NZ501984A - Fungicidal and bacterial (kocide-cupric hydroxide) compositions selected from Fe-EDDHA (ethylene-diamine di-O-hydroxyphenylacetate), Cu-EDDHA, Mn-EDDHA and Zn-EDDHA - Google Patents

Abstract

A composition containing fungicidal and bactericidal effective amounts of heavy metal chelates such as manganese, zinc, iron, tin, copper and combinations thereof, in an aqueous solution. The chelate being a member of the EDDHA family, preferably in the form of Cu-EDDHA (cupric ethylene diamine diohydroxyphenylacetate). Such compositions control fungal and bacterial attacks on plants.

Description

1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 FUNGICIDAL AND BACTERICIDAL COMPOSITIONS FOR PLANTS CONTAINING COMPOUNDS IN THE FORM OF HEAVY METAL CHELATES FTETJ) OF THE INVENTION The present invention is broadly concerned with fungicidal and bactericidal compositions, and methods of use, which provide improved efficacy in controlling parasitic fungi and bacterial infections in plants. More particularly, the compositions and methods of use of the invention including fungicidally and bacterially effective amounts of copper compounds in form of heavy metal chelates, and preferably in the form of Cu-EDDHA, cupric ethylene diamine dio-hydroxyphenylacetate in aqueous solution).

BACKGROUND OF THE INVENTION Fungicides, as well as bactericides, are chemical agents used to protect agricultural crops from those pathogens which, if left uncontrolled, would result in unacceptable economic losses.

Copper compounds that are active as fungicides and bactericides have been in agricultural use since the advent of Bordeaux in the grape vineyards of France in the early 1800's. Many different formulations of fungicides employing copper compounds, such as wettable powders, water based flowables and dry flowables, are commonly used today in modern agricultural applications.

Cr ' j C-:.*7 L j 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 22 23 Such copper compounds, for the most part, have been inorganic in form when applied to agricultural uses Organic forms of the copper compounds have been found to be generally phytotoxic, especially in foliar applications. (Certain organic copper compounds, however, have some utility as fungicides (e.g., CTJTRINE Cu salt of triethanole amine) is quite effective as an aquatic algaecide.) Modern day agricultural use of inorganic copper compounds as fungicides employ varying forms of copper compounds having relatively low water solubility, including for example, cupric hydroxide, tri basic copper sulfate and tank mix combinations (with heavy metal ethylene bis dithiocarbamate fungicides to enhance the bactericidal activity against certain important agricultural bacteria such as Xanthomonas, Pseudomonas, and Erwinia).

Water soluble copper compounds such as CuS04, though effective to inhibit germination of fungus spores, cannot be used m foliar applications to agricultural crops because the cupric ion is extremely phytotoxic Therefore, relatively insoluble forms of inorganic copper compounds, such as cupric hydroxide, have been found to be more effective fungicides. (Not all water insoluble Cu compounds are fungicidal or bactericidal. It is known that the in vitro fungicidal activity is largely dependent on its solubility in the spore exudate and in the fungal cell.) The problem with popular copper fiingicides is that, because they are largely water insoluble, they are normally applied in relatively large volume aqueous suspensions and, as such, are readily removed by rain. Frequent applications are thus necessary at short intervals ~ an application process which is expensive and environmentally imprudent. 2 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 WO 98/58546 PCT/US98/12264 Therefore, the need exists for a highly water soluble Cu compound based fungicide and bactericide that avoids the problems associated with phytotoxicity experienced in the past with such compounds. A need also exists for such a water soluble Cu compound based fungicide and bactericides that reduces the adverse Cu load on the plant, thus reducing the non target impact to the environment. Further, a need exists for such fungicidal and bactericidal compounds that permits use of other heavy metals such as manganese, zinc, iron, copper and mixtures thereof, as may be desired to for specific fungicidal or bactericidal properties.

SUMMARY OF THE INVENTION The present invention address the problems outlined above, and provides an improved anti-fungal and anti-bacterial compositions for plants that contains, as active ingredients, fungicidally and bactencidally effective amounts of heavy metal chelates in aqueous solution. According to the present invention, it has been discovered that the application to the plant of the inventive composition substantially eliminates fungus and bacteria disease, while at the same time, is substantially non-phytotoxic Thus, an object of the present invention is to provide a fungicidal composition for protection of plants against a fungal infection.

