Program 2

Program 7

Curative Program 10

Results Penncross Program 2 Program 7 Curative Program 10

Programs 2,7 Spray 5 Spray 2 Spray 4 Spray 3 Spray 6 Spray1

Difference Between Varieties

Program 7 Clearys 3336 Daconil Ultrex Prostar Heritage Fore Banner Maxx

Fungal Isolations Rhizoctonia solani Rhizoctonia zeae

Objectives Determine which Rhizoctonia species are present Determine when they occur Determine if some fungicides are more effective than others for control of the different species

Materials and Methods Samples of Brown Patch taken twice monthly Diseased leaves surface sterilized and plated out on water agar Mycelia transferred to Potato Dextrose Agar Fungi identified after cultures have matured

Typical AG 2,2 IIIB (“mat rush”) culture appearance ~ 3 wk, PDA

Rhizoctonia zeae

Isolates Results 1999 2000

Results 1999

Results 2000

Clearys 3336 Not Effective on Rhizoctonia zeae

Programs 6,7 Daconil Ultrex Clearys 3336 Heritage Clearys 3336

Clearys 3336 Clearys 3336

Rhizoctonia Reported from Turfgrasses Rhizoctonia solani AG 1 1 A - “sasakii” type - primary pathogen of tall fescue 1 B - “web blight” - sometimes from Poa AG 2,2 IIIB - “mat rush” type - cool season grasses “Turf “ - warm season grasses AG 4 - “praticola” - damping-off; unspecialized AG 5 - rare in tall fescue Rhizoctonia zeae Rhizoctonia oryzae Rhizoctonia cerealis CAG 1 or AG-D -yellow patch in the US AG Q - yellow patch in Japan Weakly virulent or avirulent Binucleate species

Rhizoctonia Blight (Brown Patch) of Cool-season Turfgrasses Agrostis, Poa, Festuca, Lolium spp. all affected Favored by warm, humid summertime conditions “Smoke Ring” symptom characteristic on low mowing heights ( especially Agrostis) Leaf lesions initially result from mycelium from sclerotia or colonized host tissue; lesions may consume entire leaves Rhizoctonia solani AG 1, 1A “sasakii” type and Rhizoctonia solani AG 2,2 IIIB “mat rush” type are the most prevalent pathogens

AUDPC = 4025.9

AUDPC =843.5 cd Al Sig + Fore Dac + Al Sig. Banner + Daconil Ult. Dac Ult Banner + Dac Ult Heritage

AUDPC = 673.8 d DacUlt + Al Sig Prostar Al Sig + Fore Heritage +

AUDPC = 722.8 d Sentinel + Daconil Ult. Daconil Ultrex Consyst Heritage Daconil Ultrex+ Aliette Sig Daconil Ult + Banner

AUDPC =1374.6 b Heritage Prostar Dac Ult Clearys 3336 Banner Maxx Fore

AUDPC =1103.4 bcd Heritage Prostar Prostar Consyst Dac Ult Chipco 26019

AUDPC = 4221

AUDPC =1011.5

Crenshaw Bent Dollar Spot Fungicide Trial Martin, 1999

AUDPC =1195.3

AUDPC =855.8 Heritage- 0.2 oz Banner + DacUlt- 1 + 3.8 oz DacUlt - Consyst - 4 oz DacUlt+ Al Sig - 3.8+4 oz Banner + DacUlt - 1 + 3.8 oz

AUDPC =822.5 DacUlt - 3.8 oz Eagle + DacUlt - 0.4+3.1 oz Fore + Eagle - 6 + 0.34 oz Heritage - 0.2 oz Fore + Aliette - 8 + 4 oz

Dollar Spot Lesions Bermudagrass Leaves

Program 3

Results A 1 Program 2 Program 3 Program 7 Curative Program 10

Programs 2,3,7 Spray 5 Spray 6 Spray 4 Spray 2 Spray 3 Spray 1

Program 2 Fore Daconil Ultrex + Chipco Sig. Chipco 26GT Daconil Ultrex

Program 3 Daconil Ultrex + Chipco Sig. Daconil Ultrex Heritage Chipco 26GT Daconil Ultrex Chipco 26GT

Program 7 Heritage Fore Daconil Ultex Prostar Clearys 3336 Banner Maxx

Program 10 Heritage + Daconil Ultrex Daconil Ultrex Heritage Chipco Sig. + Daconil Ultrex

Program 3 Daconil Ultrex Heritage Chipco 26GT Daconil Ultrex + Chipco Sig. Chipco 26GT Daconil Ultrex

Difference Between Varieties

Difference Between Varieties

Difference Between Varieties

Difference Between Varieties

R. solani

Conclusions Preventative programs more effective than curative programs Fungicide selection and timing critical Rhizoctonia zeae most likely to occur during hottest times of the summer Varieties of bentgrass do differ