DTPA Zn Research Articles

Soil Chemical Properties and Nutrient Dynamics under Different Legume-based Agroforestry Systems in Semi-arid Conditions of Haryana

Background: In order to support livelihoods, enhance food security, restore ecosystem services, and reduce pressure on forests, soil fertility can be improved by utilizing alternative land-use systems, such as agroforestry. Methods: The present study was conducted to investigate the effect of different agroforestry systems on soil chemical properties and nutrient availability (macro and micro) during different seasons in Hisar, Haryana. Different systems include Poplar (Populus deltoides), Eucalyptus (Eucalyptus tereticornis), Melia (Melia composita), Shisham (Dalbergia sissoo) based agroforestry system (Cowpea-Wheat) and sole cropping of Cowpea-Wheat (as control). Soil samples were collected from 0-15 and 15-30 cm of soil depth during five seasons i.e., winter, spring, summer, rainy and autumn. Result: Soil EC, SOC and available macronutrients and micronutrients were significantly affected by the depth of sampling, systems and seasons while soil pH was not significantly affected by seasons. Lower soil pH and EC was observed from agroforestry systems as compared to sole cropping. Soil Organic Carbon, availability of N, P, K and S was significantly higher under tree based systems as compared to control. Maximum DTPA extractable Mn, Zn and Cu was observed under poplar based system while highest DTPA extractable Fe was observed under Melia based system during both the years. Significantly higher SOC and nutrient availability was observed during autumn, rainy and spring seasons as compared to winter and summer seasons, while reverse trend was observed for soil pH and EC among the seasons. Soil Organic Carbon, availability of macro and micronutrients decreased with increase in soil depth. Overall, the soil chemical properties and nutrient status of soil were comparatively better under tree based systems than sole cropping of Cowpea-Wheat.

Mehlich 3 as an indicator of grain nutrient concentration for five cereals in sub-Saharan Africa

Context or ProblemSoil testing for available nutrients is an important tool to determine fertilizer rates, however many standard methods test the availability of a single nutrient only. In contrast, Mehlich 3 (M3) is a multi-element test for predicting crop yield responses to the addition of macro and micronutrients. However, the M3 test has rarely been validated against crop nutrient concentrations, which limits its application for dietary improvement studies in sub-Saharan Africa. Objective or Research QuestionThe primary objective was to test how well the M3 nutrient concentrations corresponds to grain nutrient concentrations as an indicator of plant nutrient status and grain quality. A secondary objective was to compare the performance of the M3 test with other extraction tests. MethodsThis study used 1096 paired soil and crop samples of five cereals: maize, rice, sorghum, teff and wheat, covering a broad range of soil types and soil properties in Ethiopia and Malawi (e.g., pH 4.5 - 8.8; Olsen P < 1 - 280 ppm). The samples were selected from a larger collection based on “high” or “low” grain nutrient concentrations in the crop, and the respective soil available nutrients were measured with M3 and other extraction tests: CaCl2 (P, K, Mg, Mn), Ca(NO3)2 (K and Mg), Olsen P, sequential extraction (S), and DTPA (Mn, Fe and Zn). ResultsThe M3 concentrations followed the trend of the “high” and “low” grain concentrations in nearly all nutrients and crops, and this was statistically significant in teff and wheat for all nutrients. The results were best for macronutrients, and slightly less good for micronutrients, probably because the concentration of micronutrients in the selected soil samples was generally quite low. Compared to the other multi-element extractant (CaCl2), the M3 test corresponded better to grain concentrations of K and Mg, and equally well to Olsen P, sequential extraction (S), and DTPA predictions of P, S, Zn and Fe, respectively. M3 extracted much greater concentrations than the other tests, and this was more pronounced in alkaline soils. ConclusionsGiven that the M3 test corresponded well to grain nutrient concentrations across a range of soils and crops in sub-Saharan Africa (SSA), we conclude that it can be considered a universal test for plant nutrients. We also proposed thresholds for M3 values, defining below optimum, optimum and above optimum soil fertility status. Implications or SignificanceThese results validate the use of the M3 test to assess soil fertility and develop fertilizer recommendations for improved produce quality to enhance diets in SSA.

