BIOLOGICAL ACTIVITY OF CHLORPYRIFOS, CHLORPYRIFOS-METHYL, PHORATE, AND COUNTER® IN SOIL

1977 ◽  
Vol 109 (8) ◽  
pp. 1115-1120 ◽  
Author(s):  
C. R. Harris
Keyword(s):  
Biological Activity ◽  
Chemical Structure ◽  
Mineral Soil ◽  
Initial Activity ◽  
Organophosphorus Insecticides ◽  
Third Stage ◽  
Good Potential ◽  
Euxoa Messoria ◽  
Soil Insecticides ◽  
Northern Corn Rootworm

AbstractThe potential of chlorpyrifos-methyl and Counter® (S-[tert-butylthio) methyl] O, O-diethyl phosphorodithioate) as soil insecticides was assessed in the laboratory. Two established soil insecticides, chlorpyrifos and phorate, which are similar in chemical structure to chlorpyrifos-methyl and Counter respectively were included for comparative purposes. Spectrum of activity was determined using 24–48 h crickets, Acheta pennsylvanicus (Burmeister), 24–48 h adults, Chaetopsis spp., third stage darksided cutworms, Euxoa messoria (Harris), northern corn rootworm adults, Diabrotica longicornis (Say), and honeybees, Apis mellifera L. Chlorpyrifos-methyl and chlorpyrifos showed the broadest spectrum of activity being toxic to all five species of insects; Counter and phorate were toxic to four of the five. Initial activity in soil was assessed relative to soil type, moisture, and temperature using crickets as the indicator species. Chlorpyrifos-methyl was as effective and more consistent in activity than chlorpyrifos. Counter was more effective and consistent in soil than phorate other than under conditions of low soil moisture. No clear relationship between chemical structure and either direct contact or initial toxicity in soil was apparent. Tests on persistence of biological activity in mineral soil indicated that, as is generally the case with dimethyl and diethyl forms of organophosphorus insecticides, chlorpyrifos-methyl was even less persistent than chlorpyrifos. Counter was slightly more persistent than phorate. Although very active the potential of chlorpyrifos-methyl as a soil insecticide would be restricted by its limited persistence. Counter was considered to have good potential.

LABORATORY ASSESSMENT OF THE POTENTIAL OF 16 EXPERIMENTAL COMPOUNDS AS SOIL INSECTICIDES

1977 ◽  
Vol 109 (8) ◽  
pp. 1109-1114 ◽  
Author(s):  
C. R. Harris ◽  
S. A. Turnbull
Keyword(s):  
Biological Activity ◽  
Field Cricket ◽  
Corn Rootworm ◽  
Laboratory Assessment ◽  
Moist Sand ◽  
Third Stage ◽  
Good Potential ◽  
Euxoa Messoria ◽  
Soil Insecticides ◽  
Northern Corn Rootworm

AbstractThe effectiveness of 16 experimental compounds as soil insecticides was assessed under laboratory conditions. Chlorpyrifos, carbofuran, and dieldrin were included as standard insecticides. Spectrum of activity as contact insecticides was determined using 24–48 h nymphs of the field cricket, Acheta pennsylvanicus (Burmeister), 24–48 h onion maggot adults, Hylemya antiqua (Meigen), third stage darksided cutworms, Euxoa messoria (Harris), northern corn rootworm adults, Diabrotica longicornis (Say), and honeybees, Apis mellifera L. First stage crickets were used to assess the biological activity of experimental compounds relative to soil type, moisture, and temperature and also their volatility in moist sand and persistence of biological activity over a 48 week period. All of the insecticides showed broad spectrum contact activity. Twelve showed fair to very good potential in soil. Four insecticides, Shell WL 24794 (O,O-dimethyl-S-1-[3-(5-methyl-1,2,4-oxadiazolyl)] ethyl phosphorodithioate), Shell WL 25735 (O-[2-chloro-1-(2,5-dichlorophenyl) vinyl] O-methyl methylphosphonothioate), Shell WL 26738 (O-[1-(2,4-dichlorophenyl) vinyl] O-methyl ethylphosphonothioate), and chlorpyrifos-methyl showed good potential. Two others, Counter® (S-[(tert-butylthio) methyl] O,O-diethyl phosphorodithioate) and Shell WL 24073 (O-[2-chloro-1-(2,5-dichlorophenyl) vinyl] O-methyl ethylphosphonothioate) were considered to have very good potential as soil insecticides.

