Method of improving turfgrass abiotic stress tolerance

Abstract

The present invention relates to a method of controlling abiotic stress on turfgrass using an effective non-phytotoxic amount of acibenzolar-s-methyl.

Claims

1. A method for controlling or suppressing abiotic stress in cool-season turfgrass, comprising applying to the cool-season turfgrass or to the locus of the cool-season turfgrass, a turf quality improving non-phytotoxic amount of acibenzolar-S-methyl applied at a rate of from 4 to 20 g/ha and a turf quality improving non-phototoxic amount of chlorothalonil applied at a rate of from 2,000 g/ha to 10,000 g/ha, and wherein the method provides improved control or suppression of abiotic stress in cool-season turfgrass over application of either acibenzolar-S-methyl or chlorothalonil alone.

2. The method of claim 1, wherein the acibenzolar-S-methyl is applied pre-abiotic stress or under low to moderate abiotic stress conditions.

3. The method of claim 1, wherein chlorothalonil and acibenzolar-S-methyl are applied simultaneously together, separately, or in succession.

4. The method of claim 1, applying a composition comprising acibenzolar-S-methyl and chlorothalonil.

5. The method of claim 4, wherein the composition further comprises adjuvants, solvents, carrier, surfactants or extenders.

6. The method according to claim 4, wherein the composition comprises from 0.01 to 90% by weight of the acibenzolar-S-methyl, from 10 to 99.99% of the carrier and from 0 to 20% of the surfactant.

7. The method of claim 1, wherein acibenzolar-S-methyl is applied at the rate of from 5 to 16 g/ha.

8. The method of claim 1, wherein acibenzolar-S-methyl is applied at intervals of from 5 to 21 days, either pre-abiotic stress or under low to moderate abiotic stress conditions, during turf growing season.

9. The method of claim 8, wherein 6 to 8 applications of acibenzolar-S-methyl is applied at intervals of from 7 to 14 days.

10. The method according to claim 1, wherein the turfgrass is an annual or perennial Gramineae belonging to at least one of the genera Agropyron, Agrostis, Axonopus, Bromus, Buchloë, Cynodon, Eremochloa, Festuca, Lolium, Paspulum, Pennisetum, Phleum, Poa, Stenotaphrum or Zoysia.

Description

BIOLOGICAL EXAMPLES

(1) Acibenzolar-S-methyl applied in combination with chlorothalonil has provided turfgrass drought tolerance compared to chlorothalonil applied alone and an untreated check.

Example 1

(2) Greenhouse grown creeping bentgrass (Agrostis stolonifera) was treated with Daconil Action (a commercially available chlorothalonil-ASM formulation; Syngenta) and Daconil Weatherstik (a commercially available chlorothalonil formulation; Syngenta) at 3.6 fluid ounces per 1000 square feet of turf. Daconil Action contains 54% chlorothalonil and 0.176% acibenzolar-S-methyl. Daconil Weatherstik contains 54% chlorothalonil. Rates are equivalent to the following:

(3) TABLE-US-00002 Rate-fluid Chlorothalonil acibenzolar-S- Treatment ounces/1000 sq. ft. g ai/ha methyl g ai/ha Daconil Action 3.6 8250 16.5 Daconil Weatherstik 3.6 8250

(4) Two applications were applied on a 7 day interval. Bentgrass plants were maintained in the greenhouse. Watering was stopped and drought stress imposed in Daconil Action and Daconil Weatherstik treatments 3 days after the last application. The untreated check continued to be watered. Turf quality was rated on a 1-9 scale with 9 being equal to the watered check, 6 being acceptable, and 1 being dead.

(5) Quality ratings 13 days after drought stress was imposed are included in Table 1. Turfgrass treated with Daconil Action maintained an acceptable quality rating of 6.2. This was significantly (P=0.05) different from turfgrass treated with Daconil Weatherstik.