Another object of the invention is to provide such an antifungal protection with a single product that upon application is not excessively phytotoxic.

Another object of the invention is to provide a method for treating plants and to provide anti-fungal protection for plants against attack by fungus. Yet, further 3 Printed from Mimosa 1 2 3 4 6 7 8 #, 11 12 13 14 16 #n 18 19 21 i object of the invention is to provide an anti-fungal composition for treating plants that is environmentally safe, inexpensive to use and has low mammalian toxicity.

Thus, an object of the present invention is to provide a bactericide composition for protection of plants against a bacterial infection.

Another object of the invention is to provide a composition employing heavy metal chelates that functions as both a fungicide and bactericide.

These and other objects of the invention are obtained by invention disclosed below. It is to be appreciated that the above objects are each to be read disjunctively with the object of to at least provide a useful alternative According to one aspect of the invention, anti-fungal compositions for the protection of plants preferably contain, as an active material, a fungicidally effective amount of a heavy metal chelate in mixture with an agriculturally acceptable carrier such as water. According to another aspect of the invention, anti-bacterial compositions for the protection of plants preferably contain, as an active material, a bactericidally effective amount of a heavy metal chelate in mixture with an agriculturally acceptable carrier, such as water.

According to another aspect of the invention, a single composition having both fungicidal and bactericidal qualities is provided and contains fungicidally and bactericidally effective amounts of heavy metal chelates in mixture with an agriculturally acceptable carrier such as water.

The fungicidal and bactericidal compositions each preferably employ a heavy metal chelate selected from the group consisting of Fe-EDDHA (ethylene-diamine di (O-hydroxy phenylacetate)), Cu-EDDHA, Mn-EDDHA, and Zn-EDDHA and mixtures thereof. t"- uZ ScP LJJ 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 WO 98/58546 PCT/US98/12264 According to another aspect of the invention, the amount of heavy metal chelate is from about 0.01 to about 1.0 pounds AI per acre A DESCRIPTION OF THE DRAWINGS: Fig 1 is the chemical structure for Fe EDTA (iron chelate of ethylene diamine tetraacetic acid).

Fig 2 is the chemical structure for FE DTPA (iron chelate of diethylene-triamine pentaacetic acid).

Fig 3 is the chemical structure for Fe EDDHA (iron chelate of ethylene dihydroxyphenylacetic acid) or as listed in the U.S. Patent 2,921,847 ferrous and ferric-APCA (iron chelates of ethylene bis(alpha imino-ortho-hydroxyphenylacetic Acid)).

Fig 4 is the chemical structure for Fe pEDDHA (iron chelate of para ethylene diamine dihydroxyphenylacetic acid).

Fig 5 is the chemical structure for Fe EDDHMA (iron chelate of ethylene diamine dihydroxyphenylmethylacetic acid).

Fig 6 is the chemical structure for Cu EDDHA (copper chelate of ethylene diamine dihydroxyphenylacetic acid).

A DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The following examples set forth preferred concentrations and techniques for formulation thereof, as well as methods of application and use in test results, demonstrating the efficacy of the inventive concentration in protecting plants against attack by fungi or bacteria, or both. It is to be understood, however, that these Examples are presented by way of illustration only and nothing therein shall be Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 taken as a limitation upon the overall scope of the invention The specific components tested in the Examples were prepared and applied as follows: Cu-EDDHA was and can be prepared using the process disclosed in U.S.

Patent 2,921,847, the teachings of which are hereby incorporated herein by reference. The '847 patent describes the process for the preparation of Fe-EDDHA, which in the '847 patent is referred to as ferrous and ferric-APCA (iron chelates of ethylene bis(alpha amino-ortho-hydroxyphenylacetic acid). To prepare Cu-EDDHA, an appropriate Cu salt need merely be substituted for the iron salts disclosed in the '847 patent. Likewise, other heavy metal chelates disclosed herein may be prepared by substituting the desired heavy metal for Cu in the process disclosed in the '847 patent. The chemical structure for Cu-EDDHA is illistrated in Fig. 6. The chemical structures for other common heavy metal chelates are illistrated in the following figures: Fig. 1 Fe-EDTA; Fig. 2, Fe-DTPA; Fig. 3, Fe-EDDHA; Fig. 4, Fe-pEDDHA; and Fig 5, Fe-EDDHMA.

Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising" and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, m the sense of "including, but not limited to".

