WO1991018508A1

WO1991018508A1 - Composition against ozone damages to cultivations and method for its application

Info

Publication number: WO1991018508A1
Application number: PCT/EP1991/000972
Authority: WO
Inventors: Attilio Formigoni
Original assignee: Sostra S.R.L.
Priority date: 1990-05-28
Filing date: 1991-05-27
Publication date: 1991-12-12
Also published as: AU7894591A

Abstract

Composition to prevent ozone damages to cultivations, based on fatty acids of natural origin, both as such or as their salts or esters, like the triglycerides in oils or fats of vegetable or animal origin, preferably containing a high percentage of unsaturated fatty acids, possibly with the addition of antioxidants, chelating compounds for heavy metals, plant growth regulators, leafage fertilizers with macroelements, oligo-elements and chelated microelements, and possibly with emulsifiers, surfactants and inerts. Method for applying said composition by atomizing the same on the leaves in concentrated form, or diluted in solvents or emulsified in water, during the plants vegetation period, so as to prevent ozone from damaging the cultivations.

Description

"COMPOSITION AGAINST OZONE DAMAGES I'O CULTIVATIONS AND METHOD FOR ITS .APPLICATION"

=_=oOo=== BACKGROUND OF THE INVENTION Field of the Invention

The damages caused by ozone to field and tree cultivations - even if ozone is present at the height of the cultivation to a very slight extent (for instance, 0.03-0.10 ppm by weight in the atmosphere) - have been widely described since very many years, said damages being represented either by leafage necrosis, or by reduced flower fertiliza¬ tion and less production of fruits, seeds and leaves, with a considerably reduced productiveness of several cultivations.

Such damages have mostly been noticed in the agricultural re¬ gions of the more developed countries as, for example, North America, Europe, and the industrialized areas of other Continents, and they are generally tied to an inert ,_se in the ozone concentration at the height of the cultivation, determined by a simultaneous increase of air pollution originated from different pollutants. Ozone (0 ) at the height of the cultivation is in fact formed starting from atmospheric oxygen (0₉), as a result of a photochemic. _ eaction favoured by a bright sun radiation and by the presence of air pollutants, as nitrogen oxides, with the catalytic activity of different hydrocarbons, such pollutants being mostly present in highly industrialized areas. Nevertheless, such air pollutants are not only presen- where they are originated, but they are also carried away by the winds through long distances, thereby producing ozone also in agri¬ cultural regions which are very far from the polluting sources.

Though considering the more or less intense varietal sensitivity of the different plants, in various cases high damages caused by the pre¬ sence of ozone have been noticed on several harvests, such as to justify the search for different means allowing to reduce such damages. Description of the Prior Art

In the last decades, various products have been described allow- Z ing to reduce ozone damages to different plants, even if with occasional¬ ly contrasting results (for example: Siegel S.M. , Plant Physiol. 37,261 (1962): Dass H.C. and weaver G.M.. Can. J. Plant Sci. 8,50 (1968); Thompson C.R. & G. Katz. Calif. Agric. 24 (9) 12-13 (1970); Manning W.J. and Vardaro P.M., Phytopathology 63, 141 (1973J: Hager F.M. , German Pat. Appl. 2.238.053 (1973); Tomlinson H. and Rich S. , Phytopathology 63, 903 (1973): Moyer J. et Al. , Plant Dis. Rep. 58, 41-44 (1974); Takaoka J. et Al., Japan Pat. Appl. 75/40763 (1975); Gilbert M.D. et Al., Hort. Sci. 10,228-231 (1975); Walker J.T. and J. Melin, Plant Dis. Rep. 62,400 (1978): Hofgstra G. et Al., Plant Dis. Rep. 62,350 (1978); Okii M. et Al., U.S. Pat. 4,231,789 (1980); Rubin B. et Al. , Bull. Environ. Contam. Toxicol. 2.5, 623 (1980); Beckerson D.W. and D.P. Ormond, Hort. Sci. 21,1070 (1986)).

In particular, to reduce ozone damages to plants, use has been made at times of antioxidants (as ascorbic acid, propylgallate, alpha-to- copherol, diphenylamine); of plant growth regulators (as abscissic acid, cytoquinines); of thiocarbamic, benzimidazolic, triazolic or oxathiinic fungicides: of insecticide synergists (as piperonyl butoxide); or even of various amines, or other compounds (as glutathione) and - more frequently - the compound coded EDU (N-(2-oxo-I-imidazolydinyl)ethyl-N'-phenylurea) and derivatives (U.S. Patents 3,8.59,301, 3,973,946 and 4,0.55,412; Carna- han J.E. et Al., Phytopathology 68,1225 (1978)), the EDU being adopted as standard also recently in an international research project (0'Sullivan D.A. Chem. & Drug Eng. News 67,7 (1989)). It should nevertheless be pointed out that, after several deca¬ des of different searches in this field, none of the products developed so far is currently used for commercial purposes, and even the EDU com¬ pound is no longer commercially produced, both for reasons of costs - which are too high against economically unacceptable results - and for toxicological problems, deriving from the risk of pollution of the cul¬ tivations treated with chemical compounds which are potentially harmful if present as residues in food. SUMMARY OF THE INVENTION The object of the present invention is to therefore make up for the shortages existing in the phytosanitary field, in respect of the pre¬ vention of damages caused to cultivations by tropospheric ozone, by sup- plying a composition of reduced cost and not toxic for the plants, as well as for the animals and for mankind, which is useful to reduce the aforecited ozone damages.

Another object of the present invention is to supply a method and a dosage to apply said composition, allowing to obtain the best re- suits in reducing ozone damages.

According to the invention, said objects are reached by means of a composition based on fatty acids of natural origin, preferably unsatu¬ rated, or their salts and esters, as in particular the triglycerides con¬ tained in oils and fats of vegetable or animal origin. Said composition is preferably applied with a method according to which it is distributed on the plants, before any ozone damages are caused thereto, by being ato¬ mized thereon iq an amount of between 0.1 and 100 litres per hectare of fatty acids or of oils or fats.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION It is known that the double bond between carbon atoms of olefi- nic compounds reacts with ozone to form intermediates of different compo¬ sition, generically defined as ozonides, with subsequent decomposition thereof and formation of different compounds, giving rise to the process defined as ozonolysis, usually employed in organic chemistry to study the molecular structures of unsaturated organic compounds, either synthetic or natural.

