Automatic adjustment of harrowing intensity in cereals using digital image analysis

Precision farming technologies were implemented into a commercial harrow to increase selectivity of weed harrowing in spring cereals. Digital cameras were mounted before and after the harrow measuring crop cover. Crop soil cover (CSC) was computed out of these two images. Eight field experiments were carried out in spring cereals. Mode of harrowing intensity was changed in four experiments by speed, number of passes and tine angle. Each mode was varied in five intensities. In four experiments, only intensity of harrowing was changed. Weed control efficacy (WCE) and CSC were measured immediately after harrowing. Crop recovery was assessed 14 days after harrowing. Modes of intensity were not significantly different. However, intensity had significant effects on WCE and CSC. Cereals recovered from 10% CSC, and selectivity was in the constant range at 10% CSC. Therefore, 10% CSC was the threshold for the decision algorithm. If the actual CSC was below 10% CSC, intensity was increased. If the actual CSC was higher than 10%, intensity was decreased. Image analysis, decision support system and automatic control of harrowing intensity by hydraulic adjustment of tine angle were installed on a controller mounted on the harrow. The new system was tested in an additional field study. Threshold values for CSC were set at 10%, 30% and 60%. Automatic tine angle adjustment precisely realised the three different CSC values with variations of 1.5% to 3%. This development contributes to selective weed control and supports farmers during harrowing.     

Correlation Study between Land Use, Water Quality, and Heavy Metals (Cd, Pb, and Zn) Content in Water and Green Lipped Mussels Perna viridis (Linnaeus.) at the Johor Strait

In order to observe the variation in land use changes, satellite images from the Landsat Thematic Mapper (TM) and the Enhanced Thematic Mapper (ETM) for 1991, 2000, 2005, and 2008 were used to compare the differences between selected water quality parameters, including heavy metal (Cd, Pb, and Zn) content in both water and green mussels or Perna viridis (Linnaeus.) before and after the increase in land use activities beginning from 2006. The samples were collected at 11 points for water and 4 points for green mussels between the Second Link and the Causeway Link at the Johor Strait in 2009 and were analyzed for pH, temperature degrees Celsius), dissolved oxygen, ammoniacal nitrogen, and heavy metal (Cd, Pb, and Zn) content.     

Substituting urea by organic wastes for improving maize yield in alkaline soil

Abstract

Nitrogen (N) deficiency is a very common problem of alkaline soils. Incorporation of organic residues with urea could be promising practice for improving soil properties and crop yield. This study was aimed, to evaluate the responses of two maize cultivar (Azam and Jalal) to organic wastes and Urea (sole organic residues i.e. seed cake (SC), poultry manure (PM), press mud (PrM) and mineral nitrogen (urea) and their combinations with urea (25%, 50% or 75%) applied at 150?kg N ha^?1 under field conditions. Significant differences were recorded for leaf area index, plant height, number of grains ear^?1, 1000 grain weight, biological and grain yield to N sources. Maize cultivar Jalal performed significantly better than Azam for all tested traits. The performance of both cultivars was significantly better when N was applied as either SC/PM with urea at 25:75, SC and PM with urea at 25:25:50, 100% sole urea, SC/PrM with urea at 50:50, or all organic N sources (25%) with urea (75%). Integration of organic wastes with urea gave the higher maize yield however, it was similar to the yield obtained from sole urea but due to allied environmental and health hazards, the sole use of urea could not be encouraged.     

