IR-4 Ornamental Horticulture Program Research Report Cover Sheet

Transcription

1 IR-4 Ornamental Horticulture Program Research Report over Sheet Researcher(s) Scott Ludwig Affiliation: Texas A&M University TX ooperative Extension P.O. Box 38 Overton TX PhoneNumber: Trial: 2008 TX ProjectTitle: Seed Treatment - Aphids & Leps Protocol #: PR# Research Target rop/plant Product EPA Reg. # Production Site Status Green Peach Aphid Ornamental abbage, Or Aria 50SG FM Green Peach Aphid Ornamental abbage, Or DPX-E2Y hlorantraniliprole Dupont Green Peach Aphid Ornamental abbage, Or Entrust Spinosad - Dow AgroScien Green Peach Aphid Ornamental abbage, Or Regent Fipronil BASF

2 IR-4 Ornamental Horticulture Program Research Report over Sheet Researcher(s) Scott Ludwig 1, Alan Taylor 2, and risti Palmer 3 Affiliation(s): 1 Texas AgriLife Extension Service, Texas IPM Program, Overton, TX 2 ornell University, Department of Horticultural Sciences, Geneva, NY 3 IR-4 Project, Ornamental Horticulture Program, Princeton, NJ Phone Number: (903) swludwig@tamu.edu Project Title: Seed Treatment - Aphids Protocol #: PR# Research Target rop/plant Product Ornamental Kale Spinosad Ornamental Kale hlorantraniliprole Ornamental Kale Fipronil Ornamental Kale

3 Evaluation of Insecticide Seed Treatments to Manage Pests of Ornamental Kale Scott Ludwig 1, Alan Taylor 2, and risti Palmer 3 1 Texas AgriLife Extension Service, Texas IPM Program, Overton, TX 2 ornell University, Department of Horticultural Sciences, Geneva, NY 3 IR-4 Project, Ornamental Horticulture Program, Princeton, NJ INTRODUTION Film coating is a technique originally developed for the pharmaceutical and confectionery industries to produce a colored, exterior finish. This method was adapted for seed coating, whereby a liquid formulation that includes a film-forming polymer is sprayed at a controlled rate onto a tumbling mass of seeds over time to achieve a uniform deposition of materials (Taylor, 2003). The benefits of film-coating include uniform placement of materials in the correct dosage, increased worker safety (an essentially dust-free environment), and an excellent delivery for seed treatments at rates higher than those allowed using slurry techniques (Taylor et al., 2004). Seed treatments include application of certain compounds or processes, but in this paper refer to the application of insecticides to seeds. We are currently investigating the impact of film coating ornamental kale seeds with chlorantraniliprole, fipronil, flonicamid, and spinosad to suppress green peach aphid,, and diamond back moth, Plutella xylostella. In preliminary trials, flonicamid was shown to have effectively prevented aphid establishment on ornamental kale. The objective of this study was to evaluate the impact of an increased rate (2x compared to the preliminary study) and different seed coating materials to enhance efficacy against aphids. MATERIALS AND METHODS A seed lot of 'Red hidori' ornamental kale was provided by American Takii Seed o. for the project. Seeds were treated with flonicamid (ISK) at 0.5 mg ai / seed or clothianidin + imidacloprid (3:1) at 0.25 mg ai / seed (Bayer ropsciences) at the New York State Agricultural Experiment Station, Geneva, NY USA. Each seed treatment formulation was mixed with a liquid binder and applied by rotary pan technology. An encrusted coating was developed by the application of conditioning powder during the coating process. Encrustment is an intermediate between film coating and pelleting (Taylor, 2003). After treatment, seeds were dried under ambient conditions and forwarded to the senior author for entomological investigations. Two trials were conducted to evaluate the efficacy of the seed treatments against green peach aphid. In both studies the kale seeds were sown in plug trays (200 cells per tray) and grown in a research glasshouse at the Texas AgriLife Research and Extension enter at Overton. Approximately 4 weeks after seeding the seedlings were 2

