Loading...
Thesis
Browse
7 results
Search Results
ThesisItem Open Access NITROGEN, POTASSIUM AND SULPHUR REQUIREMENT FOR TARGETED YIELD OF KHARIF SESAME(2010-04) VAGHANI JITENDRA JERAMBHAI; Polara K. B.A field experiment was conducted on medium black calcareous soil at Agricultural Research Station, Junagadh Agricultural University, Amreli and a cluster of field experiments were conducted on farmers‟ fields with medium black calcareous soils of different villages of Amreli district to study the “Nitrogen, potassium and sulphur requirement for targeted yield of kharif sesame” during kharif 2007 and 2008, respectively. The objective was to assess the effect of nitrogen, potassium and sulphur levels on growth, yield and yield attributes, quality parameters, content and uptake of nutrients and soil nutrients (N, P, K, S, Fe, Mn, Zn, Cu) availability as well as to develop targeted yield equations and to verify different yield targets. Twenty seven fertilizer treatments with three levels of nitrogen (0, 50 and 100 kg ha-1), three levels of potassium (0, 40 and 80 kg ha-1) and three levels of sulphur (0, 20 and 40 kg ha-1) were taken for investigation. The results of the field experiments revealed that the maximum dry matter yield was observed during the period of 60 DAS to harvest (49.96 %) followed by 30-60 DAS (32.02 %) and 0-30 DAS (18.02 %). The major (N, P, K, S) and micro (Fe, Mn, Zn, Cu) nutrient content in the plant decreased with advancement of crop growth. The accumulation of major (N, P, K, S) and micro (Fe, Mn, Zn, Cu) nutrients by crop was increased with advancement of its growth and age. The seed (1089 kg ha-1) and stover (2020 kg ha-1) yield, yield attributes like the plant height (106.0 cm), number of branches per plant (4.0), number of capsules per plant (80.0), number of seeds per capsule (59.0), the dry matter yield and CGR value, quality parameters like test weight (3.04 g), protein content (20.47 %) and oil yield (544.9 kg ha-1) were observed maximum under application of nitrogen @ 100 kg ha-1. The content of all the macro and micro nutrients in plant and seed did not influence by varying levels of nitrogen application, except nitrogen content. The uptake of all the macro (N, P, K, S) and micro (Fe, Mn, Zn, Cu) nutrients by stover at 30 DAS, 60 DAS and at harvest as well as their uptake by seed and total uptake by crop was recorded maximum with application of nitrogen @ 100 kg ha-1. Increasing levels of nitrogen did not affect the availability of macro and micro nutrients in soil, except available nitrogen, which was recorded highest at 100 kg N ha-1. The seed (1034 kg ha-1) and stover (1900 kg ha-1) yield of sesame found higher at 80 kg K2O ha-1. Similarly, plant height (99.0 cm), number of branches per plant (4.00), number of capsules per plant (72.0), number of seeds per capsule (56.9), test weight (2.91 g) and oil yield (516.0 kg ha-1) as well as the dry matter yield and CGR of crop at all growth stages were recorded significantly higher under application of 80 kg K2O ha-1. The content of nitrogen, phosphorus, sulphur and all the micro nutrients (Fe, Mn, Zn, Cu) in stover did not influence significantly under application of potassium at all growth stages and also in seed. While, the concentration of potassium was observed higher in stover at all the growth stages and also in seed under application of potassium @ 80 kg ha-1. The nitrogen and potassium uptake by stover at all growth stages as well as their uptake by seed and total uptake by crop, phosphorus uptake at 60 DAS, at harvest as well as its uptake by seed and total uptake by crop, S uptake at harvest and its uptake by seed and total uptake by crop were obtained maximum with application of 80 kg K2O ha-1. The uptake of micro nutrients (Fe, Mn, Zn, Cu) by stover at different growth stages as well as its uptake by seed and total uptake by crop was recorded higher under application of potassium @ 80 kg ha-1, except Mn uptake by stover at 30 DAS, which was observed maximum with 40 kg K2O ha-1. Only the availability of potassium in soil was increased with increasing level of potassium, while other macro and micro nutrients remain unaffected. The seed (1021 kg ha-1) and stover (1867 kg ha-1) yield of sesame were recorded highest with application of 40 kg S ha-1. Similarly, yield attributes like the plant height (99.0 cm), number of branches per plant (4.00), number of capsules per plant (71.0), number of seeds per capsule (56.0), quality parameters like test weight (2.86 g), oil content (50.30 %) and oil yield (513.8 kg ha-1) and dry weight of crop and CGR value also were observed higher under application of sulphur @ 40 kg ha-1. The content of all the macro and micro nutrients in plant and seed did not influence by varying levels of sulphur application, except sulphur content which was found higher in stover at all growth stages and also in seed with 40 kg S ha-1. The uptake of nitrogen and sulphur and the micro (Mn, Zn, Cu) nutrients by stover at 30 DAS, 60 DAS and at harvest as well as its uptake by seed and total uptake by crop, phosphorus uptake by stover at 30, 60 DAS and at harvest, potassium by 30 DAS, seed uptake, iron by 30, 60 DAS, at harvest, total uptake by crop was recorded maximum with application of sulphur @ 40 kg ha-1. Increasing levels of sulphur did not affect the availability of macro and micro nutrients in soil, except sulphur availability, which was significantly highest at 30 DAS, 60 DAS and at harvest of crop, under higher dose of sulphur i.e. 40 kg ha-1. The seed and stover yield of sesame, oil yield, total dry matter yield at 60 DAS and at harvest, uptake of nitrogen by stover at 60 DAS, potassium by stover at 30 and 60 DAS, phosphorus and manganese at 60 DAS, total uptake and sulphur and copper at 30, 60 DAS, at harvest and total uptake, iron by stover at 60 DAS, at harvest and total uptake, zinc by 60 DAS, at harvest, seed and its total uptake by crop were recorded significantly higher under application of nitrogen @ 100 kg ha-1 and potassium @ 80 kg ha-1. The stover yield of sesame, total dry matter yield at harvest, oil yield and sulphur uptake by stover at harvest, seed and its total uptake by crop, iron, zinc and copper by stover at harvest and total uptake, manganese by stover at 30 DAS, seed and total uptake by crop were recorded significantly higher under application of nitrogen @ 100 kg ha-1 and sulphur @ 40 kg ha-1. While, the uptake of potassium by stover at 30 and 