ZA200103385B

ZA200103385B - Use of useful substances to promote the growth and health of plants.

Info

Publication number: ZA200103385B
Application number: ZA200103385A
Authority: ZA
Inventors: Bettina Kopp-Holtwiesche; Johann-Friedrich Fues; Richard A Sikora; Johannes Hallmann; Doris Bell; Stephan Von Tapavicza; Ralf-Peter Schuster
Original assignee: Cognis Deutschland Gmbh
Priority date: 1998-10-26
Filing date: 2001-04-25
Publication date: 2002-07-25
Also published as: EP1124420A1; AR020940A1; CN1328418A; CO5231141A1; AU1039900A; DE19849253A1; WO2000024255A1; JP2002528396A; ID29588A; CA2348951A1; BR9914802A; HK1039438A1; KR20010080331A

Description

Henkel KGaA

Dr. Fues/Q 25.10.98

Patent Application

H 3695

Improved nutrient mixtures for promoting plant growth and plant health

The technical teaching described below relates to the field of the promotion of healthy plant growth. The teaching according to the invention : is intended especially to support and encourage the natural interaction between two factors, namely on the one hand promotion of plant growth and strengthening of the resistance of plants to pathogens, particularly those responsible for fungal, bacterial and/or viral diseases, but also sucking pests, on the root and/or aerial parts of the plants. A further object of the invention is to be able to use, as nutrients or nutrient mixtures for achieving this object, components which are at least substantially based on natural substances and which do not additionally contaminate the working area in question. This applies both to the soil and plant regions and to the human and animal regions in contact therewith, as well as to the groundwater problem which always has to be taken into account in connection with agricultural processes.

The technical teaching described below thus meets a currently important requirement of the agrobiological and agrochemical process sector, whereby on the one hand it becomes possible to optimise the sought-after eco-industrial results without at the same time having to ignore the economic perspective. Practically all the components of the multicomponent system used in accordance with the invention can take the

H 3695 2 form of chemicals based on natural substances. On the one hand, the source of these components is healthy plant growth; on the other hand, for example, main components formed by marine biology or some other kind of biology are essential constituents of the multicomponent mixtures in terms of the invention. The teaching according to the invention combines natural — bound carbon cycles and utilizes the components isolated therefrom, and appropriate to the demands according to the invention, for plant development and the care of healthy plant growth. It is immediately clear that, precisely in this case of the natural carbon cycle, not only is additional contamination ruled out, positive interventions are also facilitated which can help to moderate and reduce the damage already in existence today.

The teaching of the invention builds on a number of the Applicant's technical developments, some of which form the subject of appropriate publications and some of which form the subject of earlier patent applications. Specific reference will be made to these principles below.

However, the following will be dealt with first:

Subject of the invention

In a first embodiment, the invention relates to the use of multicomponent nutrient mixtures of at least predominantly organic origin for the cultivation and care of useful and ornamental plants by activating the plants’ rhizosphere and/or phylloshpere and hence promoting both plant growth and plant health in combating pathogens, particularly those responsible for fugal, bacterial and/or viral diseases, but also sucking pests, on the root and /or aerial parts of the plants. The nutrient mixtures used according to the invention contain the following essential main components: (a) chitin and/or chitosan of oligomeric and/or polymeric structure, used in combination with (b) ecologically safe surfactant compounds from the class of the alkyl

H 3695 3 (poly) glycosides of the O/W type - hereinafter also referred to as “APG compounds” — and also preferably together with (c) organic compounds which have lipophilic, saturated and/or olefinically unsaturated hydrocarbon radicals with a fatty structure and are both aerobically and anaerobically degradable.

In terms of the act of the invention, the combination of the active substances (a), (b) and, if desired, (c) can be used in a mixture of all the nutrient components with one another, but it is also possible to use at least some of said components at different times. In this last-mentioned case, however, it is necessary to ensure that a sufficient combined action of the sum of all the nutrients can be achieved in the soil and/or the plant. This makes it possible in particular to determine or co-determine the practicable intervals in cases where individual components of the multicomponent mixtures are introduced at different times.