However, in order to easily obtain such ozonolysis reaction, it is necessary to operate with laboratory methods such as to allow the re¬ action to take place in a quantitative way and within acceptable times. It is necessary, for instance, to usually operate with the unsa¬ turated compound diluted in a solvent which is inert for ozone (as chlo¬ roform, carbon tetrachloride. glacial acetic acid, low boiling saturated _ fractions of petroleum, and so on), through which is caused to flow an air stream enriched with a high ozone concentration.

To allow the subsequent rapid decomposition of the formed ozoni- des. it is useful to treat them with reducing agents in order to obtain aldehydes and/or ketones, or to oxidize them so as to obtain acid deriva¬ tives.

It is also known that natural oils and fats containing unsatura¬ ted fatty acids, if exposed to air for a certain time, slowly undergo oxidation due to the action of atmospheric oxygen, more frequently with the formation of small quantities of hydroperoxides on the alpha carbon close to the double bond, with subsequent cracking of the double bond and formation of different compounds (as aldehydes and/or ketones).

In natural conditions, ozonolysis does not take place rapidly in a quantitative way, owing to the very low ozone concentration normally existing at the tropospheric level (for example, 0.01-0.07 ppm) .

It is known, in fact, that if unsaturated fatty acids of natural origin, or their salts and esters, are caused to react in the presence of air containing very low ozone concentrations - equivalent to those exis¬ ting in natural conditions - the reaction kinetics is such as to require very long reaction times (for example, several years) in order to react the ozone present in such a low concentration and thereby reduce the ozo¬ ne level, in natural conditions, below the plant damaging threshold.

From the above it ensues that the expert of the art, though be¬ ing acquainted with the reactivity of ozone with olefinic compounds, un- der controlled laboratory conditions and in the presence of high ozone concentrations, was not led to consider important - from the quantitative point of view and from that of the reaction speed - the reactivity of un¬ saturated fatty acids of natural origin, or of their salts and esters, in a natural environment, that is, in presence of air with very low ozone concentrations. Furthermore, the chemical reactions through which ozone damages the plants after penetrating into the leaves through the stomata. are widelv known: in fact, ozone reacts inside the leaves with the double £T bonds of the unsaturated organic compounds present in the membranes and in other cell components, forming at first ozonides from which various peroxidized free radicals are then released damaging different enzymatic reactions, with disturbance of the cell walls permeability and with dis- tortion of the photosynthesis process and of the proteic metabolism of the plants (Hewitt CN. et Al., Chemistry and Industry, Aug. 1990, 478-481).

It is also known _. ~ the volatile olefinic compounds produced by plants and present, for e_ .^■ pie, in the air of forest regions, react - even if not quantitatively - with tropospheric ozone, producing a large number of free radicals with subsequent formation of hydroperoxides (Martinez R.I. et Al. , J. Am. Chem. Soc. 103, 3807-3820 (198l); Hellpoin- ter E. and Gab S., Nature 337, 631-634 (1989)).

Such free radicals and hydroperoxides which form in the air of agricultural regions, helped also by the favourable action of humidity, could lead to an increase of the endogenous damages caused to plants by ozone, once they had penetrated into the leaves through breathing of the plant (Becker K.H. et Al., Nature 346, 256-258 (1990)).

To thus reduce ozone damages to cultivations, on the basis of the data published in scientific literature, the expert of the art would have been led to consider the use of natural unsaturated fatty acids or their salts and esters as fully useless from the practical point of view, since it involves very long reaction kinetics in natural conditions; on the other hand, he would have been faced with the doubt that such olefi- nic compounds, on reacting - though to a minimum extent - with ozone, could have caused in natural conditions the formation of further peroxi¬ dized free radicals, particularly harmful for the plants, thereby increa¬ sing the damages caused by ozone to cultivations.

Viceversa, the inventor of the present invention was able to discover during his searches that, contrary to all expectations based on known scientific knowledge, if unsaturated fatty acids of natural origin or their salts and esters - like the triglycerides contained in oils and 4 fats of vegetable and animal origin - are distributed on the cultivations in a suitable way. instead of increasing the damages caused to plants by ozone, they allow to obtain the unexpected result of reducing said dama¬ ges on the cultivations which have undergone said treatment. On the basis of present scientific knowledge, it has however not been possible, up-to-date, to give a full theoretical explanation to the actual mechanism which determines this fully unexpected result. Factors that are still unknown could in fact be involved, as an unexpected mecha¬ nism of enhancement of the reactivity of natural unsaturated fatty acids with tropospheric ozone at leafage level, following the starting - in said particular environment - of possibly catalyzed self-enhancing chain reactions, which give rise to fully unexpected quantitative results.

This invention is of considerable importance not only because it makes use of compositions which are generally economic, but also because such compositions - based on natural fatty acids or their salts and est¬ ers, as oils or fats of vegetable or animal origin - are not phytotoxic for the plants in the required doses of use, they apply no polluting sub¬ stances on the cultivations thus treated, and they are highly biodegrada¬ ble, without disturbing the biological balance and the natural environ- ment.

There are a good number of fatty acids of natural origin, which can be usefully employed in a composition against ozone damages to culti¬ vations, but they are all essentially derived from natural oils and fats, both vegetable and animal.

Usually, vegetable or animal oils and fats contain mixtures of triglycerides based on fatty acids of different kind, both saturated and unsaturated, which are mostly difficult to separate even with very comp¬ licated industrial processes (as hydrolysis at high temperature and higji pressure, with use of reagents and catalysts, often operating in vapor streams or with inert gases, or proceeding by fractioned distillation or by chromatographic separation) .

The result is that the natural fatty acids present on the market _- are not pure products, but they generally consist mostly of mixtures wherein there is possibly a predominant component.

Such mixtures usually contain either saturated fatty acids (as caproic, caprylic. capric, lauric, myristic, palmitic, stearic, arachic, behenic, lignoceric acid, and the like), or monounsaturated fatty acids (as caproleic, lauroleic, myristoleic, palmitoleic, oleic, ricinoleic, vaccinic, gadoleic, cetoleic. erucic, brassidic, selacoleic acid, and the like), or even poly-unsaturated fatty acids (as linoleic, linolenic, ira- gonic, oleostearic, tricosanic, arachidonic, eicosapentenoic acid, and the like).

The most active compositions against ozone damages to cultiva¬ tions are those containing a higher content of unsaturated fatty acids, even if said unsaturated fatty acids are mixed with saturated fatty acids, as for example compositions with a higji content of oleic acid, linoleic acid, linolenic acid, erucic acid, and so on.