60 DAS recorded higher at combined application of nitrogen @ 50 kg ha-1 and sulphur @ 20 kg ha-1. The growth, yield and yield attributes, quality parameters, content and uptake as well as availability of macro (N, P, K, S) and micro (Fe, Mn, Zn, Cu) nutrients did not influence significantly under combined application of potassium and sulphur. The requirement of nitrogen, potassium and sulphur for producing one quintal sesame seed was 4.85, 2.00 and 0.58 kg, respectively. Sesame seed yield were achieved within ± 1.33 to 8.50 per cent variation at different yield targets (6, 8, 10 and 12 q ha-1) from verified trials on the basis of derived equation of N (FN = 22.30 x T – 0.74 SN), K (FK2O = 18.76 x T – 0.56 SK) and S (FS = 9.06 x T – 2.24 SS). The additional seed yield was obtained at 8, 10 and 12 q ha-1 yield targets by 10.39, 37.65 and 48.18 per cent, respectively, over general recommended dose of sesame.ThesisItem Open Access DYNAMICS OF MICRONUTRIENTS IN CALCARIOUS VERTIC USTOCHREPTS SOILS UNDER AICRP-LTFE(2009-01) VEKARIA LALITKUMAR CHANDULAL; Golakiya B.A.Micronutrients play a vital role in enhancing crop productivity and improving quality of crops. Intensification of agriculture with high yielding crop varieties, continuous use of highly analysed fertilizer restricting supply of organic matter, negligible use of crop residuals and increasing cropping intensity, all together exhausted micronutrients from soils. The deficiencies of micronutrients in Indian soils as well as Gujarat soils were very well recognized with special reference to Cu, Mn, Zn and Fe. Further, different pools were recognized and a number of sequential fractionation procedures were developed to study the relative abundance and importance of different fractions in the soil. Junagadh is one of the centers representing medium black calcareous soil (Vertic ustocrepts). These sub soils are difficult to manage from fertility point of view. Further most of our research information is largely emanated from short term study and unable to answer critical questions about how the intrinsic properties of soils being changed by anthropogenic activities affect the micronutrient resource. In view of above following broad objectives were set : To study the status of micronutrient (Fe, Zn, Mn, Cu) fractions in calcareous Vertic ustrochrepts soils under AICRP-LTFE. To investigate the depletion of micronutrients fractions in the soils under investigation. Modeling the dynamics of micronutrient fractions in the AICRP-LTFE soils. To achieve the forgoing objectives, this investigation initiated which comprised of samples derived from long term fertilizer experiment started 8 years back on Vertic ustocrept calcareous medium black clayey soils of Junagadh. The samples were subjected to fractionation of micronutrients viz., Cu, Mn, Zn and Fe. The micronutrients, their fractions and soil properties were related to various yields and NPKS content from plants. In this part also the data were subjected to correlation analysis, stepwise regression, multiple correlation and path analysis. The LTFE experiment involved twelve treatments including untreated control which was subjected to analysis of variance in order to find out the effect of various treatments on yield, NPKS content and micronutrient fractions and also depletion in a long term cycle of 4 and 8 years. In a long run, treatment differences in groundnut yield diminished while wheat yield showed significantly higher values in T8 after long spell of 8th year. The treatment T3 registered the highest N concentration and T8 the lowest in groundnut pod while T2 recorded highest concentration and T9 the lowest in groundnut haulm. The T8 registered the highest concentration while control the lowest both in wheat grain and straw. In groundnut pod phosphorus concentration decreased while in haulm increased like wise in wheat grain phosphorus concentration was increased but in straw decreased after a period of 8 years. The concentration of potash after 4th year of cycles showed increase while after 8th year cycle it was declined in groundnut and wheat. In groundnut sulphur concentration increased after 4th year while declined after 8th year. In wheat, sulphur concentration decline after 4th and 8th year. From the overall picture with respect to various forms of Cu it can be deduced that there was a decline in the soil Cu levels where a significant decline in most of all important forms. There was a decline in the soil Mn status in the LTFE soils in different form and these was a significant decline in the important forms such as exchangeable Mn, total Mn and residual Mn. Overall mean DTPA available Mn recorded medium values (6.297 ppm) as compared to the critical values. The DTPA available Zn was maintained high quite above critical values (0.5 to 1.0 ppm) and did not indicate any need to supplement Zn nutrient in near future. Particularly DTPA available ferrous showed considerable depletion over time and chemical fertilizers triggered utilization thereby the levels reaching below critical values. Although iron is the most abundant element, its availability needs suitable management practices. The DTPA available nutrients were the predominant form in copper, manganese, zinc and iron. Chemical fertilizers supplemented and enhanced utilization of DTPA available Mn and Cu along with a shift in inter-conversion among forms, over the 4 and 8 years cycles. Correlations Groundnut pod yield and haulm yield exhibited significant positive relationship with DTPA available Cu, exchangeable Mn, per cent available Mn, residual Mn, residual Zn, per cent available Zn, water soluble Fe, residual Fe and per cent available Fe. Obviously wheat grain yield showed significant negative relationship with available Cu, while significant positive relationship with all forms of Mn and Zn and exchangeable Fe, DTPA available Fe, total Fe and available total Fe. Available form of Cu showed positive relationships with nitrogen concentration particularly in wheat grain (cereals), P concentration in groundnut pod and K concentration in groundnut haulm and S concentration in wheat grain and straw. Available Mn facilitated the partitioning of nitrogen towards wheat grain and groundnut pods. Available Mn favored accumulation of K in wheat gain and groundnut pod over the vegetative parts in both the crops. Phosphorus accumulation was promoted in legumes while it diminished in cereals by Zn. The Fe was found to indirectly