Soil Quality Index for Different Cropping Systems in Northwestern Himalaya Region of India

Background: A study was conducted to examine the impact of soil quality under different cropping systems in Mid hill conditions of Himachal Pradesh”. The study was carried out to ascertain the physical, chemical and biological properties of soils under prevalent cropping systems maize- wheat, rice- wheat and vegetable based in different in mid hill conditions of northwestern Himachal Pradesh.&#x0D; Methods: On the basis of representative 90 soil samples from two depths i.e. 0-0.15 m and 0.15-0.30 m were collected. Soil samples were analyzed for their physical, chemical and biological properties and key indicators were identified using multivariate statistical analysis for computing the soil quality index.&#x0D; Results: Soil reaction across various sites under present study was 5.30-6.70. Higher salt accumulation (EC) was observed under vegetable based cropping systems as compared to those of cereal based. Organic carbon was medium to high and available N, P and K contents were in low to medium range. DTPA Fe, Mn, Zn and Cu were observed sufficient, whereas total Fe, Mn, Zn and Cu were recorded higher in cereal and vegetable based cropping system. Microbial biomass carbon, microbial biomass nitrogen, potentially mineralizable nitrogen and soil respiration were low to medium in all cropping systems.&#x0D; Conclusion: Soil quality index was 1.00 under vegetable based cropping system as compared to the cereal based cropping systems.

Effect of Organic Manure and Gliricidia leaf Extract on Soil Properties after Harvest of Green Gram under Organic Farming

A field experiment was conducted during the summer season of 2022 to find out the influence of organic manure and Gliricidia leaf extract on soil fertility under green gram at the organic farm, Navsari Agricultural University, Navsari, Gujrat. The experiment site was high in organic C content (0.73 %), medium in available nitrogen (257.96 kg/ha) and phosphorus (27.14 kg/ha) while high in available potash (579.13 kg/ha) with pH 7.50 and EC 0.28 dS/m. The result indicated that available N was observed to significantly maximise under the application of 100% RDN through Compost + GLE @500 l/ha at 20, 40 and 60 DAS while available K2O and DTPA extractable Fe were significantly maximum under the application of 100% RDN through Compost + 2% GLE through the foliar spray. Soil pH, EC, organic C, available P2O5, DTPA extractable Mn, Zn, and Cu were not affected significantly due to different treatment comprising various organic sources.

Potential of montmorillonite and humus-like substances modified montmorillonite for remediation of Pb and Zn-contaminated soils

Pb and Zn pollution for soil are becoming more and more serious, strengthening the treatment of contaminated soils is conducive to the sustainable development of soil. In this study, the humus-like substances modified montmorillonite (HLS-MMT) were synthesized to remediate the Pb and Zn-contaminated soils. The application of HLS-MMT in simulated and actual contaminated soil were carried, and the long-term stability of HLS-MMT was evaluated. The results showed that the mobility, bioavailability and leachability of heavy metals (HMs) significantly decreased after remediating by HLS-MMT. Compared with MMT, the TCLP leaching ratio (TLr) of Pb and Zn reduced by 9.27–13.96% and 10.3–13.18%, while the DTPA effectiveness (DEr) Pb and Zn reduced by 9.11% and 8.76% in simulated soil, respectively. Moreover, the aging experiments proved that HLS-MMT possessed a stability to resistance the freeze-thaw cycles, wet and dry alternation, and acid rain leaching. This article provides some theoretical basis for the soil remediation.

Interactive effect of land use systems on depth-wise soil properties and micronutrients minerals in North-Western, India

Micronutrients play a vital role in improving growth and performance of different crops. Management of soil micronutrients for better crop production needs sound understanding of their status and causes of variability. Therefore, in order to evaluate the changes in soil properties and micronutrient contents of soils, an experiment was conducted with soil samples from six soil depths i.e. 0-10, 10–20, 20–40,40-60, 60–80 and 80–100 cm of four prominent land-use systems viz. forest, horticulture, crop land and barren land. Amongst these, the maximum contents of OC (0.36%), clay (19.4%), DTPA-Zn (1.14 mg kg−1), Fe (11.78 mg kg−1), Mn (5.37 mg kg−1), Cu (0.85 mg kg−1) and Ni (1.44 mg kg_1) were observed in soils of forest land use system followed by horticulture, crop land and barren land, respectively. Also, soils of forest landpossessed 29.5, 21.3, 58.4, 51.8 and 44.0% higher DTPA-Zn, Fe, Mn, Cu and Ni as compared to crop land use system. Interactive influence of land use systems and soil depths on distribution of DTPA extractable micronutrients was found to be positive with maximum content at 0–10 cm depth of forest land use and lowest at 80–100 cm of barren land use system, respectively. Correlation analysis explicit positive and significant relationship of OC with DTPA Zn (r = 0.81), Fe (r = 0.79), Mn (r = 0.77), Cu (r = 0.84) andNi (r = 0.80), whereas the correlation results among DTPA micronutrients indicated the highest positivecorrelation of Ni with Cu (r = 0.95) and Mn (r = 0.93) followed by Fe with Zn (r = 0.93). Therefore, inclusion of forest and horticulture land use in crop lands or shift of land use from forest based to crop land resulted in renewal of degraded soil which could be beneficial for enhancing agricultural sustainability.

