Resource Information

     
Evaluation of Granular Insecticides Against Aphids on Chrysanthemum, 1993  
     

By: A. H. Hara, T. Y. Hata, and R. T. Kaneko

Beaumont Agri. Res. Center, University of Hawaii-Manoa, 461 W. Lanikaula St., Hilo, Hawaii 96720, Phone (808) 935-2885

HOST: Chrysanthemum: Chrysanthemum morifolium
'White Diamond'
TARGETED PEST: Chrysanthemum aphid: Macrosiphoniella
sanborni (Gillette)


EXPERIMENTAL PROCEDURE
Phytotoxicity and efficacy trials were conducted from 29 Sep through 6 Nov 1993 on potted chrysanthemums at a commercial chrysanthemum farm in Hilo, HI. Cuttings (2.5 inch) were planted in 6 inch plastic pots containing a 3:1:1 mixture of peat, vermiculite and perlite and maintained by standard commercial growing practices. Treatments consisted of 4 replicates (1 pot per replicate, 3 plants per pot) arranged randomly on a bench in a fiberglass greenhouse. Insecticide granules were applied once 21 days after planting and immediately watered after treatment. Insecticides were evaluated for efficacy at the following rates: NTN 2.5 G 0.03g AI/pot, Temik 10G, 0.045g AI/pot; phytotoxicity was evaluated at: NTN 2.5G, 0.03g AI/pot, 0.06g AI/pot, 0.12g AI/pot, Temik 10G, 0.045g AI/pot. Both efficacy and phytotoxicity trials included a untreated control. For evaluation of efficacy, data on the number of aphids per terminal (bud and first three leaves) were taken weekly beginning 14 Oct through 6 Nov. Plants were observed for phytotoxicity weekly.

RESULTS
NTN 2.5G and Temik 10G significantly reduced aphids with no significant difference between both insecticides. Only alate adults were observed in the NTN treatment. Phytotoxicity characterized by necrotic leaf tips occurred in all insecticide treatments including the growers conventional treatment of Temik 10G. Injury from Temik 10G was comparable to the lower rate of NTN (0.03 g/pot). The severity of injury from NTN increased as the rate of NTN increased. Phytotoxicity was not observed on buds or flowers.

      Aphids    
    a      
Treatment g AI/pot 14 Oct 22 Oct 29 Oct 6 Nov
NTN 2.5G 0.030 0.0 4.0b* 0.0b** 1.0b**
Temik 10G 0.045 0.0 0.3b 7.0b 12.0b
Control   150.8 224.5a 219.0a 181.8a


*, **, significant by ANOVA P<0.05, 0.01, respectively. Means followed by same letters in a column are not significantly different by Waller-Duncan K-Ratio t test, k=100.
a Data not analyzed.

PRODUCT INFORMATION

PRECAUTIONARY STATEMENT
Use pesticides safely. Follow the pesticide label. Consult with the Cooperative Extension Service or the Hawai'i State Department of Agriculture for authorized special local need registrations or additional information. The user is responsible for the proper use, application, storage, and disposal of pesticides.

DISCLAIMER
Reference to a company or product name does not imply approval or recommendation of the product by the College of Tropical Agriculture and Human Resources, Cooperative Extension Service University of Hawaii, or the United State Department of Agriculture and does not imply its approval to the exclusion of other products that may be suitable. All materials should be used in accordance with label instructions or manufacturer's directions.

Product Name: NTN 2.5G
Manufacturer's Name: Miles Inc.
Address: P.O. Box 4913, 8400 Hawthorn Road, Kansas City, MO 64120
Composition: imidacloprid 2.5%G

Product Name: Temik 10G
Manufacturer's Name: Union Carbide Agricultural Products Co., Inc.
Address: P.O. Box 12014, T.W. Alexander Dr., Research Triangle Park, NC 27709
Composition: aldicarb 10%G