4 transplanted into 15.2 cm azalea pots. The plants were naturally infested with aphids. The number of aphids on each plant was counted approximately every seven days. The plants were arranged in a randomized complete block design. The first trial was replicated 8 times and the second trial was replicated 10 times. Each treatment replicate contained 1 plant. For each trial, the mean number of aphids was subjected to analysis of variance (Randomizied omplete Block AOV, Statistix 8). Means separation was accomplished by using Fisher's least significance test (LSD) at the P<0.05 level. RESULTS AND DISUSSION A clothianidin + imidacloprid (3:1) treatment was inadvertently included in the study. This treatment resulted in significantly lower aphids populations on almost every sample period compared to the untreated control in both studies (Tables 1 & 2). This treatment was the only treatment that provided a level of aphid control that would be acceptable to ornamental producers through the length of both studies. A previous study with a lower rate of flonicamid (0.25 mg ai/ seed) resulted in significantly lower aphid populations compared to the untreated plants though 44 days after seeding. In the results presented in this study, there was no significant difference among the different flonicamid seed coating formulations. However, in the first trial, seed coating A with flonicamid resulted in a statistically lower aphid population compared to the untreated seeds on four of the sample dates between days 34 and 63 (Table 1). In the second trial, all the flonicamid treatments resulted in significantly lower aphids populations compared to the control on all sample periods (Table 2). with seed coating A could provided adequate control of aphids on kale plants during the first 6 weeks of production. This treatment needs to be evaluated under growing conditions to determine the value it will provide to growers. We are interested in the flonicamid seed treatment since it will aid in greenhouse resistance management programs because it is not cross-resistant with neonicotinoid insecticides. urrently, many ornamental cabbage and kale producers make a preventative neonicotinoid insecticide application shortly after potting with the assumption that the plants will be attacked by aphids. We are concerned about the overuse of the neonicotinoid insecticides resulting in the development of resistant pests. REFERENES ITED Taylor, A. G Seed treatments. In: Thomas, B, D. J. Murphy and B. G. Murray. Encyclopedia of Applied Plant Sciences. Elsevier Acad. Press. p Taylor, A. G., D. H. Paine, N. Suzuki, B. A. Nault and A. McFaul oating technologies for seed treatment applications. In. S. Vavrina and G. E. Welbaum, eds. Proceedings of the Sixth Symposium on Stand Establishment. Acta Horticulturae. 631:

5 AKNOWLEDGEMENTS We would like to thank Takii Seed ompany for donating the kale seeds, and Berger Peat Moss for provide the potting media. We would also like to thank David Newburn for maintaining the plants and counting all the aphids. 4

6 Table 1. Mean number of per kale plant in the first trial. Days After Seeding Nontreated 0.9±0.7 a 5.4±2.6 a 23.9±8.8 a 76.3±18.2 a 78.6±19.8 a 177.5±44.4 a 192.8±20.8 a (seed coating B) (seed coating ) 0.0±0.0 a 0.0±0.0 b 1.1±1.0 b 7.3±4.6 b 35.6±12.5 ab 84.3±15.4 bc 136.8±23.4 ab 0.1±0.1 a 2.3±1.5 ab 8.3±7.1 b 37.3±20.7 b 41.5±16.8 ab 102.6±23.5 bc 181.0±63.9 a 0.0±0.0 a 2.5±2.5 ab 6.3±4.8 b 20.6±9.3 b 51.6±25.2 ab 131.5±37.8 ab 187.9±66.6 a clothianidin + imidacloprid 0.0±0.0 a 0.0±0.0 b 0.1±0.1 b 3.4±1.5 b 13.8±10.9 b 21.0±7.6 c 34.0±5.2 b Means within columns followed by the different letters are significantly different (LSD, P<0.05). 5

7 Table 2. Mean number of per kale plant in the second trial. Days After Seeding Treatments Nontreated 13.5 ±5.4 a 59.4±17.8 a 82.2±15.9 a 412.0±54.5 a 230.1±101.5 a 994.6± ±0.0 b 2.0±1.4 b 24.1±8.8 bc 212.2±38.5 b * * 0.0±0.0 b 3.5±1.3 b 21.3±3.1 bc 260.4±37.7 b * * (seed coating B) 0.0±0.0 b 3.8±2.2 b 33.1±5.0 b 233.2±43.3 b * * (seed coating ) clothianidin + imidacloprid 0.0±0.0 b 0.0±0.0 b 2.2±0.6 c 11.3±3.7 c 83.6±11.4 b 72.8±9.0 Means within columns followed by the different letters are significantly different (LSD, P<0.05). * No additional aphid counts were made beyond 52 days after seeding for the flonicamid treatments because too many aphids were present to make the treatments relevant for use. 6