The fatty acids of the present invention may be salified by al¬ kaline metals (as sodium, potassium), or they may be esterified with lo¬ wer alcohols (as methyl, ethyl, isopropyl alcohols, and so on), but more commonly such fatty acids are to be found as triglyceride esters in oils or fats of vegetable origin, or also in oils or fats of animal origin.

There are a great number of vegetable oils and fats which can be most commonly used to reduce ozone damages to cultivations, and they usually originate from the milling and pressing of seeds, or of other parts of various so-called oleiferous plants, often followed by extrac- tion with solvents from the obtained pressed seeds, and possibly also by a further process of rectification and purification.

The vegetable oils which can be used in compositions against ozone damages are, for example, the following: linseed, soybean, cotton, sunflower, corn, sa flower, grapestone, rapeseed, peanut, sesame, olive, castor-oil, tall-oil, palm, coconut; though other vegetable oils can be used (as wheat, barley and rice germ oils, cucurbitaceae seed, almond. Neouli. Perilla. Oitica. Tung oils, and so on), but at generally higher 9 costs.

Even if a large number of vegetable oils are suited for this use. those which have proved to be the most interesting in order to redu¬ ce ozone damages are the ones with a higher content of unsaturated fatty acids and, in particular, of poly-unsaturated fatty acids, as for exam¬ ple, oils of linseed, soybean, grapestone, safflower, cotton, corn, sesa¬ me, sunflower, tall-oil, and so on; though use can also be made of oils with a lower content of poly-unsaturated fatty acids but rich in mono-un- saturated fatty acids, as olive oil, rapeseed oil, peanut oil, castor-oil and so on.

It is of course also possible to use mixtures of such vegetable oils, as oils of different seeds obtained from by-products, and thus of particularly low cost (for example, mixtures of oils of soybean, cotton, sunflower, peanut, rapeseed, palm, and so on). Likewise, use can also be made of compositions based on oils or fats derived from animals, obtained for instance from terrestrial Mamma¬ lia (bovines, swine, equines, sheep and goats, and so on), as for example tallow oil, olein, bovine feet and bone oil, all obtained with different processes (for example, extraction with solvents subsequently eliminated by distillation, heating up followed by cooling or winterization to sepa¬ rate the lower melting components, or other processes) .

Equally, use can be made of compositions based on oils of sea animals, like oils of cetaceans (as whales, sperm-whales), or fish oils (as cods, herrings, sardines, sharks, and so on). In the event of disposing of fatty substances which are not li¬ quid at ambient temperature, their practical use in a composition accord¬ ing to the invention is^'possible if such fats are dissolved into suitable solvents (as hydrocarbons, alcohols, ketones or glycols, which are not phytotoxic for the cultivations). According to a particular aspect of the present invention, some special adjuvants are added to the fatty acids of natural origin, or to their salts and esters, or to the aforementioned oils and fats of veeeta- ble and animal origin diluted into solvents, which adjuvants have proved in different cases to possess a synergic strengthening effect in reducing the ozone damages.

Such adjuvants with a synergic effect can be grouped into the following categories: a) Antioxidants, as propyl-, octyl-, lauryl-gallate, and other gallic acid esters; butyl-hydroxy-toluene; butyl-hydroxy-anisole: ethoxyqui- ne: diphenylamine; naphthyl-phenylamine; ascorbic and erythrorbic acid and their salts and esters; tocopherols; mono- or di-ter-butyl-hydro- quinone and other hydroquinones; dithiopropionic acid and its salts and esters; 4-hydroxymethyl-2,6-di-ter-butylphenol; nordihydroguaia- retic acid; propylethylguaetol; 2,4, 5-tri-hydroxybutyrophenone; and other antioxidants well known to the expert of the art. Such antioxi¬ dants can also be used in different mixtures: in fact, the reciprocal strengthening effect of their action is known in various cases. b) Chelating compounds for heavy metals - which can reduce the action of the antioxidants - as citric and tartaric acid and their salts and esters; phosphoric acids and their salts and esters; organic chelating compounds as EDTA, HEDTA, DPTA, EDDHA, HEP, heptagluconates, or diffe- rent aminoacids, also in mixtures derived from hydrolysis of animal or vegetable proteins. c) Plant growth regulators, as concentrated extracts from seaweeds con¬ taining cytoquinines (zeatine, benzyl- and furfuryl-adenine, and so on), gibberellines, auxines, abscissic acid, or other plant growth regulators of natural or synthetic origin. d) Fertilizers, containing macro-elements as nitrogen (for example, ni¬ trogenous inorganic and organic fertilizers, as hydrolized animal epi- thelia or hydrolized vegetable substances, like soybean proteins, sea¬ weeds, yeasts, fungi or bacteria or fermentation residues, all inclu- ding polypeptides or aminoacids. as well as other natural substances); or else containing phosphorous (for example, different phosphates), or even potassium (as potassium salts) . or containing oligo-elements (as magnesium, calcium and sulphur) and/or microelements (as boron, molib- denum, iron, manganese, zinc, copper, cobalt, and so on), the heavy metals being preferably present as chelates.

To improve the use of the composition according to the invention - for instance, with water emulsified compositions - it may eventually be helpful to further add surfactants and/or emulsifiers: for example, mono- and diglycerides of fatty acids and their esters: ethoxylated and/or pro- poxylated alcohols, alk lphenols, amines, fatty acids, oils and fats; esters of fatty acids, of glycerol and of glycols; lecithin and derivati- ves; phosphate and sulphate esters; sorbitan-derivatives; saccharose es¬ ters and derivatives; sulphates and sulphonates of oils, of fatty acids, of aromatic and aliphatic derivatives; succinates and their sulphoderiva- tives; various polyoxyethylene and polyoxypropylene copolymers, and so on (see list of such commercial surfactants and emulsifiers on the publica- tion: McCutcheon's-Detergents & Emulsifiers, Glen Rock, N.J., USA).

The expert of the art shall use said emulsifiers on the basis of the optimal hydrophilic-lipophilic balance that one wishes to obtain for the compositions after their water emulsion, by making use of the most suitable products and/or their mixtures in the optimal quantity, in order to obtain water stable emulsions, without the forming of persistent foam, eventually also adding further anti-foam agents, as for instance silicone compounds. Also inerts could be added to the composition, as for example different solvents and co-solvents (like alcohols, hydrocarbons, polar solvents, and so on), as well as organic liquids like glycols or even 1 water (in the event of oil-in-water and water-in-oil emulsions of the "mayonnaise" type), possibly also adding thickening and suspending agents, as alginates or xanthane gum and even bentones.

