Calcium Arsenate and Lead Arsenate Sprays with Soybean Flour for Codling Moth Control1

1940 ◽  
Vol 33 (6) ◽  
pp. 862-865
Author(s):  
Lewis T. Graham ◽  
Charles H. Richardson
1929 ◽  
Vol 19 (3) ◽  
pp. 405-412
Author(s):  
W. Goodwin ◽  
H. Martin ◽  
E. S. Salmon

(1) A solution of dicalcium hydrogen arsenate at a strength of 0·0125 per cent. As2O5 was fungicidal to the conidial stage of Sphaerotheca Humuli, while at 0·006 per cent. As2O5 it was not quite fungicidal.(2) Lime casein containing calcium hydroxide when added as a spreader to calcium arsenate was shown to reduce the fungicidal properties of the calcium arsenate spray.(3) A solution of calcium thioarsenate at a strength equivalent to 0·006 per cent. As2O5 was fungicidal to the above fungus, while at 0·003 per cent. As2O5 it was below fungicidal strength.(4) It is suggested that the increased fungicidal properties of the mixed lime sulphur-lead arsenate spray are due to the presence of calcium thioarsenates.


1936 ◽  
Vol 29 (4) ◽  
pp. 658-669 ◽  
Author(s):  
J. Marshall ◽  
Kermit Groves

1964 ◽  
Vol 55 (1) ◽  
pp. 35-47 ◽  
Author(s):  
M. Gratwick

The toxicity of naturally weathered deposits of 21 chemicals to larvae of the codling moth, Cydia pomonella (L.), was assessed by spraying apple trees in the orchard and testing samples of the fruit picked at various intervals after treatment. Each apple was placed in a separate glass container with one first-instar larva from a laboratory culture, and larval mortality and damage to the fruit (defined as removal of a portion of the skin) were recorded after three days in a constant environment.The site of entry of the larvae was shown to vary with fruit size, calyx entries decreasing and side entries increasing with increase in the surface area of the fruit.The relationship between larvicidal activity and age of the spray deposit for periods up to ten weeks after spraying is illustrated graphically; data are presented for fruit damage caused by larvae applied one and three weeks after spraying.On the basis of larval mortality and fruit damage recorded in tests on deposits up to three weeks after application, a spray containing 0·1 per cent, carbaryl was the most effective, followed by 0·05 per cent, fenthion, while Bayer 5024, Zectran, DDT, DDD (all at 0·l per cent.) and 0·04 per cent, azinphos (as the methyl or ethyl homologue) were only slightly less effective. Deposits from 0·1 per cent. Kepone, 0·02 per cent, diazinon, 0·11 per cent, malathion, 0·01 per cent, parathion and 0·05 per cent, carbophenothion, dimethoate and ethion also caused 90–100 per cent, mortality when fresh, but were less persistent. Fresh deposits from 0·1 per cent, endosulfan, 0·04 per cent, dioxathion, 0·05 per cent, phenkapton, 0·02 per cent, phosphamidon, 0·2 per cent, lead arsenate and 0·6 per cent, ryania only killed 50–88 per cent, of the larvae, and their residual toxicity was proportionately low.Heavy rain soon after spraying caused a large reduction in deposits from wettable powders but the accompanying reduction in larvicidal activity was shown to be greater in the case of carbaryl than for DDT or DDD.


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