The multicomponent mixtures according to the invention are based on the objective especially of influencing and promoting precisely the growth of plant strengthening microbial populations in the rhizosphere region — i.e. the root region — but also in the phylloshpere region — i.e. on the surface of the aerial part of the plants and particularly in the leaf region.

Accordingly, the teaching according to the invention provides the introduction of the multicomponent mixtures both into the soil region and onto the aerial region of the plants. In principle, these multicomponent mixtures can be used in any forms of presentation optimised to the particular practical requirements. Thus suitable examples are both flowable and especially water-dilutable multicomponent mixtures, but also solid forms of presentation which can be, for example, powders, granules and the like and optionally in encapsulated form.

Details of the teaching according to the invention

Firstly, for a better understanding of the teaching according to the

H 3695 4 invention, a brief summary will be now be given of essential features of the relevant published prior art and the subject of the Applicant's earlier patent applications, already mentioned above, in the field in question.

DE 44 37 313 describes the use of phosphorus-containing and nitrogen-containing components selected from the class of the - phospholipids for improving plant growth. Addition of these phospholipids to the substrate on which the plants are or will be grown improves the growth of these plants. It is suggested that this increase in growth is linked to a stimulation of the microorganisms living in the substrate. Possible phospholipids are primarily lecithin, lecithin hydrolyzates and chemically modified lecithins.

WO 93/01150 describes easy-to-handle fertilizer mixtures for introducing N into plant growth. Together with the mixtures of fertilizers based on macronutrients and micronutrients for plant cultivation, said patent provides the use of water and oil phase in the presence of W/O invert emulsifiers. This is said to assure the formation particularly of pasty mixtures in which the continuous oil phase in the form of a film separates or encloses the aqueous constituents of the mixture. Oils of vegetable origin and mineral oil are listed as equivalent oil phases.

German patent application DE 197 01 127 relates to a low-foaming wetting agent, presented in the form of a highly concentrated but nevertheless flowable and pourable aqueous concentrate based on surfactant, for intensifying the penetration and spreading of water in the region of the plants’ root system when watered, said concentrate containing alkyl (poly) glycoside compounds of the O/W type — hereinafter also referred to as “APG compounds” — as an ecologically safe surfactant component, olefinically unsaturated alcohols as a foam inhibitor/antifoam agent and water-soluble lower alcohols as viscosity regulators.

The technical teaching of the Applicant's earlier patent application

DE 197 48 884.6 on the promotion and care of plant growth by controlling

H 3695 5 the natural growth processes in the substrate is based on the idea primarily of promoting, controlling and assuring microbial growth in the soil by introducing a multicomponent mixture, which is described below. The disclosure of said earlier patent application is also incorporated here with the subject of the disclosure of this invention. The primary promotion of : microbial growth is assured particularly in the rhizosphere region and hence in the region of the substrate through which the plants’ roots pass, this being the decisive region for plant growth. The teaching of said earlier patent application is guided by two ideas of overriding importance:

Together with carriers containing phosphorus (P) and nitrogen (N) and, if desired, other plant macronutrients and/or micronutrients, selected compounds containing hydrocarbon radicals are now introduced into the soil as additional C sources for the growth of the microbial flora. At the same time, the formulation of these growth promoters and their use form allow their optimised spreading in the root region, including their introduction into the rhizosphere region of the substrate. The teaching of said earlier patent application, on which the teaching of the present development is ultimately also based, is accordingly characterized by the introduction of aqueous formulations containing -~ ecologically safe wetting agents of the O/W type, together with — organic compounds which have lipophilic, saturated and/or olefinically unsaturated hydrocarbon radicals with a fatty structure and are both aerobically and anaerobically degradable, as additional C sources for the growth of the microbial flora, coupled with the simultaneous and/or staggered introduction of — P and/or N compounds, at least some of which have lipophilic radicals and which are preferably oil-soluble, and, if desired, carriers containing other macronutrients and/or micronutrients for plant growth.

Even though such a strengthening of the healthy natural microbial flora in the soil and hence in particular of corresponding bacterial strains in

H 3695 6 the rhizosphere region of the growing plant enables positive effects to be achieved in terms of healthy plant growth, the teaching of this invention now provides a further substantial extension of the technical possibilities in precisely this field.