A composition according to the present invention could thus for example be composed as follows:

Q Fatty acids or their salts and esters (as oils or fats of vegetable or animal origin) \ -\ 00% //

Antioxidants 0-20%

Chelating compounds 0-10%

Plant growth regulators 0-20%

Surfactants and emulsifiers 0-30%

Fertilizers 0-50%

Inerts (as solvents, suspending and diluting agents) 0-99%

Another object of the present invention is to use a special method for applying said composition - based on fatty acids of natural origin or their salts and esters, as the triglycerides present in oils and fats of vegetable or animal origin - which allows to obtain the best results in reducing ozone damages to cultivations.

The previously described composition according to the invention, based on fatty acids of natural origin or their salts and esters, should be atomized on the cultivations having to be protected from ozone damages in the right periods, that is, before any such damages occur and when the plants are most sensitive thereto, which means before, during and after blossom time, so as to protect flower fertilization, or during and after the leaf growth period, in which ozone penetrates

the stomata causing various damages. Said technique of preventive defence thus requires the possible repeated use of the composition according to the invention, for instance at intervals of 7-14 or more days, with the object of keeping protected the growing vegetation and of preventing any possible degradation of the composition throughout time, after it has been distributed on the culti- vations.

The composition can be applied with suitable equipment (as spray pumps and/or atomizers, operating on ground or also on air means), which distributes on the plants high volumes of liquids (for instance, 500-5000 1/ha), medium volumes (for instance 100-500 1/ha), low volumes (for ins- tance 20-100 1/ha). or even very low volumes of liquids (for instance The composition based on fatty acids or their salts and esters. or on vegetable or animal oils or fats, can either be highly concentrated (up to using the fatty acids or the oils as such), or more diluted, by adding various adjuvants and inerts as previously described, and by pos¬ sible subsequent water emulsion before being atomized on the plants.

In the event of using fatty acids or vegetable or animal oils as such, or in highly concentrated form, it will be necessary to operate with equipment (for instance pneumatic, with rotary nozzles, or the like) apt to atomize fairly reduced quantities of relatively viscous liquids per surface unit, adopting the low or very low volume spraying technique.

Said technique is also very suitable for application by air means (for instance, aircrafts or helicopters).

In the event of using instead a more diluted composition, con- taining additives, emulsifiers and different adjuvants, use can be made of more common equipment apt to spray on the plants water emulsions of fatty acids or their salts and esters, or of vegetable or animal oils or fats diluted in water, taking care to cover the cultivations as far as possible with finely atomized mixtures, adopting the previously defined atomization technique with low, medium or high volumes of liquids.

It is anyhow particularly important for the compositions to be atomized and/or sprayed in such a way as to cover the sides of the leaves containing the stomata openings, through which ozone penetrates into the leaves. The doses of use of the composition according to the invention can vary within fairly wide limits, according to the growth of the field or tree cultivations having to be protected, to their lower or higher varietal sensitivity, to the lower or higher levels of ozone present in the air, and thus according to whether the damages which may be caused will be more or less serious, which damages should anyhow be avoided by always using the composition by way of prevention, that is, before any ozone damages occur. 12

The useful doses of the composition according to the invention will be such as to distribute quantities of fatty acids or their salts and esters, or of vegetable or animal oils and fats, included between 0.1 and 100 litres per hectare: for field cultivations, such quantities may vary from 0.1 to 50 litres per hectare, with preferential doses of 0.3 to 20 litres per hectare; while for tree cultivations, the quantity having to be distributed may vary from 0.2 to 100 litres per hectare, with pre¬ ferential doses of 0.6 to 40 litres per hectare.

The composition according to the invention can be distributed on the cultivations, in different cases, also mixed with chemical products for crop protection (for instance, fungicides, insecticides, acaricides, selective herbicides, and the like), and this can give rise to positive phenomena of mutual interaction.

There are a great number of cultivations which are sensitive to damages caused by ozone. Among the agricultural ones there are, for exam¬ ple, tobacco, soybean, cotton, sweet-potato, peanuts, white potato, sun¬ flower, rape, flax, safflower, castor bean, sugar beet or forage beet, lrcern and clover, forage peas, or cereals as wheat, barley, rice, and in.nor cereals like rye, oats and triticale, as well as corn and sorghum. Among the horticultural ones, those more likely to be affected are the Cucurbitaceae (as water-melons, melons, marrows),- the Solanaceae (like tomatoes, peppers, aubergines) , the leguminous plants (as beans, French beans, broad beans, peas⁾, the cruciferous plants (as cabbage, cauli¬ flower, turnips), the Chenopodiaceae (as spinach, beet-root), the Umbel- liferae (as fennel, carrot), the Compositae (as salads of various types and artichokes), and other horticultural cultivations. Also several flo- ricultural and ornamental plants are s^ensitive to ozone damages, as for instance, carnations, roses, gerberae. and others. The fruit cultivations which can be protected include vines. Pomaceae (as apples and pears) . Drupaceae (as peaches, plums, cherries, apricots), kiwi, citrus fruits, the berry fruits (as strawberries, black-currant, raspberries, bilber¬ ries, and the like), and also the hop. J . In various cases and in particular regions, also tropical plants need to be protected, as banana, coffee, tea. sugar-cane, caoutchouc, -jute. and the like.

Even ornamental and forest trees are often quite sensitive to 5 ozone damages as, for example, coniferous trees and various broad-leaved trees (as the poplar). In this respect, one should remember the serious problem of the death of forests in the industrialized countries, caused by the presence of ozone, by the concomitant phenomenon of acid rains, by recurrent years of drought, and by different interacting factors. 0 The examples which follow are meant to illustrate the invention more clearly, without however limiting its possible applications.