Soil Fertility Status under Soils of Sugarcane-Ratoon-Wheat Cropping System of Meerut District of Uttar Pradesh, India

The present study was undertaken to assess the soil fertility status os soils under sugarcane-ratoon-wheat cropping system. Soil samples were collected from farmers fields at three depths viz., 0-15 cm, 15-30 cm and 30-45 cm and analysed for various soil properties. Results revealed that soils were sandy clay loam to clay loam in texture, neutral in soil reaction and non saline in salt content. Mean values of CEC 15.96, 13.13 and 10.80 C mol (p+) kg-1, SOC 4.57, 3.93 and 2.95 g kg-1, available nitrogen 263.01, 209.90 and 173.73 kg ha-1, available phosphorus 15.37, 12.49 and 9.00 kg ha-1, available potassium 156.43, 118.16 and 102.11 kg ha-1, DTPA Zn 0.49, 0.35 and 0.21 mg kg-1, DTPA Fe 9.53, 7.71 and 5.28 mg kg-1, DTPA Mn 8.20, 6.80 and 5.20 mg kg-1 and DTPA Cu 0.99, 0.74 and 0.56 mg kg-1 were recorded at 0-15 cm, 15-30 cm and 30-45 cm, respectively. Soils under this cropping system were low in available nitrogen content and medium in available phosphorus and potassium content. Among DTPA extractable micronutrients soil were deficient in available zinc while sufficient in available iron, manganese and copper content.

Influence of Iron Nutrition on Soil Properties, Uptake and Yield of Soybean Grown on Iron Deficient Inceptisol

Iron (Fe) is an essential micronutrient for optimum growth and yield of crop. In calcareous soils availability of Fe is low, to correct Fe deficient soil application of Chelated Fe-EDTA is often recommended to avoid the possible nutritional disorder due to antagonistic effect of Fe with other cationic micronutrients. The present study was initiated with an objective to evaluate response of soybean crop to soil and foliar application of iron. The experiment was carried out at Agricultural Research Station, Kasbe Digraj, Dist: Sangli (MS) during kharif 2018-19. The experimental soil was alkaline, calcareous, clay in texture, low in available nitrogen, phosphorus, very high in available potassium and deficient in iron. The experiment was laid out in randomized block design with eight treatments and three replications. The treatments comprised of common application of NPK fertilizers in conjunction with 10 t FYM ha-1, soil application of FeSO4 @ 10 and 20 kg ha-1 with and without 0.2 per cent spray of chelated Fe. The results revealed that the soil pH and electrical conductivity did not differ due to different treatments however, the organic carbon content was found to be slightly improved over control. The free calcium carbonate percentage in soil also found to be statistically non-significant although it revealed slight decline from the initial value due to different iron nutrition treatments. General recommended dose of fertilizers +Soil application of FeSO4 @ 20 kg ha-1 + two foliar sprays of chelated Fe @ 0.2 per cent at 30 and 50 DAS (T8) recorded significantly higher available N, P and DTPA Fe over control treatment whereas, available K, DTPA Zn, Mn and Cu were found to be statistically non-significant due to different treatment of iron nutrition along with NPK fertilizers and organic manure. Significantly highest total uptake of N, P, K, Fe, Mn, Cu and Zn by soybean was exhibited in T8 which was either equivalent or statistically at par to GRDF + soil application of FeSO4 @ 10 kg ha-1 + two foliar sprays of chelated Fe @ 0.2% at 30 and 50 DAS (T7). In general, all the treatments of iron nutrition were statistically at par in context of soil nutrient and nutrient uptake by soybean crop. Significantly higher grain yield (2493 kg ha-1 ), straw yield (3779 kg ha-1 ) of soybean was recorded by T8 which was closely followed by T7. All the treatments of iron nutrition irrespective of method of application recorded statistically at par grain yield of soybean nonetheless, soil application of FeSO4 was found to be beneficial in correcting the initial deficient iron and zinc status in the soil. In a nutshell, it can be concluded that soil application of FeSO4 @ 10 or 20 kg ha-1 is adequate for obtaining optimum soybean yield and sustaining soil fertility in an iron deficient, slightly calcareous Inceptisol soil.

