Time filter

Source Type

Bhattacharyya R.,University of Wolverhampton | Bhattacharyya R.,Vivekananda Institute of Hill Agriculture | Smets T.,Catholic University of Leuven | Fullen M.A.,University of Wolverhampton | And 2 more authors.
Catena | Year: 2010

Despite geotextiles having potential for soil conservation, limited scientific data are available to assess the effects of geotextiles in reducing runoff and water erosion. Hence, the objective of this review is to analyse the effects of plot length (L) and other possible affecting factors [cover percentage (C, %), slope gradient (S), rainfall duration (D), rainfall intensity (I), sand, silt and clay contents, soil organic matter (SOM) content and geotextile type (natural or synthetic)] on the effectiveness of geotextiles in reducing soil and water loss, based on reported experimental data. From linear regressions, C (%) and soil sand, silt and clay contents are found to be the most important variables in reducing SLR (ratio of soil loss in bare plots to that in geotextile treated plots) for splash, C (%) for interrill and D (min) for rill and interrill erosion processes, respectively. Soil clay and silt contents and D are key variables in decreasing RR (ratio of runoff from bare plots to that from geotextile treated plots) for interrill, and clay content for rill and interrill erosion processes, respectively. The linear relationship between mean b-value (geotextile effectiveness factor in reducing soil loss) and L of all studies was not significant (P>0.05). The same is true for the relationship between L and SLR, and L and RR. However, when L is added to an equation as an interaction term with C (%), geotextile cover is significantly (P<0.05) more effective in reducing SLR on shorter plots than longer ones for both interrill and rill and interrill erosion processes. Buffer strip plots (area coverage ~10%) with Borassus and Buriti mats have the highest b-values. © 2010 Elsevier B.V.

Preetha G.,Tamil Nadu Agricultural University | Manoharan T.,Tamil Nadu Agricultural University | Stanley J.,Vivekananda Institute of Hill Agriculture | Kuttalam S.,Tamil Nadu Agricultural University
Journal of Plant Protection Research | Year: 2010

Laboratory studies were carried out to compare the toxicity of the chloronicotinyl insecticide, imidacloprid on parasitoids. The studies took place at the Tamil Nadu Agricultural University, Coimbatore from 2006-2007. Imidacloprid was tested against three beneficial insects viz., an egg parasitoid, egg larval parasitoid and a larval parasitoid representing two families of Hymenoptera: Trichogrammatidae (Trichogramma chilonis Ishii) and Braconidae (Chelonus blackburni Cameron; Bracon hebetor Say) that attack insect pests of cotton. The toxicity of imidacloprid was evaluated by treating the parasitized eggs using an atomizer in the case of T. chilonis and glass scintillation vial residue bioassay method for the adults of C. blackburni and B. hebetor. The toxicity of imidacloprid to parasitoids was compared with another neonicotinoid, named thiamethoxam, and a standard check, methyl demeton. Imidacloprid 17.8 SL did not cause any adverse effects on the adult emergence and parasitization of T. chilonis. At the recommended dose of imidacloprid [25 g active substance (a.s.)/ha], 90.67 and 85.32 per cent adult emergence and parasitization was recorded, respectively. The recommended dose of imidacloprid caused 56 per cent mortality and was found to have moderate impact on the adults of C. blackburni. On the other hand, it was found to be toxic to the parasitoid B. hebetor, causing 70 per cent mortality at 48 hours after treatment (HAT). The data presented here will provide pest managers with specific information on the compatibility of selected insecticides with natural enemies attacking pests of cotton, Gossypium hirsutum L.

Mangaraj S.,Central Institute of Agricultural Engineering | Singh K.P.,Vivekananda Institute of Hill Agriculture
Food and Bioprocess Technology | Year: 2011

Optimization of machine parameters using response surface methodology (RSM) greatly overcomes the numbers of experimental trials generally undertaken for milling study of pigeon pea apart from maximizing the output of the system. The independent milling parameters for Central Institute of Agricultural Engineering dal mill viz., roller speed, emery grit size, and feed rates were optimized for pigeon pea dehulling using RSM. The roller peripheral speed of 9.6 m/s, emery grit size 1 mm, and feed rate 111 kg/h were found optimal. The dal recovery and milling efficiency at optimized independent parameters were 75% and 80%, respectively. © 2009 Springer Science + Business Media, LLC.

Stanley J.,Vivekananda Institute of Hill Agriculture | Manoharan T.,Tamil Nadu Agricultural University | Kuttalam S.,Tamil Nadu Agricultural University
Archives of Phytopathology and Plant Protection | Year: 2014

The populations of cotton leafhopper, Amrasca biguttula biguttula were collected from two different locations, viz. Coimbatore and Salem, and the identified susceptible Salem population was cultured continuously for four generations without exposure to insecticides and the baseline toxicity data were established by leaf dip bioassay method (IRAC method No. 8). The tentative discriminating doses fixed, based on the susceptible A. biguttula biguttula population, were 1.10, 0.10, 0.02 and 1.0 ppm for imidacloprid, thiamethoxam, acetamiprid and thiacloprid, respectively. Insecticide resistance was then monitored using the above doses against leafhoppers collected from Coimbatore, Bhavanisagar, Salem and Srivilliputhur. The level of resistance in A. biguttula biguttula, as revealed by per cent survival, varied from 6.67 (Salem) to 15.38 (Srivilliiputhur) for imidacloprid; 3.33 (Salem) to 15.09 (Srivilliputhur) for thiamethoxam; 5.00 (Bhavanisagar) to 20.00 (Srivilliputhur) for acetamiprid; and 5.00 (Bhavanisagar) to 9.09 (Srivilliputhur) for thiacloprid. © 2014 © 2014 Taylor & Francis.

Singh K.P.,Vivekananda Institute of Hill Agriculture | Mishra H.N.,Indian Institute of Technology Kharagpur | Saha S.,Vivekananda Institute of Hill Agriculture
Journal of Food Engineering | Year: 2010

The geometric mean diameter, sphericity, grain surface area, 1000 grain mass, true density (toluene displacement method), terminal velocity, dynamic angle of repose, coefficient of internal friction, coefficient of static friction at different surfaces (sun mica, canvas and mild steel surfaces), specific deformation and rupture energy of the grain were found to increase 12.21%, 4.79%, 30.47%, 30.75%, 6.74%, 32.99%, 127.05%, 60%, 18.57%, 34-67%, 69.2% and 88.87% respectively at increase of moisture content from 0.065 to 0.265 kg kg-1 dry matter. However, true density (proximate composition method), bulk density, interstices and rupture force of grain was found to be decrease 8.64%, 20.1%, 86.49% and 21.17% respectively at increase of moisture content. Similar trend was observed for barnyard kernel also. True density (toluene displacement method) was found lower as compared to true density (proximate composition method) at all experimental moisture range indicated that the presence of void space inside the grain and kernel. © 2009 Elsevier Ltd. All rights reserved.

Discover hidden collaborations