RU2468580C2 - Agent for pre-sowing treatment of wheat seeds - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention relates to agriculture. An agent for pre-sowing treatment of wheat seeds represents a substance close in structure to natural phytohormones of auxin system. It includes a benzimidazole or a benzoxazole fragment and has the structure

, where R=Ph, X=NH, or R=Tol, X=NH, or R=Ph, X=O, or R=Tol, X=O.

EFFECT: invention makes it possible to increase productivity due to increased speed of root and coleoptile growth in wheat seeds.

5 tbl, 5 ex

Description

The invention relates to the creation of new growth-promoting compounds of the benzimidazole and benzoxazole series, similar in structure to natural phytohormones that can be used in agriculture to improve the sowing qualities of wheat seeds.

Known growth-regulating activity of such synthetic plant growth and development stimulants as compounds of the thiazolidine series - 5-substituted 2-thiothiazolidin-4-ones on sunflower and wheat plants along the length of the seedling (Ginak A.I., Suleimankadiev S.E., Suleimankadieva A. E. Growth-regulating activity of 5-substituted 2-thiothiosolidin-4-ones // Agrochemistry. 2007. No. 5. S. 49-52). Of the tested compounds, only two showed an average activity, the rest of the substances practically did not possess it, which cannot speak of the promise of this class of compounds.

Among the derivatives of urea, substances exhibiting growth-regulating activity are also known. For example, thidiazuron (N-phenyl-N'-1,2,3-thiadiazol-5-yl-urea) shows a unique combination of properties characteristic of auxin and cytokinin (Murthy BNS, Murch SJ, Saxena PK Thidiazuron: A Potent regulator of in vitro plant morphogenesis // In Vitro Cell. Dev. Biol. Plant. 1998. V.34. P.267-275). However, in some cases, it can induce inhibition of plant enzymes and, thus, give the opposite effect, and also with an increased content of heavy metals in the soil, it contributes to their accumulation in plant tissues.

It was noted that pyrrolidones and amides of carboxylic acids are of interest as physiologically active substances (Muzychenko G.F., Nenko NI, Burlaka S.D., Sibiryakova M.A., Kopan A.S. Efficiency of new 4-NX derivatives -aminopyrrolidones-2 with growth-regulating and anti-stress activity // Agrochemistry. 2005. No. 5. S. 71-75). It is possible to use 1- (4-nitrophenyl) -4-N-ethylaminopyrrolidone-2 and 1- (4-nitrophenyl) -4-N-butylaminopyrrolidone-2 as growth regulators to improve the sowing qualities of Pobeda-50 winter wheat seeds, and also 3-N-phenylamino-4-amino (4-nitrophenyl) -butanoic acid N-phenylamide to activate the germination of seeds of winter wheat cultivar Nika Kuban and increase plant productivity. However, these compounds are far from natural phytohormones in structure and also have low solubility in water, which limits their use.

The closest substance in structure and action is 6-sulfophenyl-4-oxo-3-oxa-6-azabicyclo [3.1.0] hexane (Tyukhteneva Z.I., Badovskaya L.A., Nenko N.I. / RF Patent No. 2409580), however, along with limited solubility in water, it shows insufficient activity not exceeding 14.3%.

The objective of the invention is to create on the basis of readily available starting compounds of a number of growth-promoting agents.

The technical result consists in increasing the productivity of crops by increasing the growth rate of roots and coleoptiles of wheat seeds.

The claimed technical result is achieved through the use of a substance similar in structure to the natural phytohormones of the auxin series, including a benzimidazole or benzoxazole fragment and having a structure

,

,

where 1: R = Ph, X = NH, or

2: R = Tol, X = NH, or

3: R = Ph, X = O, or

4: R = Tol, X = O,

for presowing treatment of wheat seeds.

The basis was taken 4-oxoalkanoic acids and aromatic binucleophiles - 1,2-phenylenediamine (Acros Orgauics, Belgium) and 2-aminophenol (Merck, Germany). The reaction was carried out in an environment of aprotic solvents (benzene or toluene) with continuous azeotropic distillation of the released water.

The preparation of new compounds and their laboratory tests of growth-regulating activity are illustrated by the following examples.

Example 1. One-step synthesis of 3a-phenyl-2,3,3a, 4-tetrahydro-1H-benzo [d] pyrrolo [1,2-a] imidazol-1-one 1:

2 g (11 mmol) of β-benzoylpropionic acid and 1.2 g (11 mmol) of 1,2-phenylenediamine were heated in 30 ml of absolute benzene with continuous azeotropic distillation of the liberated water for 5 hours. The precipitate was washed with benzene, then with hexane, and recrystallized from acetone. Yield 2.12 g (75%), pale yellow crystals, _mp 156-159 ° C. IR spectrum, cm ^-1 : 3330 (NH), 1710 (C = O, Amide-I), 1320 (-CN-). ¹ H NMR spectrum, ppm: 6.50-6.90 m (4H, arom.), 7.25-7.60 m (5H, Ph, arom.), 2.35-2.60 m (2H, -C ₃ H ₂ -, pyrrolidine), 2.70-2.90 m (2H, -C ₂ H ₂ -, pyrrolidine), 4.38 s (NH, 1H). Found,%: C 76.56; H 5.73; N, 11.56. C ₁₆ H ₁₄ N ₂ O. Calculated,%: C 76.80; H 5.60; N, 11.20. Compounds 2-4 were obtained similarly.

