SU534172A3 - Herbicide - Google Patents

Description

(54) HERBICID MEANS

The invention relates to chemical means of weed control in crops of cultivated crops, namely to means based on derivatives of thionophosphoric acid.

A number of compounds are known — thiophosphoric acid esters of amide having herbicidal activity. For example, herbicidal agents containing O-alkyl-O-2nitpo-4-alkyl-phenyl-N - isopropylamidothiophosphate or 0-alkyl-O-2-nitrophenyl-N-isopropylamidothiophosphate as acting.

However, the well-known germicidal agents of this group are not effective enough.

The aim of the invention is a new herbicidal agent based on the efnroamidov thionphosphoria kdislot.

This goal is achieved by the use of compounds of general formula (I) as the active substance in the proposed herbicidal agent.

Noz

X is hydrogen or methyl;

moreover, the content of the active substance in the germicidal agent is in the range from 2 to 80 weight. %

In addition to the active ingredient of general formula (I), the herbicidal agent according to the invention contains auxiliary components FROM the number of solvents, fillers, emulsifiers, dispersants, etc.

The usual forms of application are solutions, emulsions, powders, pastes, granules, etc. They are prepared by well known sposbbs.

The proposed herbicidal agent is selective. Effectively suppressed the growth of weeds, it does not harm such cultivated plants as rice, radish, soybeans, beans, carrots and cotton.

The method of producing compounds of general formula (I) is based on the reaction of ether amide hydrochlorothiophosphates with the corresponding 2-nitro-5-: methylphenols in the presence of a hydrogen chloride acceptor.

Table 1

In Voye examples, having tested compounds of general form (I) for herbicidal activity, for comparison, well-known compounds with germicidal activity are used:

O-methyl - O-2,4-dichlorophenyl - N - isopropylamidothiophosphate (compound L) and 0-methyl-O2-nitrophenyl - N - isopropylamidothiophosphate (compound B).

Example I. Seeds of experimental plants are sown in flower pods and cover the seeds with soil. Thereafter, the soil is treated with compounds according to the invention in the form of emulsifiable concentrates. 20 days after the treatment, the herbicidal effect is evaluated on a five-point scale: O means no damage, 5 is full of plant death.

The results of the experiment are presented in table. 2 (numbers of compounds correspond to the numbers in table 1).

table 2

Example 2. The soil from a paddy field in an amount of 1.5 kg is placed in Ba.gner pots with a diameter of 14 cm and brought to the state of a rice floor. After that, rice seedlings are planted in the pots and the development stage of three leaves, then the millet family is sown, covered with soil and continued. 2

t t in the greenhouse. On the second day after sowing, the following are applied to the soil covered with water. 3 numbers of compounds.

After 25 days, the herbicidal effect is determined on a 5-point scale and phytotoxicity with respect to rice plants. The results are shown in Table. 3

Table 3

Claims (1)

Invention Formula A germicidal agent containing an active ingredient and an auxiliary component selected from the group of solution-itel, a filler, an emulsifier, a dispersant, characterized in that, in order to enhance the herbicide activity, the compounds of the general formula are used as an active ingredient. ) -v Rjnh. ;: p-ocheo  I CHs ten where RI - and l kil R2 - alkyl X - hydrogen. or methyl; ft-1-3; moreover, the content of the active substance in the herbicidal agent is taken from 2 to 80 wt. % Priority signs: 25.09.70 when RI is propyl or isopropyl; X is hydrogen; 2: 5.12.70 with RI-alkyl Sz- € 4; X is methyl; n 1-3.