LABORATORY STUDIES ON THE CONTACT TOXICITY AND ACTIVITY IN SOIL OF FOUR PYRETHROID INSECTICIDES

1978 ◽  
Vol 110 (3) ◽  
pp. 285-288 ◽  
Author(s):  
C. R. Harris ◽  
S. A. Turnbull
Keyword(s):  
Soil Moisture ◽  
Mineral Soil ◽  
Negative Temperature ◽  
Field Cricket ◽  
Contact Toxicity ◽  
Pyrethroid Insecticides ◽  
Effective Contact ◽  
Euxoa Messoria ◽  
Soil Insecticides ◽  
Northern Corn Rootworm

AbstractThe spectrum of contact toxicity and activity in soil of four pyrethroid insecticides was assessed in the laboratory. Pyrethroids tested were: FMC 33297 (3-phenoxybenzyl (±)-3-(2, 2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate); Shell WL 41706 (alpha-cyano-3 phenoxybenzyl 2,2,3,3-tetramethylcyclopropanecarboxylate); Shell WL 43467 (alpha-cyano-3-phenoxybenzyl 2-(2,2-dichlorovinyl)-3,3-dimethylcyclopropane-1-carboxylate); and Shell WL 43775 (alpha-cyano-3-phenoxybenzyl-2-(4-chlorophenyl)-3-methyl-1-butyrate). Chlorpyrifos and carbofuran, two broad spectrum contact and soil insecticides were included for comparative purposes. Spectrum of contact toxicity was determined using 24–48 h nymphs of the common field cricket, Acheta pennsylvanicus (Burmeister), 24–48 h onion maggot adults, Hylemya antiqua (Meigen), 3rd instar dark sided cutworms, Euxoa messoria (Harris), northern corn rootworm adults, Diabrotica longicornis (Say), and honeybees, Apis mellifera L. Crickets were used to assess insecticidal activity in soil relative to soil moisture, type, and temperature. The pyrethroids were effective contact insecticides comparable in toxicity and spectrum of activity to chlorpyrifos and carbofuran. They were particularly toxic to the darksided cutworm. They were less effective in mineral soil than chlorpyrifos. WL 43467 showed activity in mineral soil close to that of carbofuran, while the other pyrethroids were less active. Activity in soil was influenced by soil moisture and type. In contrast to the standard insecticides the pyrethroids generally showed a negative temperature coefficient of toxicity in soil.

scholarly journals Electrochemically Produced Copolymers of Pyrrole and Its Derivatives: A Plentitude of Material Properties Using “Simple” Heterocyclic Co-Monomers

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 281
Author(s):  
Tomasz Jarosz ◽  
Przemyslaw Ledwon
Keyword(s):  
Biological Activity ◽  
Material Properties ◽  
Building Block ◽  
Conjugated Polymer ◽  
Chemical Structure ◽  
Heterocyclic System ◽  
Repeat Unit ◽  
Polymeric Materials ◽  
Pyrrole Derivatives ◽  
Pyrrole Monomer

Polypyrrole is a classical, well-known conjugated polymer that is produced from a simple heterocyclic system. Numerous pyrrole derivatives exhibit biological activity, and the repeat unit is a common building block present in the chemical structure of many polymeric materials, finding wide application, primarily in optoelectronics and sensing. In this work, we focus on the variety of copolymers and their material properties that can be produced electrochemically, even though all these systems are obtained from mixtures of the “simple” pyrrole monomer and its derivatives with different conjugated and non-conjugated species.

