AU654656B2 - Composition for preserving plants - Google Patents

Description

WO 91/03159 PCT/AU90/00383 -1- COMPOSITION FOR PRESERVING PLANTS FIELD CF THE INVENTION This invention relates to compositions for preserving plants, and methods for preserving plants.

BACKGROUND OF THE INVENTION It has previously been found that the natural appearance and strength of plants and parts thereof may be extended by immersing the roots or freshly cut stems in an aqueous solution which contains glycerol, one or more dyes, one or more inorganic salts and an organic acid such as citric acid. An example of such treatments is United States Patent Number 4243693 in the name of Nordh and Svensson. For certain plant species such as conifers it has been reported that methanol or ethanol as a further solution additive may confer further useful properties. This is the case in United States Patent Number 4278715 in the name of Romerosier and Webb where combinations of monohydric alcohols and di or tri hydric alcohols are used.

Whilst prior art compositions offer promising performance there are some technical and commercial limitations of such compositions. For example, certain palms when treated with such prior art solutions exhibit bleeding. Bleeding is a phenomenon where the leaves of treated plants exhibit a leaching of dye into water droplets that form on the leaf surface.

Water droplets that form as a result of atmospheric condensation it appropriate temperature and humidity regimes. Prior art compositions have also been found to have limitations with certain Australian flora such as Acacia and Eucalyptus.

WO 91/03159 PCT/AU90/00383 -2- It is an object of the present invention to provide plant preserving compositions that overcome some of the limitations of prior art compositions or at least provide alternative preserving compositions.

SUMMARY OF THE INVENTION This invention provides in one form an aqueous solution for preserving plants wherein the solution comprises a water soluble dye, an inorganic salt and4 polyol wherein at least a portion of the polyol is selected from water soluble polyols having at least five hydroxyl groups present on each polyol molecule.

Preferably the polyol having at least five hydroxyl groups present on each polyol molecule is selected from the group consisting of sorbitol and mannitol, and most preferably the polyol is sorbitol.

Preferably the polyol comprises a combination of polyols.

Preferred combinations of polyols are glycerol and sorbitol; sorbitol and poly (ethylene glycol), and; glycerol, sorbitol and poly (ethylene glycol).

In an alternative form the invention provides a method of treating plants with the solution defined above by immersing freshly cut stems of plants into the preserving solution.

It will be appreciated that whilst the invention is directed towards aqueous solutions in a form suitable for the treatment of plants, for transport and storage reasons it may be desirable to prepare concentrated solutions that have minimum amounts of water present.

Before use these concentrated solutions are diluted with appropriate quantities of water.

Species of plants that are particularly suitable to treatment are Acacia and Eucalyptus.

Dyes that are useful for the present invention are water soluble dyes for preserving plants described in the prior art. Suitable concentrations are also adequately described in the prior art. Preferred dyes are Edicol Blue, Fast Green, Tartrazine, Amaranth, Erythrosine, Ponceau 4R. These dyes are further identified as follows: WO 91/03159 PCT/AU90/00383 -3- Edicol blue F, D C No. Cl No.

Tartrazine Yellow Blue No. 1 42090 Sunset Yellow Yellow No. 5 19140 Amaranth Red Red No. 9 16185 Ponceau 4R Red Red No. 7 16255 Erythrosine Red No. 3 45430 Fast Green Green No. 3 42053 The types levels and functions of the inorganic salts suitable for the present invention are described in the prior art.

The invention will be further described by reference to preferred embod;ments described in the examples below. In these examples all parts are expressed as parts by weight.

EXAMPLE 1 Aqueous solutions were prepared by mixing the constituents set out below.

Comp'n Water Dye+ Glycerol PEG* Sorbitol** NaNo 4 KnO 3

K

A 79.3 0.2 20 0.2 0.2 0.1 B 69.3 0.2 20 10 0.2 0.2 0.1 C 79.3 0.2 10 10 0.2 0.2 0.1 D 89.3 0.2 10 0.2 0.2 0.1 E 89.3 0.2 10 -0.2 0.2 0.1 F 69.3 0.2 15 15 0.2 0.2 0.1 Tartrazine Poly (ethylene glycol) MW 200 70% w/w aqueous solution WO 91/03159 PCT/AU90/00383 -4- EXAMPLE 2 Small cuttings of Acacia (Cootamundra) in flower were treated in solutions A-F as follows.