Profile distribution of trace elements under different land-use systems in North East India

ABSTRACT An investigation was carried out to study the depth-distribution of available trace elements and their relationship with soil physico-chemical properties in soils of Golaghat district, India. Soil samples were collected at 0-20 cm, 20-40 cm, 40-60 cm, 60-80 cm and 80-100 cm depth under five land use systems (LUS) viz. rice, vegetable, sugarcane, bamboo and tea. Particle size distribution data showed significant variation among the diverse LUS and soil depths. Soils were very strongly to medium acidic with a pH range of 4.7 to 5.7 and the highest was recorded at 80–100 cm depth under all the LUS. Soil organic carbon (SOC) content was higher in the surface layer and decreased with increasing soil depths. The highest (13.3 g kg−1) and lowest content of SOC (1.5 g kg−1) in soil were observed under tea and bamboo LUS. Exchangeable cations, cation exchange capacity and base saturation were higher in soils under rice LUS as compared to other LUS. Average DTPA extractable Fe, Mn, Zn and Cu content of the soils ranged from 10.3 to 80.3, 2.0 to 29.2, 0.1 to 0.8 and 0.1 to 1.8 mg kg−1 under diverse LUS.

Effect of Cattle Urine Application on Soil Properties of Lateritic Soils under Spinach Cultivation

The experiment was undertaken to study effect of soil application of cattle urine on growth and yield of spinach in Lateritic soil at wire house of Division of Soil Science and Agriculture Chemistry RCSM College of Agriculture Kolhapur during rabi- 2020. There are total seven nitrogen substitution treatments through urea and cattle urine. The treatment consist of absolute control, recommended dose of fertilizers (40:40:40 kg ha-1N, P2O5 and K2O), general recommended dose of fertilizers (40:40:40 kg ha-1 N, P2O5 and K2O + FYM @ 10 t ha-1), 75% RDN-urea + 25% N- cattle urine, 50% RDN-urea + 50% N-cattle urine, 25% RDN-urea + 75% N- cattle urine, 100% RDN-cattle urine replicated thrice in complexly randomized design.&#x0D; It could be observed from the data that pH and EC of lateritic soil was increased with the application of cattle urine for nitrogen substation. Significantly higher pH (7.67) and EC (1.01dsm-1) of lateritic soil was reported with the application of 100% RDN through cattle urine at first of spinach (46 DAS). Decreasing trend in soil EC was observed at second ut of spinach in all the treatments under study while non-significant results were obtained for soil reaction (pH) at second cut. Significantly higher (1.40%) and (1.07%) organic carbon in lateritic soil was reported with the application of 100% RDN through cattle urine at first and second cut of spinach. Calcium carbonate content in lateritic soil at both the cuts of spinach were recorded non- significant result due to the application of nitrogen through fertilizer and cattle urine. Significantly higher (253.93 kg ha-1) soil available nitrogen (253.93 and 184.97 kg ha-1), phosphorus (30.72 and 29.10 kg ha-1) and potassium (313.43 and 303.00 kg ha-1) were recorded at first and second cut of spinach with the application of 100% RDN through cattle urine respectively. Significantly higher DTPA Fe (26.55 and 24.30 mg kg-1), Mn (23.39 and 21.70 mg kg-1), Zn (7.09 and 3.84 mg kg-1) and Cu (12.01 and 9.12 mg kg-1) were recorded with the application of 100 % RDN thorough cattle urine. Further it can be seen from the data that DTPA availability of metallic micronutrients were higher in those treatments received cattle urine for either substitution of nitrogen @ 25,50, 75 or 100 percent.

Fertility status in wheat (Triticum aestivum) under long-term nutrient management practices in an Alfisol

Soil samples were collected during 2018 from a long-term field experiment on soybean [Glycine max (L.) Merr.]- wheat (Triticum aestivum L.) system continuing since 1972 at Birsa Agriculture University, Jharkhand. The samples were analysed for available major and micro nutrient and biological properties at IARI, New Delhi. The treatments consisted of control, 100% N, 100% NP, 50% NPK, 100% NPK, 150% NPK, 100% NPK + FYM and 100% NPK + Lime. Highest grain yield of wheat was obtained with 100% NPK + FYM followed by 100% NPK + Lime. Whereas, in soybean, 100% NPK + Lime treatment recorded the highest yield, followed by 100% NPK + FYM. The highest available N (218 kg/ha) was found under 150% NPK, which was statistically similar to 100% NPK + FYM. Moreover, highest Bray-P (169 kg/ha) and available K (161 kg/ha) was observed in 100% NPK + FYM and 150% NPK treatment respectively. The DTPA extractable Fe, Mn, Zn and Cu were recorded in the range of 13.9-41.8 mg/kg, 31.1-60.6 mg/ kg, 0.64-1.94 mg/kg and 0.71-1.28 mg/kg, respectively under different nutrient management practices. Treatment 100% NPK + FYM recorded the maximum contents of available micronutrients. Acid phospho-monoesterase (AMP) activity and microbial pools such as microbial biomass carbon (MBC) and microbial biomass phosphorus (MBP) were also found to be highest in 100% NPK + FYM treatment.