METHOD OF APPLICATION The preferable method of application is foliar, either by ground or aerial equipment, but is not limited to that method alone Injection or soil applications, for example, can also be applications depending upon specific crops and pathogens.

The inventive compositions have utility on fruit crops, and agronomic crops, ornamentals, trees, grasses, vegetables, grains, and flori cultural crops, as well as, some aquatic crops including rice. 6 Or i. / 1 1 C'r ? 1 1 J W_J 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 The fungicidal and bactericidal properties of the compounds according to the invention are various, but are particularly interesting in the case described in the following examples: As used in the Examples, "Ave. % infection" means percent of leaves that exhibit fungus lesions.

EXAMPLE 1 Cu-EDDHA and four commercially accepted fungicidal compositions were applied to Valencia orange on sour orange rootstock Applications were in 100 gallons of solution (in the concentrations indicated) per acre in mid-summer to single-tree plots replicated six times in a randomized complete block ("RCB") design. Seven months later the percentages of citrus greasy spot infection on five branch terminals from each tree were recorded and averaged.

CITRUS GREASY SPOT TEST CAUKINS GROVES, INDIANTOWN, FLORIDA TREATMENT RATE/100 * AVE % GAL. INFECTION 2/10/88 1) FCC-455 Spray Oil (Fla. Citrus Commission) 2) Difenconazole 3) Difenconazole 4) Cu-EDDHA 3.2% ) KOCIDE 101 6) Untreated 50 g ai 100 g ai 0.2 lb ai 4 lbs. 1% 0 1.56 1.0 2.5 23 35 APPL. Single tree plots x 6 Reps.

* Aug. 5 terminals/tree 7 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 22 23 Difenconazole: l-[2-[4-(4-chlorophenoxy)-2-chlorophenyl-(4-methyl-l, 3-dioxolan-2-yl)-methyl]]-lH-l,2,4-triazole (available from Ciba-Geigy, Greenbough, N.C.) Cu-EDDHA: sodium cupric ethylene-diamine di (o-hydroxyphenylacetate).

KOCIDE 101 available from Griffin Corp., Valdosta, Ga * % infection of citrus greasy spot (Mvcosphaerella citril EXAMPLE 2 FUNGICIDE Cu-EDDHA, TILT (propiconzaole-Ciba-Geigy) and difenconozole were applied in 100 gpa to single tree plots of "Valencia" oranges replicated five times in a RCB design m mid-July.

Twenty mature leaves (from the spring flush) per replicate were harvested approximately 4 months later and placed under greenhouse conditions and alternately wetted and dried to simulate natural defoliation and weathering.

These conditions m turn cause the fungus to sporulate by the formation of perithecia (spore production body of fungus) which were counted as a means of measuring the fungicidal activity of the treatments. These data are presented below.

CITRUS GREASY SPOT SCN NURSERY, DUNDEE, FLORIDA RATE/100 TREATMENT GAL.

^PERITHECIA 1) Cu-EDDHA 3.2% 0.2 lb ai 3.24 b 2) Cu-EDDHA 3.2% 0.4 lb ai .93 ab 3) TILT 3 6 EC 6 oz. Prod. 6.62 ab 4) Difenconzaole 100 g ai .32 ab ) Difenconazole 200 g ai 11.57 ab 6) CONTROL inoculated 7.97 ab 7) CONTROL not inoculated 6.42 ab 8 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 WO 98/58546 PCT/US98/12264 Function: ANOVA—1 Date case no. 1 to 42 Without selection One way ANOVA grouped over variable 1 TREATMENT NUMBER with values from 1 to 7 Variable 3 NUMBER OF PERITHECIA PER 5MM FIELD AT 2.5 X -MEAN OF THREE OBSERVATIONS ANALYSIS OF VARIANCE TABLE Degrees of Sum of Error Mean Freedom Squares Square F-value Prob.

Between 6 226.6508 37.78 1.33 .270 Within 34 965.0170 28.38 Total 40 1191.6678 EXAMPLE 3 FUNGICIDE Cu-EDDHA, Kocide (cupric hydroxide) and difenconazole were applied to single tree plots of "Hamlin" oranges in 100 gpa (in concentration indicated) in a RCB design replicated 4 times. Applications were made in May, June and May and June. Ten fruit/replicate were sampled in July and percent infection of Melanose (Diaporthe citri) was determined. See data presented below. 9 Printed from Mimosa 1 CITRUS MELANOSE CONTROL 2 R.E. KEENE FRUIT COMPANY RATE LBAI/100 % INFECTION 3 TREATMENT GAL.

