is important to assess the impact of pesticides on the mycorrhizal association. The insecticide bifenthrin is a synthetic pyrethroid used for the production of nursery crops to suppress the red imported fire ant in quarantined areas of Orange and
Lea Corkidi, Jeff Bohn, and Mike Evans
Christopher T. Werle, Karla M. Addesso, Blair J. Sampson, Jason B. Oliver, and John J. Adamczyk
are 1) to assess the efficacy of kaolin, both alone and with an insecticide (bifenthrin), for reducing ambrosia beetle attacks over time; and 2) to determine whether there is any correlation between abandoned vs. completed beetle galleries. Materials
Russell S. Harris*, Edward W. Bush*, and Ronald J. Ward
Bifenthrin and fipronil are important pesticides used in the nursery industry for the control of imported fire ants. Our research measured the influence of irrigation frequency and time on the degradation of bifenthrin and fipronil in pine bark nursery medium. Pine bark media leachates were collected over a 180-d period. Levels of bifenthrin, fipronil, and metabolites of fipronil (MB 46513, MB 45950, MB 46136) were measured using gas chromatography and mass spectrophotometery. Bifenthrin leachate concentrations decreased from 60 ppb on day 1 to ≈1 ppb after 120 d. Fipronil leachate concentrations decreased from 40 ppb on day one to a low of 15 ppb after 120 d. In contrast, metabolites MB 45950 and MB 46136 gradually increased over the 180-d period. Metabolite MB 46513 was not detected during the experiment. Pine bark medium leachate concentrations of bifenthrin and fipronil were greater than previously reported levels in pure water. We theorize that organic compounds present in pine bark may have increased the solubility of these chemicals.
James D. Spiers, Fred T. Davies Jr., Chuanjiu He, Carlos E. Bográn, Kevin M. Heinz, Terri W. Starman, and Amanda Chau
This study evaluated the influence of insecticides on gas exchange, chlorophyll content, vegetative and floral development, and plant quality of gerbera (Gerbera jamesonii Bolus `Festival Salmon'). Insecticides from five chemical classes were applied weekly at 1× or 4× their respective recommended concentration. The insecticides used were abamectin (Avid), acephate (Orthene), bifenthrin (Talstar), clarified hydrophobic extract of neem oil (Triact), and spinosad (Conserve). Photosynthesis and stomatal conductance were reduced in plants treated with neem oil. Plants treated with neem oil flowered later—and at 4× the recommended label concentration had reduced growth, based on lower vegetative dry mass (DM) and total aboveground DM, reduced leaf area, thicker leaves (lower specific leaf area), higher chlorophyll content (basal leaves), and reduced flower production. Plants treated with acephate at 4× the recommended label concentration were of the lowest quality due to extensive phytotoxicity (leaf chlorosis). Plants treated with 1× or 4× abamectin or spinosad were of the highest quality due to no phytotoxicity and no thrips damage (thrips naturally migrated into the greenhouse). The control plants and plants treated with 1× bifenthrin had reduced quality because of thrips feeding damage; however gas exchange was not negatively affected.
Carlos R. Quesada, Adam Witte, and Clifford S. Sadof
., 2001 ; Rebek and Sadof, 2003 ). Dinotefuran and bifenthrin were chosen to represent the two most commonly used broad-spectrum insecticide classes, neonicotinoids, and pyrethroids ( Sparks and Nauen, 2015 ). All insecticides were applied using the
Salvatore S. Mangiafico, Julie Newman, Donald J. Merhaut, Jay Gan, Ben Faber, and Laosheng Wu
mg·L −1 , but concentrations varied by nursery ( Mangiafico et al., 2008 ). Monitoring runoff from a 100-acre production nursery in southern California found bifenthrin concentrations up to 960 ng·L −1 , and cis- and transpermethrin up to 1450 and 270
J. J. Knabke and H. G. Hancock
Talstar 10WP insecticide/Miticide (bifenthrin) is used for the control of a broad spectrum of economic pests on ornamentals. Over 100 species of greenhouse and field–grown plants, trees and shrubs have been shown to exhibit no phytotoxic response to the wettable powder formulation. Research efforts with alternative bifenthrin, formulations, which exhibit equivalent pest efficacy and lack of phytotoxicity, may also provide unique application opportunities.