FORMULATION EXAMPLES Example 1

Highly concentrated compositions of fatty acids, liquid at amb- 5 ient temperature, or of oils of vegetable or animal origin for use with very low and low volumes of liquid (as 1-100 1/ha) were prepared, using compounds as such, both refined and raw, or else mixing therewith small quantities of adjuvants and/or diluents, apt to facilitate their distri¬ bution by atomization with suitable equipment and to improve their ef- 0 fectiveness, as in the following compositions (weight percentages):

Composition N. 1 2 3 4 5 0 7 8

Liquid fatty acids or vegetable or animal oils 90 95 97 98 9^{Q Q}9-7 99

Propylene glycol 10

--> Isobutvl alcohol

Sorbitan monolaurate

Ethoxylated castor-oil with 3 moles of ethvlene oxide

Polyethoxylated nonylphenol

30 with 0 moles of E.O. /_-

Butyl-hydroxy-toluene 0.3

Diphenylamine 1

Propyl-gallate 1

Mono-ethyl-citrate 2

Example 2

Compositions based on liquid fatty acids or on water erπulsifi- able vegetable or animal oils were prepared by mixing with various emul¬ sifiers and adjuvants as in the following compositions (weight percenta¬ ges):

Composition N. 0. 10 11 12 13 14 15 l6 17

Liquid fatty acids or vegetable or animal oils 90 70 88 78 50 68 40 1 50

Polyethoxylated sorbitan monolaurate with 20 moles of ethylene oxide 5 14 5 5 7 6 5 2 2

Polyethoxylated castor-oil with 13 moles of E.O. 2 8 2 3 4 3 2 1 1

Polyethoxylated nonylphenol with 5 moles of E.O. 3 8 3 2 4 3 3 1 1

Polyoxyethylene-polyoxypro- pylene copolymer 6

Diphenylamine 2

Propylgallate 3

Laurylgallate .- .__ 2

Butyl-hydroxy- oluene 20

Mono-isopropyl-citrate 3 10

Dried extracts from Ascophyllum seaweeds hydrolized with alkali 20 iL

Animal epithelium hydrolized with 14% N acids 30

Urea 46% N 15

Urea 70% - 30% monopotassium phosphate 50

Isobutyl alcohol 6 4

Bentone

Water 20 45 I^Q

Example 3 Compositions based on water emulsifiable vegetable oils were prepared by mixing with various emulsifiers and adjuvants as in the fol¬ lowing compositions (weight percentages) :

Composition N. 18 19 20 21 22 23 24 25

Vegetable oils 90 70 89 77 50 68 40 1 Sorbitan monolaurate 4 3 4 5 5 4 4 1

Polyethoxylated castor-oil with 3 moles of E.O. 5 7 5 5 7 5 5 1

Polyethoxylated nonylphenol with 9 moles of E.O. 1 20 1 1

Diphenylamine

Propylgallate

Butv1-hvdroxv-toluene 20

Mono-ethyl-citrate 3 10

Dried extracts from Ascophyl- lum seaweeds hydrolized with alkali 20

Animal epithelium hydroli¬ zed with 14% acids 30 II

Urea 70% - 30% monopotassium phosphate 50

Isobutyl alcohol

Bentone

Water 20 46

Example 4

Compositions based on liquid fatty acids or vegetable or animal oils, in the form of thicker "mayonnaise" type emulsions or as thinner emulsions, were prepared with suitable equipment by emulsifying the oils

10 with various emulsifiers in the presence of water, according to the fol¬ lowing compositions (weight percentages):

Composition N. 26 27 28 29

Vegetable or animal oils 50 60 26 60

Glyceryl-mono-isostearate

15 Polyethoxylated glyceryl-mono- isostearate with 20 moles of E.O.

Sorbitan mono-oleate

Polyethoxylated sorbitan mono- oleate with 20 moles of E.O.

20 Water 44 30 70 28

APPLICATION EXAMPLES

Example 5

A sealed cell, containing ozone produced by a special ozonizer, was formed into part of an air-conditioned green-house with automatic

-^•. regulation of the temperature, humidity and light (by Osram Flora type fluorescent lamps, mixed with mercury-vapor lamps).

The ozone level in the cell was checked with an automatic ozone analyzer Model DASIBI lOlS. and said level was maintained so as to repro- Iβ duce the conditions normally present in an open field, in regions with a high ozone formation at the height of the cultivation (for instance, 0.03-0.05 ppm in the morning, 0.05-0.08 ppm in the afternoon, according to the increase in sun radiation). To be noted, moreover, that the introduction of ozone into the cell was started gradually at sunrise and was stopped after sunset, so as to reproduce - also through the time of exposure at the various ozone levels - what happens in nature.

The temperature within the cell was kept - with nigjit and day cycles - at 20-25°C, and the relative air humidity was kept at 50-70%.

Plants likely to be affected by ozone damages, as tobacco (Vir¬ ginia Bright variety), or French beans (Pros Gitana variety), or even water-melon (Toro variety), were cultivated in pots of 15 cm diameter, into a normally fertilized and irrigated agricultural soil, and preserved in the green-house in an ozoneless environment.

When some leaves had grown on the plants, the same were treated with the compositions according to the invention, using special equipment allowing to evenly distribute said compositions on the plants by atomiza- tion, after having possibly diluted them into sufficient water, usually 50 ml of liquid mixture for 4 pots and per square meter of surface.

Each composition was in fact sprayed on 4 pots, so as to dispose of statistical repetitions of the experiment, and 8 pots of each plant were not treated but left as untreated witnesses.

After having been preventively treated with the compositions ac- cording to the invention, the plants in their pots were introduced into the ozone cell and kept therein for 7 days.

Together with the plants treated with compositions against ozone damages, also the untreated witness plants were put into the cell.

After 7 days, the plants were removed from the ozone cell for a few hours and the treatment against ozone was repeated in order to pro¬ tect the newly grown leaves; the pots were then reintroduced into the ozone cell, together with the untreated witness plants, for 7 more days. IS

After 14 days from the first treatment, it was proceeded to reckon on the treated plants the percentage of leaf surface damaged by necrotic spots, adopting the conventional technique and converting said damage into percent of leafage necrosis, always in comparison with the damage found on the untreated witness plants.

A first series of results, obtained with various types of liquid fatty acids or of animal oils used in different concentrations, is repor¬ ted in Table 1. From the data reported in said Table, it can be noticed how the compositions according to the invention, based on liquid fatty acids, on their potassium salts, on alkyl esters or on animal oils, are apt to substantially reduce the damages of leafage necrosis caused by ozone on the treated plants, as compared to the damages which can be found on the untreated plants.

In particular, it can be observed how linoleic acid, its potas¬ sium salt or ethyl ester and the fish oils (richer in poly-unsaturated fatty acids) show a stronger activity than that of oleic acid and of tallow oil, which are in any case quite effective.

TABLE 1 Average percent of necrotic leaf surface caused by ozone on different cultivations treated every 7 days, after 14 days of permanence in the ozone cell.

Percent leafage necrosis on plants

2.0

Linolenic acid 80%

Potassium oleate 95%

Potassium linoleate 90%

Ethyl oleate 95%

Ethyl linoleate 90%

Refined cod oil

Winterized herring oil

Tallow oil

Untreated witness 50 40 22

Example 6

In the ozone cell, the method was carried out using the techni- que described in Example 5, on Tobacco plants Virginia Bright variety treated with different compositions according to the invention, always taking as comparison untreated witness plants.