A test plant was cut at the stem above the root line, and then recut whilst immersed in water. After recutting, the test plant was immersed in the test solution at 200C and allowed to stand for 48 hours with the surrounding ambient conditions having a relative humidity of 40% and good atmospheric air circulation.

It was found that all test solutions had preserved the test plants but that plants preserved with solutions A, B and E exuded sap from woody section of the plants, whilst those preserved with solutions C, D and F did not exhibit this defect. It was also noted that preservation was effected most rapidly with Composition D.

EXAMPLE 3 Solutions A-F were evaluated for preserving, green bamboo, palms (Washingtonia) and Eucalyptus (Perriniana). The test method used was as set out in Example 2. When preserved plants were evaluated for bleeding resistance in a humid atmosphere, it was found that plants preserved with solutions B, D and F significantly reduced bleeding which was particularly evident for the palm and bamboo.

These Examples illustrate the benefits of the present invention. It should be noted that whilst the use of sorbitol as the sole polyol leads to non-bleeding compositions, the leaves of plants treated in this way may lack suitable flexibility and in practice a combination of glycerol and sorbitol achieve useful results. It is unknown as to why compositions of the present invention confer the above advantageous properties. However, without limiting the scope of the present invention, it is believed the presence of a polyol that tends to crystallise at ambient temperatures or above introduces sufficient structure into the treated WO 91/03159 PCT/A U90/00383 plant to prevent bleeding. It is believed that high molecular weight polyols with molecular weight above about 500 are not appropriate as they result in inadequate transport of sufficient polyol to the leaves of the plants. They may also cause blocking of the passageways within the plant stem. Cost consideration and performance indicate that sorbitol is the preferred polyol with at least five hydroyls. However mono and polysaccharides may also have useful application in the present invention.

Since modifications within the spirit and scope of the invention may be readily effected by persons skilled in the art, it is to be understood that the invention is not limited to the particular embodiment described, by way of example, hereinabove.

Claims (10)

1. A composition for preserving plants comprising solution of a water soluble dye, an inorganic salt and a water soluble polyol wherein at least a portion of the polyol is selected from polyols having at least five hydroxyl groups present in each polyol molecule.

2. A composition as defined in Claim 1 where in the polyol having at least five hydroxyl groups present on each polyol molecule is selected fromr the group consisting of sorbitol and mannitol.

3. A composition as defined in Claim 2 where the polyol is sorbitol.

4. A composition as defined in Claim 1 wherein a portion of the polyo is selected from molecules having up to four hydroxyl groups per molecule and the remainder of the polyol is selected from molecules having at least five hydroxyl groups per molecule.

A composition as defined in claim 4 where in polyols are combinations of glycerol and sorbitol, sorbitol and poly (ethylene gylcol), or sorbitol, glycerol and poly (ethylene glycol).

6. A method of treating plants by immersing a cut stem of a plant into a solution as defined in any one of Claims 1 to

7. A method of treating plants as defined in Claim 6 wherein the plants are from species Acacia, Eucalyptus, Thryptomene, Gypsophilla, Banksia, Boronia, Umonium, Heuadendron, Status and Kanagraroopas.

8. A method of treating plants as defined in Claim 7 where in plants are from species Acacia and Eucalyptus. 1 1 41 1 1 J, j A-1 Al .IL V 1.L U International Application No. PCT/AU 90/00383 I. CLASSIFICATION OF SUBJECT MATTER (if several classification symbols apply, indicate all) 6 According to International Patent Classification (IPC) or to both National Classification and IPC Int. Cl. A01N 3/00 II. FIELDS SEARCHED Minimum Documentation Searched 7 Classification System Classification Symbols IPC A01N 3/00 Documentation Searched other than Minimum Documentation to the Extent that such Documents are Included in the Fields Searched 8 AU IPC as above III. DCUMENTS CONSIDERED TO BE RELEVANT

