Time filter

Source Type

Coimbatore, India

Tamil Nadu Agricultural University is an agricultural university located in Coimbatore, Tamil Nadu, India. Wikipedia.

Maski D.,Iowa State University | Durairaj D.,Tamil Nadu Agricultural University
Crop Protection | Year: 2010

Wastage of agricultural chemicals and ensuing environmental pollution is an issue, where ineffective spray deposition is a major concern with conventional pesticide application methods. Electrostatic spraying is known to be one of the most effective methods to improve leaf abaxial (underside) surface deposition, overall deposition, and distribution on the plant targets. Deposition of charged sprays on leaf abaxial and adaxial (upper) surfaces as influenced by the spray charging voltage (system), application speed (operational), target height and orientation (target) parameters was studied in the laboratory. An air-assisted electrostatic induction spray charging system attached to a moving carriage was used to apply charged spray at uniform application (ground) speeds. Spray deposition (101-71 μm NMD), determined using a fluorescent tracer technique increased with charging (0-5.5 mC kg-1) on leaf abaxial and decreased with charging on adaxial surface. The deposition was higher on abaxial (0.66-1.33 μg cm-2) at 30° below (horizontal plane) and on adaxial (0.78-1.79 μg cm-2) at 0° (horizontal) target orientation for lower (0.278 m s-1) application speed. At all target heights, abaxial deposition increased with charging voltage (0-4.0 kV) for medium application speed (0.417 m s-1) and adaxial deposition decreased with charging voltage for lower application speed (0.278 m s-1). The medium application speed with higher charging voltage was optimum for abaxial and adaxial deposition. The droplet velocity and charging voltage were the key factors for obtaining desired spray deposition on targets. All the selected factors including target orientation (O), application speed (S), target surface (L), and charging voltage (V), and their interactions except between O and S were significant at lower (0.35 m) and medium (0.65 m) target heights. All the factors and their interactions except between O and V were significant at higher (0.95 m) height. Electrostatically charged spray improved the underside (abaxial) and overall deposition. The deposition was substantially influenced by factors such as charging voltage, application speed, plant target height, and target orientation. © 2009 Elsevier Ltd. All rights reserved. Source

Sherene T.,Tamil Nadu Agricultural University
Research Journal of Chemistry and Environment | Year: 2012

A survey work was undertaken to assess the concentration of heavy metal pollution in soils of Coimbatore district. Totally three hundred and eight surface (0-15 cm) soil samples were collected around the industrial areas by using auger. Among the different industrial areas, electro plating and sewage water irrigated areas fell in excess tolerable category for Pb and Ni. As per SPI scale, the soils collected in the vicinity of electro plating, textile, casting and sewage water irrigated fields seemed to be dangerously polluted with toxic Pb, Ni, Cd, Cr, Cu and Zn. The delineation of Pb and Ni contaminated sites of Coimbatore district was done using SURFER software package. Therefore, there is a possibility of silent epidemic of environmental metal poisoning from the ever-increasing amount of metals wasted into biosphere. Source

Maski D.,Iowa State University | Durairaj D.,Tamil Nadu Agricultural University
Journal of Electrostatics | Year: 2010

Combinations of electrode voltage, liquid flow rate, and properties can enhance chargeability of electrostatic sprays for effective pesticide application, though the combined effects of these parameters are not well understood. Generally, 4 kV voltage and lower (30, 45, and 60 mL min-1) flow rate of tank water produced greater chargeability compared to ground water sprays. The rate of increase in spray chargeability with decreased liquid flow rate was higher in the lower flow rates. The outcome of the study will be helpful for the more targeted and environmentally safe application of pesticide sprays and development of suitable electrostatic spraying systems. Source

Kasirajan S.,Tamil Nadu Agricultural University | Ngouajio M.,Michigan State University
Agronomy for Sustainable Development | Year: 2012

The use of plastic mulch in agriculture has increased dramatically in the last 10 years throughout the world. This increase is due to benefits such as increase in soil temperature, reduced weed pressure, moisture conservation, reduction of certain insect pests, higher crop yields, and more efficient use of soil nutrients. However, disposing of used plastic films, which cause pollution, has led to development of photodegradable and biodegradable mulches. Here we review the use of plastic mulches in agriculture, with special reference to biodegradable mulches. Major topics discussed are (1) history of plastic mulch and impact on crop yield and pest management, (2) limitations of polyethylene mulches and potential alternatives, (3) biodegradable and photodegradable plastic mulches, (4) field performance of biodegradable mulches, and (5) use of biodegradable plastic mulches in organic production. We found that (1) despite multiple benefits, removal and disposal of conventional polyethylene mulches remains a major agronomic, economic, and environmental constraint; (2) early use of photodegradable plastic mulch during the 1970s and 1980s, wrongly named biodegradable mulch films, discouraged adoption of new biodegradable mulch films because they were too expensive and their breakdown was unpredictable; (3) biodegradable plastic films are converted through microbial activity in the soil to carbon dioxide, water, and natural substances; (4) polymers such as poly(lactic acid), poly(butylene adipatecoterephthalate), poly(?-caprolactone), and starch-based polymer blends or copolymers can degrade when exposed to bioactive environments such as soil and compost; (5)with truly biodegradable materials obtained from petroleum and natural resources, opportunity for using biodegradable polymers as agricultural mulch films has become more viable; and (6) the source of polymer and additives may limit use of some biodegradable mulches in organic production. More knowledge is needed on the effect of biodegradable mulches on crop growth, microclimate modifications, soil biota, soil fertility, and yields. © The Author(s) 2012. Source

The biocidal activity of various isothiocyanates (ITCs) released by Brassica tissues is well-known for its potential to suppress a range of soil-borne pests and diseases. A study was carried out to evaluate the effect of incorporating fresh crucifer residue on root knot nematode, Meloidogyne hapla inoculum density, root knot disease development and celery yield. The ethanol extracts of cabbage, cauliflower, radish and Chinese cabbage leaves after harvest was applied to moist soil with high nematode population and covered with low density polyethylene sheets (50 micron thickness). After 15 days the sheet was removed and celery seedlings were planted. Observation on shoot length, root length, green leaf and stalk yield and nematode population were recorded. Biofumigation with sulphur containing cruciferous vegetable waste at the rate of 1kg/5 kg soil was found to reduce significantly the root knot nematode, M.hapla infecting celery and enhance plant growth and yield. Among the various sources evaluated radish leaf residue was the most effective resulting in 60.6 % reduction in nematode population in soil and 41.9% increase in celery green leaf and stalk yield compared to untreated control. © JBiopest. Source

Discover hidden collaborations