Biological fungicide composed by plant extracts

Abstract

The invention describes a natural fungicide which comprises gallnut and myrobalan extracts which exhibit a synergistic effect against Alternaria brassicicola, and can be used to control crop fungal diseases.

Claims

1. A method for applying a fungicide to an agriculture crop comprising applying a fungicide effective amount of: (A) 20-60 wt % Gallnut extract; and, (B) 80-40 wt % Myrobalan extract; the combination of (A) and (B) is a more effective fungicide than if either (A) or (B) are used alone.

2. The method of claim 1 where the fungicide composition further includes a surfactant.

3. The method of claim 2 wherein the surfactant is selected from the group consisting of: sodium lauryl sulfate and yucca extract.

4. A fungicide consisting essentially of: between about 20-60 wt % aqueous Gallnut extract; between about 80-40 wt % aqueous Myrobalan extract; and, about 5 wt % sodium lauryl sulfate.

Description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(1) The method used to create formulations according to the invention will be discussed followed by the treatment results.

(2) The active ingredients of both gallnut and myrobalan are extracted from their respective powder form. The preferred method is to mix pre-determined amounts of gallnut and myrobalan in a pre-determined amount of solvent and heat for a pre-determined period of time to release the active ingredients into solution, and then remove the dross by filtration.

(3) In a most preferred embodiment, the filtrate is heated to evaporate additional liquid to form a concentrated natural fungicide into which surfactant can be optionally added. Examples of surfactant include yucca extract in a range of between 0% and 15% by volume or SLS in a range of between 0% and 10% by weight.

(4) In order to approximate the amount of active ingredients of gallnut and myrobalan present in the filtrate, testing was performed.

(5) 200 grams horned gallnut (i.e. powder form) was combined with 1000 ml water and heated for 60 minutes at 100° C. Thereafter, the solution was filtered. The dross was dried and weighed 159.4 grams from which gallnut extract is determined to weigh 40.6 grams. The ratio of overall weight of gallnut to the weight of gallnut extract is 4.93:1 (200÷40.6).

(6) 200 grams myrobalan (i.e. powder form) was combined with 1000 ml water and heated for 60 minutes at 100° C. Thereafter, the solution was filtered. The dross was dried and weighed 173.2 grams from which myrobalan extract is determined to weigh 26.8 grams. The ratio of overall weight of myrobalan to the weight of myrobalan extract is 7.46:1 (200÷26.8).

(7) Numerous solvents, besides water could be used for extraction including: a) 50% to 75% alcohol; b) 60% to 75% acetone; or, c) 50% alcohol and 50% acetic acid whereby the extraction process would preferably be performed at ambient conditions.

(8) The following describes the procedure for making the formulation described below in Row 6 of Table 1-1 for 20% (vol) Gallnut and 30% (vol) Myrobalan.

(9) a. add 400 grams gallnut powder and 600 grams myrobalan powder to 5000 ml water (i.e. 1000 grams powder to 5000 ml solvent) to form a solution.

(10) b. heat the solution for between 30-60 minutes at 100° C. and add water as necessary to maintain a constant solution volume (i.e. 5000 ml).

(11) c. thereafter, filter the solution thru a 44 μm mesh to remove undissolved solids dross from the filtrate.

(12) d. heat filtrate to reduce volume to a pre-determined volume (i.e. 1000 ml) thus forming a concentrated solution.

(13) 50 ml of the concentrated solution is combined with 50 ml water to become the concentrated natural fungicide described in Row 6 of Table 1-1. As shown in Table 1-1, the formulation can be diluted up to 1000 times and used as an effective use-dilution fungicide to control crop fungal disease caused by Alternaria brassicicola.

(14) Alternatively, the heating procedure described in step b above could also occur under pressure. As an example, the solution could be heated for a shorter period of time, 121° C. for 15-45 minutes under 15 PSIG.

(15) The following are examples of the synergistic effect of the formulation when diluted and used for anti-fungal purposes:

Inhibitory Effect of Plant Extract Formulation on Conidial Germination of Alternaria brassicicola

(16) Varied formulations were made and tested. Neither gallnut or myrobalan possess inhibitory effects when used individually in the specified concentrations. However, when a formulation comprises gallnut and myrobalan in the concentrations specified, the formulation has a synergistic effect with regard to treatment of the plant fungal pathogen Alternaria brassicicola.