9 Category* Citation of Document, with indication, where appropriate, Relevant to of the relevant passages 12 Claim No 13 X,Y Patents Abstracts of Japan, C-606, page 157, JP,A, 1-60660 (1,6) (MITSUI TOATSU CHEM INC) 3 July 1989 (03.07.89) See abstract X GB,A, 2110518 (ERDOKMIA ERDOGAZDASAGI VEGYI ES IPARI VALLALAT) (1) S22 June 1981 (22.06.81) See page 2, lines 8-27, lines 67-80, Slines 95-99; examples; claims 3 and Y GB,A, 1345091 (ARTHUR EDWARD BROCKIS) 30 January 1974 (30.01.74) (1) See claims 4,7 and 20; example at page 4, lines 23-31 I I SY AU,B, 60646/86 (595521) (SELLEGAARD 5 February 1987 (1,6) (05.02.87) See pages 6-7 and claims 1-18 SY US,A, 3895140 (SHELDON C.P. et al) 15 July 1975 (15.07.75) (1,6) See column 3, lines 35-47; column 4, lines 28-34; example 11 (contd) Special categories of cited documents:

10 Later document published after the international filing date or priority date document defining the general state of the and not in conflict with the application but art which is not considered to be of cited to understand the principle or theory particular relevance underlying the invention earlier document but published on or document of particular relevance; the after the international filing date claimed invention cannot be considered novel document which may throw doubts on priority or cannot be considered to involve an claim(s) or which is cited to establish the inventive step publication date of another citation or document of particular relevance; the other special reason (as specified) claimed invention cannot be considered to document referring to an oral disclosure, involve an inventive step when the document use, exhibition or other means is combined with one or more other such document published prior to the documents, such combination being obvious to international filing date but Later than a person skilled in the art. the priority date claimed document member of the same potent family IV. CERTIFICATION SDate of the Actual Completion of the Date of Mailing of this International SInternational Search I Search Report I 25 October 1990 (25.10.90) 1 7&Nqem o b i 0, International Searching Authority I Signature of Authorized Officer Australian Patent Office IDRUS Internationl App ation 1No. PCT/AU 90/00383 FURTHER. INFORMATION CONTINUED FROM T!J SECOND SHEET Y Y US,A, 3719515 (DEGGINGER) 6 March 1973 (06.03.73) See column 5, line 30 to column 6, line 9 and claim 8 Chemical Abstracts, volume 100, no.9, issued 1984, 27 February (Columbus, Ohio, Royo Fontanals, 'Long-term Preservation of Complete Natural Plants' see page 356, column 2, the abstract no. 65311e, ES 504,662 (1) I (1,6) I V. OBSERVATIONS WHERE CERTAIN CLAI RE FOUND UNSEARCHABLE 1 This international search report has not been established in respect of certain claims under Article 17(2)(a) for the following reasons: Claim numbers because they relate to subject matter not required to be I searched by this Authority, namely: Claim numbers because they relate to parts of the international application that do not comply with the prescribed requirements to such an extent that no meaningful international search can be carried out, specifically: Claim numbers because they are dependent claims and are not drafted in accordance with the second and third sentences of PCT Rule 6.4 VI. OBSERVATIONS WHERE UNITY OF INVENTION IS LACKING 2 SThis International Searching Authority found multiple inventions in this international application as follows: I .1 3 2.C I I 3 As all required additional search fees were timely paid by the applicant, this international search report covers all searchable claims of the international application. As only some of the required additional search fees were timely paid by the applicant, this international search report covers only those claims of the international application for which fees were paid, specifically claims: No required additional search fees were timely paid by the applicant. Consequently, this international search report is restricted to the invention first mentioned in the claims; it is covered by claim numbers: S4. 3 As all searchable claims could be searched without effort justifying an additional fee, the International Searching Authority did not invite payment of any additional fee. Remark on Protest The additional search fees were accompanied by applicant's protest. No protest accompanied the payment of additional search fees. Form PCT/ISA/210 (supplemental sheet (January 1985) ANNEX TO THE INTERNATIONAL SE'RCH REPORT ON INTERNATIONAL APPLICATION NO. PCT/AU 90 00383 This Annex lists the known publication level patent family members relating to the patent documents cited in the above-mentioned international search report. The Australian Patent Office is in no way liable for these particulars which are merely given for the purpose of information. Patent Document Cited in Search Report Patent Family Members AU 60646/86 BE 905187 CH 671675 CN 86106183 DE 3625348 DK 3677/86 ES 548103 ES 8700012 FR 2585538 GB 8618255 GB 2178294 JP 62089601 NL 8601825 NO 862987 NZ 217059 SE 8603272 US 4710394 FR 2589324 ES 549968 ES 8704069 US 3719515 DE 2136671 GB 1309178 US 3676169 GB 2110518 AT 1635/82 DE 3215654 FR 2504357 IT 1151748 JP 57181004