Effect of land-use change along\xa0altitudinal\xa0gradients on soil micronutrients in the mountain ecosystem of Indian (Eastern) Himalaya

Management of soil micronutrients for better crop production needs a sound understanding of their status and causes of variability. This is more relevant for acid soils of the mountain ecosystem of Eastern Himalaya (Northeast India). We assessed the status, and the effect of land uses along altitudinal gradients (14 to 4090 masl) on soil properties and micronutrient concentrations (DTPA extractable Fe, Mn, Cu, and Zn) across the region. Soils varied widely in micronutrient concentrations: Fe from 0.665 to 257.1 mg kg−1 while Mn, Cu, and Zn from traces to 93.4, 17.1, and 34.2 mg kg−1, respectively. On conversion of evergreen forests (EF) to upland agriculture (Shifting—SC and Settled—SA) and plantation (PH), Mn, Cu, and Zn concentrations decreased significantly from 30.5, 1.74, and 2.13 mg kg−1 to 6.44–17.8, 0.68–0.81, and 1.06–1.42 mg kg−1, respectively. Grassland (GL) and lowland paddy (LP) had comparable Fe, Mn, and Cu concentrations (except Zn). Degradation of EF to scrubland (SL) recorded the lowest Mn (5.91 mg kg−1), Cu (0.59 mg kg−1), and Zn (0.68 mg kg−1) concentrations. Fe concentration was however increased in degraded SL (+ 73%) over EF (48.7 mg kg−1). The distribution of micronutrients among the land uses was inconsistent and followed the order: (i) Fe: SL > PH > LP > EF > GL > SC > SA, (ii) Mn: EF > GL > LP > PH > SC > SA > SL; (iii) Cu: EF > GL > LP > SC > SA = PH > SL; and (iv) Zn: GL > EF > LP > SC > SA > PH > SL. Four micronutrients responded differently and followed a non-linear, 6th—order polynomial trend along the altitudinal gradients (< 500 to 4100 masl). Peak concentrations of Fe, Mn, and Cu were recorded at 1001–2000 m while Zn was recorded at > 4000 masl. The variability (54–64%) in soil micronutrients was mainly controlled by three key soil properties: acidity, clay, and organic carbon contents. Thus, altitude-specific land-use management holds significance in the distribution of available soil micronutrients in hilly ecosystems.

Zincated Nanoclay Polymer Composite (ZNCPC): Effect on DTPA-Zn, Olsen-P and Soil Enzymatic Activities in Rice Rhizosphere

ABSTRACT Zinc (Zn) is the most deficient micronutrient globally resulting in malnutrition and requires improved mode of delivery for increased nutrient use efficiency. An innovative fertilizer formulation, Zincated nanoclay polymer composite (ZNCPC), containing a total 6.59% Zn was evaluated in a pot experiment in comparison with ZnSO4 using rice (Oryza Sativa L.) (PRH 10 variety) as a test crop. The ZNCPC was applied in two doses [5.0 mg Zn kg−1 (T1) and 2.5 mg Zn kg−1 (T2)] whereas ZnSO4. 7 H2O was applied at single dose (5.0 mg Zn kg−1) (T3) in Zn deficient soil along with a control (without application of Zn) (T4). Effects of two modes of Zn application were evaluated under maximum tillering (MT) (55 days after transplanting) and panicle initiation stage (PI) (70 days after transplanting) on DTPA Zn, Zn uptake, Olsen-P, P uptake and soil enzymatic activities in rhizosphere and non-rhizosphere soil. Treatment T1 increased DTPA-extractable Zn content in rhizosphere soil to 157% in PI stage in comparison with T3. Stimulation of soil enzymes activity namely, dehydrogenase, acid and alkaline phosphatase was recorded in rhizosphere soil. Our study demonstrates that ZNCPC could potentially to be novel and innovative fertilizer formulation to increase Zn uptake in rice.

