SYNERGISTIC TREE INJECTABLE COMPOSITION FOR TREATING FOLIAR SILVERING

Abstract: A method of treating a tree or vine exposed to a pathogenic challenge such as silverleaf pathogens, Trametes pathogens and Eutypa pathogens, which method comprises (I) injecting into the heartwood of the tree an effective amount of a triazole fungicide or (II) substantially at least simultaneously co-administering or serially administering by injection into the heartwood of the tree (A) at least one of the group comprising phosphorous acid, a salt or phosphorous acid and a bioprecursor of the anion of phosphorous acid, and (B) a triazole fungicide (e.g. cyproconazole). The invention also consists in combinations and compositions useful in such a method.

Description: "SYNERGISTIC TREE INJECTABLE COMPOSITION FOR TREATING FOLIAR SILVERING" TECHNICAL FIELD The present invention relates to improvements/compositions useful in a method of treating disease or nutrient deficiency in a tree. BACKGROUND Tree injection systems for injecting treatments into trees to control growth or diseases have been investigated since the early 1970's with varying degrees of success. Such systems have concentrated on two concepts. 1. Tree Infusion Solutions are introduced into the tree under gravity through holes in the tree or roots. The solution is drawn into the outer xylem vessels by transpiration water loss hence the process is affected by factors determining transpiration rate such as time of day and season. The solution also tends to accumulate in the leaves causing phytotoxicity and can form airlocks, embolisms in the vessels. 2. Injection of solutions under pressure A number of pressurisation techniques have or are being used to inject the solution into the tree. They are: a) Bags pressurised to approximately 70 psi using hands pumps. In this system the pressure declines as the volumes decreases. b) Spring loaded syringes. These inject small volumes (approximately 20 mis) into shallow holes around 20-30mm deep. c) Pressure cylinders using nitrogen, air or carbon dioxide at 120 psi (maximum 200 psi) to inject solution into holes 20-70mm deep. With these systems the solution blows out back through the bark if pressurised greater than 200 psi. Commonalities and limitations of these systems are: 1. They inject aqueous solutions into the sapwood of trees. 2. They all rely on the majority of the solution being taken up by the outer xylem tissue hence are dependant on transpiration pull. 3. Higher pressures (>200 psi) do not increase rate of uptake. 4. Chemicals must be water soluble or salt solutions. 5. Injection times vary from 30 seconds to 5 minutes depending on transpiration rate. 6. Current injection systems are large and cumbersome. 7. Injected solution can course phytotoxicity to leaves. RELEVANT REFERENCES Clifford D.R., Gay C.N., Gendle P. 1984, Injection for the Control of Tree Diseases. British Crop Protection Conference, 1067-1074. Gendle P., Gay C.N., Clifford D.R. 1984. Tree Injection. A Viable Method for Disease Control? British Crop Protection Conference, 955-1000. Reil W.O 1979. Pressure-injecting Chemicals into Trees. California Agriculture, June, 16-19. Sachs R.M., Nyland G., Hackett W.P., Coffelt J., Debie J., Giannini G. 1977. Pressurised Injection of Aqueous Solutions into Tree Trunks. Scientia Horticulture, 6,297-310. Brown G.K. 1978. Prototype Equipment for Commercial Pressure-Injection of Aqueous Solutions into Trees. Journal of Arboriculture 4(1) January 7-13. All the above tree injection systems target the outer xylem tissues for injecting the solution into. The proposed injection system is particularly effective at injecting solutions into central xylem tissues to control pathogens infecting these tissues such as silverleaf, Trametes and other white rot Basidiocycetes and Eutypa. CHONDROSTEREUM PURPUREUM (Silverleaf pathogen) affect predominantly fruit trees but can affect poplars and willows as well. Spores of the fungus gain entry to the trees through freshly made wounds on the trunk or branches. The toxins cause the leaves to become silvered and ultimately may kill all or part of the tree. Dye M 1972: Silverleaf Disease of Fruit Trees. New Zealand Ministry of Agriculture and Fisheries Bulletin No. 104. At present the only commercially available method for treating silverleaf is: 1. Tricho dowels - small fluted dowls impregnated with spores of Trichoderma fungus which is inserted into holes drilled in the trunks/branches of trees. Several dowels are applied to heavily silvered trees. 