It is known from the relevant published prior art that the concomitant - use of chitin and chitin-based derivatives — especially chitosans in this case — in the agricultural sector makes it possible to achieve substantial improvements which are characterized on the one hand by a strengthening of plant health, but also in particular by an increase in crop yield. From the comprehensive literature, reference may be made, for example, to the publication by Zbigniew S Karnicki et al. entitled “CHITIN WORLD",

Wirtschaftsverlag NW, Verlag fiir neue Wissenschaft GmbH, Bremerhaven,

Germany, 1994. Reference may be made here for example to the section by Henryk Pospieszny et al. entitled “NEW APLICATIONS OF CHITOSAN

IN AGRICULTURE’, loc. cit., pages 246 to 254, and the literature cited therein. Reference may also be made to chapter 8 by Donald Freepons entitled “Enhancing Food Production with Chitosan Seed-Coating

Technology” and to other sections of the same literature reference: chapter 1 by Q. Li et al. entitled “Applications and Properties of

Chitosan”, chapter 2 by Shigehiro Hirano entitled “Applications of Chitin and Chitosan in the Ecological and Environmental Fields” and chapter 11 by Henryk Struszczyk et al. entitled “New Applications of Chitin and

Its Derivatives in Plant Protection”. Finally, reference may be made to the publication by Lee A. Hadwiger et al. entitled “CHITOSAN, A

NATURAL REGULATOR IN PLANT-FUNGAL PATHOGEN

INTERACTIONS, INCREASES CROP YIELDS", Academic Press, Inc. 1984, pages 291 et seq., and to the publication in “Biotechnology Annual

Review Volume 2°, Elsevier Science B.V. 1996, entitled “Chitin biotechnology applications”, edited by SHIGEHIRO HIRANO, loc. cit, pages 237 to 258.

H 3695 7

The literature cited here shows that the chitin bound to natural substances, or derivatives thereof, and especially the chitosan obtained by deacetylation, both in oligomeric form and in polymeric form, exhibit a pronounced activity during plant cultivation in the sense of a marked activity against pathogens, particularly those responsible for fungal, bacterial and/or viral diseases. However, chitin or chitosan-based treatment agents also prove to be effective against sucking pests on the root and/or aerial parts of the plants. The teaching according to the invention utilizes this knowledge of the prior art and combines these components — referred to as active substance class (a) in the definition according to the invention — with the nutrients or nutrient mixtures which are emphasized in the teaching of earlier patent application DE 197 48 884.6 and which are described according to the invention in subclasses (b) — APG compounds of the O/W type — and (c) — compounds which have hydrocarbon radicals with a fatty structure and are both aerobically and anaerobically degradable. Studies on the significance of the individual components of the nutrients or active substances combined according to the invention have shown that combining component (s) (a) - i.e. the chitosan compounds of oligomeric and/or polymeric structure — with the APG compounds of the O/W type already affords substantial increases in efficacy in terms of the objective according to the invention. The principle here is probably the very greatly intensified spreading of nutrient class (a) in the soil structure and hence, in particular, its introduction into the immediate boundary region of the root surface, or, where such nutrient mixtures of components (a) and (b) are applied to the aerial part of the plants, the likewise intensified spreading of the chitosan-based nutrient constituents. This is probably also accompanied by encouragement of the penetration of these nutrient components into the microstructure of the plant cuticle and especially the leaf surface. Of course, the same also applies to the corresponding spreading or distribution of nutrient components (c) concomitantly used

H 3695 8 according to the invention.