Example 2. One-step synthesis of 3- (4-methylphenyl) -2,3,3a, 4-tetrahydro-1H-benzo [d] pyrrolo [1,2-a] imidazol-1-one 2:

1.76 g (11 mmol) of 4- (4-methylphenyl) -4-oxobutanoic acid and 1.2 g (11 mmol) of 1,2-phenylenediamine were taken for the reaction. Yield: 1.98 g (78%), pale yellow crystals, _mp 158-160 ° C. IR spectrum, ν, cm ^-1 : 1330 (CN), 1690 (C = O, Amide-I), 3350 (NH). ¹ H NMR spectrum, δ, ppm: 2.25 s (3H, CH ₃ ), 2.40-2.55 m (2H, C ₃ H ₂ , pyrrolidine), 2.50-2.70 m (2H, C ₂ H ₂ , pyrrolidine) 4.35 s (NH, 1H), 6.50-6.85 m (4H, arom.), 7.15-7.35 dd. (4H, arom.). Found,%: C 76.16; H, 6.15; N 10.10. C ₁₇ H ₁₆ N ₂ O. Calculated. %: C 75.69; H 6.06; N, 10.61.

Example 3. One-stage synthesis of 3a-phenyl-3,3a-dihydrobenzo [d] pyrrolo [2,1-b] oxazole-1 (2H) -one 3:

For the reaction, 2 g (11 mmol) of β-benzoylpropionic acid and 1.2 g (11 mmol) of 2-aminophenol were taken. Yield 1.71 g (62%), yellow crystals, _mp 153-155 ° C. IR spectrum, ν , cm ^-1: 1326 (CN), 1710 (C = O, «amide-I») ¹ H NMR, δ, ppm .: 2.18-2.35 m (2H, C ₃ H _2, pyrrolidine). 2.30-2.48 m (2Н, C ₂ H ₂ , pyrrolidine), 6.50-6.90 m (4Н, arom.), 7.10-7.30 m (5Н, Ph, arom.). Found,%: С 76.10; Н 4.98; N 5.12. C ₁₆ H ₁₃ NO _2. Calculated,%: C 76.49; H 5.18; N5.58.

Example 4. One-step synthesis of 3- (4-methylphenyl) -3,3a-dihydrobenzo [d] pyrrolo [2,1-b] oxazole-1 (2H) -one 4:

1.76 g (11 mmol) of 4- (4-methylphenyl) -4-oxobutanoic acid and 1.2 g (11 mmol) of 2-aminophenol were taken for the reaction. Yield 2.27 g (78%), greenish-yellow crystals, _mp 116-117 ° C. IR spectrum, ν, cm ^-1 : 1325 (CN), 1700 (С = O, "Amid-I"). ¹ H NMR, δ, ppm .: 2.29-2.50 m (2H, C ₃ H _2, pyrrolidine), 2.45-2.65 m (2H, C ₂ H _2, pyrrolidine), 2.60 (3 H, R, CH ₃ ), 6.39-6.85 m (4H, arom.), 7.10-7.45 d.d. (4H, arom.). Found,%: C 77.20; H 5.41; N 5.09. C ₁₇ H ₁₅ NO ₂ . Calculated,%: C 76.98; H 5.66; N, 5.28.

Example 5. Laboratory biological tests of the claimed growth-stimulating agents.

For laboratory experiments, seeds of soft spring wheat Triticum aestivum L. cultivar Saratovskaya, 29 generations of 2008, were selected. Before sterilization, a selection was made of complete, without visible signs of any diseases of wheat grains. The selected seeds for 5-10 minutes with shaking were treated with a detergent to remove hydrophobic contaminants that interfered with uniform wetting of the surface of the seeds with the studied compounds, then they were washed with distilled water. Wheat grains were placed for 1.5 hours in solutions of substances 1-4 with concentrations representing a series of double dilutions.

Stock solutions of the substances were prepared as follows: the substances were previously dissolved in a small amount of alcohol, then the volume of the solution was adjusted to 100 ml in volumetric flasks with distilled water. The maximum concentration of the substance was limited by its solubility in alcohol, as well as the maximum permissible concentration of the alcohol itself, which does not affect the growth and germination of wheat seeds (no more than 2-3% alcohol in water). Then the remaining solutions were prepared by successive two-fold dilution of the stock solution and the resulting solutions. The prepared concentrations of the substances are presented in table 1.