2. Trichoject - a liquid injectable formulation of Trichoderma injected with spring loaded syringes into 6mm diameter holes drilled 15- 100mm into trunks of silvered trees at rates of 10-20mls. Neither of these treatments are particularly effective. No chemicals are currently registered in New Zealand for the treatment of silverleaf infected trees. EUTYPA LATA is an asconycete fungus which infect pruning wounds and infect xylem tissues. Toxins are produced which start growth. The life cycle of Eutypa species is very similar to that of silverleaf. Infected trees can be treated to control this pathogen in the same way as silverleaf. Eutypa is a pathogen commonly found in apricot trees and grape vines [Carter M.V. (1991) - The status of Eutypa lata as a pathogen. Phytopathological Paper No.32 72pp Published by CAB International]. TRAMETES VERSICOLA and other Trametes spp are wound pathogens causing stem dieback. Their life cyle is similar to chondrostereum and infected trees can be treated the same way as for chondrostereum. Trametes is a major cuase of fruit tree dieback in Australia and South Africa. The disease is not a problem in New Zealand. Darbyshire B; Wade G.C. & Marshall K.C. 1969. In vitro studies of the role of nitrogen and sugars on the susceptability of Apple Wood Decay by Trametes Versicola. Phytopathology Volume 59 pages 98 - 102. DISCLOSURE OF INVENTION The present invention consists in a tree or vine (hereafter "tree") injectable composition effective by injection in treating xylem invading pathogens such as Silverleaf pathogens, Trametes pathogens, Eutypa pathogens and Basidiomycetes pathogens, said composition comprising (A) at least one of the group comprising phosphorous acid, a salt of phosphorous acid and any bioprecursor of the anion of phosphorous acid, and (B) a triazole fungicide Triazoles of interest include cyproconazole, azaconazole, tebuconazole, triadimefon, triadimenol, bitertanol, HWG 1608 ethyltrianol-terbuconazole, propiconazole, etaconazole, penconazole, diclobutrazol, flutriafol, hexaconazole, myclobutanil, flusilazole, diniconazole, epoxiconazole. Preferably (B) is or includes cyproconazole Preferably (A) and (B) are synergistic in effect. Preferably there is also present (C) a liquid carrier or diluent. Preferably (C) is or includes water. Preferably (C) is or includes methyl cellulose. Preferably (C) includes ground agar. Preferably (A) is or includes a salt of phosphorous acid. Preferably (A) is or includes phorphorous acid. Preferably the pathogenic challenge is silverleaf. Preferably. (A) comprises about 4% (g/L) when expressed as phosphorous acid and (B) comprises about 1.5% (g/L). In one aspect the composition preferably is in a tree injection apparatus. Preferably said apparatus is capable of injecting about 100 ml of the composition. In a further aspect the invention consists in a method of treating the diseases of Silverleaf, and other white rot caused by Chondrostereum, Trametes, Eutypa or Basidiomycetes fungi, in a tree or vine by stem injection of an effective amount of a triazole fungicide. Preferably said fungicide is or includes cyproconazole. In yet a further aspect the present invention consists in a method of treating a tree or vine (hereafter "tree") exposed to a pathogenic challenge (eg; selected from silverleaf pathogens, Trametes pathogens, Eutypa pathogens and Basidiomcycetes pathogens) which method comprises (I) injecting into the heartwood thereof