regulate partitioning between vegetative and reproductive parts via regulating P concentration which was known to influence the osmotic relations. The total Cu was predominantly reflected by DTPA available Cu followed by residual, per cent available and residual. The DTPA available copper showed significant positive correlation with soil pH. The data from correlation studies indicated strong association between DTPA-Mn and its reducible, total, residual, and available total. The DTPA available Mn showed significant positive relationship with many soil properties viz., soil pH, O.C. and available K2O. The DTPA available Zn showed highly significant positive relationship with available total and percent available Zn. The DTPA available Zn also showed significant positive relationship with various soil properties viz., soil pH, EC, O.C., available N, available P and available K2O. The DTPA available Fe displayed a highly significant positive relationship with available total, total and exchangeable forms. The DTPA available Fe recorded significant positive relationship with most of the soil properties viz., Soil pH, EC, O.C., available N and available P. The interactions viz., zinc x iron, manganese x zinc and copper x zinc showed more conspicuous relationships. Regressions The DTPA available micronutrients as influenced by other forms were subjected to stepwise regression and multiple correlation and regression analysis. The prediction models were based on multiple and correlation analysis over a cycle of 1, 4 and 8 years. The stepwise regression analysis indicated that total form in copper, manganese, zinc and ferrous had the maximum impact on DTPA available micronutrients. The stepwise regression analysis of DTPA available micronutrient as the dependent variable and soil properties as the independent variables indicating a low degree of influence. Nevertheless, Properties utilized for analysis soil pH influenced DTPA available Cu, soil O.C. to DTPA Mn and Zn, soil EC and O.C. to DTPA Fe, to the maximum extent. Path Co-efficients The residual Cu form exhibited significant positive correlation with DTPA available Cu. Total and per cent available form of Mn had a direct positive effect on DTPA Mn. The residual Zn and total Zn had a high direct effect on DTPA available Zn. The total ferrous showed a direct positive effect, while reducible ferrous showed a direct negative effect on DTPA available ferrous. spatiotemporal variations according to soil type, land use, agronomic package, cropping patterns and agro-ecological situations. Most of all micronutrients with their forms exhibited in general a negative trend in the long term fertilizer experiment after 8 years.ThesisItem Open Access NITROGEN AND POTASSIUM REQUIREMENT FOR TARGATED YIELD OF SUMMER PEARL MILLET(2009-01) SAKARVADIA HASMUKHRAY LAKHABHAI; Golakiya B. A.A field experiment was conducted on medium black calcareous soil at Instructional Farm, Junagadh and a cluster of field experiments were conducted on farmers‟ fields on with medium black calcareous soils of different villages of Junagadh district to study the “Nitrogen and potassium requirement for targeted yield of summer pearl millet” during summer 2007 and 2008; respectively. The object was to assess the effect of nitrogen and potassium levels on growth, content and uptake of nutrient, yield and yield attributes, quality parameters, and nutrients (N, P, K, Fe, Mn, Zn, Cu) availability as well as to develop targeted yield equations and to verify different yield targets. Twenty fertilization treatments comprising of five levels of nitrogen (0, 40, 80, 120 and 160 kg ha-1) and four levels of potassium (0, 40, 80 and 120 kg ha-1) were investigated. The results of the field experiment revealed that the maximum dry matter accumulation was observed during the period of 60 DAS to harvest (63.59 %) followed by 30- 60 DAS (33.13 %) and 1-30 DAS (3.28 %). In general, the N, P and K content in the plant decreased with advancement of crop growth. In case of micro nutrients, the maximum iron, zinc and copper content in dry stover was observed at harvest but manganese content was highest at 30 DAS. The accumulation of major (N, P, K) and micro (Fe, Mn, Zn, Cu) nutrients by crop was increased with advancement of its growth and age. The dry weight of crop and CGR value were observed maximum under application of nitrogen @ 120 kg ha-1. In respect of yield attributes, the plant height (143.2 cm), number of tiller per plant (5.64), earhead girth (8.13 cm), quality parameters like test weight (8.77 g), protein content (10.11 %) and grain (3206 kg ha-1) and stover (6124 kg ha-1) yield of pearl millet were also recorded highest with application of 120 kg N ha-1. While, ear head length (20.93 cm) and grain: stover ratio (0.544) was recorded higher with maximum dose of nitrogen @160 kg ha-1. The content of all the macro and micro nutrients in plant and grain were not influenced by varying levels of nitrogen application, except nitrogen content; which was found highest in dry stover at 30 DAS and in grain with 120 kg N ha-1. While, the concentration of N in dry stover at 60 DAS and at harvest was observed maximum with 160 kg N ha-1. The uptake of all the macro (N, P, K) and micro (Fe, Mn, Zn, Cu) nutrients was recorded maximum with application of nitrogen @ 120 kg ha-1 at 30 DAS, 60 DAS and at harvest by dry stover yield as well as its uptake by grain and total uptake by crop, except K and Mn uptake by grain, which was observed maximum with 160 kg N ha-1. Increasing levels of nitrogen did not affected the availability of macro and micro nutrients in soil, except nitrogen availability, which was significantly highest at 30 DAS, 60 DAS and at harvest of crop, under higher dose of nitrogen i.e. 160 kg N ha-1 in compared to lower dose of nitrogen application. The dry matter yield of crop at all the growth stages, CGR at 30 DAS and 60 DAS and test weight (8.75 g) were recorded significantly higher under application of 80 kg K2O ha-1. While, plant height (142.5 cm), number of tiller per plant (5.42), grain: stover ratio (0.521), protein content (9.65 %) and grain (3097 kg ha-1) and stover (5893 kg ha-1) yield of pearl millet were obtained higher under application of potash @ 120 kg ha-1. The effect of potassium on ear head girth and length was found non-significant. The content of nitrogen, phosphorus and all the micro nutrient (Fe, Mn, Zn, Cu) in dry stover were not significantly influenced