Table 1 Designation of tested substance concentrations In Concentrations, mol / l one 2 3 four 5 6 7 8 9 10 one 2 × 10 ^-4 5 × 10 ^-4 1 × 10 ^-3 2 × 10 ^-3 4 × 10 ^-3 8 × 10 ^-3 2 × 10 ^-2 3 × 10 ^-2 6 × 10 ^-2 1 × 10 ^-1 2 4 × 10 ^-7 8 × 10 ^-7 2 × 10 ^-6 3 × 10 ^-6 6 × 10 ^-6 1 × 10 ^-5 3 × 10 ^-5 5 × 10 ^-5 1 × 10 ^-4 2 × 10 ^-4 3 7 × 10 ^-6 1 × 10 ^-5 3 × 10 ^-5 6 × 10 ^-5 2 × 10 ^-4 2 × 10 ^-4 5 × 10 ^-4 1 × 10 ^-3 2 × 10 ^-3 4 × 10 ^-3 four 8 × 10 ^-6 2 × 10 ^-5 3 × 10 ^-5 6 × 10 ^-5 1 × 10 ^-4 3 × 10 ^-4 5 × 10 ^-4 1 × 10 ^-3 2 × 10 ^-3 4 × 10 ^-3

Germination of seeds was carried out in Petri dishes on wet filter paper for 3 days in a dark place at a temperature of 25 ° C. The control was seeds germinated in distilled water, as well as in solutions of 3-indolylacetic acid (IAA). IAA concentrations were 10 ^-3 , 10 ^-5 and 10 ^-7 g / l. Fluka IAA with a purity> 98% was used as a standard.

The growth-promoting effect of the substance was evaluated by such quantitative indicators as the average length of the roots and coleoptiles of seedlings in relation to the control, as well as by the total number of germinated seeds. Each experiment was carried out in triplicate, in each repetition of 20 seeds. The results were subjected to statistical processing. The confidence probability was taken equal to 0.95.

The highest activity among the compounds studied by us in stimulating root growth was shown to contain compound 1 (from 20.1% to 43.7% relative to the control) containing a benzimidazole fragment and a phenyl substituent in the 5th position in the concentration range from 2 × 10 ^-4 to 1 × 10 ^-1 mol / L (table 2). The growth-promoting activity of this compound is also observed for coleoptiles of wheat (7.9–11.7%) at the same concentrations (Table 3). The maximum number of germinated seeds was observed at a concentration of 1 × 10 ^-3 , as well as in the range of 2 × 10 ^-2 -6 × 10 ^-2 mol / l (Table 4).

When a 4-methylphenyl substituent is introduced into the 5th position, a slight decrease in growth-promoting activity is observed both in relation to the roots and in relation to coleoptiles. So, substance 2 in the entire range of the studied concentrations showed a more moderate activity in stimulating root growth (by 9.4-23.4% relative to the control). At the same time, compound 2 shows a positive effect on the total germination of seeds - the number of germinated seeds treated with this substance increased compared with the control (107-136%) (Table 4).

Compound 3, an oxygen-containing structural analogue 1, had a positive effect (12.7–25.3%) on the length of the roots of wheat (Table 2). At the same time, stimulation of the growth of coleoptiles of plants was noted at the level of 11.0-19.2% compared with the control (Table 3).

Compound 4, which has a 4-methylphenyl substituent in the 5th position, exhibits a more moderate stimulating effect on root growth (3.1-10.6%) and practically does not affect the growth of colioptiles.

Table 4 The number of sprouted seeds treated with solutions In The number of seeds,% Options one 2 3 four 5 6 7 8 9 10 one 81 78 106 81 81 81 94 one hundred 94 fifty 2 136 one hundred 114 one hundred 129 one hundred 114 114 107 71 3 one hundred 93 93 114 93 121 79 93 one hundred 79 four 82 94 94 88 106 94 one hundred 82 71 88

When compared with the control (water) of IAA activity, it was found that it has the most pronounced growth-stimulating effect at a concentration of 10 ^-5 g / l. The increase in root lengths was ~ 21%, and coleoptiles ~ 16% of the control (Table 5).

Table 5 The effect of various concentrations of IAA on the length of the roots and coleoptiles of three-day-old wheat seedlings as a percentage relative to the control (water) Substance Length,% of control The roots Coleoptiles Water 0 0 IAA (10 ^-3 g / l) -28.8 -6.1 IAA (10 ^-5 g / l) 20.7 15,5 IAA (10 ^-7 g / l) 6.1 10.9

Claims (1)

A presowing treatment of wheat seeds, which is a substance that is close in structure to natural phytohormones of the auxin series, including a benzimidazole or benzoxazole fragment and having a structure

,
where R is Ph, X is NH, or
R is Tol, X is NH, or
R is Ph, X is O, or
R - Tol, X - O.