an effective amount of a synergistic tree injectable composition as previously set forth, (II) or substantially simultaneously co-administering by injection into the heartwood of the tree A) at least one of the group comprising phosphorous acid, a salt of phosphorous acid and a bioprecursor of the anion of phosphorous acid and B) Cyproconazole. In still a further aspect the present invention consists in a method of method treating Silverleaf disease in a tree comprising stem-injection of an effective amount of a triazole fungicide seletected from azaconazole, cyproconazole and tebuconazole. Preferably said injection is by a method as disclosed in New Zealand Patent Specification No. 250474. Preferably said treatment is for reducing foliar silvering in a tree that is exposed to the prospect of foliar silvering or is suffering from foliar silvering. Preferably said injection is at a pressure in the range of from 300 to 1500 psi over a period of from about 15 to about 30 seconds. Preferably .said injection is by a method and using apparatus substantially as hereinafter described with or without reference to any of the accompanying drawings. Preferably said injection is of a composition as set forth. Preferably said injection is a serial administration of (A) and (B) in a time pacing or substantially simultaneously so as to elicit a synergistic effect. Preferably the composition comprises about 1.5% Cyproconazole and about 4% phosphorous acid (or any equivalent source of (B) and (A) compound(s) respectively in a substantially similar relative active ingredient ratio) preferably in or carried by a liquid medium selected from one or more of the group comprising water and any organic solvent. Preferably the composition is applied into trees or vines in quantities of the order of about 1ml per 2.5mm of trunk diameter for controlling Silverleaf, Trametes or Eutypa. Preferably the composition is injected into one or more two sites in a tree, eg; two. In a further aspect the invention is, in combination, (A) at least one of the group comprising phosphorous acid, a salt of phosphorous acid and any bioprecursor of the anion of phosphorous acid, and (B) a triazole fungicide (eg; cyproconazole) together with instructions to use (A) and (B) in a method of the present invention. THE PERCENTAGES The % of active ingredient in mixtures described hereafter are expressed as volume which equates to weight/weight a) e.g. 3% Cyproconazole = 300 mis of ALTO (contents: 100 g/L cyproconazole) plus 700 ml dilutent to make one litre overall. [ALTO™ (SAN619F) of Sandoz Agro of Auckland, New Zealand]. b) e.g. 8% phosphorous acid = 200 ml of FOLI-R-FOS™ (contents: 400 g/L phosphorous acid) plus 800 ml dilutent to make one litre overall. [FOLI-R-FOS™ is 400 g/litre phosphorous acid present as the mono- and di-potassium salts in the form of a concentrate available from Key Industries Ltd, Auckland, New Zealand]. ALTO™ contains the triazole cyproconazole which is an ergosterol-bisysnthesis- inhibitor (EBI) of the 14 Alpha-Demethylation-Inhibitor (DMI) type. The two mixtures A & B are combined to give 2 litres of formulation, which contains 1.5% cyproconazole and 4% phosphorous acid. BRIEF DESCRIPTION OF DRAWINGS The preferred form of the present invention will now be described with reference to the accompanying drawings in which: Figure 1 is a diagrammatic view (two ways) of a tree trunk, Figure 1A showing a preferred 6mm hole extending 80% or 90% the way through the wood of the timber while Figures 1A and Figures IB designated by references A through F the following: a) the pith b) the heartwood c) the bark d) the sapwood and e) cambium of the tree. The solutions are injected into heartwood (pith and central xylem tissue) of the tree in either aqueous solution or as a slurry (viscosity range 400-20,000 centipoise) at pressures up to 2500 psi. The normal working pressure though is usually between 300 and 1500 psi depending on the viscosity of the injected fluid, the genus and