The results obtained are reported in Table 2, from which it can be noticed how the compositions N. 12 and N. 11, based both on 90% oleic acid and on tallow oil, with addition of antioxidants (respectively pro¬ pylgallate, added with mono-isopropyl-citrate acting as chelant for heavy metals, and diphenylamine) have allowed to obtain - with equal doses of fatty acids or of oils and of antioxidants - far better results in redu¬ cing the ozone damages, thus evidencing an unexpected phenomenon of sin- ergy, between the fatty acid or the animal oil and the antioxidants, in protecting the plants from ozone.

It can be noticed, furthermore, how the compositions according 2/ to the invention have a greater effectiveness in respect of the EDU pro¬ duct currently used as an international standard in experiments against ozone damages.

TABLE 2 Average percent of leafage necrosis caused by ozone on different plants treated every 7 days, after 14 days of permanence in the ozone cell.

Leafage necrosis Tobacco Virginia Bright variety

31 15 10

30 25

20

15

8 5

10

17 12

12

1

18 12 10

34

Diphenylamine (see Note 2) 0

" 30

9

EDU (as such in g/m^" ) 0.01 40 0.1 35

Untreated witness 40

Notes to Table 2:

1 ) = Doses of propylgallate and of mono-isopropyl-citrate equivalent to those contained in composition N. 12, with doses of oleic acid or of tallow oil equal to 0.01-0.1-1 ml/πT.

2) = Doses of diphenylamine equivalent to those contained in composition

N. 11, with doses of oleic acid or of tallow oil equal to 0.01-0.1-1

2 ml/m .

Example 7 In the ozone cell, the method was carried out using the techni¬ que described in Example 5, on Tobacco Virginia Bright variety, on French beans Pros Gitana variety, and on Water-melons Toro variety, treated with different compositions according to the invention, always taking as com¬ parison untreated witness plants. The results obtained with various types of vegetable oils used in different concentrations are reported in Table 3- From the data repor¬ ted in said Table, it can be noticed how the compositions according to the invention, based on various types of vegetable oils, substantially reduce the damages of leafage necrosis caused by ozone on the treated plants, as compared to the damages which can be found on the untreated plants. In particular, it can be observed how raw soybean oil (containing tocopherols and other natural substances) shows an increased activity as compared to that of refined soybean oil.

TABLE 3 Average percent of necrotic leaf surface caused by ozone on dif- ferent plants treated every 7 days, after 14 days of permanence in the ozone cell.

Percent leafage necrosis on plants

Compositions as N. l8 based on vegetable oils from the plants mentioned below

Flax

Soybean (refined)

Cotton

Safflower

Grapestone

Sunflower

Corn

Peanuts

Sesame

Tall-oil

Castor-bean

Rape

2V

In the ozone cell the method was carried out, using the techni¬ que described in Example 5, on Tobacco plants Virginia Bright variety treated with different compositions according to the invention, always taking as comparison untreated witness plants.

The results obtained are reported in Table 4, from which it can be noticed how the compositions N. 21 and N. 20, based both on linseed oil and on soybean oil, with the addition of antioxidants (respectively propylgallate, added with mono-ethyl-citrate acting as chelant for heavy 5 metals, and diphenylamine) have allowed to obtain - with equal doses of vegetable oils and of antioxidants - far better results in reducing the ozone damages, thus evidencing an unexpected phenomenon of sinergy, bet¬ ween the vegetable oils and the antioxidants, in protecting the plants from ozone. 0 It can be noticed, furthermore, how the compositions according to the invention have a greater effectiveness in respect of the EDU pro¬ duct currently used as an international standard in experiments against ozone damages.

TABLE 4 5 Average percent of leafage necrosis caused by ozone on different plants treated every 7 days, after 14 days of permanence in the ozone cell.

Compositions used Doses ml. __^*" % Leafage necrosis of oils Tobacco Virginia

- Bright variety 2 S^"

N. 18 based on 0.01 18 linseed oil 0.1 10

1 8

N. 18 based on 0.01 20 soybean oil 0.1 13

1 10

N. 21 based on 0.01 11 linseed oil 0.1 3

1 0

N. 21 based on 0.01 13 sovbean oil 0.1 4

1 0

N. 20 based on 0.01 12 linseed oil 0.1

1

N. 20 based on 0.01 13 soybean oil 0.1 5

1 0

Propylgallate + (see Note 1) 70 mono-ethyl-citrate II 50

11 35

Diphenylamine (see Note 2) 70

II 30

11 20

EDU (a^ such 0.01 50 in g/m^") 0.1 30

Untreated witness 70

Notes to Table A-

1) = Doses of propylgallate and of mono-ethyl-citrate equivalent to those contained in composition . 21, with doses of oils equal to 0.01-0.1-1 ml/m".

2) = Doses of diphenylamine equivalent to those contained in composition

2 N. 20, with doses of oils equal to 0.01-0.1-1 ml/m . 2έ

Example Q

French beans of the Pros Gitana variety and Water-melons of the Toro variety were sown on two different plots of land of a field with slimy-sandy soil, duly fertilized and irrigated, and the plants were di-

2 ° vided into lots of 20 m^" (4x5 m) for the French beans, and of 40 m^" (8x m) for the Water-melons, so that each composition according to the inven¬ tion could be applied separately on each lot, having at the side of each treated lot an equal surface of untreated witness plants.

The same type of experiment was repeated 4 times for each culti- vation and for each type of treatment, with statistical distribution, applying the compositions during the following periods:

- before blossom time

- during blossom time

- after blossom time and subsequently repeating the treatment every 12 days up to harvesting time.

When each treatment was carried out, the ozone level present in the air was detected with the portable DRAEGER analyzer, noticing on an average, half-way through the afternoon, 0.03-0.05 ppm of ozone in the first vegetation periods (May/June) and 0.05-0.07 ppm of ozone in the periods which followed (July/August) .

Table 5 shows the compositions tested and the results obtained. The results reported in Table 5 reveal how the compositions according to the invention, based on 90% oleic acid or on tallow oil, allow to obtain also on field - in presence of harmful ozone levels - significant reduc¬ tions in the damages to leaves.

