The profitability of variable rate lime in wheat

Grid sampling allows a variable rate of lime to be applied and has been marketed as a cost saver to producers. However, there is little research that shows if this precision application is profitable or not. Previous research on variable-rate lime has considered only a small number of fields. This paper uses soil sampling data from 111 fields provided by producers in Oklahoma and Kansas. The 5-year average net present values are compared between variable-rate and uniform-rate lime for grain-only wheat production, dual-purpose wheat grain and forage production, and a wheat–soybean rotation. Sensitivity analysis was done for varying grain prices as well as grain yield potential. When using historical average yields and recent prices for Oklahoma, variable rate was not profitable on average for these 111 fields for either a grain-only, dual-purpose, or wheat–soybean production. However, when yield or prices were above average, variable rate was profitable. Thus, variable rate liming can be profitable for these fields, but it requires either above average yields, a high value crop, or above average prices.

     

Delineating site-specific management zones on pasture soil using a probabilistic and objective model and geostatistical techniques

Precision Agriculture - In recent years, different algorithms have been utilised to delineate management zones, areas with similar properties, within agricultural fields. However, there are few...     

Golf course superintendents’ knowledge of variability within fairways: a tool for precision turfgrass management

Precision Agriculture - Golf course superintendent’s knowledge of variability may be an overlooked and underutilized tool for precision turfgrass management (PTM). This case study used a...     

Effect of melatonin on visceral fat deposition,lipid metabolism and hepatic lipo-metabolic gene expression in male rats

Melatonin (MT) influences lipid metabolism in animals; however, the mechanistic effect of melatonin on liver fat and abdominal adipose deposition requires further clarity. In order to study the effects of melatonin on lipid metabolism, and hepatic fat and abdominal adipose deposition in animals, twenty Sprague–Dawley (SD) rats of 6 weeks of age with similar bodyweight were randomly divided into two groups: control (CTL) and MT-treated (10 mg/kg/day). During a 60-day experiment, food intake and bodyweight were measured daily and weekly respectively. At the end of treatment, blood samples were collected to collect plasma to quantify hormones and metabolic indicators of lipid metabolism. In addition, organ and abdominal adipose depots including liver, and omental, perirenal, and epididymal fat were weighed. Liver tissue was sampled for sectioning, long-chain fatty acid (LCFA) quantification, and gene chip and Real-time quantitative PCR (qPCR) analyses. The results showed that liver weight and index (ratio of liver weight to body weight) in MT group reduced by 20.69% and 9.63% respectively; omentum weight and index reduced by 59.88% and 54.93% respectively, and epididymal fat weight reduced by 45.34% (p = 0.049), relative to CTL. Plasma lipid indices, triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and total cholesterol (TC) with MT treatment decreased significantly compared with the control. Fat and 8 LCFA content in liver in MT group also decreased. Gene chip and qPCR demonstrated that there were 289 genes up-regulated and 293 genes down-regulated by MT. Further analysis found that the mRNA expression of lipolysis-related genes increased, while the mRNA expression of lipogenesis-related enzymes decreased (p < 0.05) with MT. This study concluded that melatonin greatly affected fat deposition, and hepatic LCFA supply and the expression of genes associated with lipogenesis and lipolysis.     

Possibility of Reducing Soil Allelotoxicity for Grain Crops

Eurasian Soil Science - The results of experiments on possible reduction of soil allelotoxicity level for grain crops are presented. It was found that autoclaving of soils significantly reduces...     

Assessing the Complexing Properties of Soil Organic Matter by IMAC (Case Study of Copper Ions)

Eurasian Soil Science - Immobilized metal affinity chromatography (IMAC) has been used to fractionate organic compounds in alkaline extracts from forest soils of the Komi Republic by their ability...     

Multidirectional Changes in Temperature of Permafrost-Affected Soils during the Growing Season against the Background Increase in the Mean Annual Air Temperature

Eurasian Soil Science - Data on air and soil temperatures at the Verkhoyansk and Oymyakon weather stations in the East Siberian permafrost-taiga region are analyzed. The soils are represented by...     

Application of Geoelectric Methods for Mapping Soil Heterogeneity

Eurasian Soil Science - Application of a set of electrical methods used in geophysics—direct current resistance and induced polarization—for the purposes of mapping soil heterogeneity...