soils were moderately alkaline in reaction, non-saline, free lime content indicating that these soils are moderately calcareous, medium to high in available P2O5. Highest mean values for available P2O5 (182.41 kg ha-1), Al-P (80.82 mg kg-1), Ca-P (118.55 mg kg-1) and total-P (434.35 mg kg-1) were recorded in groundnut monocropping system whereas for saloid P (23.01 mg kg-1), Fe-P (69.82 mg kg-1) and other forms of P (228.35 mg kg-1) highest mean values were recorded under sunflower-sesame, groundnut-groundnut and fallow-bengal gram cropping systems, respectively.