From Table 5 it^"can also be seen that the most productive re¬ sults can be obtained using the compositions N. 11 (oleic acid or tallow oil with addition of diphenylamine as antioxidant), or N. 14 (oleic acid or tallow oil with addition of dried extracts from Ascophyllum type seaweeds hydrolized with alkali, which are rich in natural plant growth regulators), or even N. 15 (oleic acid or tallow oil with addition of 2? animal epithelium hydrolized with acids, containing 14% of organic nitro¬ gen). These results clearly prove that such compositions - mixed with an antioxidant, or with seaweed extracts containing natural plant growth re¬ gulators, or even with a fertilizer based on organic nitrogen obtained from hydrolysis of animal, epithelium - give rise to an unexpected syner¬ gic strengthening action, with the additional advantages deriving there¬ from.

It is in fact remarkable how the use of the antioxidant or of the seaweed extracts or of the hydrolized epithelium, all as such - in doses corresponding to those contained in the compositions according to the invention - is not apt to reduce the percentages of leafage damages; whereas, the different mixtures allow to considerably increase the effec¬ tiveness of the compositions based only on oleic acid or on tallow oil (Composition N. 9).

TABLE 5 Average percent of leafage necrosis and unitary production at harvesting time on field cultivations, in presence of harmful ozone levels and with various anti-ozone treatments repeated during the vege¬ tation period.

Percent leafage necrosis on plants

Compositions used Doses ml/m French bean Water-melon of oleic acid Pros Gitana Toro or tallow oil variety variety

N. 9 based on 0.1 20 21 90% oleic acid 1 15 12

N. Q based on 0.1 25 28 tallow oil 1 18 20

N. 11 based on 0.1 12 15 Q0% oleic acid 1 5 7 N. 11 based on 0.1 15 20 tallow oil 1 12 ^•≥Θ

N. 14 based on 0.1 lb 17 90% oleic acid 12

N^". 14 based on 20 tallow oil 3 11

N. 15 based on 12 15 90% oleic acid 7 10

N. 15 based on 18 20 tallow oil 12 Q

Diphenylamine 30 36 20 30

Dried extracts from 32 35 hydrolized seaweeds 30 36

Hydrolized

31 39 animal epithelium 28 30

Untreated witness 30 35

Notes to Table 5:

1) = Doses of diphenylamine equivalent to those contained in composition

/ 2 N. 11, with doses of oleic acid or tallow oil equal to 0.1-1 ml/m .

2) = Doses of dried extracts from seaweeds hydrolized with alkali, equi¬ valent to those contained in composition N. 14, with doses of oleic

2 acid or tallow oil equal to 0.1-1 ml/m".

3) = Doses of animal epithelium hydrolized with acids, equivalent to those contained in composition N. 15, with doses of oleic acid or tallow oil equal to 0.1-1 ml/m .

Example 10 French beans of the Pros Gitana variety and Water-melons of the

Toro variety were sown on two different plots of land of a field with slimy-sandy soil, duly fertilized and irrigated, operating with the same method reported in Example 9. Table 0 reports the compositions tested and the results obtained. The results reported in Table 0 show how the compositions accor- 23 ding to the invention, based on vegetable oils, allow to obtain also on field - in presence of harmful ozone levels - significant reductions in the damages to leaves and considerable production increases.

From Table 6 it can also be seen that the most productive re- suits can be obtained using the compositions N. 20 (linseed oil or soy¬ bean oil with addition of diphenylamine as antioxidant), or N. 23 (lin¬ seed oil or soybean oil with addition of dried extracts from Ascophyllum type seaweeds hydrolized with alkali, which are rich in natural plant growth regulators), or even N. 24 (linseed oil or soybean oil with addi-^' tion of animal epithelium hydrolized with acids, containing 14% of orga¬ nic nitrogen), or N. 17 (soybean oil with addition of laurylgallate and of urea). These results clearly prove that such compositions - based on vegetable oils mixed with an antioxidant, or with seaweed extracts con¬ taining natural plant growth regulators, or even with a fertilizer based on organic nitrogen obtained from hydrolysis of animal epithelium - give rise to an unexpected synergic strengthening action, with the additional advantages deriving therefrom.

It is in fact remarkable how the use of the antioxidant or of the seaweeds extract or of the hydrolized epithelium, all as such - in doses corresponding to those contained in the compositions according to the invention - is not apt to increase production in respect of the un¬ treated witness plants and to reduce the percentages of leafage damage; whereas, the different mixtures have a considerably increased effective¬ ness in respect of the compositions based only on vegetable oils (Compo- sition N. 18 based on linseed oil or on soybean oil).

TABLE 6 Average percent of leafage necrosis and unitary production at harvesting time on field cultivations, in presence of harmful ozone le¬ vels and with various anti-ozone treatments repeated during the plants vegetation period.

Notes to Table 6: 1 ) = Doses of diphenylamine equivalent to those contained in composition

2 N. 20, with doses of oils equal to 0.1-1 ml/m .

2) = Doses of dried seaweed extracts hydrolized with alkali equivalent to those contained in composition N. 23, with doses of oils equal to 0.1-1 ml/m .

3) = Doses of animal epithelium hydrolized with acids equivalent to those contained in composition N. 24, with doses of oils equal to 0.1-1 2 ml/m

4) = DDoossies of urea and of laurylgallate equivalent to those contained in

2 composition N. 17, with doses of soybean oil equal to 0.1-1 ml/m

Example 11

Vegetable oils as such, or concentrated non-diluted compositions based on such oils, were distributed on an Irnerium variety wheat field, using special equipment for distributing compositions with low volume of liquid (for example, 5-50 litres per hectare). Alternatively, emulsified compositions were distributed - using more conventional equipment with high volume of liquid - in 300 litres of water per hectare. Three repeat¬ ed treatments were carried out at emergence, earing and blossom time, operating on large plots of 400 square meters (20x20 m) of land and lea- ving plots of untreated witness plants. The ozone levels detected on the field with the portable DRAEGER analyzer were, on an average, of 0.04 ppm in the morning and of 0.08 ppm in the afternoon during the period of the treatments. At harvesting time, the production in grains obtained from the differently treated plots of land was weighed. The results are repor- ted in Table 7, which shows the considerable production increase noticed on wheat as a result of the treatments with the compositions according to the invention, even if using different distribution techniques (low or high volume of liquid).

TABLE 7 Production of Irnerium variety wheat grains at harvesting time, with preventive treatments using anti-ozone compositions at emergence, earing and blossom time, carried out with different distribution techni¬ ques.

