20140730a.pdf IR-4 Ornamental Horticulture Program Research Report Cover Sheet Trial: 2014 TX Researcher(s) Mengmeng Gu (TX A Texas AgriLife Extension Service Affiliation: Department of Horticulture Sciences 2134 TAMU College Station PhoneNumber: 979-845-8567 mgu@tamu.edu Email: ProjectTitle: Protocol #: PR# 27333 29991 TX 77843 Acibenzolar Crop Safety 14-003 Research Target Crop/Plant Product EPA Reg. # Production Site Phytotoxicity Pothos Insimmo 100-922 Phytotoxicity Epipremnum aureum Acibenzolar-S-methyl Syngenta Phytotoxicity Sunflower Insimmo 100-922 Phytotoxicity Helianthus sp. Acibenzolar-S-methyl Syngenta ProjectTitle: Protocol #: Status Field Container C Field Container C Benzovindiflupyr + Azoxystrobin (A18126B) Crop Safety 14-003 PR# Research Target Crop/Plant Product 31594 Phytotoxicity Phytotoxicity Pothos Epipremnum aureum Mural (A18126B) WDG Benzovindiflupyr + Azoxystro Syngenta Greenhouse C Field Container C Field Container C 31505 31757 Phytotoxicity Sunflower Mural (A18126B) WDG Phytotoxicity Helianthus sp. Benzovindiflupyr + Azoxystro Syngenta Phytotoxicity Phytotoxicity Bee Balm Monarda didyma Mural (A18126B) WDG Benzovindiflupyr + Azoxystro Syngenta ProjectTitle: Protocol #: PR# 31740 31746 EPA Reg. # Production Site - Status Difenconazaole + Azoxystrobin (A13703G) Crop Safety 14-003 Research Target Crop/Plant Product EPA Reg. # Production Site Phytotoxicity Aster Alibi Flora (A13703G) SC Phytotoxicity Aster sp. Difenconazole + Azoxystrobi Syngenta - Phytotoxicity Phytotoxicity Bee Balm Monarda didyma Alibi Flora (A13703G) SC Difenconazole + Azoxystrobi Syngenta Status Field Container C Field Container C Project Report: 2014 IR-4 SOR Ornamental Project 14-003 New Disease Products CS-Foliar Mengmeng Gu, PhD, Assistant Professor/Extension Specialist, Department of Horticultural Sciences, Texas A&M AgriLife Extension, College Station, TX mgu@tamu.edu Objective: Determine phytotoxicity for foliar fungicides on various ornamental horticulture plants. Plant materials: Liners of aster (Aster ‘Wood Pink’, sunflower (Helianthus ‘Table Mountain’), and bee balm (Monarda ‘Pink Supreme’) in 72-tray were obtained from Emeral Coast Growers (Pensacola, FL), pothos (Epipremnum aureum) in 4” pots were obtained from Weatherford Farms and Greenhouses (Stafford, TX), and all plants were potted in 6” azalea pots on April 4, 2014 with peat-based substrate (BM 6; Saint-Modeste, QC, Canada). All plants designated for ‘Field Container’ experiments were placed under full sun conditions with late afternoon shade from adjacent greenhouse, except that pothos in ‘Field Container’s experiment were placed under 50% shade. Plants were hand watered as needed. Fungicide treatments: All plants were grown in a glasshouse before being subjected to fungicide treatments listed in Table 1 based on IR-4 Protocol #: 14-003 New Foliar Disease Products Crop Safety. Ten replicates of each plant in each PR Number (Table 1) were arranged in a randomized complete block design. Three foliar applications were made on May 20, June 3, and June 17 according to rates in Table 1. Measurements: Initial growth index (GI; GI=plant height/2 + (plant width1+plant width2)/4) was measured for all plants on May 20, except for pothos. Final GI of all plants except pothos was measured on June 24, 2014. For pothos, a total of five plants were harvested at substrate surface on May 152014 for initial dry weight, and five plants from each treatment were harvested at substrate surface on June 24, 2014 for final pothos DW. Phytotoxicity was recorded at 7 days after each of three fungicide applications (May 27, June 10 and June 24). Pictures of representative plants from each treatment were taken on June 24, 2014. Results: There was no significant difference among the initial or final growth index (or dry weight) of plants in each PR Number (Table 1). Some plants did not grow significantly during the trial, which was probably due to the intensively hot conditions under Texas summer. No phytotoxicity was observed on any of the treatments, which were documented in Figure 1-3. Table 1. Initial and final growth index (GI) of aster, bee balm, and sunflower, and initial and final dry weight of pothos after three foliar applications of foliar fungicides based on Protocol#14-003. PR Number 31740 31746 31757 Crop Aster Aster 'Wood Pink' Bee Balm Monarda Didyma 'Pink Supreme‘ Bee Balm Monarda Didyma 'Pink Supreme’ Alibi Flora (A13703) SC Difenconazole + Azoxystrobin Field Container Rates oz/100gal) 0 8 14 28 0 8 14 Mural (A18126B) WDG Benzovindiflupyr + Azoxystrobin Field Container 28 0 4 7 Product Alibi Flora (A13703) SC Difenconazole + Azoxystrobin Production Site Field Container Initial GI* 19.4 19.5 19.1 19.2 23.1 22.9 22.6 Final GI 24.6 25.0 25.4 25.7 22.7 22.6 19.65 23.7 22.1 21.0 21.8 22.7 19.8 20.9 21.6 14 22.3 22.3 0 35.0 Pothos Insimmo 0.25 36.4 Field 27333 Epipremnum Acibenzolar-S19.8 Container 0.5 33.2 aureum Methyl 1 35.8 0 36.3 Mural (A18126B) Pothos 4 39.0 WDG 31594 Epipremnum Greenhouse 19.8 Benzovindiflupyr 7 37.7 aureum + Azoxystrobin 14 41.3 0 25.5 23.5 Sunflower Insimmo 0.25 23.7 24.6 Helianthus Field 29991 Acibenzolar-S'Table Container 0.5 25.4 24.7 Methyl Mountain' 1 25.0 24.3 0 24.7 23.1 Sunflower Mural (A18126B) 4 23.4 23.7 Helianthus WDG Field 31505 'Table Benzovindiflupyr Container 7 23.8 22.9 Mountain' + Azoxystrobin 14 23.4 23.1 * GI=plant height/2 + (plant width1+plant width2)/4. GI was not measured for Pothos. For pothos, the presented data were shoot dry weight, and not GI. A total of five plants were harvested at substrate surface on May 15 2014 for initial dry weight, and five plants from each treatment were harvested at substrate surface on 24 June 2014 for final pothos DW. All GI data were collected on the same day that pothos were harvested for DW measurement. Figure 1. Aster and bee balm after three applications of foliar fungicides based on Protocol#14-003. There was no phytotoxicity on any rates of Alibi Flora for each of three ratings at 7 days after each application. Figure 2. Bee balm, sunflower and pothos after three applications of foliar fungicides based on Protocol#14-003. There was no phytotoxicity on any rates of Mural for each of three ratings at 7 days after each application. Figure 3. Sunflower and pothos after three applications of foliar fungicides based on Protocol#14-003. There was no phytotoxicity on any rates of Insimmo for each of three ratings at 7 days after each application.