Alleviation of Multinutrient Deficiency for Productivity Enhancement of Rain-Fed Soybean and Finger Millet in the Semi-arid Region of India

Soil nutrient contents were determined in 802 surface soil samples (0–15 cm deep) collected from farmers' fields that support extensive cultivation of soybean (Glycine max L.) and finger millet (Eleusine coracana G.), spread across three districts, in the semi-arid regions of Karnataka, India. Following soil analysis, on-farm crop trials were conducted during 2005–2007 to study the crop response to the soil application of nitrogen (N), phosphorus (P), sulfur (S), boron (B), and zinc (Zn) fertilizers. Analyses of soil samples revealed that 4–83% fields were deficient in N, 34–65% in P, 83–93% in extractable S, 53–96% in B, and 34–88% of farmers' fields were deficient in Zn. On-farm trials conducted during the three rainy seasons (2005, 2006, and 2007) significantly (P ≤ 0.05) enhanced crop productivity indices such as yields of grain, stover, and total biomass in soybean and finger millet crops. Integrated management of deficient nutrients in finger millet and soybean crops significantly enhanced the grain and straw uptake of N, P, K, S, and Zn

Nutrient balances - a guide to improving sorghum- and groundnut-based dryland cropping systems in semi-arid tropical India

Information on soil-plant nutrient balance in India and elsewhere is scarce and mostly generalized. A review of earlier studies on nutrient balances was done to assess their relevance for researchers, policy makers, and farmers' understanding, to manage soil fertility for sustainable crop productivity. An on-farm nutrient balance study during 1995/1996 and 1996/1997 was designed to understand nutrient balances resulting from farmers' practices in semi-arid tropical regions of India. The soil in this area is an Alfisol. This diagnostic study targeted sorghum-based cropping systems and groundnut-based cropping systems in low rainfall areas of the Indian SAT. Selection of farmers for this study was done through a systematic survey and analyses of factors effecting farmers' decision making for nutrient inputs. Intensive plot-specific nutrient input and output measurements were carried out on 53 farmers' fields for sorghum-based systems and 45 farmers' fields for groundnut-based system in this study. Topsoil mineral nitrogen (N) content observed in 2 years at the beginning of the crop season in two locations of Andhra Pradesh, India, was surprisingly high and exchangeable potassium (K) contents also indicated sufficient supply in most fields. Available phosphorus (P) in the majority of fields in both locations was around threshold levels, and just sufficient for most crops. The nutrient balance in sorghum-based systems indicates a moderate to higher negative balance of potassium leading to soil mining for potassium supply in these systems. Nitrogen and P balances were generally positive. Although the groundnut-based system accumulated 53% of its N requirements through biological nitrogen fixation (BNF), negative balances of N and K were observed mainly due to low applications of these nutrients. Application of K along with options for improving BNF of groundnut are suggested. Better nodulating groundnut cultivars and efficient rhizobium strains need to be introduced. High positive balances were observed in the systems whenever commercial crops like castor and cotton were sown in the rotation. This indicates farmers' preferences for applying excess quantities of farmyard manure to commercially important crops even in dryland farming systems. The replenishment costs of mined nutrients annually in different cropping systems were calculated based on current market prices of inorganic fertilizers

Soil test-based nutrient balancing improved crop productivity and rural livelihoods: case study from rainfed semi-arid tropics in Andhra Pradesh, India

Widespread multinutrient deficiencies in the semi-arid tropics (SAT) are among major factors for large gaps between farmers’ current crop yields and potential yields. In this study, we adopted a stratified soil sampling method to assess soil fertility-related constraints in farmers’ fields in eight districts of Andhra Pradesh in the semi-arid tropics of India. Most of the fields across all eight districts were critical in sulfur (61%–98% deficient fields); and up to six districts each in boron (83%–98% deficient fields), zinc (50–85% deficient fields), and soil organic carbon (55–97% deficient fields). Low soil organic carbon specifically indicates nitrogen deficiency. Phosphorus deficiency was critical in three districts (60–84%) while potassium in general was adequate. Soil test-based nutrient balancing through the application of sulfur, boron, and zinc in addition to farmers’ practice of adding only nitrogen, phosphorus, and potassium increased crop productivity by 8%–102%. Benefit–cost ratio (1.60–28.5) proved favourable to scale-up balanced nutrition. Better post-harvest soil health and residual benefits of sulfur, boron, and zinc up to four succeeding seasons indicated sustainability of the practice. Results showed that balanced nutrition is a way forward for sustainably improving farm productivity and livelihoods

Productivity enhancement and improved livelihoods through participatory soil fertility management in Tribal Districts of Andhra Pradesh

Under the National Agricultural Innovation Project (NAIP) , three tribal-dominated districts (Adilabad, Khammam and Nalgonda) in Andhra Pradesh were selected to study the role of Site Specific Nutrient Management (SSNM) and balanced nutrition to enhancing income and livelihood security. By adopting a toposequence approach, 720 surface soil samples were collected from 39 villages with the participation of farmers. The soil sampling was based on stratified random sampling. Generally, it is believed that soils in the tribal region are rich in organic carbon and high in soil fertility because of relatively low intensity cropping. Contrary to this belief, the results of soil analyses showed that most of the soils are low to medium in organic carbon, low in available N and P, and low to high in available K. Among the secondary and micronutrients, S, B and Zn are the emerging nutritional constraints. By adopting SSNMand balanced nutrition approach, increase in yield ranged from 13 to 53% in cotton, 15 to 58% in chickpea, 18 to 44% in groundnut, 33 to 47% in green gram; and in vegetable crops, the increase in yield varied from 25 to 54% in tomato and 7-10% in Bhindi (Ladies fmger) over the farmer's practice (FP). Net income and return per Re investment also increased by balanced nutrition. In cotton, net income obtained ranged between Rs. 30783 and 55533 ha-1 in Adilabad, Rs. 15,030 and 70,533 ha-1 in Khammam under balanced nutrient management. In other crops, the net return was Rs. 5564-14214 ha-! in chickpea, . Rs. 8380-13840 ha-1 in groundnut, Rs. 4207-8995 ha'! in green gram, Rs. 47526-78329 ha-! in tomato and Rs. 15570-38370 ha-1 in Bhindi under balanced nutrition. Mean value of return per Re investment was 2.97-3.05, 1.78, 1.60, 1.55,2.09 Ind 1.78 in cotton, chickpea, groundnut, green gram, tomato and Bhindi, respectively under balanced nutrition