(6) TABLE-US-00003 TABLE 1 Quality Rating from Turfgrass Treated with Daconil Action and Daconil Weatherstik 13 Days After Drought Stress Was Imposed in the Greenhouse. Treatment Rate oz/1000 sq. ft. turf Quality Rating* Check (watered)   9.0 a** Daconil Weatherstik 3.6 2.1 c Daconil Action 3.6 6.2b *Rated on a 1-9 scale with 9 being equal to the watered check, 6 being acceptable, and 1 being dead. **Means with same letter not different, LSD (P = 0.05)

(7) These data support the claim of enhanced drought tolerance in turfgrass when acibenzolar-S-methyl is applied in combination with chlorothalonil. Daconil Action is a unique blend of a multiple-site contact fungicide (chlorothalonil) with acibenzolar-S-methyl a systemic compound used for control of disease through induction of host plant resistance. The mode of action of acibenzolar-S-methyl mimics the natural systemic activated resistance (SAR) response found in most plant species. This SAR response does not involve direct activity against the target pathogens but relies on the plants natural defense mechanism. The SAR response activated by acibenzolar-S-methyl allows the plant to defend itself against abiotic stresses such as drought, heat, cold and salinity.

Example 2

(8) Greenhouse grown creeping bentgrass (Agrostis stolonifera) was treated with Daconil Action and Daconil Weatherstik at 3.6 fluid ounces per 1000 square feet of turf. Daconil Action contains 54% chlorothalonil and 0.176% acibenzolar-S-methyl. Daconil Weatherstik contains 54% chlorothalonil. Rates are equivalent to the following:

(9) TABLE-US-00004 Rate-fluid ounces/ Chlorothalonil acibenzolar-S- Treatment 1000 sq. ft. g ai/ha methyl g ai/ha Daconil 3.6 8250 16.5 Action Daconil 3.6 8250 Weatherstik

(10) Two applications were applied on a 7 day interval. Bentgrass plants were maintained in the greenhouse. Watering was stopped and drought stress imposed on the check and plants treated with Daconil Action and Daconil Weatherstik 4 days after the last application. Turf quality was rated on a 1-9 scale with 9 being best, 6 being acceptable, and 1 being dead.

(11) Quality rating taken 4-10 days after drought stress was imposed are included in Table 2. Turfgrass treated with Daconil Action maintained an acceptable quality rating for at least 2 days longer than turf treated with Daconil Weatherstik. This was significantly (P=0.05) from turfgrass treated with Daconil Weatherstik.

(12) TABLE-US-00005 TABLE 2 Quality Rating from Turfgrass Treated with Daconil Action and Daconil Weatherstik 4-10 Days Days After Drought Stress Was Imposed in the Greenhouse. Rate oz/ Days After Drought Stress was Imposed 1000 sq ft 4 5 6 7 8 9 10 Check 8.75 a 8.63 a 6.13 b 5 ab 3.75 b 3 b 2.25 b Daconil 3.6 Weatherstik 8.38 a 8.25 a 6.38 b 5.38 b 4 b 3.5 b 3.13 ab Daconil 3.6 Action 9 a 9 a 7.88 a 7.25 a 6.38 a 5.75 a 5.25 a

(13) These results support the claim of enhanced drought tolerance in turfgrass when acibenzolar-S-methyl is applied in combination with chlorothalonil.

Example 3

(14) Greenhouse grown creeping bentgrass (Agrostis stolonifera) was treated with Daconil Action and Daconil Weatherstik at 2 and 3.6 fluid ounces per 1000 square feet of turf. Daconil Action contains 54% chlorothalonil and 0.176% acibenzolar-S-methyl. Daconil Weatherstik contains 54% chlorothalonil. Rates are equivalent to the following:

(15) TABLE-US-00006 Rate-fluid ounces/ Chlorothalonil acibenzolar-S- Treatment 1000 sq. ft. g ai/ha methyl g ai/ha Daconil Action 2.0 4600 9.2 Daconil Action 3.6 8250 16.5 Daconil Weatherstik 2.0 4600 Daconil Weatherstik 3.6 8250

(16) Three applications were applied on a 14 day interval. Bentgrass plants were maintained in the greenhouse. Watering was stopped and drought stress imposed on the check and plants treated with Daconil Action and Daconil Weatherstik immediately after the last application. Plants were re-watered 15 days after drought stress was imposed. Turf quality was rated on a 1-9 scale with 9 being best, 6 being acceptable, and 1 being dead.