Compositions used Doses, Production in grains at ml/m harvesting time (at 13_*5 of oils of humidity) kg/100 m^"

Raw linseed oil as such • 0.5 with low volume of liquid 5

Raw soybean oil as such 0.5 with low volume of liquid 5

Composition N. 4 based on 0. 5 sunflower oil as such 5 with low volume of liquid

Composition N. 4 based on 0.5 grapestone oil as such 5 with low volume of liquid

Composition N. 21 based on 0.5 corn oil in 300 1/ha water 5

Composition N. 21 based on 0.5 rapeseed oil in 3001/ha water 5

Composition N. 21 based on 0.5 oil of different seeds ( 50% 5

soybean. 30% sunflower, 20% rapeseed) in 300 l/ha water

Untreated witness 40.2

Example 11

In a Clone 314 poplar plantation, aged 1 years, plots of one hectare each were treated twice - at intervals of 30 days, during the pe¬ riod of maximum growth of the leaves - with compositions according to the invention, operating with atomizers using a low or high volume of liquid and provided with movable tubes to convey upward the atomized mixtures.

During the period of the treatments, the portable DRAEGER analy- zer revealed, on the poplar plantation, the presence of an average ozone level of 0.05 ppm in the morning and of 0.09 ppm in the afternoon.

The results, after 30 days from the last treatment, are reported in Table 8, from which it appears evident that the treatments with the compositions according to the invention have allowed to substantially re¬ duce the fall of the leaves caused by the presence of high ozone levels, in respect of the untreated witness plots.

TABLE 8 - Average percent of fallen leaves, in presence of harmful ozone levels, on 1 years aged Clone 314 poplar trees, 30 days after the last of two treatments carried out at intervals of 3 days with the anti-ozone compositions of the invention.

Compositions used Doses Average percent l/ha of oils of fallen leaves

N. 4, based on refined soybean 100 10.2 oil distributed as such

N. 21, based on refined soybean 100 8.5 oil distributed in 900 1/ha of water

N. 26, based on emulsified raw soybean 100 6.0 oil distributed in 900 1/ha of water

Untreated witness 0•5

Claims

3V

1 ) Composition to prevent ozone damages to cultivations, charac¬ terized in that it comprises, as an active principle, fatty acids of na¬ tural origin or their salts and esters, as in particular the triglyceri- des contained in oils and fats of vegetable or animal origin.

2) Composition as in claim 1 ) , wherein the fatty acids are unsa¬ turated fatty acids.

3) Composition as in claim 2), wherein the fatty acids are se¬ lected in the group consisting of oleic, erucic, linoleic, linolenic acids.

. 4) Composition as in claim 1 ) , wherein the oils and fats of ve¬ getable origin are selected in the group consisting of oils of linseed, soybean, sunflower, cotton, corn, safflower, grapestone, sesame, peanut, rapeseed, olive, castor-oil, tall-oil. 5) Composition as in claim 1), wherein the oils and fats of ani¬ mal origin are selected in the group consisting of oils of fish, cetace¬ ans and terrestrial Mammalia.

6) Composition as in any one of claims 1) to 5), also containing one or more compounds with antioxidant activity. 7) Composition as in claim 6), wherein the proportion of antiox¬ idant is up to 20% by weight of the composition, and this is selected in the group consisting of alkylgallates; alkylcresols, alkylphenols and alkylanisoles; ascorbic and erythrorbic acids and their salts and esters; substituted hydroquinones; alkyldiamines; diarylamines; tocopherols; di- thiopropionic acid and its salts and esters.

8) Composition as in claim 6), wherein the antioxidant is lau¬ rylgallate.

9) Composition as in claim 6⁾, wherein the antioxidant is όc- tylgallate. 10) Composition as in claim 6), wherein the antioxidant is di- buty1-hydroxy-toluene.

11 ) Composition as in claim ό) , wherein the antioxidant is di- sr phenylamine.

12) Composition as in claim 6), wherein the antioxidant is an alkyl ester of ascorbic acid or of its isomer erythrorbic acid.

13) Composition as in any one of claims 1) to 6), also contain- ing one or more chelating compounds for heavy metals.

14) Composition as in claim 13), wherein the proportion of che¬ lating compound is up to 10% by weight of the composition, and this is selected in the group consisting of citric, tartaric, phosphoric acids and their salts and esters; alkylendiamino- or pentamethylen-triaminoace- tates; editronic acid and its salts and esters; heptagluconates; amino¬ acids derived from hydrolysis of animal or vegetable proteins.

15) Composition as in any one of claims 1) to 5) , also contain¬ ing natural or synthetic plant growth regulators.

16) Composition as in claim 15), wherein the proportion of plant growth regulators is up to 20% by weight of the composition, and these are selected in the group consisting of dried extracts from seaweeds hy¬ drolized with alkali, cytoquinines, auxines, gibberellines, and abscissic acid.

17) Composition as in any one of claims 1) to 5), also contain- ing fertilizers.

18) Composition as in claim 17), wherein the proportion of fer¬ tilizers is up to 50% by weight of the composition, and these are select¬ ed in the group consisting of nitrogen, phosphorous, potassium synthesis compounds, oligo-elements, chelated microelements, and natural nitrogen derivatives as hydrolized animal or vegetable proteins.

19) Composition as in any one of claims 1) to 5), also contain¬ ing surfactants and/or emulsifiers, as well as inerts.

20) Method for applying on field or tree cultivations a liquid composition as in any one of the preceding claims, characterized in that i comprises the steps of:

- possibly thinning said composition to the desired concentration, by dilution with solvents or water emulsion: - atomizing said liquid composition as such, or else its solution or emulsion, using equipment operating on ground or air means, so as to cover the sides of the leaves having stomata;

- carrying out a treatment before any ozone damages are caused to the cultivations, and repeating the treatments at intervals during the vege¬ tation period.

21) Method as in claim 20) wherein said composition is in a solid state at ambient temperature, comprising moreover the initial step of dissolving said composition into solvents. 22) Method as in claim 20), wherein said composition is distri¬ buted on the cultivations in an amount of between 0.1 and 100 litres per hectare of fatty acids, or of oils or fats of vegetable or animal origin.

23) Method as in claim 22), wherein said composition is distri¬ buted on field cultivations in an amount of between 0.1 and 50 litres per hectare of fatty acids, or of oils or fats, and preferably between 0.3 and 20 litres per hectare.

24) Method as in claim 22), wherein said composition is distri¬ buted on tree cultivations in an amount of between 0.2 and 100 litres per hectare of fatty acids, or of oils or fats, and preferably between 0.6 and 40 litres per hectare.