CS238548B1 - Growth Regulator of Agricultural Crops and Horticulture Cultures - Google Patents

Abstract

The plant growth regulator stimulating tillering and branching of agricultural crops and horticultural crops contains as an active ingredient RB-(m-hydroxybenzyl) adenosine or its derivative ΠP-fm-hydroxybenzyl) adenine in a concentration of 10-7 to 10-3 mol per liter of liquid carrier. The new regulator exhibits high cytokinin activity and allows application by spraying. Its use is considered in particular in increasing tillering of cereals, increasing the supply of assimilates to grains, increasing the branching of agricultural crops and horticultural crops grown for the production of flowers, seeds and cuttings.

Description

The invention relates to a plant growth regulator which stimulates the propagation and branching of agricultural crops and horticultural crops.

Increasing the branching of cereals and branching of horticultural crops by exogenous application of plant growth regulators has so far been based primarily on growth retardation. This intervention disturbs the correlation between organs and indirectly stimulates the growth of lateral buds. To this end, growth retardants are used which inhibit the synthesis of natural gibberellins, e.g. 2-chloroethyltrimethylammonium chloride and 2,2-dimethylhydrazide of succinic acid, or increase the formation of ethylene, e.g. 2-chloroethylphosphonic acid. In addition, agents affecting apical dominance are used, in particular by affecting auxin transport. The disadvantages of the practical use of these substances lie in their indirect action, ie. they often exhibit growing undesirable side effects, such as limiting long-term growth and reducing mass formation after application of agents inhibiting the production of gibberellins, inhibiting root growth and cell division following exposure to ethylene releasing agents, or disrupting the geotropic and phototropic bends of plants after application of substances disrupting auxin transport.

These drawbacks are overcome by the application of cytokinin-like growth regulators. The stimulatory effect of cytokinins on the propagation and branching of intact plants exert their effects on suppressing apical dominance, inducing differentiation of advent buds and disrupting the bud growth period.

These properties of cytokinins have already been practically used in stimulating the branching and branching of plants on an experimental scale and

238 548 for example in apple, pea, citrus and other horticultural and fruit crops.

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N -benzyladenine, hereinafter referred to as bzl Ade, applied by dressing to the roots of spring barley. Increased grain production in young spikes was achieved, grain equilibrium was increased both between spikes and within the cob. The main drawback of the cytokinins used hitherto is their relatively low spray application efficiency. Their low water solubility makes it impossible to apply them at higher concentrations and reduces the operability of their use.

These drawbacks are overcome by the novel plant growth regulator stimulating the propagation and branching of agricultural crops and horticultural crops according to the invention, characterized in that the active θ component is N- (m-hydroxybenzyl) adenosine, hereinafter referred to as 6 6 m-OH-bzl Ado or derivative of N - (m-hydroxybenzyl) adenine, "hereinafter referred to 7 m -3-OH-Bzl-Ade in a concentration of 10 to 10 mol l" ¹ of the liquid carrier. These substances exhibit 6-fold greater biological activity than the bzl Ade used in practice, as determined by a bioassay based on stimulation of cell division in tobacco tissue culture, and are as active as the most active natural cytokinin trans-zeatin.

Examples of the use of the growth regulator according to the invention are given below.

Example 1- Increasing the production of cuttings by poinsettia with N - (m-hydroxybenzyl) adenosine.

A growth regulator was prepared by adding 7 g of hydroxylamine hydrochloride and 10 g of triethylamine to a solution of 12 g of m-hydroxybenzaldehyde in 100 ml of ethanol and refluxing for 3 hours. It was then concentrated to crystallize. 12.4 g of m-hydroxybenzaldehyde oxime were obtained. To a solution of 14 g of oxime in 100 mL of ethanol was added 1 g of a palladium catalyst and the solution was hydrogenated under 2 atm. After 5 hours, 10 g of m-hydrobenzylamine was obtained. To a solution of 6 g of m-hydroxybenzylamine in 100 ml of ethanol was added 14 g of chlorpurine riboside in 5 g of triethylamine. The reaction mixture was heated to boiling for 3 hours under stirring

238 548 reflux condenser. It was then evaporated in vacuo and the residue no

was crystallized from ethanol. 15 c of N- (m-hydroxybenzyl) adenosine were obtained.

In the vegetation experiments, the growth regulator m-OH-bzl ° Ado was compared with the standard cytokinin bzl Ade.

θ

Due to the low solubility of bzl Ade in water, the same procedure as for bzl ^for Ade was maintained when dissolving both substances ₍ although m-OH-bzl Ado could be dissolved directly in water at the concentrations used). Dissolve in 1 ml of 1 N hydrochloric acid, dilute with water, adjust the pH of the solution to 5.8 with 1 N sodium hydroxide solution, add a wetting agent and make up the volume to 1 liter

The growth regulator m-OH-bzl ° Ado has been practically tried to increase the formation of lateral shoots used to cut in the nursery poinsettia, Euphorbia pulcherima Willd. cv. Annette Hegg, On maternal plants introduced into the mother plant in mid-January, m-OH-bzl Ado and comparative 'standard' · cytokinin bzl Ade were sprayed at concentrations of 10 “, 10 a and 10 mol mol l four times from 14 April at 14 daily intervals. The harvested cuttings were treated with an auxin stimulator and placed in multiplicity. In experiments, the number of rooted cuttings, ie, pieces per mother plant and their rooting, ie% of rooted cuttings from the total number, was monitored. The results are shown in Table 1,

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Tab.l. Comparison of the influence of m-OH-bzl Ado and standard bzl Ade on the production of cuttings by the mother plants of poinsettia.