(17) Quality rating 12-15 days after watering was stopped are included in Table 3. Turfgrass treated with both rates of Daconil Action maintained a improvement in turf quality over the untreated check and plants treated with Daconil Weatherstik in ratings taken 15 days after drought stress was imposed in the greenhouse. This significant (P=0.05) improvement continued to be evident after rewatering.

(18) TABLE-US-00007 TABLE 3 Quality Rating from Turfgrass Treated with Daconil Action and Daconil Weatherstik After Drought Stress Was Imposed in the Greenhouse. Rate Turf Quality (1-9 Scale)* oz/ Days After Drought 1000 Stress Was Imposed Treatment sq. ft. 12 13 14 15 3DARW*** Check 6.3 a** 2.8 bc 1.8 bc 1.1c 1.2 c Daconil Action 3.6 7.4 a 6.7 a 5.6 a 5.7 a 6.2 a Daconil Action 2 7.7 a 6.8 a 5.6 a 5 ab 5.7 a Daconil Weather 3.6 6.7 a 4.4 abc 3.3 abc 2 c 2.2 c Stik Daconil Weather 2 6.5 a 3.7 abc 2.1 bc 2.1 c 2.3 c Stik *Rated on a 1-9 scale with 9 being equal to the watered check, 6 being acceptable, and 1 being dead. **Means with same letter not different, LSD (P = 0.05) ***DARW = Days after re-watering

(19) These results support the claim of enhanced drought tolerance in turfgrass when acibenzolar-S-methyl is applied in combination with chlorothalonil.

Example 4

(20) Greenhouse grown creeping bentgrass (Agrostis stolonifera) was treated with Daconil Action at 3.5 fluid ounces per 1000 sq. ft. of turf. Daconil Action contains 54% chlorothalonil and 0.176% acibenzolar-S-methyl. Daconil Action was compared to Actigard 50WP which contains 50% acibenzolar-S-methyl. Rates are equivalent to the following:

(21) TABLE-US-00008 Chlorothalonil acibenzolar-S- Treatment g ai/ha methyl g ai/ha Daconil Action 8250 16.5 Actigard 50WP 30

(22) The purpose of the trial was to compare multiple applications of Daconil Action (16.5 g ai/ha of acibenzolar-S-methyl) with a single application of Actigard (30 g ai/ha acibenzolar-S-methyl). Two applications of Daconil Action were applied on a 7 day interval prior to inducing drought stress. A single application of Actigard was applied at the same time as the second Daconil Action application. Bentgrass plants were maintained in the greenhouse. Watering was stopped and drought stress imposed on the check and plants treated with Daconil Action and Actigard immediately after the second application of Daconil Action and the single Actigard application. Turf quality was rated on a 1-9 scale with 9 being best, 6 being acceptable, and 1 being dead.

(23) Quality rating 11-13 days after watering was stopped are included in Table 4. Turfgrass treated with Daconil Action maintained a significant (P=0.10) improvement in turf quality over the untreated check and plants treated with Actigard in ratings taken 11-13 days after drought stress was imposed.