Impact of urea and farm yard manure on nitrate concentration in soil profile and productivity of wheat crop

Abstract

During the last century, concerns about nitrate presence in the groundwater have tremendously increased worldwide, mainly because of its detrimental consequences on environment and human health. There are different factors contributing their past in nitrate pollution, farm manure is given due consideration. Knowing above facts, a field study was performed to check the effect of different farm yard manure (FYM) levels with urea on nitrate distribution in the soil profile and yield of wheat crop. The experiment was set out in a randomized complete block design, consisted of application of nitrogen at 125?kg ha^?1 from urea, 80?kg ha^?1 of N from urea +10 tons FYM ha^?1 and 20 tons FYM ha^?1 with three replications. Wheat (cultivar S7ehar-2006) was sown as test crop. Soil samples were examined to measure the nitrate concentration from four different depths (0–25, 25–50, 50–75, and 75–100?cm) after harvesting. Results showed that the straw yield, total biomass, spike length, and number of grains per spike and 1000-grain weight were significantly influenced by fertilizer strategies. All manure treatments significantly affected the infiltration rate and concentration of nitrate at different depths of the soil profile. Farm yard manure showed greater nitrate concentration up to 50?cm depth as compared to alone urea and combined application, while at the depth of 100?cm, combined application of urea and FYM showed a minimum concentration of nitrates than alone application of either urea or FYM.     

Silicon biostimulant enhances the growth characteristics and fortifies the bioactive compounds in common and Tartary buckwheat plant

Journal of Crop Science and Biotechnology - Silicon is a potential biostimulant that has been used to enhance the yield and quality of plant products. Therefore, we aimed to evaluate the effect of...     

Kinetics and Energetics of Azo Dye Decolorization by Pycnoporus sanguineus

Trypan Blue, an azo dye, was decolorized using the self-immobilizing fungal biomass of Pycnoporus sanguineus. The extent and the rate of dye decolorization were directly proportional to the initial dye concentration (20–60 mg L^?1) and the reaction temperature (25–45°C). Mass transfer within and outside the pellets did not limit dye degradation. The apparent kinetics of the decolorization reaction followed a first-order behavior. Activation energy for the biological decolorization was calculated at 23 kJ mol^?1. The decolorization process was endothermic with the enthalpy and entropy values calculated at 45.6 kJ mol^?1 and 146 J mol^?1 K^?1, respectively. Based on the value of Gibbs free energy change, the decolorization reaction under the conditions studied was non-spontaneous below 39°C but was spontaneous at higher temperatures.     

Influence of Molecular Weight and Degree of Deacetylation of Low Molecular Weight Chitosan on the Bioactivity of Oral Insulin Preparations

The objective of the present study was to prepare and characterize low molecular weight chitosan (LMWC) with different molecular weight and degrees of deacetylation (DDA) and to optimize their use in oral insulin nano delivery systems. Water in oil nanosized systems containing LMWC-insulin polyelectrolyte complexes were constructed and their ability to reduce blood glucose was assessed in vivo on diabetic rats. Upon acid depolymerization and testing by viscosity method, three molecular weights of LMWC namely, 1.3, 13 and 18 kDa were obtained. As for the DDA, three LMWCs of 55%, 80% and 100% DDA were prepared and characterized by spectroscopic methods for each molecular weight. The obtained LMWCs showed different morphological and in silico patterns. Following complexation of LMWCs with insulin, different aggregation sizes were obtained. Moreover, the in vivo tested formulations showed different activities of blood glucose reduction. The highest glucose reduction was achieved with 1.3 kDa LMWC of 55% DDA. The current study emphasizes the importance of optimizing the molecular weight along with the DDA of the incorporated LMWC in oral insulin delivery preparations in order to ensure the highest performance of such delivery systems.     

Low Molecular Weight Chitosan–Insulin Polyelectrolyte Complex: Characterization and Stability Studies

The aim of the work reported herein was to investigate the effect of various low molecular weight chitosans (LMWCs) on the stability of insulin using USP HPLC methods. Insulin was found to be stable in a polyelectrolyte complex (PEC) consisting of insulin and LMWC in the presence of a Tris-buffer at pH 6.5. In the presence of LMWC, the stability of insulin increased with decreasing molecular weight of LMWC; 13 kDa LMWC was the most efficient molecular weight for enhancing the physical and chemical stability of insulin. Solubilization of insulin-LMWC polyelectrolyte complex (I-LMWC PEC) in a reverse micelle (RM) system, administered to diabetic rats, results in an oral delivery system for insulin with acceptable bioactivity.