TIMING (FRUIT) 4 Cu-EDDHA 3.2% 0.2 May 9 Cu-EDDHA 3.2% 0.4 May 13 6 Cu-EDDHA 3.2% 0.8 May 21 7 Cu-EDDHA 3.2% 0.2 May-June 11 8 Cu-EDDHA 3.2% 0.4 May-June 9 Cu-EDDHA 3.2% 0.8 May-June 29 Cu-EDDHA 3.2% 02 June 14 11 KOCIDE 4.0 May 12 12 KOCIDE 0.4 May-June 13 DIFENCONAZOLE 0.5 June 4 14 Untreated 38 4 REPS SINGLE TREE PLOTS. 16 PENETRATOR (surfactant - non-iomc)@ 4 oz. ALL TREATMENTS 17 EXAMPLE 4 FUNGICIDE 18 GRAPEFRUIT (Citrus paradisi 'Marsh') 19 Greasy spot; Mvcosphaerella citn GREASY SPOT CONTROL ON LEAVES, 1986-87: Spray treatments 21 were applied dilute (applied to point of run off) by handgun in July to 10-ft-high 22 trees at a rate equivalent to 700 gal/acre Treatments were replicated on 8 single- 23 tree plots in a RCB design. Groups of 15 shoots on each of the east/west and east 24 side of each tree were tagged and the initial number of leaves was recorded. In February, remaining leaves were counted and examined for greasy spot.

Printed from Mimosa 1 All treatments except Difolatan (fungicide) reduced greasy spot-induced 2 defoliation and the percentage number of remaining leaves with greasy spot 3 symptoms. There were no significant differences in effectiveness between Tribasic 4 copper sulfate, spray oil, Spotless, Tilt, and Cu-EDDHA There was too little greasy spot rind blotch in this test to provide information on the relative efficacy of 6 treatments for preventing fruit infection. % remaining leaves 7 Treatment and rate/100 gal defoliation with greasy spot 8 Tribasic copper sulfate (53% Cu) 0.75 lb 1.9 a .1 a 9 Sunspray 7E oil 1 gal 3 1a 27 0 a Difolatan 80 Sprills 1.25 lb 8.9 b 49.8 b 11 Spotless 25W 0.8 lb 1.3 a 22.6 a 12 Tilt 3.6EC 8 fl oz 1.5 a .9 a 13 Cu-EDDHA (3.2% Cu) 1.5 gal 08 a 12.0 a 14 Untreated 9.7 b 48.5 b EXAMPLE 5 FUNGICIDE 16 Cu-EDDHA, TILT (propinconazole), difenconozole and MERTECT (Merck 17 Chem., N J ) (thiabendazole) were applied in 100 gpa to 2-year-old laurel oaks 18 (Quercus hemispherica) in 2x2 gal. pots in a RCB design replicated 4 times. 19 Applications were made in July approximately 3 weeks apart and rated in August a month later. See data below. 21 11 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 OAK LEAF BLISTER (Taphrina caerulescens) CONTROL TRAILRIDGE NURSERY, KEYSTONE HEIGHTS, FLORIDA 1) Tilt 3.6 emulsifiable 2) Difenconazole 3.6 TREATMENT RATE/PROD 100 GAL. 8 oz 2 oz ^DISEASE INDEX 1.5 2.25 emulsifiable 3) Cu-EDDHA 3.2 4) MERTECT ) Untreated 8 oz 8 oz 2.8 1.5 4.25 * Disease Index: Rated 8/26/86. 1 = no disease 2 = light 3 = moderate 4 = heavy = dead foliage 2 x 2 gal trees/exp. unit x 4 Reps in a RCB design EXAMPLE 6 BACTERICIDE Cu-EDDHA and Kocide (cupric hydroxide) were applied as foliar spray in May to Hibiscus sinensis cuttings (100/replicate) x 4 replicates in a RCB design. Treatments were allowed to dry for one hour and then placed in a commercial propagation bed under intermittent mist and rated for bacterial (Erwinia chrysanthemi) infection one week later. Data presented below. 12 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 *ERWINIA CONTROL ON HIBISCUS NELSONS NURSERY, APOPKA, FLORIDA RATE/CU AVG. % TREATMENT 100 GAL. INFECTION 1) Cu-EDDHA 3.2% 0.2 lb. ai 6 2) Cu-EDDHA 3.2% 0.4 lb. ai 8 3) KOCIDE 101 2 lbs. ai 25 4) Untreated — 100 100 Cuttings/REP X 4 *ERWINIA chrysanthemi EXAMPLE 7 BACTERICIDE A follow-up experiment to EXAMPLE 6 was conducted on rooted cuttings which were dipped as they were removed from the propagation bed and foliarly sprayed 7 days later after being potted. Cu-EDDHA and Kocide were applied at the rates specified below in a RCB design utilizing 100 plants/replicate x 4 reps. Potted cuttings had not received any previous bactericide treatments prior to potting.