species and the time of year the tree is injected. The system works by drilling a hole into the tree to a depth that passes through the heartwood of the tree. The solution is then injected into this hole under high pressure forcing the solution both up and down the heartwood and central pith. The injection time is in the order of 15 to 30 seconds regardless of time of year which is extremely quick compared to other systems. Also the solution can be forced into the root system if the injection point is at the base of the tree. The amount of solution injected is dependant on severity of disease, the tree trunk or branch diameter, the site of injection and for what purpose. A tree may also need to be injected in more than one site. The injection technique was developed to enable treatment of hardwood trees infected with Chondrostereum purpureum (silver leaf) Eutypa lata (eutypa) and Trametes versicolor (Trametes) which colonise central xylem tissue. The following features are to be noted: 1. The solution is injected directly into the central xylem tissue (pith & heartwood) of the tree. 2. The high operating pressures needed to inject the solution (100 to 2500 psi). 3. The ability to inject solutions of different viscosity (400-20,000 centipoise). 4. The solution can be injected at any time of the day or year and is totally independent of transpiration pull. 5. The rapid injection of the solutions. Example Injection System The example system is preferably made up of three components a) a screw in adaptor (ie "the assembly"). b) an injector pump c) apressure vessel orreservoir Once the injection site or sites in the tree have been decided, a 6mm hole is drilled horizontally into the tree to a depth 80-90 percent of the diameter of the tree, deep enough to pass through the pith and heartwood of the tree (fig 1). The screw adaptor (fig 2) (ie. "the assembly") is then screwed firmly into the hole so the thread (1) and rubber (or equivalent) (2) form a seal to prevent the solution blowing out back along the thread when being injected. The pressure vessel 4 (fig 3) is filled with the appropriate solution or slurry (7) and pressurised by raising and lowering the hand pump (5) a few times. Ideally the vessel should be pressurised to between 10 and 50 psi. The outlet connecter or nozzle on the injector pump (8) is pushed onto the grease gun type nipple (3) in the tree adaptor or assembly (see fig 2). The operator then manually pumps the solution into the tree. Each time the operator opens and closes handles (10 and 11) 3ml of solution is injected into the tree. When handle (10) is lifted the piston (12) slides up the cylinder creating suction in the cylinder whereby the reservoir solution is drawn (along with the pressure in reservoir 4) into the pump. When the handles are closed the piston (12) moves down (ie. to the right with respect to fig 3) the cylinder forcing the solution through the non-return ' valve (13) through the grease gun type nipple (3) of the assembly (adaptor) and into the tree. The pump handles are opened and closed until the appropriate volume of solution has been pumped into the tree. The total time to drill the hole in the tree, screw in the adaptor, pump in the solution and unscrew the adaptor is 2-3 minutes. BEST MODE(S) FOR CARRYING OUT THE INVENTION Trials where the fungicides Cyproconazole, Azoconazole, Tebuconazole and Phosphorous acid were applied in various combinations provide the results of Tables 2 to 5. Cyproconazole and phosphorous acid have been injected into trees mixed with 1. water 2. agar ( 1.4%) ground in a blender 3. methyl cellulose 4. with glycerol - would inject but tended to run out. 5. with paraffin - would inject but tended to run out. Mixtures formulated with agar, methyl cellulose and water injected well and gave good control of silverleaf. In most of the trials methyl cellulose was used because of its ease of injection and lubricating properties. Mixtures of FOLI-R-FOS™ with FOLICUR™ (Terbuconazole) and