DE1141129B - Nematocidal agents - Google Patents

Description

GERMAN

PATENT OFFICE

F30261IVa / 451

REGISTRATION DATE: JANUARY 9, 1960

NOTICE
THE REGISTRATION
AND ISSUE OF
EDITORIAL: DECEMBER 13, 1962

A number of compounds have been proposed to control nematodes in soil. So are z. B. Mixtures of dichloropropene and dichloropropane, also sodium N-methyl-dithiocarbamate or methyl isothiocyanate is commercially available as a nematode control agent.

It has now been found that compounds of the general formula

Nematocidal agents

CH ₃

N — C — S — C —O —R

'Il Il

S O

in which R stands for a preferably lower, optionally substituted alkyl radical, i.e. N-methyldithiocarbamic acid formate, can be used individually or in a mixture with particular success for combating nematodes.

The preparations to be used according to the invention are distinguished from the known agents by an increased nematocidal effectiveness, which has the consequence that to complete destruction of the nematodes, particularly low amounts of active ingredient are required. The possibility of the required Reducing the application rate means, in turn, a shortening of the waiting period, that is the time from the application of the agent to the sowing of the relevant crops.

Finally, the compound class of the above formula has, in addition to its nematocidal properties also a considerable amount of soil fungicidal and insecticidal activity and during the waiting period even good herbicidal effectiveness. Because of this extraordinary broad impact, the products are generally used as soil disinfectants. According to the invention Active ingredients to be used are known in part (cf. Organic Syntheses, Vol. 21 [1941], P. 81).

The German Auslegeschrift 1 017 405 already describes fungicidal _{pesticides based on N 5} N-dimethyl-dithiocarbamic acid-formic acid esters. However, in contrast to the products according to the invention, these compounds have practically no nematocidal properties. In addition, the fungicidal and herbicidal effectiveness of the first-mentioned preparations is also much poorer. Thus, according to the applicant:

Paint factories Bayer Aktiengesellschaft,
Leverkusen

Dr. Rudolf Heusch, Cologne-Stammheim,

and Dr. Bernhard Homeyer, Opladen,
have been named as inventors

Information from the German Auslegeschrift 1017 405 on the formic acid derivatives of N, N-dimethyldithiocarbamic acids when used against soil-dwelling fungi and weeds, application rates of 200 to 4000 ppm are required, while to achieve the same effect in each case only 20 ppm of the compounds to be used according to the invention required are.

The above-mentioned preparations can be used as nematode control agents Inject, pour into the plow sole or onto the soil surface and then work in.

Depending on the type of soil to be treated, the use of the means is in the form of a solution or Emulsion possible.

example

The following derivatives of N-methylcarbamic acids were injected into the middle of 5-1 pots at the specified application rates, which were heavily contaminated with Meloidogyne incognita. The pots were covered at 25 ° C. for 1 week and were planted with tomatoes after 3 weeks. The evaluation was carried out after a further 5 weeks the tomato roots for nematode infestation. The following table shows the efficiencies for the appropriate application rates indicated. These efficiencies are mean values from three repeat tests. For the comparison means, the respective LDioo value is given, which consists of at least

209 747/318

ten test results was determined according to the above test methodology.

1. CH ₃ -NH-CS-S -CO-O-CH ₃

100 mg / 1 soil 100% kill, 80 mg / 1 soil 100% kill, 60 mg / 1 soil 100% destruction, 40 mg / 1 soil 100% destruction, 20 mg / 1 soil 100% destruction, 10 mg / 1 soil 50% destruction,

2. CH ₃ -NH-CS-S -CO-O-C ₂ H ₅

100 mg / 1 soil 100% destruction,

80 mg / 1 soil 100% destruction,

60 mg / 1 soil 100% destruction,

40 mg / 1 soil 90% destruction,

20 mg / 1 soil 50% destruction, 10 mg / 1 soil 0% destruction.

3. CH ₃ -NH-Cs-S-CO-O-CH ₂ -CH ₂ -Cl

100 mg / 1 soil 100% destruction, 80 mg / 1 soil 100% destruction, 60 mg / 1 soil 100% destruction, 40 mg / 1 soil 80% destruction, 20 mg / 1 soil 50% destruction, 10 mg / 1 soil 0% destruction.

4. Minimum application rate for 100% destruction in same experiment compared to known nematocidal agents (comparative agents):

Dichloropropane - dichloropropene 66 ppm

Na-N-methyl-dithiocarbamate 37 ppm

Methyl isothioeyanate 30 ppm

CH ₃ -NH-SC-S-CO-O-CH ₃ 20 ppm

Claims (1)

PATENT CLAIM: Nematocidal agents with simultaneous soil disinfectants Action containing N-methyldithiocarbamic acid formic acid ester the general formula CH ₃ N — C — S — C —O —R Il Il S O in which R stands for a preferably lower, optionally substituted alkyl radical. Considered publications:
German publication No. 1017405. © 209 747/31 & 12.