ERWINIA CONTROL ON HIBISCUS NELSONS NURSERY—APOPKA, FLORIDA RATE/LBAI AVE. % TREATMENT 100 GAL. INFECTION Cu-EDDHA 3 2% 0.2 19 Cu-EDDHA 3.2% 0.8 32 KOCIDE 2.0 22 APPLIC. DATES: 7/19 DIP, 7/26/85 SPRAY 100 PLANTS/REP. X 4 EXAMPLE 8 BACTERICIDE Control of Bacterial Spot on Pepper Plants With Stage II Bactericides 13 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 WO 98/58546 PCT/US98/12264 Procedure—Earlv Cal Wonder variety pepper plants were treated at weekly intervals with the following bactericides (g ai/liter): copper + mancozeb (2 + 1), Cu-EDDHA (0.1), CGA (Ciba-Giegy of America ~ Bactericides)-115944, CGA-151731, CGA-157566, and CGA-164058 (each at 0.25 and 0.5), CGA-143268 (1.0). Treatments were applied weekly in 1000 1/ha for a total of eight applications. The crop was artificially inoculated after the first and third applications. Disease severity was evaluated after the fourth and eight applications. Phytotoxicity was rated after the eight application and yields were taken continually during the test.

Results—Disease pressure was moderate and uniform. After four applications, the best treatments were CGA-115944, CGA-151731, and CGA-164058. CGA-157566 was less effective than the three previously mentioned compounds but more effective than CGA-143268 which was equal to copper plus mancozeb and Cu-EDDHA in activity The ranking of compounds changed when treatments were rated 12 days after the last application Copper plus mancozeb control has completely broken down, which was expected because disease conditions were severe in the final half of the test and copper should be applied on a five-day schedule under these conditions. Cu-EDDHA at only 0 05X the rate of Kocide 101 (on a metallic copper basis) was exhibiting some control and was equal to CGA-143268, CGA-157566, and CGA-164058. The best bactericide at the second rating were CGA-115944 and CGA-151731. The phytotoxicity of all treatments was assessed after eight applications had been made. The only bactericides which were phytotoxic were CGA-115944 and CGA-164058 CGA-164058 was safer than 14 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 CGA115944 which was marginally unacceptable at 0.5 g ai/1. CGA-143268 and CGA-164058 increased yields dramatically Yields were depressed by CGA-0115944, CGA-151731, and CGA-157566. Cu-EDDHA had no effect on yield and copper + mancozeb increased yields moderately. In summary, several compounds showed excellent activity, but none had sufficient crop safety.

EXAMPLE 9 BACTERICIDE Cu-EDDHA at 0.2 and 0.4 lbs. ai/100 gal. and Kocide 101 at 7.4 lbs. ai/A were applied as foliar applications to croton (Codiaeum variegatum) previously inoculated with Xanthomonas campestris a day earlier Treatments were assigned in a RCB design and replicated 10 times with single pots Treatments were applied 3 times on a weekly schedule and evaluated at 7 and 14 days following the last application. See data below Test 1 Codiaeum Inoculated with Xanthomonas Number of leaves with symptoms TREATMENT Water Water Cu-EDDHA 3.2% Cu-EDDHA 3 2% Kocide 101 RATE/100 GAL. a.i. noninoculated inoculated 26 ml (.2 lb.) 52 ml (.4 lb.) 6.8 ml. (7 4 lb.