by application of potash at all the growth stages and also in grain. While, the concentration of potassium was observed higher in dry stover at all the growth stages and also in grain under application of potassium @ 120 kg ha-1. The nitrogen uptake by dry stover at all the growth stages as well as its uptake by grain and total uptake by crop, phosphorus uptake at 30 and 60 DAS and K uptake at 60 DAS were obtained maximum with application of 80 kg K2O ha-1. While significantly highest P uptake by dry stover at harvest, grain and its total uptake and K uptake at 30 DAS and at harvest as well as its uptake by grain and total uptake by crop was obtained with application of 120 kg K2O ha-1. The uptake of micro nutrients (Fe, Mn, Zn, Cu) by dry stover yield at different growth stages as well as its uptake by grain and total uptake by crop was recorded higher under application of potash @ 80 kg ha-1, except Cu uptake by grain and Zn uptake by dry stover at harvest, which was observed maximum with 120 kg K2O ha-1. Only the availability of potassium in soil was increased with increasing level of potassium. While other macro and micro nutrients status of soil was not influenced by potash application. The total dry matter yield at 30 DAS and at harvest, CGR at 30 DAS, grain and stover yield of pearl millet, uptake of nitrogen, potassium, iron and manganese by dry stover at 30 DAS, phosphorus at 30 and 60 DAS and copper at 30 DAS and at harvest were recorded significantly higher under application of nitrogen @ 120 kg ha-1 along with 80 kg K2O ha-1. While the maximum CGR value at harvest with N160K120, grain: stover ratio with N160K80 and uptake of phosphorus by grain and its total uptake by crop and iron and manganese uptake by grain with N80K80 treatment. The maximum uptake of K by stover was obtained with N120K120 and so also the total uptake with N80K120 treatment. The plant height, number of tillers per plant, ear head length and girth, test weight, protein content, content of all the macro and micro nutrients in plant at all the growth stages as well as in grain and its availability in soil at all the growth stages were not affected by interacting effects of nitrogen and potassium. The requirement of nitrogen and potassium for producing one quintal pearl millet grain was 3.78 and 2.07 kg, respectively. Pearl millet grain yield were achieved within ± 9.02 to 2.04 per cent variation at different yield targets (18, 24, 30 and 36 q ha-1) from verified trials on basis of derived equation of N (FN = 10.98 x T (yield targets q ha-1) – 0.92 SN) and K (FK2O = 6.48 x T – 0.51 SK). The additional grain yield was obtained at 24 and 30 q ha-1 yield targets by 9.08 and 29.9 per cent, respectively, over general recommended dose of pearl millet.ThesisItem Open Access NITROGEN AND POTASSIUM REQUIREMENT FOR TARGATED YIELD OF COTTON(2006-03) PARMAR KACHARABHAI B.; Golakiya B.A.A field experiment was conducted on medium black calcareous soil at Instructional Farm, Junagadh and second cluster of field experiment was conducted on farmer‟s field with medium black calcareous soils of different villages of Junagadh district to study the “Nitrogen and potassium requirement for targeted yield of cotton” during kharif 2003-04 and 2004-05. The object was to assess the effect of nitrogen and potassium levels on growth, content and uptake of nutrient, yield and yield attributes, quality of seed cotton, and nutrients (NPK) availability as well as to developed targeted yield equations and to verify different yield targets. Twenty one fertilization treatments from four levels of nitrogen (90, 120, 150 and 180 kg ha-1) and five levels of potassium (30, 60, 90, 120 and 150 kg ha-1) and one absolute control in triplicate were under investigation. The results of field experiment revealed that the dry yield (g plant-1) of leaves, shoot, root, total plant and CGR was increased with nitrogen levels and recorded maximum values under 180 kg N ha-1. Potassium did not influenced the growth parameters significantly. The concentration of nitrogen in leaves and shoot at 90, 120 and 150 days and that in stalk was significantly influenced by nitrogen levels while the concentration of K in the leaves and shoot at 30, 60, 90 and 120 days increased with potash levels. The uptake of nitrogen, phosphorus and potassium by leaves, shoot and root at different growth stages and nitrogen and potassium uptake by seed cotton and stalk was recorded higher under application of nitrogen @ 180 kg ha-1. Similarly, the maximum uptake of nitrogen and potassium was recorded at 150 kg K2O ha-1 due to higher seed cotton yield. Plant height, bolls per plant, seed cotton yield and total yield were obtained significantly higher at 180 kg N ha-1 which remained at par with 150 kg N ha-1 whereas the branches per plant, bolls per plant and seed cotton yield were recorded higher under 150 kg K2O ha-1. The quality parameters of seed cotton viz., lint index, oil content, fiber elongation and short fiber index (SFI) were significantly influenced by nitrogen while bundle strength (Tenacity) and fiber elongation were influenced by potassium levels. The interaction effect of N and K was not observed on yield and yield attributes but it affected the quality parameters viz., seed index, micronair and fiber elongation. In respect of the distribution of dry matter and nutrients, the relative dry weight of leaves contributed higher to total dry matter than shoot and root under nitrogen level, where as K application @ 150 kg ha-1 resulted in higher relative dry weight of shoot. The content of nitrogen was recorded higher in leaves (0.91-1.65 %) followed by shoot (0.63-0.87 %) and root (0.38-0.64 %) while content of K was higher in shoot (0.52-1.48 %) compared to root (0.47-1.07 %) and leaves (0.41-1.10 %) during growing period. In general, the concentration of nitrogen and potassium diminished with the age of plant. The requirement of nitrogen and potassium for producing one quintal seed cotton was 4.48 and 2.30 kg, respectively. Seed cotton yield were achieved within ± 0.96 to 6.38 per cent variation at different yield targets (18, 22, 26 and 30 q ha-1) from verified trials on basis of derived equation of N (FN = 16.95 x T-0.93 SN) and K (FK2O = 8.79 x T-0.42 SK). The additional seed cotton yield was obtained at 26 and 30 q ha-1 yield targets by 15.79 and 30.0 per cent, respectively, over general recommended dose of cotton.ThesisItem Open Access CHARACTERIZATION, CLASSIFICATION