In one preferred embodiment, the invention provides, in addition to components (a), (b) and preferably (c), the introduction or application of P and/or N compounds, at least some of which have lipophilic radicals, and, if desired, carriers containing other macronutrients and/or micronutrients for = plant growth, into the region of the plants’ roots and/or to-the-aerial part-of the plants. More evidence of the specific nature of nutrients or nutrient class (d) mentioned here will be given below. Firstly, however, the following clarification will be reiterated:

The essence of the improved technical act in terms of the teaching according to the invention lies in the combination of these nutrient classes (a), (b) and (c) in terms of the teaching according to the invention, preferably with the concomitant use of the nutrients of subclass (d) — P and/or N compounds having lipophilic radicals. Let it be emphasized here yet again that each of the nutrient subclasses in question can be completely and/or substantially based on natural substances and fully undergoes natural degradation by metabolic processes. Chitin and the chitosan compounds derived therefrom are known to be natural substances which are formed for example by marine fauna, especially crabs, crustaceans and similar shellfish, and are obtained as residual substances when these seafoods are commercially exploited. By combining them with the other nutrient classes of the teaching of the invention, which in turn are of vegetable origin, it becomes possible to optimise healthy plant growth without having to resort to synthetic auxiliary substances like fungicides, bactericides, virucides and the like. However, in the manner known to those skilled in the art, the biological synthesis of chitin — and hence the preparation of chitosans in terms of the invention - as part of the cultivation of fungal populations can also be carried out on the industrial scale.

Firstly, detailed information on nutrient components (a), (b), (c) and (d) defined according to the invention will be given below.

H 3695 9 (a) “Chitin and/or chitosan of oligomeric and/or polymeric structure”

It is known that the underlying natural substance source here, chitin, is a high molecular weight compound normally characterized by molecular weights well above 1 million. Chitin-based waste products, especially the shells or crusts of crabs, crustaceans and other organisms of marine fauna, are abundantly available to modern food technology. Various possible methods of exploitation are known; reference may be made to the relevant literature cited above. Exploitation of these waste products is also known in the agrochemical sector in particular. In addition to the literature already cited, reference may be made here to US-PS 5, 057,141 and the literature cited therein, especially R. Rodriguez-Kabana et al. in “Plant and Soil", 100, 237 to 247 (1987), where it is stated in particular that chitin-containing materials mixed with other organic nitrogen compounds, such as ammonium phosphate and urea, develop nematostatic and nematocidal activity towards phytopathogenic nematode populations in soils and, at the same time, rather than being phytotoxic, serve to nourish the plants. The teaching of US-PS 4,536,207 is along the same lines, said patent describing the nematocidal action of a chitin/protein complex compound obtained from a demineralised water-insoluble chitin material and a water- insoluble protein component.

The teaching according to the invention includes the use of such water-insoluble chitins as active substance component (a) or at least as part of this active substance component.

By contrast, one important embodiment of the technical teaching according to the invention is based on the object of being able to bring about a marked increase in efficacy precisely of nutrient mixtures (a) by using components based on chitin or chitosan, at least some of which are water-soluble. It is known that chitosan and chitosan compounds are obtained by the deacetylation of chitin. Although the primary product

H 3695 10 obtained, high molecular chitosan — especially with molecular weights in the region of 1 million or more — is as such insoluble or only poorly soluble in water and aqueous alkali solutions, it is known substantially to increase the solubility of this (these) chitosan component (s) by simple means. Thus the chitosan-based components dissolve in aqueous solutions of organic } and inorganic acids. itis also known that chitosan with a degree--of deacetylation of 50% is water-soluble. The water solubility can be increased by reducing the molecular weights to the range of chitosan oligomers; finally, the solubility can be adjusted over a wide pH range in water by means of simple chemical reactions — especially by carboxymethylation to O-CM-chitosan, N-CM-chitosan and/or N/O-CM- chitosan. Details of this basic knowledge of chitosans can be found, for example, in the cited publication entitled “Applications of Chitin and

Chitosan”, M.F.A. Gossen (ed.), Technomic Publishing AG, 1997, chapter 1 entitled “Applications and Properties of Chitosan”, Q. Li et al., pages 3 to 29, particularly pages 8 and 9.

As already made clear, the chitosans (a) to be used according to the invention can be oligomers and/or polymers of practically any desired molecular weight. In the manner already indicated, both low molecular weight oligomers and high molecular weight polymers can be converted to water-soluble forms which allow application to the soil and/or the aerial part of the plants and the spreading of the chitosan in the soil and especially into the region of the plants’ roots. Particularly suitable chitosan compounds in this connection can be those which also have sufficient water solubility especially in the neutral to weakly basic pH range and which have been modified in known manner — for example by salt formation with inorganic and/or organic acids, by lowering and regulation of the degree of polymerisation or oligomerization and/or by derivatization of the chitosans with solubilizing groups, for example carboxymethyl groups in the

O- and/or N- position.