(17) Tables 1-1 and 1-2 show the conidial germination rates of Alternaria brassicicola. The tables differ only in how the gallnut and myrobalan are presented. For Table 1-1, gallnut and myrobalan are presented in vol % as described earlier for the Row 6 procedure while Table 1-2 presents the active ingredients of gallnut and myrobalan as concentration (grams/ml).

(18) One drop of 20 μl of pathogen conidia suspension (100 conidia per microliter) was mixed with one drop of 20 μl for each of the eight combinations of gallnut and myrobalan formulations, and at dilutions of 750 times, 1000 times, and 1500 times. Each combination was placed on test slides that were maintained at 100% relative humidity at room temperature. The germination rate of 100 conidia on each slide was calculated visually using a microscope following an incubation period of 24 hours.

(19) The conidial germination rates of Alternaria brassicicola in water alone were between 96-98%. The germination of Alternaria brassicicola conidia decreased from 98% to 42% when 20% gallnut was diluted with 750 times water but only decreased to 94% when 15% gallnut was diluted with 750 times water. The germinations of Alternaria brassicicola conidia was only reduced from 98% to 95% when 30% myrobalan was diluted with 750 times water while there was no change when 20% myrobalan was diluted with 750 times water.

(20) It can be concluded that when 20% gallnut was diluted with 750 times water, it caused a partially inhibitory effect on Alternaria brassicicola conidial germination. However, 30% or 20% myrobalan diluted with 750 times water showed no inhibition on conidial germination of Alternaria brassicicola.

(21) In contrast to single applications of either gallnut or myrobalan, a synergistic effect was observed when gallnut and myrobalan were combined at various ratios between 15-20% by volume gallnut to 20-30% by volume myrobalan. The germination rates were completely suppressed at 750 times and 1000 times dilution and a noticeable rate reduction was observed even at 1500 times dilution.

(22) The most effective combinations observed were: (1) concentrated gallnut extract in 20% and concentrated myrobalan extract in 30%; (2) concentrated gallnut extract in 20% and concentrated myrobalan extract in 20%; and, (3) concentrated gallnut extract in 15%, and concentrated myrobalan extract in 30%. The conidial germination of Alternaria brassicicola could not be completely inhibited when the three formulations were diluted to 1500 times.

(23) Based on the test results described above and in the following tables, a natural fungicide as described herein can be applied to an agriculture crop at a rate from about 2.0-8.5 oz./20-100 gal. of water per acre and wherein the fungicide composition comprises: (A) the active ingredients from about 15 wt. % to 80 wt. % gallnut; and, (B) the active ingredients from about 85 wt. % to 20 wt. % myrobalan;
the combination of (A) and (B) is a more effective fungicide than if an equivalent amount of either (A) or (B) are used alone.

(24) TABLE-US-00001 TABLE 1-1 Inhibition effect of single plant extracts and their combinations under dilution to 750, 1000 and 1500 times on Alternaria brassicicola conidial germination* Conidial germination rate (%) in Vol %** different diluted condition Gallnut Myrobalan Water 750× 1000× 1500× 0 0 100 98 96 96 20 0 80 42 97 94 15 0 85 94 98 97 0 30 70 95 96 97 0 20 80 98 96 95 20 30 50 0 0 71 20 20 60 0 0 77 15 30 55 0 0 59 *The conidial germinations of Alternaria brassicicola were tested on slides in a moist chamber. Four replicates for each treatment, and germination rate were calculated in each germination rate. The conidial germination rates were observed in 24.sup.th hours after the treatment. **An equal weight (in grams) of gallnut and myrobalan powder to an equal volume (in ml) were used.

(25) TABLE-US-00002 TABLE 1-2 Inhibition effect of single plant extracts and their combinations under dilution to 750, 1000 and 1500 times on Alternaria brassicicola conidial germination* Single plant extract and ratio of combination** Conidial Gallnut Myrobalan germination rate (%) in Extract Extract Formulation different diluted condition (gms) (gms) volume (ml) 750× 1000× 1500× 0 0 100 98 96 96 4.06 0 100 42 97 94 3.04 0 100 94 98 97 0 4.02 100 95 96 97 0 2.68 100 98 96 95 4.06 4.02 100 0 0 71 4.06 2.68 100 0 0 77 3.04 4.02 100 0 0 59 *The conidial germinations of Alternaria brassicicola were tested on slides in a moist chamber. Four replicates for each treatment, and germination rate were calculated in each germination rate. The conidial germination rates were observed in 24.sup.th hours after the treatment. **Dry weights were calculated as follows: 1 gram gallnut extract requires 4.93 grams gallnut; 1 gram myrobalan extract requires 7.46 grams myrobalan.