AND EVALUATION OF SOIL AND WATER RESOURCES ACROSS THE TOPOSEQUENCES OF SOUTHERN SAURASHTRA(2005-02) SAVALIA, SHANTILAL G.; Gundalia, J.D.Sixty three soil samples from sixteen representative pedons of four toposequences viz., Hiran, Shingoda, Machhundri and Rayadi in southern Saurashtra across the five land forms viz., hill slopes, upper piedmont, lower piedmont, piedmont plain and coastal plain were collected during 2002-03 to study the morphological, mineralogical, physical, hydrological and chemical characteristics, taxonomic classification of soils, underground water quality and soil-water and climatic conditions with the aim to evaluate soil-site suitability and water resources for different crops. The results reveal that the soils of different toposequences across the land forms of southern Saurashtra have developed from basaltic and Gaj bed milliolitic lime stone parent materials from hill slope to lower piedmont and alluvium in piedmont plain and coastal plain. The soils have clay loam to clayey texture, moderate to strong sub angular blocky structure and very dark grayish (10YR 3/1M) to brown (10YR 5/3M) colour. Smectite was the dominant clay mineral, while plagioclase and quartz were dominant in silt and sand fractions. The total sand, silt and clay content varied from 20.56 to 51.87, 20.20 to 43.98 and 16.40 to 49.45 per cent with the mean of 34.12, 33.57 and 32.31 per cent, respectively. The proportion of silt content in soil separate increased with the decrease in elevation. The bulk density varied from 1.28 to 1.57 Mg m-3 with the mean of 1.41 Mg m-3. Higher bulk density was recorded from lower piedmont and coastal plain. The soils of upper piedmont were highly expandable as compared to other land slopes. The maximum water holding capacity (MWHC), saturated hydraulic conductivity and infiltration rate of soils decreased with the decrease in elevation from hill slope to coastal plain. The total plant available water capacity (PAWC) and water storage capacity (WSC) of the soils varied from 0.063 to 0.767 and 0.179 to 1.539 m ha-1 with mean of 0.229 and 0.537 m ha-1, respectively which were found in the order of piedmont plain > coastal plain > lower piedmont > upper piedmont > hill slope. The PAWC/ WSC ratio ranged from 0.346 to 0.498 with the mean of 0.407 indicating 41 per cent available water for plant out of total water storage capacity of the soils of 0.537 m ha-1. In general, the pH, EC, O.C. and CaCO3 ranged from 7.70 to 8.59, 0.18 to 1.06 dSm-1, 0.12 to 0.93 per cent and 1.96 to 47.05 per cent with the mean of 8.13, 0.36 dSm-1, 0.49 per cent and 17.24 per cent, respectively indicating that the soils were moderately alkaline in reaction, low in EC and O.C. status and highly calcareous in nature. The values of pH and EC increased gradually along the elevation gradient from hill slope to coastal plain. While traversing from hill slopes to coastal plain, a gradual decrease in the content of organic carbon was observed. The CaCO3 content increased down the slope and it was maximum (22.42 per cent) in coastal plain. The CEC varied from 16.11 to 28.80 cmol (p+) kg-1 with the mean of 24.39 cmol (p+) kg-1. However, no definite trend in distribution of CEC from hill slope to coastal plain was observable. The proportion of exchangeable cations were observed in order of Ca2+ > Mg2+ > Na+ > K+. The BSP and ESP ranged from 90.15 to 93.50 and 6.38 to 14.90 with the mean of 92.47 and 9.67, respectively. The ESP > 10.0 in lower piedmont to coastal plain and has the potential of achieving alarming proportions, if neglected. The pHs and ECe ranged from 7.79 to 8.16 and 0.75 to 3.66 dSm-1 with mean of 7.96 and 1.32 dSm-1, respectively indicating that the soils were non-sodic and non saline except some part of coastal plain. The pHs and ECe increased with decrease in elevation from hill slope to piedmont plain and hill slope to coastal plain, respectively, The proportion of water soluble Na+ was dominant followed by Mg2+, Ca2+ and K+. The distribution of total water soluble cations increased with decreasing topography. The CO32- was absent in water soluble anions in saturation extract, while Cl- was dominant followed by HCO3-. The HCO3-, Cl- and SAR increased gradually with decreasing topography. The soils were low in available N and P2O5 and medium in available K2O. The available N decreased with decrease in elevation, while reverse trend was observed in case of available P2O5. The soils were high in available Fe, Mn, Zn and Cu micronutrient cations. The soils were classified as Lithic Ustorthents, Typic Ustorthents, Vertic Ustochrepts, Typic Ustochrepts, Typic Ustropepts, Fluventic Ustropepts, Fluventic Calciustepts and Calcic Ustropepts at sub groups level. Now Ustochrepts are named as Haplustepts as per Soil Survey Staff (2003). The pH and EC of underground water increased with decreasing elevation. The pH and SAR of underground water increased with increase in EC. As per the limits proposed by Richards (1954), the underground water for irrigation over hill slope, upper piedmont and lower piedmont, was placed under safe class of C2S1 and C3S1 while the piedmont plain and coastal plain were in the doubtful class of C4S2 and C4S3. In general, the irrigation water of whole southern Saurashtra was placed under C3S1 water quality class except that of the coastal plain. The guidelines for its suitability and management strategy are discussed in detail in the text. The climatic condition of southern Saurashtra was recorded. The natural soil, water and climatic constraints were also identified in the study area. The soils of pedon P1 were in sustainable class S2, while the pedons P2 to P8, P10 to P13 and P15 were in sustainable with high input (S3) class. However, the soils of pedons P9, P14 and P16 were under class S4, i.e. sustainable with alternate land use. The mean score of weight factors of four toposequences were found in order of Hiran (26) < Shingoda (27) < Machhundri (28) < Rayadi (29) indicating that the soils constraints / limitations increased from west to east direction in southern Saurashtra. The soils of hill slope and piedmont plain area were facing overall relatively less soil constraints as compared to upper piedmont, lower piedmont and coastal plain areas. The remedial measures were discussed to overcome the soil and water constraints in different land slopes for soil sustainability. The reserve water and water balance varied from 0.136 to 0.518 and -0.203 to +0.653 m ha-1 with the mean of 0.308 and +0.253 m ha-1, respectively. The negative water balance in piedmont plain (-0.323 m ha-1) and coastal plain (-0.203 m ha-1) lead to ground water depletion every year and ultimately resulted in the ingress of seawater. Alternate land use plans for various land forms under study have been suggested for their better management. Thus, rabi sorghum is most suitable in Borvav (P2) and sugarcane, mustard and sorghum in Devali (P7) village were found to be highly suitable (S1) crops. Whereas, soils in Jamwala (P5), Maljinjava (P3), Kareda (P6), Judavadali (P10), Chotara (P15), Devali (P7) and Chauhani Khan (P8) villages were suited for soybean, while in soils of Maljinjava (P3), Chotara (P15), Devali (P7), Chauhani Khan (P8) and Rampara (P12) villages, sunflower can be introduced as these soils have been moderately suitable (S2).ThesisItem Open Access DYNAMICS OF MICRONUTRIENT FRACTIONS IN THE CALCAREOUS SOILS OF SAURASHTRA REGION(2004-11) NARIYA, JAYSUKH N.; Golakiya, Balubhai A.Micronutrients play a vital role in enhancing crop productivity and improving quality of crops. Intensification of agriculture with high yielding crop varieties, continuous use of highly analysed fertilizer restricting supply of organic matter, negligible use of crop residuals and increasing cropping intensity, all together exhausted micronutrients from soils. The deficiency of micronutrients in Indian soils as well as Gujarat soils were very well recognized with special reference to Cu, Mn, Zn and Fe. Further, different pools were recognized and a number of sequential fractionation procedures were developed to study the relative abundance and importance of different fractions in the soil. The majority of medium black soils of Saurashtra region are calcareous in nature derived from trap basalt in semi-arid climate. The calcareousness is a unique property of soils which affects the physical and chemical properties, nutrient availability and plant growth. Almost 10 agro-ecological situations of Saurashtra region have been identified which vary in soil resource. Among them, Junagadh is one of the centers representing medium black calcareous soil (Vertic Ustocrepts). These sub soils are difficult to manage from fertility point of view. Further most of our research information is largely emanated from short term study and unable to answer critical questions about how the intrinsic properties of soils being changed by anthropogenic activities affect the micronutrient resource. In view of above following broad objectives were set : 1. To determine the turn over of micronutrients fractions in the different soil groups of Saurashtra region. 2. To investigate the status of micronutrients (Cu, Mn, Zn and Fe) fractions in medium black calcareous soils (Vertic Ustocrepts) of Junagadh under LTFE. 3. Modeling the dynamics of micronutrients fractions in these soils. To achieve the forgoing objectives whole work is divided in two parts. The part one (I) comprised regular monitoring of the fertility since 1990. Sampling were made from the soils of predetermined survey number at ten years intervals. The samples of 1990 and 2000 were subjected to fractionation of micronutrients viz., Cu, Mn, Zn and Fe. Various soil properties such as soil pH, soil EC, soil CaCO3, soil CEC, soil ExCa, soil OC, soil clay, soil ESP, soil available nitrogen, soil available phosphorus, soil available potash and soil-heat soluble sulphur were also analysed. Whole set of data from ten different soil groups of Saurashtra region and changes in a long term cycle of 10 years were subjected to various statistical analyses including correlation among fractions, between the forms and with properties, stepwise regression, multiple correlations and path analysis with DTPA available micronutrient as the dependent variable to investigate the influence of long term cycle, interaction and soil properties on available form of micronutrients vis-à-vis finding out the depletion of predominant component of available micronutrients and interactions among various forms and fractions of soil groups as well as districts. Second part (II) of investigation comprised the samples derived from long term fertilizer experiment initiated 20 years back on Vertic Ustocrept calcareous medium black clayey soils of Junagadh. There were no gross additions of micronutrients in this groundnut-wheat-sorghum cropping system. The micronutrients, their fraction and soil properties were related to various yields and NPK content from plants. In this part also the data were subjected to correlation analysis, stepwise regression, multiple correlation and path analysis. The LTFE experiment involved six treatments including untreated control which was subjected to analysis of variance in order to find out the effect of various treatments on yield, NPK content and micronutrient fractions and also depletion in a long term cycle of 10 and 20 years. I. SOIL GROUP ANALYSIS : Status and Depletion : In zinc, copper and ferrous the predominant component of available total was DTPA available form while in case of manganese it was reducible form. Considering primarily the predominant component, the status of copper was highest in soil group RAD and SBSS in 1990 and 2000, respectively, manganese in soil group SBTB and DBTB in both years, zinc displayed variable picture while soil group MBTB which recorded highest values for iron. So far as depletion is concerned soil group SBLS registered maximum depletion in copper and manganese, iron in soil group MBLS and MBTB while zinc displayed a variegated picture. In certain soil groups on the contrary there was an increase over time. Soil group SBSS and DBTB recorded an increase in copper, manganese and iron along with some other groups. In case of zinc almost all groups registered an increase in a span of ten years. Correlations : The DTPA available micronutrients showed strong positive relationship with percent availability thereby rendering its predominance in most of the soil groups with some exceptions. Soil properties showed a variegated picture and different relationships were found to vary in direction and magnitude in various soil groups. Soil groups specific interactions were evident but in general copper and manganese with special reference to DTPA available form were correlated maximum while copper and zinc the least between them with exceptions in some soil groups. Ferrous and zinc also showed lesser