Raymond A. Cloyd
abamectin (Avid®; Syngenta Professional Products, Greensboro, NC) and bifenthrin (Talstar®; FMC, Philadelphia, PA) for control of mite, whitefly, mealybug, and aphid. The two-way tank mixtures cited six times by the survey respondents included abamectin and
J.C. Palumbo and C.A. Sanchez
Imidacloprid is a new, chloronicotinyl insecticide currently being used to control sweetpotato whitefly [Bemisia tabaci Genn, also known as silverleaf whitefly (Bemisia argentifolii Bellows and Perring)]. Large growth and yield increases of muskmelon (Cucumis melo L.) following the use of imidacloprid have caused some to speculate that this compound may enhance growth and yield above that expected from insect control alone. Greenhouse and field studies were conducted to evaluate the growth and yield response of melons to imidacloprid in the presence and absence of whitefly pressure. In greenhouse cage studies, sweetpotato whiteflies developed very high densities of nymphs and eclosed pupal cases on plants not treated with imidacloprid, and significant increases in vegetative plant growth were inversely proportional to whitefly densities. Positive plant growth responses were absent when plants were treated with imidacloprid and insects were excluded. Results from a field study showed similar whitefly control and yield responses to imidacloprid and bifenthrin + endosulfan applications. Hence, we conclude that growth and yield response to imidacloprid is associated with control of whiteflies and the subsequent prevention of damage, rather than a compensatory physiological promotion of plant growth processes. Chemical names used: 1-[(6-chloro-3-pyridinyl)methyl]-4,5-dihydro-N-nitro-1-H-imidazol-2-amine (imidacloprid); [2 methyl(1,1′-biphenyl)-3yl)methyl 3-2-chloro-3,3,3-trifluoro-1-propenyl]-2,2-dimethylcyclopropane carboxylate (bifenthrin); 6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodiaxathiepin 3-oxide (endosulfan).
James D. Spiers, Fred T. Davies, Chuanjiu He, Carlos Bogran, Amanda Chau, Kevin M. Heinz, and Terri W. Starman
This research focused on the influence of insecticides on gas exchange, chlorophyll content, vegetative and floral development, and overall plant quality of gerbera (Gerbera jamesonii var. `Festival Salmon'). Insecticides from five chemical classes were applied weekly at 1× and 4× the recommended concentrations. Insecticides used were: abamectin (Avid® 0.15 EC), acephate (Orthene® Turf, Tree & Ornamental Spray 97), bifenthrin (Talstar® Nursery Flowable), clarified hydrophobic extract of neem oil (Triact® 70), and spinosad (Conserve® SC). Phytotoxicity occurred in the form of leaf chlorosis on all acephate treatments, with the greatest damage occurring at the 4× concentration. Photosynthesis and stomatal conductance were significantly reduced in plants treated with neem oil extract. Plants treated with the neem oil extract (1× and 4×) flowered later and had reduced growth [lower shoot dry mass (DM) and total DM]. Plants that received 4× the recommended concentration of neem oil extract had reduced leaf area, thicker leaves (lower specific leaf area), higher leaf chlorophyll content, and reduced flower production, as determined by flower number and flower DM. Plants treated with acephate 4× concentration were the lowest quality plants due to extensive phytotoxicity (leaf burn), which also reduced photosynthesis. The highest quality plants were treated with spinosad and abamectin due to zero phytotoxicity and/or no thrips damage (thrips naturally migrated into the greenhouse). The control plants and plants treated with bifenthrin 1× were not marketable due to thrips damage; however, plant growth characteristics and gas exchange were not statistically different.