STATUS OF CERTAIN MICRONUTRIENTS IN SOME WADIS SOILS OF ABU RUDEIS DISTRICT IN SOUTH SINAI, EGYPT

Fifty one soil samples werecallected from some wadis soil i.e.,(El Sheikh Soliman,Sidri,El-Arishia and Bodra) of AduRudeis district, which is lies between some mountain chains. These soil samples were collected to determined their physical and chemical properties and to assess their total and available contents of Fe, Mn, Zn and Cu in a fairly intanse sampling scheme.The results indicate that the texture class varies from sandy to sandy clay loam, The content of CaCO3, organic matter, soil salinity and pH value varies from 12.4 to 579 gkg-1, 6.7 to 30.2 g Kg-1,0.23 to 8.62 dSm-1 and7.6 to 9.3, respectively. The total Fe, Mn, Zn and Cu ranged from 1020 to 9000,370 to 900, 190 to 500 and 90 to 280 mgkg-1, respectively. Most wadis soils of Abu Rudeis district have their DTPA available Fe, Mn, Zn and Cu higher than the critical leveli.e.,4,1,1 and 0.2 mg kg-1, respectively. The respective correlated coefficients, indicate that available Fe, Mn, Zn and Cu showed significant positively correlated with clay (%), (silt + clay)%, CaCO3 content, pH and ECvalues and O.M content, except availableconent of (Fe and Zn), (Mn), (Zn), (Mn) and (Fe and Zn) that showed significant negatively correlationwith clay (%), CaCO3, pH and O.M values,respectively

Conservation Tillage, Residue Management, and Crop Rotation Effects on Soil Major and Micro-nutrients in Semi-arid Vertisols of India

Due to declining soil quality and increasing climate change, resource conservation technologies are often advocated for the food production system. Conservation agriculture (CA) is one of the technologies that increase soil nutrient status without jeopardizing the soil health and quality. The effects of conservation tillage, residue retention, and cropping systems on soil physical, chemical, and biological properties within the irrigated agricultural system are well established. However, scanty information is available on the combined impact of tillage, residue, and cropping system available on the major and micro-nutrient in the rainfed farming systems. Thus, a field experiment was conducted to measure the short-term effect of CA practices on soil properties and major (N, P, and K) and micro (Fe, Mn, Zn, and Cu)-nutrients in a Vertisol of Central India. The field experiment was laid out in a split-plot design consisting of two tillage systems (TS), conventional tillage (CT) and reduced tillage (RT), as the main plots and six cropping systems (CS) as subplots. A total of 144 soil samples were collected after four crop cycles to assess soil properties and nutrient (major and micro-nutrient) status. Results demonstrated that in the surface soil layer (0–5 cm), the major and micro-nutrient concentrations were higher than subsurface layers, regardless of TS and CS. In the surface soils, soil organic carbon (SOC) varied from 0.58 to 0.60% under CT and from 0.60 to 0.62% under RT. Tillage and cropping systems had a significant effect (p < 0.05) on major available nutrients (N, P, and K) at 0–5-cm depth. The DTPA extractable Fe, Mn, Cu, and Zn concentrations exhibited decreasing trends with increasing depth. At 0–5-cm depth, the DTPA-Fe, Mn, Cu, and Zn under CT varied from 7.56 to 9.58 mg kg−1, 15.04 to 15.91 mg kg−1, 1.37 to 1.80 mg kg−1, and 0.57 to 0.62 mg kg−1 and under RT varied from 8.25 to 11.16 mg kg−1, 15.65 to 17.73 mg kg−1, 1.54 to 1.80 mg kg−1, and 0.59 to 0.67 mg kg−1, respectively. We concluded that RT practices, coupled with crop residue retention, positively affected major and micro-nutrient distribution and availability in this soil. Results highlight the importance of nutrient dynamics under different tillage and cropping systems and thus improve the nutrient recommendation in the semi-arid eco-region of Central India.

