FR2780972A1 - New 4-alkyl-gamma-lactone derivatives that stimulate plant growth and defense and have antifungal activity against pathogenic fungi - Google Patents

Abstract

4-Alkyl-gamma-lactones (I) are new. 4-Alkyl-gamma-lactones of formula (I) are new: R1, R4 = H, alkyl, alkenyl, aralkyl or aralkenyl, provided that one is (CH2)nCH3; n = 0-19; R2, R3, R5, R6 = H, alkyl, alkenyl, aralkyl or aralkenyl. An Independent claim is also included for (I)-producing Trichoderma strains.

Description

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  ALKYL-GAMA-LACTONES WITH PHYSIOLOGICAL PROPERTIES

  STIMULANTS AND PHYTOSANITARIES IN AGRICULTURAL APPLICATIONS

DESCRIPTION

  The invention relates to alkyl-gamma-lactones capable of both

  to stimulate the growth and defense of plants and to exert an anti-fungal activity against pathogenic fungi by applying

  It is known that many plants and their seeds can be attacked, during the germination phase and during their development, by fungi which are present in the soil, Pythium

  notably, or in the air, Botrytis in particular. When plants are attacked by a fungal complex comprising several species of Pythium, this usually results in a decay of the latter.

  In the case of cucumber, the major pathogenic effect is manifested by seedling loss and root loss. Crops, especially market gardening, representing a very important economic market15, effective protection against

  pathogenic fungi has been researched for many years.

  Since ecological factors must be taken into account, research has focused on products of natural origin such as, for example, strains of Trichoderma mushrooms suitable for use as an agent.

  anti-fungal against soil parasitic fungi or airborne.

  The alkyl-delta-daltones, produced either by new strains of Trichoderma, or by chemical synthesis, also did

  subject of research and applications in the fields of stimulation

  tion of plant growth and defense and phytosanitary.

  Unfortunately these are unstable and require processes

  specific synthesis which lead to a significant production cost.

  As a basic document dealing with alkyl-delta-lactones, mention may be made of patent FR-2700542 which develops an action spectrum on only

three pathogens.

  While the depositor claims a completely new synthetic route with a much broader spectrum of actions on a product

different (alkyl-gamma-lactones).

  -2- As basic documents dealing with alkyl-gamma-lactones, mention may be made of: - patent EP-0133878 which does not claim the same trichoderma clones nor the same production of alkyl-gamma-lactones by their clone of

  trichoderma; 5 - patent EP-0356291 which claims bioproduction by microorganisms all different from trichoderma.

  The alkyl-gamma-lactones produced are only used in food and non-plant health applications. The depositor therefore explored new ways in order to obtain molecules:

- stable;

  - easy to produce by optimizing known chemical syntheses; effective both for stimulating plant growth and defense and for exerting anti-fungal activity against pathogenic fungi, thereby reducing the cost of producing crops and obtaining better yields;

- obtained by biosynthesis.

  Excellent results have been obtained with the alkyl-gamma-lactones which are found in certain plants and micro-organisms and which are used today only for their flavoring properties and

non phytosanitary.

  The present invention relates to alkyl-gamma-lactones of the genus having the general formula:

2 5

0 R

  in which R represents a group (CH2) n-CH3 in which n is a

  whole number between 0 and 19, preferably between 5 and 14.

  They present, either in their enantiomeric form or in their racemic form, an activity stimulating growth and defense

  plants and anti-fungal activity with respect to pathogenic fungi

  genes are maintained when we add to the previous general formula

  at least one of the substituents R2 to 46, of the alkyl or alkenes, aroma-

  -3- ticks or not, according to the general formula: R2

R6 R5

O R4

  In particular, the phytosanitary activity of the alkyl-gamma-lactones according to the invention is exerted with regard to the following pathogenic fungi:

  ALTERNARIA, APHANOMYCES, ARMILLARIA, ASCHOCHYTA, ASPERGILLUS, BOTRYTIS,

  COLLETOTRICHUM, CORYNEBACTERIUM, CORYNEUM, CERATOCYSTIS, DIDYMELA, EUTYPA,

  ERWINIA, FUSARIUM, GUANNANOMYCES, MONILIA, OIDIUM, PENICILLIUM, PHOMA,

  PERONOSPORALE, PHOMOPSIS, PHRAGMYDIUM, PHYTOPHTORA, PSEUDOMONAS, PUCCINIA,

  PYRENOCHAETA, PYRICULARIA, PHYTHIUM, RHIZOCTONIA, RHIZOPUS, ROSELLINIA,

  SCLEROTINIA, SEPTORIA, STEREUM, TILLETIA, THIELAVIOPSIS, VERTICILLIUM,

XANTHOMONAS.

  Among the possible chemical synthesis routes, we cite below, by way of nonlimiting example, that making it possible to prepare the compounds of the formula by simple isomerization reaction of a monounsaturated or mono-hydroxylated carboxylic acid in presence of an isomerization agent such as sulfuric acid, trifluoroacetic acid,

  methanesulfonic acid and "Amberlyst 15" sulfonic resin.

  In practice, we have proceeded as follows.

