DD140412B1 - FUNGICIDAL AGENT FOR CONTROLLING GENUINE FLOUR MUSHROOMS - Google Patents

Description

I II

containing at least 15% of Il.

2. Composition according to item 1, characterized in that such a quantitative composition is applied, as it inevitably results from the reaction of a resulting in the production of propylene oxide 2,2'-dichlorodipropyl ether mixture with n-dodecylamine.

Field of application of the invention

The invention is used in agriculture for controlling powdery mildew diseases, mainly in cereal crops.

Characteristic of the known technical solutions

It is known that long-chain N-alkylmorpholines have fungicidal properties and are used especially for controlling powdery mildew fungi. The long-chain N-alkyl radical may be straight or branched and the C atoms in the ring of morpholine may optionally be substituted by methyl or other alkyl radicals having 1-2 carbon atoms. According to literature and patent data, the 2,6-position is preferred in terms of fungicidal properties. Of the alkyl radicals C ₁₂ -C ₁₈ , a branched C _1-3 radical is apparently to occupy a special position. By contrast, phytotoxic side effects should already be able to occur, for example, in N- (n-dodecyl) -2,6-dimethylmorpholine at the fungicidal activity concentration, which would jeopardize the practical usefulness (Ang. Chem. 77, 327 (1965)).

Object of the invention

The aim of the invention is to develop from available and inexpensive raw materials an N-alkylmorpholine preparation which combines good fungicidal properties and plant compatibility.

Nature and feature of the invention

The invention is based on the idea that the fungicidal properties and the plant compatibility could possibly be influenced in a favorable manner by changing the isomer composition of an N-alkyldimethylmorpholine. Thus, even when using per se not optimal, but available Fettamingemische by appropriate choice of method to achieve an improvement in the utility properties. The review has shown that N-n-dodecyldimethylmorpholine prepared by various methods actually differs in fungicidal activity and phytotoxicity. Thus, the product prepared from a technical 2,2'-dichlorodiisopropyl ether (containing about 20% of 2,2'-dichloro-i-propyl-n-propyl ether), in contrast to literature references and to a product obtained from propylene oxide, was well effective and not phytotoxic , This fact is evidently explained by the different isomer distribution. An investigation revealed that the N-dodecyl-dimethylmorpholine obtained from the chloro-ether gave an isomer distribution of 2.5 to 2.6 = 22:78, whereas the product obtained from propylene oxide contained only the 2,6-position isomer. It has surprisingly been found in these studies that the N-n-dodecyl ^ .e-dimethylmorpholine, in contrast to literature on the conditions in the i-Tridecylderivat. From the biological findings, it can be deduced that the improved bioactive properties of the position isomer mixture go beyond the purely additive expected effect and are obviously due to a synergism. If the proportion of the 2.5 isomer is at least 15%, the increase of the fungicidal activity and the plant compatibility is maintained

 After elucidation of the stated relationships, the solution of the object of the invention is to be characterized by the

- 2 - 207 402

Application of the 2,2'-dichloro-dipropyl ether technical mixture to deliberately alter the isomeric composition of N-n-dodecyldimethylmorpholine. This achieves an advantageous improvement in the use properties (increase in the fungicidal action and plant tolerance). At the same time, it is of particular use that 2,2'-dichlorodipropyl ether is available inexpensively and in large quantities as an undesired by-product of the production of propylene oxide.

Exemplary embodiments Example 1

Barley plants grown in test vessels were sprayed in an aqueous emulsion at a height of about 15 cm with the composition according to the invention which had been formulated as an emulsion concentrate with 75% active ingredient. After the spray coating had dried on, the plants were inoculated with conidia of the powdery mildew of the barley (Erysiphe graminis) and then incubated at temperatures and relative humidity which are favorable for the development of the disease. 10 days after the application, the disease development was evaluated. In the following table, disease infestation and plant tolerance of different use concentrations (relative to the active substance) are shown in comparison to known active substances:

No.

active substance

0.015%

0.03%

1. N- (n-dodecyl) -2,5-dimethylmorpholine

2. N- (n-dodecyl) -2,6-dimethylmorpholine

3. 1. + 2. (15+ 85 parts)

4. 1. + 2. (75 + 25 parts)

olole + olol

0 = no infestation

1 = total infestation

- = completely plant compatible + = significant leaf damage

Example 2:

In the spore germ inhibition test, the fungicidal activity against Botrytis cinerea and Aspergillus niger was tested. The drug and spore suspensions were incubated together in different concentration gradings. After 20 hours incubation at 24 ° C, the germinated and non-germinated spores were counted. Subsequently, the ED ₅₀ and ED ₉₅ values were determined graphically, which are shown in the following table:

Active ingredient no.

Botrytis ED ₅₀

cinerea ED ₉₅

Aspergillus ED ₅₀

mger ED ₉₆

0.0045% 0.01 ... 0.1% 0.0074% 0.0051%

0.0048% 0.01 ... 0.1% 0.015% 0.0076%

0.0028% 0.01 ... 0.1% 0.0068% 0.0038%

0.013% 0.1% 0.021% 0.015%

Claims (1)

-1- 207 402 Claims: 1. Fungicidal agent for controlling powdery mildew fungi based on N-alkyldimethylmorpholines, characterized in that it contains, in addition to the customary formulation auxiliaries, a mixture of positionally isomeric compounds - CH ₂ CH- CH ₂ У - ^C 12 ^H 25 ^{Cn) 0} C ^ CB ₂ - CH