AVE. % INFECTION 0 a 2.6 c .6 ab 1.0 b .9 ab ANOVA table Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 Source Treatment Error Total Sum of squares df 37.28 4 45.7 45 82.98 49 Mean square F Value 9.319 9.177 significant at 1 % level 1.016 All of the copper treatments provided some control of Xanthomonas leaf spot of Codiaeum, when compared to the inoculated control. The lower rate of Cu-EDDHA and the Kocide 101 gave control equal to the noninoculated control treatment.

CARROT/ALTERNARIA FUNGICIDE TRIAL AVG % INFECTION RATE/100 TREATMENT GAL. 04/05/96 04/23/96 1) K-PHOS 1% 69 8.2 2) PHOS-MIGHT 1% 18 7 28.8 3) K-PHOS 0.5% 8.9 .7 + + PHOS-MIGHT 0 5% 4) Cu-EDDHA 0.2 lb ai 8.8 11.6 ) Fe-EDDHA 0.2 lb ai 12 7 12.9 6) Untreated — 23 0 34.8 *EDDHA (ethylene-diamine di (O-hydroxy phenylacetate) PLOT SIZE: Single Row X ft. X 4 reps in a RCB design.

Application dates: 2/2, 9,15,22,3/8,14,22, and 28. Rated 4/5 and 4/23/96 NOTE: Second rating was 25 days after last fungicide application. Plots were inoculated with Alternaria dauci Sanford, FL K-PHOS (Commercially available and is sold under trademark "K-Phos" by Foliar Nutrients, Inc., Cairo, GA 31724) (lyHPO*, 0-18-20) 16 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 22 23 WO 98/58546 PCT/US98/12264 PHOS MIGHT (Commercially available and is sold under trademark "Phos Might" by Foliar Nutrients, Inc., Cairo, GA 31724) (K2HP03, 0-22-20) EXAMPLE 15 - FUNGICIDE CRAPE MYRTLE POWDERY MILDEW CONTROL AVG % INFECTION TREATMENT RATE/100GAL. FL GL FOLIAGE 1) K-PHOS 1% 12.0 22.50 2) Cu-EDDHA 0.2 lb ai 11.20 16.4 3) Fe-EDDHA 0.2 lb ai 6.4 0 4) K-PHOS 1% 4.2 0 + Cu-EDDHA 0.2 lb ai 100 100 FL.GL =unopended flower clusters (2/trtm X 4 reps) Foliage (2 terminals - 10 leaves X 4 reps in RCB design) Crape Myrtle (Lagerstromia indica) Powdery Mildrew (Erysiphe lagerstroemiae) App. dates: 5/23, 30th and 6/6. Rated: 6/9 K-PHOS - (K2HP04, 0-18-20) ("K-Phos" is a trademark of Foliar Nutrients, Inc., Cairo, Ga.) The above Examples demonstrate that the inventive compositions are useful in protecting plants against attack by fungus with the application of the inventive solution.

It will be further appreciated that foliar application of the inventive compositions will be effective as a common agricultural practice to control bacterial infections in plants 17 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 WO 98/58546 PCT/US98/12264 As used herein, the term "heavy metal chelate" is intended to refer to an organic coordination "complexmg" compound m which a metal ion is bound to atoms of non-metals, e.g., nitrogen, carbon or oxygen, to form a hetrocylic ring having coordinate covalent bounds. The non-metal atoms may be attached to the metal ions by from one to six linkages and, thus, are called uni-, bi-, tri- dentate, etc., meaning 1-, 2-, or 3-tooth. Heavy metals, such as cobalt, copper, iron, nickel, zinc, magnesium and platinum are metal ions that are commonly involved in chelate structures Examples of heavy metal chelate structures include: Fe-HEEDTA (hydroxy ethylenediamine triacetic acid), Fe-EDTA (ethylenediamine tetra acetic acid), Fe-DTPA (diethylene triaminepenta acetic acid), Fe-EDDHA (ethylene dihydroxyphenylacetic acid), ethylene bis dithiocarbamates of Mn- and Zn-, Cu-EDDHA, Mn- and Zn-EDDHA.

As used herein, unacceptably high levels of phytotoxicity is intended to mean foliar burn, defoliation and stem die-back, or necrosis, plant stunting or death. Phytotoxicity is also rated on an international scale of 0-10 where 0 is equal to no phytotoxicity and 10 is complete death of the plant.

Heavy metal chelates disclosed herein are possess water solubility acceptable for use in the inventive fungicide and bactericide.

