Knockdown test

INSPECTION AND DAMAGE THRESHOED. The apple blossom weevil is monitored mainly by means of the knockdown test. 

The knockdown tests should therefore be continued after spraying. 

INSPECTION AND DAMAGE THRESHOED. Infestation is monitored by means of the knockdown test. The brown leaf weevil has occurred in very large numbers in recent years. Knockdown tests with 200-300 brown leaf weevil beetles/100 branches are quite common. 

INSPECTION AND DAMAGE THRESHOLD. Monitoring is very difficult, as the beetles cling to the branches very securely and are very difficult to detect with the knockdown test. The infestation in the previous year is very important. Infestation can increase very severely in 2-3 years and, starting from just a few trees, spread to the entire orchard. 

In recent years there has been natural regulation of pear suckers by hoverfly larvae in June. The hoverfly appears to develop better in cold, wet periods than the anthocorid bug. In knockdown tests and visual inspections, 80% of the predators were hoverflies. 

The edible parts of parsnips (Pastimea sativa L.), which have been consumed for centuries by humans without causing any obvious harm, were found to contain a chemical of insecticidal and strong synergistic nature (1). The insecticidal constituent, present at about 200 p.p.m., was isolated and identified as 5-allyl-l-methoxy-2, 3-methylenedioxybenzene or myristicin. Its toxicity to various insects [vinegar flies, houseflies, Mediterranean fruit flies, mosquito larvae, Mexican bean beetles, and pea aphids] was established and compared with pyrethrum and aldrin (Tables I and II). The knockdown effect, although definite, was not as great as that of pyrethrum. In tests... 

Table VI. The knockdown power of the organofluorine insecticides has been determined principally against members of the Diptera order and by a limited number of workers. There is general agreement that DFDT acts more rapidly than DDT, at least against those species with which they have been compared. Prill 92) found that twice the amount of DFDT compared to DDT was required to give the same knockdown against houseflies when tested by a space spray technique with added pyrethrins. The forced contact method of Fay and Buckner 27) revealed that without added pyrethrins DFDT was a more powerful knockdown agent than DDT.

Difluorodiphenyl disulfide, when tested on woolen swatches, is an outstanding knockdown agent and toxicant for body lice. Several compounds with p-fluorinated phenyl radicals have exhibited the same order of activity against lice, but too few compounds with the disulfide linkage have been tested to warrant an appraisal of its effect here. 

Metofluthrin is a suitable active ingredient for various formulations and devices due to its high lethal/knockdown activity against pest insects (especially mosquitoes), as well as having low mammalian toxicity and favorable physicochemical properties. This report summarizes its outstanding efficacy in various mosquito control formulations in both laboratory tests and field trials [2],... 

In Vitro lox-STOP-lox Cassette Excision and Testing stiRNA Knockdown Efficiency In ES Cells... 

Subheading 3.1.3, step 5 The knockdown efficiency of stably integrated vectors should be tested in ES cells with the additional necessity of activating the integrated vectors by Cre before testing them (see Note 9). 

A measure of the effectiveness of a defoamer. First, a column of foam is generated in a foam stability apparatus and the foam height is recorded. A measured amount of defoamer is added, and the reduction in foam height over a specified time period, for example, 2 s, is noted. The knockdown capability is the reduction in foam height. This test has many variations. Sometimes referred to as initial knockdown capability . 

The animals present are knocked down from the branches with a knockdown funnel. This type of test is especially important in the case of the blossom weevil and should be carried out around midday, when the temperature is high (>12°C). 

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