extent of interactions. Regressions : The prediction models were worked out for DTPA available forms as influenced by the other representative forms in the years 1990, 2000 and pooled utilizing the multiple correlation and regression analysis. The pooled data were also subjected to stepwise regression analysis which indicated that DTPA available copper was mostly influenced by total, residual and water soluble, whereas DPTA available manganese by exchangeable form and DTPA available zinc and ferrous by different forms in different soil groups. As in forms, the DTPA available micronutrients as influenced by various soil properties were also subjected to multiple correlation analysis in the year 1990, 2000 and pooled and prediction models were derived. So far as stepwise regression analysis of pooled data are concerned soil properties could explain the behaviour of DTPA available micronutrients viz., Cu, Mn, Zn and Fe to little extent. Path Co-efficients : Path analysis of DTPA available micronutrients as influenced by other forms in the year 2000 revealed that total content of micronutrient had a direct positive effect while residual forms had a direct negative effect which was because of its strong indirect negative effect through the total content. The path co-efficient analysis of DTPA available micronutrients as influenced by various soil properties revealed that the values of residual component were very high in most of soil groups and soil property could explain only a little of the behaviour of DTPA available micronutrients. II. LONG TERM FERTILIZER EXPERIMENT : The differences in yield diminished in groundnut while T6 recorded highest values in wheat as well as sorghum all through. The N content were highest in T6 in a long run in groundnut and wheat grain while in straw it declined. Phosphorus in groundnut increased while that in cereals declined over 20 years. Potash also followed more or less same trend. Particularly manganese exhibited an overall decline with time. Even DTPA available Mn registered below the critical values. If predominant form of bioavailable manganese is reducible one, then only the deficiency symptoms are not observed. Nevertheless, whole spectrum warrants a need to supply suitable Mn nutrient. Although copper also showed a decline but DTPA available copper was maintained well above the critical value. Zinc also rendered a similar picture and application of chemical fertilizers supplemented as well as enhanced the utilization of zinc. Particularly DTPA available ferrous showed considerable depletion over time and chemical fertilizers triggered utilization thereby the levels reaching below critical values. Although iron is the most abundant element, its availability needs suitable management practices. The DTPA available nutrients were the predominant form in copper, zinc and iron while reducible was predominant in manganese. Chemical fertilizers supplemented and enhanced utilization of DTPA available Mn and Cu along with a shift in inter-conversion among forms, over the 10 and 20 years cycles. Correlations : Groundnut pod yield was significantly related with percent available Mn, total and residual zinc and percent available iron and available total iron. Available total of Cu, available Mn, DTPA available zinc and an overall available iron predominantly showed positive relationship with soil properties. Correlation study indicated that Zn regulated partitioning of nitrogen towards grain and of potassium towards the vegetative growth. Phosphorus accumulation was promoted in legume while demoted in cereals by zinc. Available iron regulated concentration of nitrogen toward grain in cereals and phosphorus toward legumes, and potash in wheat grain and groundnut pods. Available copper showed positive relationship with nitrogen and potassium in wheat grains, and phosphorus in groundnut. Available Mn behaved differently with phosphorus concentration exhibiting positive relationship in groundnut and negative relationship in wheat and sorghum. Available Mn by virtue of reducible forms favoured accumulation of potash in wheat grain and groundnut pod over vegetative parts. Manganese revealed an overall negative relationship with NPK in groundnut, wheat and sorghum. Copper showed positive relationship with potash in groundnut haulm and inverse relationship with wheat straw. The DTPA Zn was positively related with phosphorus uptake in groundnut haulm while other forms showed negative relationship with N and P in sorghum, wheat straw and groundnut haulm. In iron relationships varied with form. The DTPA available and reducible form showed significant positive relationship with phosphorus uptake in groundnut haulm. The interactions viz., Iron x copper, iron x zinc and copper x zinc showed more conspicuous relationships. Regressions : The DTPA available micronutrients as influenced by other forms were subjected to stepwise regression and multiple correlation and regression analysis. The prediction models based on multiple regression and correlation analysis over a cycle of 1, 10, 20 years were presented. The stepwise regression analysis indicated that exchangeable form of copper, manganese and zinc along with the total had the maximum impact on DTPA available micronutrients. On the contrary in ferrous reducible forms had the maximum influence. The stepwise regression analysis of DTPA available micronutrients as the dependent variable and soil properties as the independent variable indicated very high residual values thereby indicating a low degree of influence of the soil properties. Nevertheless, soil EC, soil OC and soil pH influenced DTPA available Cu, Mn, Zn and Fe, respectively, to some extent. Path Co-efficients : Zinc was explained the least and copper the most based on the independent variables (various forms) included in the analysis. The total micronutrients had the maximum direct effect on DTPA available micronutrient in Fe, Zn and Mn. Although the relationships of exchangeable and reducible forms with DTPA available form were significantly positive but direct effect were either negative or negligible. This might be due to their high indirect positive effect through total form of zinc and ferrous. The dynamics of micronutrients with all its form exhibited spatiotemporal variations according to soil type, land use, agronomic package, cropping patterns and agro-ecological situations. Except that of Zn all other micronutrients with their forms exhibited