scholarly journals Chemical Structure and Biological Activity of Humic Substances Define Their Role as Plant Growth Promoters

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2256
Author(s):  
Serenella Nardi ◽  
Michela Schiavon ◽  
Ornella Francioso
Keyword(s):  
Biological Activity ◽  
Humic Substances ◽  
Chemical Structure ◽  
Molecular Size ◽  
Growth Promoters ◽  
Root Cells ◽  
Sustainable Technologies ◽  
Intracellular Signals ◽  
Key Functional Groups ◽  
Regulatory Functions

Humic substances (HS) are dominant components of soil organic matter and are recognized as natural, effective growth promoters to be used in sustainable agriculture. In recent years, many efforts have been made to get insights on the relationship between HS chemical structure and their biological activity in plants using combinatory approaches. Relevant results highlight the existence of key functional groups in HS that might trigger positive local and systemic physiological responses via a complex network of hormone-like signaling pathways. The biological activity of HS finely relies on their dosage, origin, molecular size, degree of hydrophobicity and aromaticity, and spatial distribution of hydrophilic and hydrophobic domains. The molecular size of HS also impacts their mode of action in plants, as low molecular size HS can enter the root cells and directly elicit intracellular signals, while high molecular size HS bind to external cell receptors to induce molecular responses. Main targets of HS in plants are nutrient transporters, plasma membrane H+-ATPases, hormone routes, genes/enzymes involved in nitrogen assimilation, cell division, and development. This review aims to give a detailed survey of the mechanisms associated to the growth regulatory functions of HS in view of their use in sustainable technologies.

Biological Activity of Humic Substances Is Related to Their Chemical Structure

2007 ◽  
Vol 71 (1) ◽  
pp. 75-85 ◽  
Author(s):  
Adele Muscolo ◽  
Maria Sidari ◽  
Emilio Attinà ◽  
Ornella Francioso ◽  
Vitaliano Tugnoli ◽  
...  
Keyword(s):  
Biological Activity ◽  
Humic Substances ◽  
Chemical Structure

Cytokinin activity of some substituted ureas and thioureas

1966 ◽  
Vol 165 (999) ◽  
pp. 245-265 ◽  
Keyword(s):  
Biological Activity ◽  
Active Compound ◽  
Phenyl Ring ◽  
Chemical Structure ◽  
Lower Activity ◽  
Cytokinin Activity ◽  
Hydrogen Atoms ◽  
Detectable Activity ◽  
Low Activity

N , N '-Diphenylurea was shown to have reproducible cytokinin activity . Some 500 ureas, mainly of the N -monosubstituted and N , N '-disubstituted types, were tested an d about one half of these were active. Attempts were made to correlate chemical structure with biological activity. Although there are some exceptions to nearly every generalization it has been possible to formulate some principles. (1) Phenyl urea was the simplest active compound. (2) An HNCONH bridge conferred higher activity than an HNCSNH linkage and any other tested arrangement of the bridge gave inactive com pounds. (3) Compounds in which both amino hydrogen atoms on one or both sides of the bridge were substituted were of low activity or were inactive. (4) Many com pounds of the type R NHCONH 2 in which R = a substituted phenyl ring were tested. Ring substitution generally increased the activity and the highest activity was associated with meta substitution and the lowest with ortho . Compounds with electron-attracting substituents were generally more active than those with electron-donating substituents. Pyridyl compounds were active but com pounds with non-planar rings were inactive. (5) In compounds of the type R NHCONH R ' in which R and R ' were phenyl or substituted phenyl groups the highest activities were usually found in com pounds with one unsubstituted phenyl ring. Those with two substituted phenyl groups generally had lower activity. Some ureas showed detectable activity at 0.1 parts/10 6 . This was about four times less active than kinetin when tested in the tobacco pith assay.

Sign in / Sign up

Export Citation Format

Share Document