Contribution of Nutrients through Critical Irrigation from Diverse Water Sources in Selected Watersheds of Semi-arid Tropical India

Critical irrigation is one of the most important management options to protect the crop during weather aberrations like dry spells at critical stages of the crop growth in semi arid condition. Various water harvesting structures are useful in watershed areas to cope up with mid-season droughts. These structures provide critical irrigations at sensitive crop growth stages by which they supply essential nutrients to some extent. We estimated the contribution of various sources of water in terms of plant nutrients and to what extent critical irrigations meet nutrient requirements of various crops. By giving 4 cm irrigation, the maximum major nutrient (kg ha-1) addition in the studied watersheds is of the following order NO3 (5.2, Kothapalli); SO4 (15.2, Kolar); Na (72.0, Haveri); K (3.6, Govardhanapura); Ca (38.5, Semli and Shyamapura); Mg (20.5, Kothapalli) and for micronutrients (g ha-1) Fe (109, Kolar); Zn (40, Kothapalli); Mn (90, Kolar); Cu (120, ICRISAT) and B (190, ICRISAT). Percentage of recommended dose of nutrients which can be met by three irrigations in cereal crops (5- 10, 15-100, 10-20% in N,S,K respectively); legumes (5-30,10-100, 5-10% of N,S,K respectively); cotton (10-15, 25-30, 5-10% of N,S,K, respectively) and micronutrients such as Fe, Zn, Mn, Cu and B to the full extent. With the number of critical irrigations increased, application of secondary and micro nutrients should be avoided which otherwise leads to higher cost of alleviation and environmental pollution

Spectral matching techniques (SMTs) and automated cropland classification algorithms (ACCAs) for mapping croplands of Australia using MODIS 250-m time-series (2000–2015) data

Mapping croplands, including fallow areas, are an important measure to determine the quantity of food that is produced, where they are produced, and when they are produced (e.g. seasonality). Furthermore, croplands are known as water guzzlers by consuming anywhere between 70% and 90% of all human water use globally. Given these facts and the increase in global population to nearly 10 billion by the year 2050, the need for routine, rapid, and automated cropland mapping year-after-year and/or season-after-season is of great importance. The overarching goal of this study was to generate standard and routine cropland products, year-after-year, over very large areas through the use of two novel methods: (a) quantitative spectral matching techniques (QSMTs) applied at continental level and (b) rule-based Automated Cropland Classification Algorithm (ACCA) with the ability to hind-cast, now-cast, and future-cast. Australia was chosen for the study given its extensive croplands, rich history of agriculture, and yet nonexistent routine yearly generated cropland products using multi-temporal remote sensing. This research produced three distinct cropland products using Moderate Resolution Imaging Spectroradiometer (MODIS) 250-m normalized difference vegetation index 16-day composite time-series data for 16 years: 2000 through 2015. The products consisted of: (1) cropland extent/areas versus cropland fallow areas, (2) irrigated versus rainfed croplands, and (3) cropping intensities: single, double, and continuous cropping. An accurate reference cropland product (RCP) for the year 2014 (RCP2014) produced using QSMT was used as a knowledge base to train and develop the ACCA algorithm that was then applied to the MODIS time-series data for the years 2000–2015. A comparison between the ACCA-derived cropland products (ACPs) for the year 2014 (ACP2014) versus RCP2014 provided an overall agreement of 89.4% (kappa = 0.814) with six classes: (a) producer’s accuracies varying between 72% and 90% and (b) user’s accuracies varying between 79% and 90%. ACPs for the individual years 2000–2013 and 2015 (ACP2000–ACP2013, ACP2015) showed very strong similarities with several other studies. The extent and vigor of the Australian croplands versus cropland fallows were accurately captured by the ACCA algorithm for the years 2000–2015, thus highlighting the value of the study in food security analysis. The ACCA algorithm and the cropland products are released through http://croplands.org/app/map and http://geography.wr.usgs.gov/science/croplands/algorithms/australia_250m.htm

Kinetics and mechanism of oxidation of thiosemicarbazones by acid bromate

175-181The kinetics of oxidation of benzaldehyde, propanaldehyde, acetone and acetophenone thiosemicarbazones by acid bromate have been studied in aqueous acetic acid medium (1:1, v/v). The rates show first order dependence on [oxidant) in all the cases, but show varying orders in [H+] depending upon [H+], In the [H+] range 0.001-0.02 mol dm-3 the reaction order is fractional in [H+]and it is > 1 in the [H+] range > 0.02 mol dm-3. The reactions show fractional order in [hydrazone], in both the ranges of [HCIO4]. Addition of KBr has little effect on the rates of oxidations. Suitable mechanisms consistent with the observed results have been suggested and the related rate laws deduced. Coefficients of the rate limiting steps have been calculated at different temperatures and the activation parameters are computed. The validity of rate laws is also tested by recalculating the rate constants from the deduced rate laws as [hydrazone] and [H+] are varied. Reasonably good agreement between the recalculated values and the experimental constants provides support to the proposed mechanisms