NECTEC™ (azaconazole) did not give the same enhanced control of silverleaf as seen with cypoconazole. TRIALS WITH GOLDEN QUEEN PEACHES/FIESTA APPLES - HAWKES BAY Trials were conducted on Golden Queen peaches and Fiesta apples in Hawke's Bay, New Zealand to investigate control of foliar silvering using stem injection. The trees in the Hawke's Bay were assessed and treated for silverleaf infections in December 1992/January/February and March 1993. During late February/March 1994, the treated trees were reassessed for foliar silvering. The trees were assessed for silverleaf infection as follows: Silverleaf rating - Trees were rated using the Schreiner van der Meiden rating system (Schreiner 1959, van der Meiden 1961) originally devised for assessing poplars for Melampsora rust. This system is subjective but readily gives an assessment based on the level of foliar silvering (light, medium heavy, very heavy), and percentage of the canopy exhibiting that degree of silvering. A linear scale was added to enable statistical analysis of data (Table 1). At treatment, the trees were rated then the trunks were painted with dots, viz: • single dot = light infection •• two dots = medium infection ••• three dots = heavy infection •••• four dots = very heavy infection This marking system enables rapid identification of injected trees and assessment of recovery in subsequent years. Injected trees were revisited approximately one year following injection and re-rated for foliar silvering. For each treatment, analysis of variance (Statgraphics) was conducted between foliar silvering at treatment and one year later. See Table 2. Table 1. Rating scale for assessing ; Silverleaf infection Spots on 1 Level of 2 Percentage of Field rating 4 Rating for data trunk silverleaf foliage analysis 5 infected 3 zero zero 0 0 0 • light <50 1-2 1 >50 3-4 2 •• medium <50 5-10 3 >50 15-20 4 ••• heavy <50 25-50 5 >50 50-100 6 •••• Very heavy <33 125 7 <66 250 8 <99 375 9 100 Tree dead 10 Spots painted on trunk when tree rated and treated Light - slightly silvered leaves Medium - moderately silvered leaves Heavy - strongly silvered leaves Very heavy - leaves shrunken in size, distorted with premature leaf fall. Percentage of foliage exhibiting particular level of foliar silvering. Field rating. Linear scale utilized for analysis of variance. Table 2. Control of silverleaf on Fiesta apples and Golden Queen peaches in the Hawke's Bay with Cyproconazole and Phosphorous acid Mean Tree Rating 1 Treatment Number of At After Significance 2 Reduction in 3 Trees Treatment Treatment P < 0.05 Silvering Fiesta Apples (Hawke's Bay) 2% 20 5.6 3.2 * 42.8% Cyproconazole 8% Phosphorous 20 4.2 2.3 * 45% acid 3% Phosphorous acid + 24 5.0 1.9 * 62% 1% Cyproconazole 4% Phosphorous acid + 1.5% 16 4.8 1.0 * 79% Cyproconazole Control 24 4.5 3.8 NS 15.5% Golden Queen Peach (Hawke's Bay) 1.5% Cyproconazole 16 4.8 3.9 NS 18.3% 8% Phosphorous 61 4.3 2.7 * 37.2% acid 4% Phosphorous acid+ 16 5.1 2.4 * 53.0 0.75% Cyproconazole Control 69 4.8 5.6 NS -16.7% See linear scale Table 1 NS = No significant difference at (P < 0.05) * significant at (P < 0.05) % reduction in level of foliar silvering Table 3A. Control of silverleaf on Golden Queen peaches in the Hawke's Bay and Fiesta and Gala apples in Motueka with Cyproconazole and Phosphorous acid Mean Tree Rating 1 Treatment Number of At After Significance 2 Reduction in 3 Trees Treatment Treatment P < 0.05 Silvering Golden Queen Peach 1.5% 35 4.8 3.1 * 35.4% Tebuconazole 8% Phosphorous 61 4.3 2.7 * 37.2% acid 0.75% Tebuconazole + .55 4.9 3.3 * 33.0% 4% Phosphorous acid Control * 69 - 4.8 5.6 NS -16.7% Fiesta Apples (Motueka) 1.5% 103 6.1 4.2 * 31.7% Tebuconazole 8% Phosphorous 69 5.93 3.0 * 49.1% acid 1 % Tebuconazole 150 6.0 3.6 * 40% + 4% Phosphorous acid Control 46 5.5 5.3 NS -3.6% Gala Apples 2% Tebuconazole 20 5.7 2.9 * 48.7% 8% Phosphorous acid 20 5.9 3.7 * 37.2% 4% Phosphorous acid + 20 5.5 3.3 * 39.6% 1% Tebuconazole Control 20 5.8 4.8 * 17.2% See linear