Sharma, R.P.Suri, Deepika2024-08-272024-08-272023-02-10A-2018-40-027https://krishikosh.egranth.ac.in/handle/1/5810213745The present investigation was carried out in an on-going long-term fertilizer experiment, initiated during 1972 at experimental farm of Department of Soil Science, CSK HPKV Palampur, to study the effect of chemical fertilizers, organics and lime on fractions of micronutrient cations under continuous maize-wheat cropping in an acid Alfisol. The experiment was laid out in a randomized block design with twelve treatments. The soil of the experimental site was silty loam and classified taxonomically as “Typic Hapludalf”. Soil samples were collected after wheat (rabi, 2019-20 and 2020- 21) harvest from the surface (0-0.15 m) and sub-surface (0.15-0.30 m) layer. Soil samples were analyzed for various chemical, physical and microbiological properties using standard analytical procedures. Different fractions of Zn, Cu, Mn and Fe were determined in surface and sub-surface soil samples collected after wheat harvest (rabi, 2019-20) and soil samples drawn from adjacent buffer plots. The grain and stover/straw yield of maize and wheat was recorded. The nutrient concentration was determined in grain and stover/straw samples of maize & wheat and uptake was calculated. Continuous use of chemical fertilizers, organics and lime under maize-wheat system in an acid Alfisol brought out marked depletion in the pools of all the micronutrient cations as compared to buffer plots. The content of different fractions of Zn, Cu, Mn and Fe in sub-surface layer was less than that in surface layer. However, the treatment wise trend was almost similar to that under surface layer. Highest grain yield of maize (54.77 and 44.91 q ha-1 during 2019 and 2020, resectively) and wheat (28.11 and 24.67 q ha-1 during 2019-20 and 2020-21, respectively) was recorded under 100% NPK + FYM treatment which was at par with 100 % NPK + lime. FYM and lime treatments resulted in significantly higher uptake of all the nutrients by both the crops compared to other treatments. Most of the fractions of Zn, Cu, Mn and Fe correlated negatively and significantly with pH and positively and significantly with OC and CEC. Simple correlation and regression studies revealed that organically bound and exchangeable fractions were found to play major role in the nutrient supply, crop productivity and nutrients’ uptake.EnglishThesis