Field evaluation of Zincated nanoclay polymer composite (ZNCPC): Impact on DTPA-extractable Zn, sequential Zn fractions and apparent Zn recovery under rice rhizosphere

Zinc (Zn) deficiency is a widespread phenomenon globally. Conventional Zn fertilizers (ZnSO4·7H2O) are reported to have very low use efficiency of applied Zn (1–5%). Hence, technological interventions in increasing Zn efficiency are of utmost importance. Keeping in this background, the present investigation was undertaken with the objectives of evaluating ZNCPC (Zincated nanoclay polymer composites), Nano ZnO and ZnSO4·7H2O on various fractions of soil Zn and agronomic parameters under rice rhizosphere in field experiment for two consecutive growing seasons. Nano Zn carriers (ZNCPC at three doses 100%, 75% and 50%) and nano ZnO were evaluated in comparison with ZnSO4·7H2O in a field experiment under rice (Rajendra Mahsuri) rhizosphere. DTPA Zn was significantly increased under 100% ZNCPC (1.99 mg kg−1). Sequential Zn fractionation revealed that under ZNCPC treatments there was significant increase of water soluble, exchangeable and organically bound Zn, whereas there was significant increase of residual and specifically adsorbed Zn under ZnSO4·7H2O. Grain Zn content was maximum under 100% ZNCPC treatment (40.57 mg kg−1) followed by nano ZnO (34.71 mg kg−1). Maximum AZR (Apparent Zn recovery) was found in case of 100% ZNCPC (26.35%) followed by 75% ZNCPC (21.22%) and nano ZnO (18.73%). ZNCPC was found to be promising Zn formulation for increasing Zn use efficiency. Nano ZnO at foliar spray was also proved to be effective in increasing the grain Zn concentration. However, ZNCPC and nano ZnO need to be evaluated in long-term experiment in various soil types and cropping system for evaluating benefit: cost ratio and wide scale farmers’ adaptability.

Effect of wood vinegar on the nutrient release of Zn and Fe in a sodic soil

The use of ZnSO4 and FeSO4 either alone or in combination with wood vinegar is incubated to 60 days and it was compared in the present investigation with an aim to increase the nutrient release pattern of micronutrients viz, Fe and Zn under sodic soil conditions. An incubation experiment was conducted during 2019 in ADAC & RI, Trichy, Tamil Nadu. The incubation experiment comprised of 12 treatments replicated twice in a completely randomized design. The treatments included recommended dose of FeSO4 and ZnSO4 alone and their combination and their combination with three levels of wood vinegar viz., 50, 100 and 150 ml/l applied as as spot drenching (SD). Incubated soil sample were analysed for DTPA Zn and Fe at different intervals (0, 15, 30 45 and 60 DAI). The results of the investigation revealed significant differences in wood vinegar release of DTPA Zn and Fe among the treatments in comparison with the ZnSO4 and FeSO4 either alone or in combination of ZnSO4 and FeSO4. Among the treatments, During 0th day of incubation (DAI), the treatment T12 receiving the recommended dose of both ZnSO4 and FeSO4 along with wood vinegar (WV) @ 150 ml/l as spot drenching recorded significantly higher value of available Zn content (46.68 mg kg-1). The lowest value was recorded in the treatment T1 (6.72 mg kg-1) which received recommended dose of FeSO4 alone. At 0th day of incubation (DAI), the treatment receiving recommended dose of ZnSO4 alone (T2) recorded the lowest DTPA Fe (7.32mg kg-1) while the highest value(48.28 mg kg-1) was recorded in the treatment receiving recommended dose FeSO₄ @ 50 kg /ha along with WV @150 ml/l (T6). Therefore, incorporation of wood vinegar increased the effectiveness of Fe and Zn in sodic soils. The release of DTPA Zn and Fe attained peak at 15 DAI and declined thereafter up to 60 DAI. The experiment received that the DTPA Zn and Fe which contributes to available Zn and Fe considerably increased under wood vinegar drenching in sodic soil.

Influence of Organic Manures and Micronutrients Fertilization on the Soil Properties and Yield of Sesame (Sesamum indicum L.) in Coastal Saline Soil