  In a reactor containing 200 g of 90% oleic acid and 100 ml of solvent,

  100 ml of 94% sulfuric acid are added dropwise.

  The reaction mixture is brought to 80 and kept stirring for 3 hours then cools. The mixture is taken up with 300 ml of solvent

  and washed several times with salt water saturated with NaHC03 until pH7.

  The organic phase is collected and left in the cold.

  Tetradecyl-4-butyrolactone then mass crystallizes.

  The operation yield is 44%.

  Among the possible biological routes, we cite below, by way of nonlimiting example, that making it possible to produce the compounds of the formula from microorganisms such as the fungi of the family Trichoderma. In particular, the Trichoderma strain, different from that deposited below, has been recognized as capable of producing gamma-deca-lactone (Leobardo Serrano and Coll Biotechnol Prog, 1997,13,205-208). However, this molecule is described as being at the origin of food flavoring.

of the "coconut" type.

  These molecules are probably at the origin of the effect obtained on the

  plants by lower organisms capable of producing it.

  Among the possible phytosanitary applications, we cite below, by way of nonlimiting example: - A root application against the problems of Fusarium oxysporum of tomato in soil-less culture: the active material is applied to

  variable doses from 100 g to 1 kg per hectare.

  The course of the disease is stopped 100%.

  The product is applied by irrigation water.

  - An aerial application against the problems of Botrytis cinerea (for-

  bites) of the grape clusters: the active ingredient is applied to

  variable doses of IOOg to 200 g per hectare.

  The disease is stopped for 4 weeks.

  The product is applied by sprayer to 100 liters of water per hectare.

  Gamma-lactones have been shown to induce peroxidase production in the plant. This enzyme has caused lignin synthesis

  which helps prevent attacks from pathogens. So it's a phyto-

alexine.

  In addition, the lactone acts directly against the germination of Botrytis.

  The Trichoderma strain which allowed the obtaining of the alkyl-

  gamma-lactone was deposited on 04.05.95 under the number I-1571 near the National Collection of Cultures of Microorganisms held by the Institut Pasteur (under the name PRE l). It is Trichoderma harzianum.

  The invention also relates to any stimulating composition of the

  sance and defense of plants and anti-fungal against fungi

  pathogenic genes, which includes at least one possible alkyl-gamma-lactone-

  in combination with any suitable vehicle.

  Of course, the invention is not limited to those of its embodiments, embodiments and applications which have just been described. On the contrary, it embraces all the variants that can come to the mind of a person skilled in the art in the matter, without departing from the framework,

  nor the scope of the present invention.

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Claims (7)

RVENDICATIONS   1- Alkyl-gamma-lactones characterized in that they have the general formula: 2 5 0 R   in which R represents a group (CH2) n-CH3 in which n is a   whole number between 0 and 19, preferably between 5 and 14, which   the alkyl-gamma-lactones present, either in their enantiomeric form or in their racemic form, both an activity stimulating the growth and defense of plants and an anti-fungal activity   with respect to pathogenic fungi.   2- Alkyl-gamma-lactones, according to claim 1, characterized in that the activity stimulating the growth and defense of plants and the antifungal activity with respect to pathogenic fungi are maintained when added to the preceding general formula at least one of the substituents R2 to R6, of alkyl or alkenes types, aromatic or not, according to the general formula: R2 R X R5 O R R4   3- Alkyl-gamma-lactones according to claim 1 or the claim   tion 2, characterized in that their antifungal activity is exerted with respect to at least one of the following pathogenic fungi: ALTERNARIA, APIIANOMYCES, ARMILLARIA, ASCHOCHYTA, ASPERGILLUS, BOTRYTIS,   COLLETOTRICHUM, Corynebacterium, Coryneum, CERATOCYSTIS, DIDYMELA, Eutypa Erwinia, Fusarium, GUANNANOMYCES, Monilia, powdery mildew, Penicillium, PIIOMA, PERONOSPORALE, PHOMOPSIS, PHRAGMYDIUM, PHYTOPIITORA, Pseudomonas, PUCCINIA, 30 Pyrenochaeta, Pyricularia, Pythium, Rhizoctonia, Rhizopus Rosellinia ,   SCLEROTINIA, SEPTORIA, STEREUM, TILLETIA, THIELAVIOPSIS, VERTICILLIUM, XANTHOMONAS.   4- Composition stimulating the growth and defense of plants and anti-fungal against pathogenic fungi, characterized -7-   in that it comprises at least one alkyl-gamma-lactone, according to the claim   cation 1 or claim 2, optionally associated with any suitable vehicle. 5- Trichoderma strains characterized in that they produce alkyl-gamma-lactones, according to claim 1 or claim 2, capable both of stimulating the growth and the defense of plants and   to exert an antifungal activity with respect to at least one of the pathogenic fungi according to claim 3.   6- Trichoderma strain, according to claim 5, characterized   in that it is a Trichoderma harzianum, called PRE 1.   7- Trichoderma strain, according to claim 6, characterized in that it was deposited, on 04.05.95 under the number 1-1571, with the National Collection of Cultures of Microorganisms held by the Pasteur Institute.