For example, the solubility of sequestrene 138 Fe Iron Chelate in pounds per 100 gallons of water, at various temperatures (solubility weight/100 gals. HjO) is shown in Table 1 below: 18 Printed from Mimosa 1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21 Temperature (°C) Lbs. 0 40 69 70 75 81 84 50 88 Commercially produced Sequestrene 138 Fe contains 6% Iron as metallic, or 8.5% iron as FejOj. The commercial product has a moisture content of not more than Without being limited to this theory, it is believed that heavy metal chelation generally increases water solubility of the heavy metal ion and the availability in certain soil conditions of the metal ion where calcareous and high pH situations would otherwise prevent metal ions from being available to the plant as a fungicide.

It is believed that certain heavy chelates (usually in the form of Mn, Zn, and Fe) may be applied foriarly at much reduced rates when compared to inorganic salts intended for fungicidal and bactericidal use.

Ranking of Fe chelates used in foliar applications are as follows. Fe-HEEDTA -- most phytotoxic; Fe-EDTA - intermediate phytotoxic, Fe-DTPA - less phytotoxic, and Fe-EDDHA - least phytotoxic. Such rankings do not necessarily apply when the chelate is EBDC fungicides in the Mn, Zn form.

It will be appreciated by those skilled in the art that beneficial effects demonstrated in the Examples by the use of Cu-EDDHA will also be obtained when %. 19 Printed from Mimosa WO 98/58546 PCT/US98/12264 1 the Mn, Zn and Fe forms EDDHA and other forms of heavy metal chelates are 2 employed.

Printed from Mimosa

Claims (12)

What is claimed is:

1. A composition for preventing infection by fungal and bacterial pathogens in plants comprising, a heavy metal chelate m aqueous solution, with said heavy metal chelate comprised of a chelate constituent that is an EDDHA compound and a heavy metal, with said heavy metal chelate added to said aqueous solution in an amount equal to between about 0.01 and about 2.0 pounds per AI per acre.

2. The composition of Claim 1 wherein said heavy metal chelate is present in said aqueous solution in amount equal to from about 0.01 to about 0.05 pounds per AI per acre.

3 The composition of Claim 1 or Claim 2 wherein said composition has a phytotoxicity rating of 5 or less.

4. The composition of any one of Claims 1 to 3 wherein said heavy metal chelate has a solubility equal to about 100% where at least 80 pounds of said heavy metal chelate are dissolved m 100 gallons of water at 500 C.

5. The composition of any one of Claims 1 to 4 wherein said heavy metal chelate is added in an amount of equal to between 1% and 5% by weight of the aqueous solution.

6 The composition of any one of Claims 1 to 5 wherein said heavy metal constituent is selected from the group consisting of iron, zinc, tin, manganese, copper, and combinations thereof.

7 The composition of any one of Claims 1 to 6 wherein said heavy metal chelate is selected from the group consisting of Cu-EDDHA, Cu-pEDDHA, Cu-EDDHMA, and combinations thereof. 21 ' r r ^ M * - '

8. The composition of any one of Claims 1 to 7 wherein said chelate constituent is selected from the group consistmg of pEDDHA, EDDHA, and EDDHMA.

9. A fungicide for controlling fungal diseases in plants comprising: a heavy metal chelate in aqueous solution, with said chelate bemg an EDDHA family member, with said heavy metal chelate added to said aqueous solution in an amount equal to between about 0.01 and about 2 0 pounds per AI per acre.

10 The fungicide of Claim 9, wherem the heavy metal is selected from the group consisting of manganese, zinc, iron, tin, copper, and combmations thereof.

11. A method for controlling fungicidal and bacterial disease wherein said method comprises applying to a plant an amount of a heavy metal chelate solution, with said solution added in an amount equal to between 0 01 and 2 0 pounds per AI per acre.

12. A fungicidal and bactericidal composition added to a plant in an amount equal to between about 0 01 and about 2.0 pounds per AI per acre, with said composition selected from the group consisting of Cu-EDDHA, Cu-pEDDHA, Cu-EDDHMA, and combinations thereof. 13 A composition as claimed m claim 1 substantially as herein described with reference to any one of the Examples. 14 A method of controlling fungicidal and bacterial disease as claimed in claim 11 substantially as herein described with reference to any one of the Examples. END OF CLAIMS