A new systemic Insecticide bis (bis dimethylamino phosphonous) anhydride

The general insecticidal properties of bis (his-dimethylamino phosphonous) anhydride (anhydride), bis (dimethylamino) fluorophosphine oxide (oxide), diethyl paranitro-phenyl phosphate (E ~o o ) , and sodium fluoroacetate (acetate) are described. All are toxic to aphids when infested plants are dipped in solutions. Although this is thought to be a contact action the possibility that the materials are first absorbed by the leaves and that the aphids are killed by imbibing toxic sap is not excluded. The order of decreasing toxicity by dipping is E6oo>acetate> anhydride =oxide. At the lowest concentration giving a complete kill of aphids, the anhydride is the most persistently effective of the four compounds. E6oo is the most phytotoxic compound.When applied to the roots the order of decreasing toxicity is acetate>oxide > anhydride > E 600 in sand and soil, and acetate > oxide > anhydride = E 600 in culture solution. The anhydride and acetate are more persistent in the plants than the oxide and E600. The margin of safety between insecticidal dosage and phytocidal dosage is appreciably larger with the acetate than with the other three compounds. When equal dosages are administered to plants by the cut tap root technique the order of decreasing toxicity to aphids is seen to be acetate > oxide > E6oo > anhydride. All compounds, except possibly E600, appear to be absorbed by the intact roots of the plants. Systemic insecticidal action following application made to the leaves of the broad bean is easy to demonstrate with the acetate, demonstrable with difficulty with the anhydride and not at all with E6oo and the oxide.Only the oxide is sufficiently volatile to kill insects by a fumigant effect either as the pure substance or after absorption into the plant. Plants treated with it give off a toxic vapour which may be collected by condensation and shown to be systemically active. The material concerned is presumed to be the unchanged oxide.Sodium fluoroacetate is an extremely effective systemic insecticide whether applied to the leaves or the roots of the broad bean. It is apparently not phytotoxic at several times the concentration necessary for insecticidal action but may prove to be too generally toxic or persistent for practical use.

Section: Introductionsupporting

confidence: 56%

INVESTIGATIONS ON THE SYSTEMIC INSECTICIDAL ACTION OF SODIUM FLUOROACETATE AND OF THREE PHOSPHORUS COMPOUNDS ON APHIS FABAE SCOP.

David

Gardiner

1951

“…B. brassicae was studied in pioneer attempts at integrated control by Ripper (1944), who demonstrated the selective action of nicotine, and by Ripper, Greenslade & Hartley (1950) who concluded that the selective action of the systemic insecticide schradan preserved natural enemies which then prevented immediate aphid resurgences such as those caused by the non-selective contact insecticide parathion.…”

Section: Introductionmentioning

confidence: 99%

Experiments on integration of chemical and biological control of aphids on brussels sprouts

Way

Murdie

Galley

1969

S U M M A R YTwo field experiments were made to test whether natural enemies would take over control of brussels sprouts aphids at the time when protection from a selectively acting, soil-applied systemic insecticide, menazon, began to fail,The natural enemies, notably Syrphidae, proved ineffective against Brevicoryne brassicae L. despite advantages given by the insecticide and by close planting, which greatly increased the ratio of numbers of syrphid eggs and larvae to aphids. Thus, development of the aphid population was little altered when infested plants were kept free of most natural enemies by hand removal. I lb/acre (1.12 kg/ha) of menazon applied as spot treatments to the soil at planting-out time decreased the number of overwintering parasite mummies 30 App. Biol. 63 T h e field experiments were done in I acre (0.4 ha) adjacent halves of a field in Hill Bottom, Silwood Park, in land fertilized with 40 tons (40640 kg) of cow manure and 8 cwt (406.4 kg) of artificial (20% N, 9-3 yo P,O, (soluble), 1o0/" K,O) per acre. The mechanical analysis of the sandy loam soil was: < 2 p diam. = 8.8 yo ; 2-20 p = 7.5%; 21-50p = 8.2%; 51-200p = 41'4%; 201 p -2 m m diam. = 34'9%. I n 1963 three blocks of plots were split for normal (plants 3 ft apart) and close (I ft 6 in apart) spacing. Each half block was divided into four approximately I 2 x Io yd ( I I x 9 m)

“…It is well known that the anhydride is absorbed by the leaves of certain plants and translocated in insecticidal quantities (Ripper, Greenslade & Hartley, 1950;David, 1951). A similar effect has not been reported with the oxide, and indeed it seems possible that if absorption does occur through the leaves the material might be so 14-2 readily lost again by vaporization that it would not be transported very far from the point of absorption.…”

Section: Penetration and Translocation Following Application Of The Omentioning

confidence: 84%

INSECTICIDAL‐ACTION STUDIES WITH BISDIMETHYL‐AMINO FLUOROPHOSPHINE OXIDE CONTAINING ³²PHOSPHORUS

David¹

1952

T h e absorption of the systemic insecticide bisdimethylamino fluorophosphine oxide containing 32P by plants has been studied, and where possible comparisons have been made with bisdimethylaminophosphonous anhydride.The radio-oxide is absorbed by the roots of a broad-bean plant from culture solutions. The level of radioactivity in the plant increases as the solution is absorbed and is higher in the washed roots than in the rest of the plant. The radioactivity of the remaining culture solution decreases as more of it is taken up by the plants showing that the roots selectively absorb the oxide from solution. In this latter respect it differs from the anhydride which is selectively rejected at similar rates of transpiration. The material is absorbed more slowly by plants growing in soil than in sand.An appreciable part of the oxide absorbed by the roots is given off as vapour by the leaves. The transpired material can be collected and shown to be radioactive and systemically insecticidal. Aphids feeding on treated plants contain radioactive material.The oxide is less lipoid soluble than the anhydride and does not penetrate as readily into the leaves of the broad bean. Since it is also lost by vaporization from the plants only small amounts are translocated following leaf applications to beans, cabbages and hops.