(24) TABLE-US-00009 TABLE 4 Quality Rating from Turfgrass Treated with Daconil Action and Actigard After Drought Stress Was Imposed in the Greenhouse. Turf Quality (0-9 scale)* Days After Drought Rate Stress was Imposed g Application 11 11 ai/ha Timing (8:00 AM) (4:30 PM) 12 13 Check 6.63 a** 4.25 b 3.62 a 2.38 ab Daconil 8200 2 applications, 7.25 a 6.25 a 5.75 a 3.75 a Action 7 day interval Actigard  30 Single 6.63 a 4.75 ab 3.18 a 2.00 ab application *Rated on a 1-9 scale with 9 being equal to the watered check, 6 being acceptable, and 1 being dead. **Means with same letter not different, LSD (P = 0.10)

(25) These data support the claim that multiple applications of Daconil Action applying 16.5 g ai/ha of acibenzolar-S-methyl are more effective than a single application acibenzolar-S-methyl in reducing drought stress symptoms. These applications are non-phytotoxic to turf.

Example 5

(26) Greenhouse grown creeping Kentucky Bluegrass (Poa pratensis) was treated with Daconil Action and Daconil Weatherstik at 2 and 3.5 fluid ounces per 1000 square feet of turf. Daconil Action contains 54% chlorothalonil and 0.176% acibenzolar-S-methyl. Daconil Weatherstik contains 54% chlorothalonil. Rates are equivalent to the following:

(27) TABLE-US-00010 Rate-fluid Chlorothalonil acibenzolar-S- Treatment ounces/1000 sq. ft. g ai/ha methyl g ai/ha Daconil 2.0 4600 9.2 Action Daconil 3.5 8250 16.5 Action Daconil 2.0 4600 Weatherstik Daconil 3.5 8250 Weatherstik

(28) The purpose of the trial was to compare multiple applications of Daconil Action (16.5 g ai/ha of acibenzolar-S-methyl) to Daconil Weatherstik for reduction in heat stress. Four applications of Daconil Action and Daconil Weatherstik were applied on a 7 day interval prior to inducing heat stress. Kentucky Bluegrass plants were maintained in an incubator. Heat stress imposed on the check and plants treated with Daconil Action and Daconil Weatherstik immediately after the last application. Temperatures were maintained at 35 degrees C. during the day and 30 degrees C. at night. Turf quality was rated on a 1-9 scale with 9 being best, 6 being acceptable, and 1 being dead.

(29) Quality rating 11-13 days after watering was stopped are included in Table 5. Turfgrass treated with Daconil Action maintained a significant (P=0.10) improvement in turf quality over the untreated check and plants treated with Actigard in ratings taken 11-13 days after drought stress was imposed.

(30) TABLE-US-00011 TABLE 5 Quality Rating from Turfgrass Treated with Daconil Action and Daconil Weatherstik After Drought Stress Was Imposed in an incubator. Turf Quality (0-9 scale)* Days After Heat Application Stress was Imposed Timing 7 12 Check 3.25a** 3.00abc Daconil 3.5 4 applications 3.81a 3.75ab Action 7 day interval Daconil 2.0 4 applications 3.75a 3.5ab Action 7 day interval Dacinil 3.5 4 applications 1.75b 2.06cd Weatherstik 7 day interval Daconil 2.0 4 applications 1.68b 1.93cd Weatherstik 7 day interval *Rated on a 1-9 scale with 9 being equal to the watered check, 6 being acceptable, and 1 being dead. **Means with same letter not different, LSD (P = 0.10)

(31) These data support the claim that multiple applications of DaconilAction applying 9.2 and 16.5 g ai/ha of acibenzolar-S-methyl are more effective than Daconil Weatherstik in reducing heat stress symptoms in turf. These applications are non-phytotoxic to turf.

(32) Although the invention has been described with reference to preferred embodiments and examples thereof, the scope of the present invention is not limited only to those described embodiments. As will be apparent to persons skilled in the art, modifications and adaptations to the above-described invention can be made without departing from the spirit and scope of the invention, which is defined and circumscribed by the appended claims. All publications cited herein are hereby incorporated by reference in their entirety for all purposes to the same extent as if each individual publication were specifically and individually indicated to be so incorporated by reference.