The light texture coastal saline soils are well known for the deficiency of both macro and micronutrients especially zinc, boron, iron and manganese, etc. The zinc (Zn) and manganese (Mn) plays an important role in improving the growth, yield and quality of sesame. A field experiment was conducted to find out the influence of organics and micronutrients fertilization on the soil properties and yield of sesame in coastal saline soil. The experiment was carried out in a farmer’s field at Ponnanthittu coastal village, near Chidambaram Taluk, Cuddalore district, Tamil Nadu. The Physico- chemical properties and nutrient status of initial soil were: pH- 8.43, EC- 4.25 dS m-1, organic carbon- 2.30 g kg-1 and DTPA Zn – 0.70 mg kg-1 and Mn- 0.96 mg kg-1, respectively. The treatments included were T1 -Control (Recommended dose of NPK), T2 –125% NPK + Composted coirpith (CCP) @ 12.5 t ha-1, T3 -T2 + ZnSO4 @ 25 kg ha-1 soil application (SA), T4 -T2 + MnSO4 @ 5 kg ha-1 (SA), T5 -T2 + (ZnSO4 + MnSO4) SA, T6 -T2 + ZnSO4 @ 0.5 % foliar application (FA),T7 -T2 + MnSO4 (FA), T8 -T2 + (ZnSO4 + MnSO4 )FA, T9 -T2 + ZnSO4 (SA) + ZnSO4 (FA), T10-T2 + MnSO4 (SA) + MnSO4 (FA) and T11-T2 + (ZnSO4 + MnSO4 ) SA + (ZnSO4 + MnSO4 )FA. The experiment was laid out in a Randomized Block Design (RBD) with three replications, using sesame variety TMV 7. The results of the study indicated that the combined application of 125 per cent NPK + composted coirpith (CCP) @ 12.5 t ha-1 + ZnSO4 @ 25 kg ha-1 + MnSO4 @ 5 kg ha-1 through soil application along with foliar application of ZnSO4 @ 0.5% + MnSO4 twice at 0.5 per cent significantly increased the soil nutrient availability, microbial population, enzyme activity and yield of sesame in coastal sandy soil. This treatment recorded the highest sesame seed yield of 815 kg ha-1 and stalk yield of 1805 kg ha-1 as compared 100% recommended NPK alone 421 and 944 kg ha-1 of seed and stalk yield, respectively.

Effects of crop straw and its derived biochar on the mobility and bioavailability in Cd and Zn in two smelter-contaminated alkaline soils

In this study, comparative investigations on the effects of crop straw and its derived biochars on soil Cd and Zn mobility and availability were conducted. Crop straws (i.e. maize straw, rapeseed straw, and wheat straw) and their derived biochars were incubated with two contaminated alkaline soils (FX and TG soils) at 2.5% (w/w). The changes of soil properties like pH, EC, organic matter content, and dissolved organic matter content were investigated along with metal mobility, speciation distribution, and accumulation in ryegrass (Lolium multiflorum Lam.). Results indicated biochar, especially those were high in pH, enhanced soil pH (>0.2 units, p < 0.05), whereas a continuous reduction of soil pH was observed among treatments with crop straws. Both soil EC and the organic matter content increased with the application of both crop straws and biochars. In term of metals, Cd and Zn mobility were reduced with 6–14%/1–5% and 6–27%/7–15% reduction in the DTPA extractable Cd and Zn contents in TG and FX soil treatments, respectively. Moreover, distinct changes of metals in different fractions were also observed (acid soluble and reducible fraction → oxidizable fraction in straw treatments; acid soluble fraction → reducible soluble fraction in biochar amendments). Furthermore, the biological analysis revealed that the growth of ryegrass was promoted, but the accumulation of metals in ryegrass shoots was reduced, especially in MS700 treatment. Apart from the amendments, metal immobilization efficiencies were negatively correlated with the contamination status. Despite that, a higher rate of biochar application (>10%) could dramatically reduce the amount of available metal in soil extracts, except for Zn in FX soil treatments. This present work demonstrated that biochars, especially those produced at a higher temperature, are superior to crop straws to immobilize metals in soils. However, the remediation efficiencies were strongly restricted by soil pH and contamination status.

Physico-Chemical Properties of Soil and Mineral Composition of Plants as Affected by Fox Nut-Based Cropping Systems

Fox nut (Euryale ferox Salisb.) is exclusively an aquatic crop and generally grown naturally in non-saline wetland areas having stagnant water. Prolonged submergence in lowlands impedes the cultivation of most field crops except few one such as rice. For enhancing the system productivity, crop diversification technology needs to be adopted in wetland/aquatic ecosystems as well. In present study fox nut-based eight different crop rotations, viz. fox nut-fox nut, fox nut-rice, fox nut-wheat, fox nut-berseem, fox nut-water chestnut, fox nut-rice-wheat, fox nut-rice-berseem and fox nut-water chestnut-berseem were followed consecutively for three years (2012-13 to 2015-16). The pooled data showed that fox nut-water chestnut-berseem cropping system had more organic carbon, available N, P and K to the tune of 25 %, 14.75 %, 26.66 % and 6.80 %, respectively over the fox nut-fox nut cropping system. The soils under fox nut-rice-berseem cropping system had the highest concentration of DTPA Cu (1.82 mg kg-1) and Zn (0.35 mg kg-1). Fox nut and water chestnut retained the highest tissue concentrations of the less soluble Fe and Mn and P, Cu and Zn. The results indicated that adoption of fox nut-water chestnut-berseem cropping system significantly improved the fertility status of soil in the aquatic low land ecosystem.