DE1093137B - Systemic fungicides - Google Patents

Description

GERMAN

It has been found that pentachloroglutaric acid or its sodium salt is an excellent systemic fungicidal Effect in plants, e.g. B. against powdery mildew.

Numerous attempts have been made in the past to develop systemic fungicides. In most cases, the effective agents failed because of the simultaneous fungicidal effect occurring plant damage. Therefore, no such means have come into practice so far.

The agents to be used according to the invention now allow the treated ones to be spared as much as possible Plants are an economical means of combating powdery mildew, in which case it is also very advantageous that the funds are absorbed by both the leaf and the root, creating a beneficial one Application in practice is possible. Pentachloroglutaric acid shows an excellent effect here or its sodium salt, as can be seen from the following examples.

The substances can be obtained by the methods described in the literature, with pentachloroglutaric acid obtained from resorcinol according to Zincke and co-workers (Ber. d. dtsch. former Ges., 25, p. 2219 [1892]) can be.

British patent 664 339 describes fungicidal wrapping papers which contain dialkyl dichlorosuccinic acid esters as the active substance contain. In contrast, according to the invention, systemic fungicides are used for control used by powdery mildew in particular. So there are phytopathogenic fungi on systemic basis Fights ways, d. That is, the agents work through the flow of sap from the plant. This makes it possible for the plants to keep infestation-free for a certain period of time. The subject of the above-mentioned patent specification touches therefore not the subject of the invention.

example 1

Normal humus-rich garden soil was good with 200, ISO, 100 and 50 mg pentachloroglutaric acid per kg soil mixed. In this treated soil, wheat was grown. 14 days after the emergence of the Wheat heavily infected with a spore suspension of wheat powdery mildew and after the outbreak of the disease assess the effectiveness of the preparation.

The result is shown in Table I. From it it follows that the powdery mildew infestation of the wheat despite severe infection by treatment with pentachloroglutaric acid has led to a considerable reduction.

From this experiment it must be concluded that pentachloroglutaric acid was taken up via the roots and is transported into the leaf and has an adverse effect on powdery mildew here.

Systemic fungicides

Applicant:

Farbwerke Hoechst Aktiengesellschaft

formerly Master Lucius & Brüning,

Frankfurt / M., Brüningstr. 45

Dr. Otto Scherer, Dr. Heinz Frensch,

Frankfurt / M. -Maximum,

and Dr. Kurt Härtel, Hofheim (Taunus),

have been named as inventors

Table I.

at . . Powdery mildew infestation in% 100 ' Earth preparation 200 .. mg of active ingredient per kg 50 150 33 Pentachlor 12th 100 62 glutaric acid 100 26th 100 Untreated ... 100

Example 2

Normal garden soil was mixed with 200, 150, 100 and 50 mg of sodium pentachloro-glutarate per kg of soil, and in the soil thus treated, wheat was grown, which 14 days after emergence with a Conidia suspension was severely infected by wheat powdery mildew.

As can be seen from the result of Table II, treatment of the soil with pentachloroglutaric acid also occurs Sodium significantly reduces powdery mildew in wheat.

This experiment shows that pentachloroglutaric acid Sodium is absorbed by the root and passed on to the leaf tissue, where it is resistant to powdery mildew Effect unfolds.

Table II

at .. Powdery mildew infestation in% 100 Earth preparation 200 .. mg of active ingredient per kg 50 150 Pentachlor 21 glutaric acid 12th 100 21 sodium 100 17th 100 Untreated ... 100

009 648/391

Example 3

In the three-leaf stage, wheat was severely infected with a spore suspension of wheat powdery mildew and for 3 days then with sodium pentachloroglutarate in application concentrations of 0.25, 0.125 and 0.06% - based on active ingredient - treated. Wetting sulfur served as a comparison agent in the same application concentrations - based on sulfur as the active ingredient. The test result can be seen in the table below. From it it follows that pentachlorglutaric acid Sodium also has a better effect on leaf treatment than network sulfur and the latter above all in the long-term effect significantly exceeds.

at Table III 0.06% Active ingredient 18th
29 Infestation intensity 6 weeks after
Outbreak of infestation in value figures
1 to 5 *)
at application concentrations of 0.125% 1
3 2
4th 0.06 »/ ₀ preparation 0.25 % Infestation compared to
Untreated = 100
Application concentrations of 100 0.25% Active ingredient 5 5 V ₀ I 0.125 · /. 2
4-5 11
23 13th
24 5 Sodium pentachloroglutarate
Network sulfur 100 100 Untreated

*) The numerals mean:

1 = very light infestation.

2 = slight infestation.

3 = moderate infestation.

4 = severe infestation.

5 = total infestation.

Claims (1)

Claim: Systemic fungicidal agents, especially for combating powdery mildew, characterized by their content of pentachloroglutaric acid or its sodium salt as an active ingredient. Considered publications:
British Patent No. 664,339. © 009 648/391 11.60