J

'

H 3695 11

Although the published prior art also expressly describes the use of such chitosans or chitosan compounds in the agricultural sector, including the use of corresponding aqueous chitosan formulations, the combination essential to the invention, in terms of the multicomponent mixtures of components (a), (b), (c) and preferably also (d) defined according to the — invention, coupled with the objective according to the invention, on the one hand to increase plant growth and on the other hand to protect the plants from infestation by pathogens, particularly those responsible for fungal, bacterial and/or viral diseases, but also sucking pests, on the root — in this case nematodes for example — and/or on aerial parts of the plants, is not disclosed in said published prior art.

The introduction of chitosan components (a) into the soil regions to be treated and/or onto the aerial part of the plants can be carried out at the same time as the introduction of components (b), (c) and optionally (d), and/or at a different time. In one important embodiment, however, } provision is made for sufficiently water-soluble chitosans or chitosan compounds to be introduced into the soil structure and/or applied to the aerial part of the plants at least in part together with said other components of the nutrient mixtures according to the invention.

If chitins and/or particularly chitosans are used in the form of a mixture with components (a), (b) and optionally (d), the amounts used here are at least 0.05% by weight and especially at least 0.1 to 1% by weight, based in each case on the water-free multicomponent mixture. The crucial point is that even such small amounts of chitin-based or chitosan-based components can substantially influence the course of the vital processes in the soil and in the plant; in particular, the growth of the healthy microbial flora and hence of the plants is promoted and the growth of pests is suppressed. (b) “Ecologically safe surfactant compounds of the O/W type (APG

H 3695 12 compounds)

The biodegradable surfactants of subclass (b) used according to the invention are known to be compounds of non-ionic character which are also preferably at least predominantly based on natural substances and have preferred HLB values in the range 10 to 18.

According to the invention, it is particularly preferred to use, as component (b), at least partially, and especially at least predominantly, alkyl (oligo) glucoside compounds whose alkyl radical is at least predominantly derived from linear fatty alcohols. Compounds of this type — nowadays also termed APG components or compounds — are surface- active auxiliary substances with a wide range of applications. Several factors are important for their modern practical use on the industrial scale;

It is known that APG-based wetting agents can be completely based on natural substances. They are the reaction products obtained by reacting fatty alcohols with glucose, oligoglucoses or — in the case of simultaneous reduction of the chain length — polyglycosides such as starch, said reaction products having the general formula R-O-(G), in which R is a primary, preferably linear and aliphatic hydrocarbon radical having at least 6 C atoms, preferably 8 to 24 C atoms and particularly preferably 8 to 18 C atoms, and G is a glycose unit having 5 or 6 C atoms, preferably glucose.

In the surfactant class in question, the degree of oligomerization x — and hence the DP value — which indicates the distribution of monoglycosides and oligoglycosides, is normally between 1 and 10 and for example is in the range from about 1.2 to 5, preferably in the range from about 1.2 to 4 and particularly preferably in the range from 1.2 to 2. Reference may be made to the extensive specialized knowledge and literature on the preparation and nature of APG compounds of the type in question; cf., for example, the book by Hill et al. entitled “Alkyl Polyglykoside” (“Alkyl polyglycosides”), VCH-Verlagsgesellschaft mbH, Weinheim, 1997.

APG compounds as surface-active auxiliary substances in aqueous

Claims

H 3695 28 CLAIMS

1. The use of multicomponent nutrient mixtures of at least predominantly organic origin for the cultivation and care of useful and ornamental plants by activating the plants’ rhizosphere and/or phyllosphere and hence promoting both plant growth and plant health in combating — pathogens, particularly those responsible for fungal, bacterial and/or viral diseases, but also sucking pests, on the root and/or aerial parts of the plants, containing (a) chitin and/or chitosan of oligomeric and/or polymeric structure, applied, simultaneously and/or at different times, in combination with (b) ecologically safe surfactant compounds from the class of the alkyl(poly)glycosides of the O/W type (APG compounds) and (c) organic compounds which have lipophilic, saturated and/or olefinically unsaturated hydrocarbon radicals with a fatty structure and are both aerobically and anaerobically degradable.