Inhibitory Effect of Plant Extract Compound Formulation with Surfactants on Conidial Germination of Alternaria brassicicola

(26) Tables 2-1 and 2-2 show the same plant extract formulations as in Table 1 but including the addition of a surfactant; specifically, either yucca plant extract (Yucca schidigera) or sodium lauryl sulfate (SLS). Each was added for testing conidial germinations of Alternaria brassicicola. The formulations were diluted to a higher degree than as presented in Tables 1-1 and 1-2. Dilutions were at 1000 times, 1500 times and 2000 times water.

(27) 10 vol % of yucca extract or 5 wt. % of SLS was added to the formulations and then used to test the inhibitory effects on conidial germination on the same fungal pathogen Alternaria brassicicola.

(28) The results indicated that the addition of 10 vol % of yucca extract provided complete conidial germination inhibition to all combinations of gallnut and myrobalan extracts up to 1000 times water. However, yucca extract at 1500 times or higher was not as effective as when not used.

(29) The results indicated that the addition of 5 wt. % SLS provided complete conidial germination inhibition to all combinations of gallnut and myrobalan extracts up to 1500 times water. The results showed when added the SLS in the formulas, the complete inhibition of conidial germination of Alternaria brassicicola can be improving from 1000 to 1500 times.

(30) TABLE-US-00003 TABLE 2-1 Inhibition effect of plant extracts combinations adding with natural surfactant or chemical surfactant on conidial germination of Alternaria brassicicola* Percentage of each Conidial ingredients %** germination rate (%) in Gall- Myrob- Yucca different diluted condition nut alan*** Extract SLS Water 1000× 1500× 2000× 0 0 0 0 100 95 96 94 20 30 10 0 40 0 95 94 20 20 10 0 50 0 94 95 15 30 10 0 45 0 98 97 0 0 10 0 90 53 94 95 20 30 0 5 45 0 0 91 20 20 0 5 55 0 0 92 15 30 0 5 50 0 0 88 0 0 0 5 95 55 90 94 *The conidial germinations of Alternaria brassicicola were tested on slides in a moist chamber. Four replicates for each treatment, and germination rate were calculated in each germination rate. The conidial germination rates were observed in 24 hours after the treatment. **Except SLS is measured by weight % (grams), the other ingredients are measured by volume % (ml). ***An equal weight (in grams) of gallnut and myrobalan powder to an equal volume (in ml) were used.

(31) TABLE-US-00004 TABLE 2-2 Inhibition effect of plant extracts combinations adding with natural surfactant or chemical surfactant on conidial germination of Alternaria brassicicola* Ratio of plant extracts with surfactants combination Conidial Gallnut Myrobalan Yucca germination rate (%) in Extract Extract Extract SLS Formulation different diluted condition (gms) (gms)** (ml) (gms) volume (ml) 1000× 1500× 2000× 0 0 0 0 100 95 96 94 4.06 4.02 10 0 100 0 95 94 4.06 2.68 10 0 100 0 94 95 3.04 4.02 10 0 100 0 98 97 0 0 10 0 100 53 94 95 4.06 4.02 0 5 100 0 0 91 4.06 2.68 0 5 100 0 0 92 3.04 4.02 0 5 100 0 0 88 0 0 0 5 100 55 90 94 *The conidial germinations of Alternaria brassicicola were tested on slides in a moist chamber. Four replicates for each treatment, and germination rate were calculated in each germination rate. The conidial germination rates were observed in 24.sup.th hours after the treatment. **Dry weights were calculated as follows: 1 gm gallnut extract requires 4.93 grams gallnut; 1 gram myrobalan extract requires 7.46 grams myrobalan.

(32) From the results of the foregoing tables, a combination of gallnut extract and myrobalan extract has a synergistic effect on the ability to inhibit crop fungal diseases caused by phyto-pathogenic fungi, namely Alternaria brassicicola than if gallnut extract or myrobalan extract were used separately.

(33) As used herein, the term “about”, when referring to a value or to an amount of mass, weight, time, volume, concentration, or percentage can encompass variations of, in some embodiments ±20%, in some embodiments ±10%, in some embodiments ±5%, from the specified amount, as such variations are appropriate in the disclosed application.

(34) It is understood that, in light of a reading of the foregoing description, those with ordinary skill in the art will be able to make changes and modifications to the present invention without departing from the spirit or scope of the invention, as defined herein. For example, those skilled in the art may substitute materials supplied by different manufacturers than specified herein without altering the scope of the present invention.