The number of cuttings from 1 parent plant was indicated.

Substance Mole concentration l · ¹ · —————— 2 ——______— i2Z -—___ i2 ™ -___ i2Z -___— m-0H-bzl ⁶ Ado 53.8 63.2 65.6 89.3 bzl ⁶ Ade 53.8 62.3 65.3 76.8

Compared to the 100% control, the maximum increase in cuttings production after application was achieved

4 i m-0H-bzl ^D Ado at a concentration of 10 ”mol l“, ie 1666%, while bzl Ade was less effective «142%, concentrations of both substances higher —4 —1 than 10 mol 1 were effective but toxic . The application of both growth regulators did not affect the rooting of cuttings.

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Plants obtained from cuttings from mother plants treated with both growth regulators produced a greater number of side shoots, which favorably affected their quality.

Example 2

Increasing the production of gerberas by 6

N - (m-hydroxybenzyl) adenosine.

The m-OH-bzl growth regulator Ado was prepared and dissolved in the same manner as described in Example 1. It was practically tested in increasing the shoot formation used in the Gerber, Gerbera jamensonii Bolus ex Hook cv. Hellios. The regulator was compared to the standard cytokinin bzl ^ Ade.

The roots used to establish the mother plant were soaked with the basal part before planting on 15 February. cutting surface + approx

cm adjacent part of the root, in solution m-OH-bzl Ado, respectively.

bzl Ade, for 15 min. Both growth regulators were further applied by spraying after the 1st and 2nd cuttings. The harvested cuttings were treated with an auxin stimulator and placed in a multiplier. In the experiment the number of cuttings was monitored. pieces per mother plant and their rooting, ie,% of rooted cuttings out of the total. The results are shown in Table 2.

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Table 2, Comparison of the influence of m-OH-bzl Ado and standard bzl Ade on the production of cuttings by the mother gerbera plants. The number of cuttings from 1 nest of parent plants was given.

Substance 0 Concentration as 10- ⁶ mol l ¹ ΙΟ ^{5 5} 10 ⁴ m-0H-bzl ⁶ Ado 16.5 19.2 20.0 22.8 bzl ^ Ade 16.5 18.5 20.3 16.2

Compared to the control, i.e. 100% were achieved maximum increase in the number of cuttings after m-OH Bzl Ado concentration of 10 1 _t moles i.e. 138% even in this case the ^six Bzl Ade less efficient, i.e. The application of both growth regulators did not affect the rooting of the harvested cuttings.

238 548

Example 3. Increasing the production of poinsettia cuttings by action

N - (m-hydroxybenzyl) adenine f

The m-OH-bzl Ade growth regulator was prepared in an analogous manner 6 to the m-OH-bzl Ado as shown in Example 1. Only the chlorpurine riboside was replaced by chlorpurine. The experiments were performed in the same manner as in Example 1 _t θ '6. except that m-OH-bzl Ade was used instead of m-OH-bzl Ado. Practically the same results as in Table 1 were achieved,

Example 4 * Increasing the production of gerberas cuttings with N - (m-hydroxybenzyl) adenine

The m-OH-bzl Ade growth regulator was prepared by an analogous 6 procedure to the m-OH-bzl Ado as shown in Example 1. Only the chlorpurine riboside was replaced with chlorpurine. The experiments were arranged in the same manner as in Example 2 except that that

6 instead of m-OH-bzl Ado, m-OH-bzl Ade was used. Virtually the same results as shown in Table 2 were obtained.

Further use of both plant growth regulators according to the invention is possible. Both compounds exhibit potent cytokinin-specific effects. They can therefore be used to increase the offsets of cereals, control the assimilation of the assimilate to the caryopses, suppress media dominance in the hair, thereby increasing grain production and promoting a balanced grain development. Furthermore, they can be used to increase the formation of flower stems in crops and crops grown for flowers, e.g. chrysanthemums, poinsettia etc. and seeds, eg oilseed rape, peanuts etc., including seed crops, especially biennials, e.g. beet, various vegetables, etc. They can also be used to increase the resistance of plants to stress, increase chlorophyll formation and slow down the aging of the plant by increasing their productivity and prolonging the shelf life of harvested organs. They can also be used to stimulate bud and shoot formation in explanted tissues and tissue cultures, i.e., in vitro propagation of plants.

Claims (3)

SUBJECT OF THE INVENTION 238 548 Plant growth regulator stimulating the offshooting and branching of agricultural crops and horticultural crops, characterized by: the active ingredient is N - (m-hydroxybenzyl) adenosine, or its 6-7 N (m-hydroxybenzyl) adenine derivative at a concentration of 10-7 10 mol per liter of liquid carrier.