scholarly journals Nonlethal Effects of Pesticides on Web-Building Spiders Might Account for Rapid Mosquito Population Rebound after Spray Application

2021 ◽  
Vol 11 (4) ◽  
pp. 1360
Author(s):  
Stefan N. Rhoades ◽  
Philip K. Stoddard

Spiders are important population regulators of insect pests that spread human disease and damage crops. Nonlethal pesticide exposure is known to affect behavior of arthropods. For spiders such effects include the inability to repair their webs or capture prey. In this study, nonlethal exposure of Mabel’s orchard spider (Leucauge argyrobapta) to the synthetic pyrethroid permethrin, via web application, interfered with web reconstruction and mosquito capture ability for 1–3 days. The timing of this loss-of-predator ecosystem function corresponds to the rapid population rebound of the yellow fever mosquito (Aedes aegypti) following insecticide application to control arbovirus epidemics. We suggest this temporal association is functional and propose that follow-up study be conducted to evaluate its significance.


2020 ◽  
Vol 20 (2) ◽  
Author(s):  
James R Hagler ◽  
Scott A Machtley

Abstract A follow-up study was conducted to further evaluate the marking efficiency of broadcast spray applications of egg albumin (from chicken egg whites) on Hippodamia convergens Guérin-Méneville (Coleoptera: Coccinellidae) in alfalfa. A previous study recorded exceptional marking efficiency (e.g., >95% of the population) on H. convergens when using relatively high concentrations (10 to 50%) of chicken egg whites. The present study examines marking efficiency of egg whites using lower concentrations of 2.5, 5.0, and 10.0%. We used cadaver and free-roaming beetles to measure protein mark acquisition (and retention) of each protein concentration by direct contact with the spray application and incidental contact with protein residue on the plant tissue, respectively. The vertical distribution of the protein mark was also determined by sampling the upper and lower portions of the alfalfa canopy. The data indicate, regardless of the egg white treatment, that the backpack sprayer provided uniform coverage of egg albumin on the alfalfa plants and cadaver beetles. Also, almost every free-roaming beetle acquired a mark within 24 h after contact exposure to protein marked plants. This study shows that a very low concentration of egg albumin is sufficient for marking arthropods directly in the field.



Author(s):  
C. Wolpers ◽  
R. Blaschke

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.



1997 ◽  
Vol 24 (10) ◽  
pp. 713-717 ◽  
Author(s):  
R. NAPANKANGAS ◽  
M.A.M. SALONEN ◽  
A.M. RAUSTIA


1973 ◽  
Vol 108 (4) ◽  
pp. 551-553 ◽  
Author(s):  
S. K. Gottlieb


2001 ◽  
Vol 120 (5) ◽  
pp. A628-A628
Author(s):  
P CLEMENS ◽  
V HAWIG ◽  
M MUELLER ◽  
J SCAENZLIN ◽  
B KLUMP ◽  
...  


2004 ◽  
Vol 171 (4S) ◽  
pp. 194-195
Author(s):  
Kyoichi Tomita ◽  
Haruki Kume ◽  
Keishi Kashibuchi ◽  
Satoru Muto ◽  
Shigeo Horie ◽  
...  


JAMA ◽  
1965 ◽  
Vol 194 (3) ◽  
pp. 227-232 ◽  
Author(s):  
S. Livingston
Keyword(s):  


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