2. The use claimed in claim 1, characterized in that P and/or N compounds, at least some of which have lipophilic radicals, and, if desired, carriers containing other macronutrients and/or micronutrients for plant growth are additionally introduced into the root region and/or applied to the aerial part of the plants as component(s) (d).

3. The use claimed in claims 1 and 2, characterized in that oil-soluble but biocompatible organic compounds with aliphatic and/or olefinically unsaturated, preferably at least predominantly linear hydrocarbon radicals which have at least 6 C atoms and especially at least 8 C atoms are used as component (c).

4. The use claimed in claims 1 to 3, characterized in that components (c) are used, at least some of which are functionalized with oxygen as a heteroatom, the use of fatty alcohols and/or fatty acids or derivatives thereof, such as their esters or partial esters, ethers and/or amides being preferred.

H 3695 29

5. The use claimed in Claims 1 to 4, characterized in that components (c) are at least predominantly based on natural substances.

6. The use claimed in claims 1 to 5, characterized in that at least some of components (c) have pour points of or below 25 to 30°C and especially of or below 10 to 15°C.

7. The use claimed in claims 1 to 6, characterized in that. lecithin, _ lecithin hydrolyzates and/or chemically modified lecithins are used as component (d) and may even be mixed with other N-containing components, although the concomitant use of such additional N components is preferably dispensed with for application of the multicomponent mixture to the aerial part of the plants, especially the leaves.

8. The use claimed in claims 1 to 7, characterized in that chitosans or chitosan compounds, at least some of which are water-soluble, are used as component (a) and are preferably introduced into the cultivated land or applied to the aerial part of the plants in the form of aqueous formulations.

9. The use claimed in claims 1 to 8, characterized in that chitosans of oligomeric and/or polymeric structure are used which have been obtained by at least extensive deacetylation of chitin and, if desired, reduction of the average molecular weight by chain cleavage of the aminosaccharide polymers.

10. The use claimed in claims 1 to 9, characterized in that chitosan compounds with improved water solubility — preferably also in the neutral to weakly basic pH range — are used, the solubility in water being ensured in known manner, for example ~ by salt formation with inorganic and/or organic acids, —- by lowering and regulation of the degree of polymerisation or oligomerization and/or — by derivatization of the chitosans with solubilizing groups, for example, carboxymethyl groups.

H 3695 30

11. The use claimed in claims 1 to 10, characterized in that APG compounds whose alkyl radical is at least predominately derived from linear fatty alcohols preferably based on natural substances are used as component (b), the HLB values of these surfactant components preferably being in the range 10 to 18.

12. The use claimed in claims 1 to 11, characterized in that APG compounds of glucose and fatty alcohols based on natural substances with at least 6 C atoms, preferably 8 to 24 C atoms, and DP values in the range

1.2 to 5 are used as component (b).

13. The use claimed in claims 1 to 12, characterized in that the multicomponent mixtures are used in the form of low-foaming aqueous formulations which contain olefinically unsaturated Ci2-24 fatty alcohols of natural origin, especially at least predominantly Cierg fatty alcohols with a high proportion of olefinic double bonds and solidification ranges of or below 20°C, preferably of or below 10 to 15°C, and/or fatty acid partial esters, such as glycerol monooleate, at least partly as components (c), mixtures of these components (c) also being usable.

14. The use claimed in claims 1 to 13, characterized in that the chitin- based and/or chitosan-based active substance components (a) in the nutrient mixture are present or used in amounts of at least 0.05% by weight, preferably in amounts of at least 0.1 to 1% by weight, based in each case on the water-free nutrient mixtures.

15. The use claimed in claims 1 to 14, characterized in that the chitin- based and/or chitosan-based multicomponent mixtures are applied in amounts of at least 0.2 g/m? preferably in amounts of 1 to 60 g/m” and particularly preferably in amounts of 10 to 40 g/m?, based on the water-free mixture.