Insecticide concentration for ultra-low volume crop spray application

1973 ◽  
Vol 4 (1) ◽  
pp. 77-82 ◽  
Author(s):  
D. R. Johnstone
2011 ◽  
Vol 25 (1) ◽  
pp. 77-83 ◽  
Author(s):  
Travis W. Gannon ◽  
Fred H. Yelverton

Experiments were initiated during 2003 and 2004 to evaluate application placement equipment for plant growth regulator (PGR) applications along bahiagrass roadsides. Recently designed equipment combine low-volume application and pesticide placement technology. Application placement equipment conceal the image of a traditional spray application. Evaluated application placement equipment included a wet-blade mower (Burch Wet Blade) and rotary-wick applicator (Weedbug™) compared with a traditional broadcast spray. Wet-blade mowers are designed to mow and simultaneously apply a pesticide solution to a cut stem or leaf in a single pass, whereas rotary-wick applicators are designed to wick a solution onto foliage. Evaluated PGRs included imazapic (9, 35, or 53 g ha−1) and sulfometuron-methyl (26 g ha−1). Bahiagrass injury varied with application placement equipment and was greater with rotary-wick applications in 2003, compared with foliar broadcast applications and the wet-blade mower. Bahiagrass seedhead suppression ranged from 31 to 60% with application placement equipment in July 2003 compared with 93% for a broadcast spray. In 2004, rotary wick- or broadcast-applied PGRs provided excellent (> 90%) seedhead suppression. Although application placement equipment may have advantages to broadcast-spray applications, evaluated equipment did not enhance bahiagrass suppression along roadsides in North Carolina compared with a foliar broadcast spray. Additional research is needed to determine if this type of application may provide consistent results with other species and compounds.


2006 ◽  
Vol 16 (2) ◽  
pp. 257-261 ◽  
Author(s):  
Peter M.A. Toivonen ◽  
Pascal Delaquis

Use of sprays to sanitize and treat apple (Malus ×domestica) slices helps to reduce the potential for cross-contamination that can occur when treatments are done in dip tanks. This research examined several factors that may affect the efficacy of spray treatments: 1) spray volume; 2) efficacy of spray application of anti-browning solution (ABS) compared with dipping; 3) effect of slice density during spraying; and 4) effect of the addition of an antimicrobial compound, vanillin, on microbiologically associated browning. Low-volume sprays (36-50 mL·kg-1 slices) of ABS gave maximal control of browning and this was equivalent to the control afforded by a 2-minute dip in the ABS. Spray application resulted in significant reduction in incidence and severity of microbiologically associated “secondary browning” as compared with dip application. However, if more than one layer of slices were present on the support mesh during the spray treatment, then secondary browning increased. This was attributed to potential cross-contamination between layers of apples in the spray treatment. Addition of vanillin into the ABS resulted in a 50% reduction of the incidence of “secondary browning.” Low-volume spray applications of ABS can be managed such that the microbiologically associated “secondary browning” is much lower than possible with dip application.


1997 ◽  
Vol 37 (5) ◽  
pp. 591 ◽  
Author(s):  
S. A. Bound ◽  
M. J. Oakford ◽  
K. M. Jones

Summary.Low volume, fine-droplet hollow cone (HC) Delavan nozzles were fitted to a conventional airblast machine in an attempt to reduce both the volume of spray and the dosage of chemical to thin apples. Red ‘Delicious’ trees at the Grove Research Station in southern Tasmania were thinned with ethephon at full bloom and the post-bloom thinner 6-benzyladenine at 20 days after full bloom. An unthinned control was compared with a treatment hand-thinned at 20 days after full bloom and chemically thinned treatments. The chemical sprays were applied with an airblast sprayer at high volume using conventional nozzles or Delavan HC nozzles at 50, 100, 200, 400 or 800 L/ha at 50, 75 or 100% of the dosage used at high volume. Most chemical treatments had some effect on the parameters measured when compared with the unthinned control while some were as effective as the hand-thinned treatment. The most consistent treatments were at 200 L/ha at the 75 and 100% dosages. Higher or lower volumes tended to be less effective, however, this could have been caused by either spray drift or evaporation of the smaller droplets used at these volumes. Although reducing the dosage to 75% did not reduce thinning effects, reduction of dosage to 50% resulted in significantly less thinning. These results offer a breakthrough for many orchardists to convert to low volume spray application very economically using the Delavan HC nozzles which produce a better droplet size than traditional high volume hydraulic nozzles. It also offers possibilities to significantly lower chemical usage by reducing dosage of chemical applied per hectare. Even more important is the reduction of wastage and pollution.


Agriculture ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 615
Author(s):  
Costas Michael ◽  
Emilio Gil ◽  
Montserrat Gallart ◽  
Menelaos C. Stavrinides

Leaf deposit and ground losses generated from spray application in mountain viticulture were evaluated. Four treatments were examined: A spray gun (1000 L ha−1, High-Volume Sprayer—HVS), a motorized knapsack sprayer (200 L ha−1, Low Volume Sprayer—LVS), and a conventional orchard mist blower calibrated at 500 L ha−1 (OS500) or 250 L ha−1 (OS250). The four treatments were assessed using the same tank concentration of tracer in two training systems: a trellis and a goblet. Sprayer treatment, vine side, and vine height significantly affected leaf deposit (p < 0.05). The absolute amount of leaf deposit increased with application volume, but when the amount of deposit was standardized to 1 kg ha−1, LVS resulted in the highest deposit, followed by HVS, OS250, and OS500. Deposition for the goblet system was ca. half that for the trellised vineyard. Ground losses standardized to 1 kg of tracer ha−1 were twice as high for HVS than for LVS, and four times as high for HVS than for OS250 and OS500, in both training systems. The current work suggests that low volume applications in vineyards are a viable and more environmentally friendly alternative than high volume treatments.


2021 ◽  
Vol 68 (1) ◽  
pp. 63-69
Author(s):  
Vindhya S. Aryaprema

Sterile insect technique (SIT) using irradiated mosquitoes is an effective control method capable of being assimilated into integrated vector management (IVM) programs. Chemical control of mosquitoes using ultra-low volume (ULV) spray applications of pyrethroid and organophosphate insecticides is already an essential component of IVM programs. Prior to their release in nature, irradiation of mosquitoes for SIT use can significantly impact the mosquito’s biology, specifically its host-seeking and feeding behavior. Little is known about how radiation exposure might impact a mosquito’s susceptibility to pyrethroid insecticides. The present study was carried out to evaluate the influence of Aqualuer ® 20-20 ULV applications on irradiated Aedes aegypti. Caged mosquito trials indicated that both male and female irradiated Ae. aegypti were as susceptible as their non-irradiated counterparts of the same population to Aqualuer 20-20 ULV application, with the highest mean percent mortalities achieved at the first 24h post-treatment period at both 30.5 m and 61 m downwind of the spray application path.


Author(s):  
Costas Michael ◽  
Emilio Gil ◽  
Montserrat Gallart ◽  
Loukas Kanetis ◽  
Menelaos C. Stavrinides
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document