in general a negative trend over a period of 10 years and so also in the long term fertilizer experiment after 20 years.ThesisItem Open Access FRACTIONATIONS OF SOIL ORGANIC MATTER IN LONG TERM FERTILIZER EXPERIMENT(2005-03) CHODVADIYA, MAHESH B.; Golakiya, Balubhai A.The study has been carried out for fractionation of soil organic matter in groundnut-wheat- jowar (fodder) cropping sequence under long-term fertilizer experiment (1979-2000) on a medium black calcareous clay soil at Instructional Farm, College of Agriculture, Junagadh Agricultural University, Junagadh. There were six treatments viz., control, FYM @ 25 t ha-1, ½ NP, ½ NP + K, NP and NP + K and from each treatment soil samples were collected in the years 1980, 1990 and 2000 analysed for active, passive and slow pools. The data were analysed for correlation, regression and path co-efficient statistical tools. The pools of soil organic matter concentrate as soil organic carbon under the treatments application of FYM @ 25 t ha-1 followed by NP + K treatment in the year 1990. In the context of active pools of SOM, maximum of water soluble carbon and water soluble carbohydrates were recorded under FYM application @ 25 t ha-1 in the years 1990 and 2000, respectively. Vigorous flush of carbon mineralization was achieved under application of FYM @ 25 t ha-1 in the year 1980. Both the SMBC and SMBN were found low under application of full doze of N and P along with potassium in the year 1990 whereas SMBP in the same year were low with N and P without potassium. Maximum activity of dehydrogenase was observed in the year 1990 under NP treatment. Among the passive pools, maximum humic acid, brown humic acids, gray humic acid, fulvic acid, hymatomelanic acid and humin were observed in the year 1990 with application of FYM @ 25 t ha-1. The slow pools of SOM, improved percent of water stable aggregates and organic carbon application of FYM @ 25 t ha-1. Positive association among humic acid, brown humic acid, gray humic acid, fulvic acid, hymatomelanic acid and humin was observed under the treatments namely FYM @ 25 t ha-1, NP, ½ NP, ½ NP + K, NP + K. Positive association of soil microbial biomass carbon with dehydrogenase activity and water soluble carbohydrates was observed under control, ½ NP and NP + K treatments. Positive association of soil microbial biomass nitrogen was observed with soil microbial biomass phosphorus under control and with water-soluble carbohydrates under treatments ½ NP + K and NP + K. Regression of passive pool was significant in three treatments Viz., control, FYM @ 25 t ha-1 and NP + K. During the year 1980, a combine impact of passive pools of humic acid and humin over soil organic carbon contributed to a maximum level in the three treatments. During the year 1990, a combine impact of passive pools of humic acid and humin over soil organic carbon was contributed to a maximum level under NP + K treatment whereas combine influence of humic acid and hymatomelanic acid over soil organic carbon to the maximum tune under FYM @ 25 t ha-1. During the year 2000, a combine impact of passive pools of humic acid and fulvic acid over soil organic carbon contributed to a maximum level in the three treatments. During the year 1980, a combine impact of active pools viz., SMBC and SMBP over soil organic carbon contributed to a maximum level in all the three treatments. During the year 1990, a combine impact of active pools of SMBC and SMBN over soil organic carbon contributed to a maximum level under control treatment whereas combined influence of SMBC and SMBP over soil organic carbon to the maximum tune under FYM @ 25 t ha-1. During the year 2000, a combine impact of active pools of SMBN and SMBP over soil organic carbon contributed to a maximum level in the three treatments. Path analysis of active as well as passive pools of soil organic matter have generated useful information. The maximum direct effect was contributed by humin and their indirect effect via fulvic acid under FYM treatment. The humic acid and their indirect effect via humin was observed under NP + K on soil organic carbon. Residual variation was maximum under NP + K treatment. The maximum direct contribution of DHA and indirect effect via SMBN under the FYM and NP + K treatment was observed on soil organic carbon. The maximum direct effect on SOC was contributed by GHA and their indirect effect via humin under FYM treatment. Humin and their indirect effect via GHA was observed under NP + K treatment on soil organic carbon. The maximum direct effect was contributed by SMBC under FYM treatment and by WSC under NP + K treatment on soil organic carbon. The maximum direct effect was contributed by HA and their indirect effect via BHA under FYM treatment. The BHA and their indirect effect via humin followed by HA under NP + K treatment on fulvic acid. The organic and inorganic treatments produced maximum direct effect by SMBC and its indirect effect via SMBN under FYM; and by SMBC and its indirect effect via DHA under NP + K treatments on fulvic acid. The maximum direct effect on SOC was contributed by humin under FYM and by HA under NP + K treatments and their indirect effect via FA on fulvic acid in both the treatments. Residual variation was observed maximum under NP + K treatment. The maximum direct effect was contributed by SMBN and their indirect effect via WSC under both the treatments. In this path, highest residual variation was contributed under FYM application @ 25 t ha-1 compared to application of full doze of NP along with K. Maximum direct effect of the organic and inorganic treatments was contributed by humin in both the treatments and their indirect effect via FA under FYM and via HA under NP + K treatments. In this path, highest residual variation was contributed under application of full doze of NP along with K comparative to FYM application @ 25 t ha-1. The maximum direct effect was contributed by WSC and their indirect effect via SMBN under FYM and by SMBN and their indirect effect via WSC under NP + K treatments. In this path, highest residual variation was contributed under application of full doze of NP along with K comparative to FYM application @ 25 t ha-1. Thus FYM application @ 25 t ha-1 improved active, passive and slow pools of SOM. Also, improvement of SOM pools was very slow during 1980, highest during 1990 and further decreased during 2000 but still higher than that of year 1980 in the long-term fertilizer experiments.