scale Table 1 NS = No significant difference at (P < 0.05) * significant at (P < 0.05) % reduction in level of foliar silvering GALA APPLE TREES TREATED FOR SILVERLEAF (CHONDROSTEREUM PURPUREUM) Treated February 1992 Assessed for silverleaf March 1993 Treatment No. Mean Rating Significance (1) Reduction Trees Tree in Silvering % (2) 6% Phosphorous acid 10 4.2 3.0 * 28.5 3% Phosphorous acid 20 4.0 3.3 NS 17.3 0.5% Cyproconazole 10 5.0 3.9 NS 22.0 ι 1.0% Cyproconazole 12 4.2 2.8 * 32.0 1 See linear scale Table 1 2 NS = No significant difference at (P < 0.05) * significant at (P < 0.05) 3 % reduction in level of foliar silvering The data shows that greatest reductions in foliar silvering were obtained when Cyproconazole and Phosphorous acid were injected in combination. The effect appeared to be independent of Cyproconazole and Phosphorous acid concentration (Table 2). For commercial treatment of fruit trees a combination of 1.5% Cyproconazole (ai) and 4% Phosphorous acid (ai) is recommended. Combination of (cyproconazole) and (phosphorous acid) gave enhanced control of silverleaf disease (Chondrostereum purpureum). Combination of a related triazole, Tebuconazole and phosphorous acid did not give the same degree of enhanced control of silverleaf. The use of Cyproconazole plus Phosphorous acid in combination is therefore recommended for tree injection to control silverleaf infection. References Schreiner, E.J. 1959: Rating poplars for Melampsora rust infection. Forestry Research Notes, Northeast Experimental Station 90. Van der Meiden, H.A. 1961: Methods for rating leaf rust infection of poplar. Nederlands Bosbouw Tydschrift 33 (3): 77-80. TRIALS INVESTIGATING CONTROL OF SILVERLEAF IN GRAFTED OVER APPLES - CHRISTCHURCH Grafting-over of reverted Gala or less favoured cultivars is a useful technique for renewing stock without replanting and minimal loss of production. The major problem with the technique however is the extensive foliar silvering exhibited by grafts. This can cause rejection of the graft or stunted growth and delayed fruit production. Five year old Gala apples growing at Christchurch were injected (at two sites in each tree), using the aforementioned tree injection system. The trees had been overgrafted the previous winter with Braeburn and were severely silvered (mean rating 4.1), when treated. The trees were rated for foliar silvering during March 1993. The trees were treated 4-5 August 1993 with 8% Phosphorous acid; 3% Cyproconazole and 4% Phosphorous acid + 1.5% Cyproconazole. Treated trees were revisited 9 months later (7 April 1994) and re-rated for foliar silvering. The rating system used is detailed in Table 1. For each treatment silverleaf rating at treatment and 9 months later were compared and analysed for significant differences (PO.05) (Statgraphics). Results The results obtained are summarised in Table 4. All treatments apart from the untreated control gave significant control of foliar silvering. Untreated trees exhibited a 21% reduction in foliar silvering. Combination of 1.5% Cyproconazole + 4% Phosphorous acid gave enhanced recovery (75%) in comparison to 3% Cyproconazole (56%) and 8% Phosphorous acid (53%). Discussion Foliar silvering in grafts is expressed as a result of cutting the parent trees back which exacerbates expression of latent silverleaf infection within xylem tissues. This is clearly demonstrated when Red Delicious trees are grafted. Intact Red Delicious trees rarely express foliar silvering. However, when cut back or grafted, the regrowth and/or grafts are invariably silvered. Grafting or Granny Smith and Gala also results in extensive foliar silvering. This trial has shown that recovery of the grafts is enhanced by treatment of grafted trees. This should be done as standard practice at the time of grafting. Best reduction of silvering within the grafts was obtained by treatment with Cyproconazole + Phosphorous acid. Untreated trees do recover but recovery is erratic. Table 4. Treatments applied to grafted over Gala Apples and results obtained at Johns Road. Treatment No. of Mean tree rating 1 Significance Reduction Trees At treatment 1 yr in later Silvering 3 8% Phosphorous acid 34 4.5 2.1 * 53% 3% Cyproconazole 32 3.3 1.4 * 56% 4% Phosphorous acid 32 4.5 1.1 * 75% + 1.5% Cyproconazole 33 3.8 3.0 NS 21% Control See linear scale Table 1 NS = No significant difference at (P < 0.05) * significant at (P < 0.05) % reduction in level of foliar silvering Table 5. (i) Golden Queen Peaches, Hastings, L Hill Property Treated 26/1/94 - Assessed 19/1/95 Treatment No. of Mean tree rating Significance 1 Reduction Trees At treatment 1 yr in later Silvering 2 3% Cyproconazole 27 5.44 3.60 * 34.0% 8% Phosphorous acid 12 6.00 5.20 NS 15.0% 1.5% Cyproconazole + 35 4.50 2.20 * 51.6% 4% Phosphorous acid 1 See linear scale Table 1 2 NS = No significant difference at (P < 0.05) * significant at (P < 0.05) 3 % reduction in level of foliar silvering Observations: In this trial combination gave enhanced control. (ii) Golden Queen Peaches, Hawkes Bay, Apatu Treated 13-16/12/93 - Assessed 10/2/95 Treatment No. of Mean tree rating Significance 1 Recovery 2 Trees At treatment 1 yr later 8% Phosphorous acid 29 5.0 4.4 NS 11.8% 3% Cyproconazole 45 5.2 4.0 NS 23.1% 1% Cyproconazole + 4% Phosphorous acid 23 4.5 2.4 * 45.6% 1.5% Cyproconazole + 5% Phosphorous 14 4.1 2.3 * 43.8% acid 1.5% Cyproconazole 39 4.4 3.0 * 31.2% + 4% Phosphorous Acid -. See linear scale Table 1 2 NS = No significant difference at (P < 0.05) * significant at (P < 0.05) % reduction in level of foliar silvering Observations: Varying concentrations of Cyproconazole + phosphorous acid gave enhanced control. (ii) Golden Queen Peaches, Hawkes Bay, H McPhail Treated 24/3/94 - Assessed 16/1/95 Treatment No. Mean tree rating Significance 1 Recovery 2 of At treatment 1 yr Trees later 8% Phosphorous Acid 20 5.1 4.1 NS 18.6% 1.5% Cyproconazole E.C. + 4% 20 5.0 3.2 * 35.3% Phosphorous Acid 1.5% Cyproconazole S.L. + 4% 17 4.8 3.1 * 36.6% Phosphorous Acid 3% Azaconazole 21 6.1 5.1 NS 17.0% 1.5% Azaconazole + 16 4.7 4.2 NS 10.5% 4% Phosphorous Observations: EC + SL formulation of Cyroconazole worked equally as well. Azaconazole performed less effectively when mixed with Phosphorous Acid. E.C. = Emulsifiable Concentrate S.L. = Soluble Liquid SYNERGISTICFORMULATIONFORCONTROLOFCHONDROSTEREUM PURPUREUM,TRAMETESANDEUTYPALATA Method: 10mm plug of growing fungus were placed in agar in 85mm diam petri dish. A 10mm drop of liquid synergistic formulation (1.5% cyproconazole + 4% phosphorous acid) was placed on malt agar at the opposite side of petri dish to fungus. The plates were incubated at 20°C for 10 days. Results Percentage inhibition of fungus growth Fungus Treatments 1.5% Cyproconazole Untreated + 4% Phosphorous Acid Control Chondrostereum 100% 0% Purpureum (Silverleaf) Trametes Versicolor 100% 0% (Trametes) Eutypa lata 100% 0% (Eutypa) 100% = zero growth of fungus. 0% = whole peti dish filled with fungus. Conclusion: formulation of 1.5% cyproconazole + 4% phosphorous acid completely inhibited growth of Chondrostereum, Trametes and Eutypa

Claims: WHAT WE CLAIM IS: 1. A tree or vine (hereafter "tree") injectable composition effective by injection in treating a xylem invading pathogen, (eg silverleaf pathogens, trametes pathogens, eutypa pathogens and/or basidiomycetes pathogens), said composition comprising or including (A) at least one of the group comprising phosphorous acid, a salt of phosphorous acid and any bioprecursor of the anion of phosphorous acid, and (B) a triazole fungicide. 2. A composition of claim 1 wherein (B) is cyproconazole. 3. A composition of claim 1 or 2 wherein there is also present (C) a liquid carrier or dilutent. 4. A composition of claim 3 wherein (C) is or includes water. 5. A composition of claim 3 or 4 wherein (C) is or includes methyl cellulose. 6. A composition of any one of claims 3 to 5 wherein (C) includes ground agar in suspension with H 2 0 as a gel. 7. A composition of any one of the preceding claims wherein (A) is or includes a salt of phosphorous acid. 8. A composition of any one of claims 1 to 6 wherein (A) is or includes phorphorous acid. 9. A composition of any one of the preceding claims wherein (A) comprises about 4% (g/L) when expressed as phosphorous acid and (B) comprises about 1.5% (g/L). 10. A composition of any one of the preceding claims when in a tree injection apparatus. 11 A composition of claim 10 wherein said apparatus is capable of injecting about 100 ml of the composition. 12. A composition of any one of the preceding claims capable of and for synergisticly treating a tree subject to foliar silvering or exposed to the prospect of foliar silvering or growth inhibition (for example by Trametes, Eutypa and/or Basidiomycetes). 13. A method of treating the diseases of Silverleaf, and other white rot caused by Chondrostereum, Trametes, Eutypa or Basidiomycetes fungi, in a tree or vine by stem injection of an effective amount of a triazole fungicide. 14. A method of claim 13 wherein said fungicide is or includes cyproconazole. 5 15. A method of treating a tree or vine (hereafter "tree") exposed to a pathogenic challenge as claimed in claim 13 or 14 which method comprises (I) injecting into the heartwood of the tree an effective amount of a tree injectable composition as claimed in any one of the preceding claims, (II) or substantially simultaneously co-administering or serially administering by 10 injection into the heartwood of the tree A) at least one of the group comprising phosphorous acid, a salt of phosphorous acid and a bioprecursor of the anion of phosphorous acid, and B) a triazole fungicide. 16. A method of claim 15 wherein (B) is cyproconazole. « 15 17. A method as claimed in any one of claim 13 to 16 wherein said treatment is for reducing foliar silvering in a tree that is exposed to the prospect of foliar silvering or is suffering from foliar silvering or growth reduction. 18. A method as claimed in any one of claim 13 to 17 wherein the composition is applied into the tree in a quantity of the order of about 1ml per 2.5mm of trunk 20 diameter. 19. A method as claimed in any one of claims 13 to claim 18 wherein the composition is injected into at least two sites in the tree. 20. A method as claimed in any one of claims 13 to 19 wherein said injection is at a pressure in the range of from 300 to 1500 psi over a period of from about 15 to about 25 30 seconds. 21. A method as claimed in any one of claims 13 to 20 wherein said injection is by a method and using apparatus substantially as hereinbefore described with or without reference to any of the accompanying drawings. 22. A method as claimed in any one of claims 13 to 21 wherein said injection is of a 30 composition as claimed in any one of claims 1 to 12. 23. A method as claimed in any one of claims 13 to 22 wherein said injection is a serial administration of (A) and (B) in a time spacing or substantially simultaneously so as to elicit a synergistic effect. 24. In combination 5 (A) at least one of the group comprising phosphorous acid, a salt of phosphorous acid and any bioprecursor of the anion of phosphorous acid, and (B) a triazole fungicide together with instructions to use (A) and (B) in a method as claimed in any one of claim 13 to 23. 10 25. A combination of claim 24 wherein (B) is cyproconazole 26. A method of treating silverleaf disease in a tree comprosing stem-injection of an effective amount of a triazole fungicide selected from azaconazole, cyproconazole and tebuconazole. 27. A method of claim 26 wherein said injection is by a method of NZ Patent 15 Specification 250474.

Inventors: SPIERS ADRIAN GALE, WARD BRIAN GREGORY, SPIERS, ADRIAN, GALE, WARD, BRIAN, GREGORY
Applicants: HORTICULTURE AND FOOD RESEARCH, SPIERS ADRIAN GALE, WARD BRIAN GREGORY, SPIERS, ADRIAN, GALE, THE HORTICULTURE AND FOOD RESEARCH INSTITUTE OF NE, WARD, BRIAN, GREGORY
Application year: 1995
Main classification: A01N43
IPC codes: A01N43, A01N59