020 Phytotoxic Properties of Soybean Oil and Emulsifiers on Miniature Roses

Abstract

Previous research indicated that soybean oil effectively controlled insects and mites on ornamentals. In some conditions, emulsified oil sprays have also been shown to cause phytotoxicity. The objective of this research was to determine which soybean oil emulsions and/or emulsifiers produced the least amount of phytotoxicity on miniature roses. Greenhouse-grown `Fashion' (pink), `Fiesta' (fuchsia), `Tender' (white), `Orange' (red), and `Bronze' (yellow) miniature roses in trade-gallon containers were sprayed once in late fall 1998. Treatments included: 1) water (control); 1% concentrations of commercial soybean oil formulations of 2) Soygold 1000 and 3) Soygold 2000 (Ag Environmental Products), 4) Emulsion A and 5) Emulsion B (Michigan Molecular Institute); 1% soybean oil emulsified with 6) 0.1% Ballistol (F.W. Klever, Germany), 7) 0.1% ERUCiCHEM (International Lubricants), 8) 0.1% ERUCiCHEM mixed with 0.01% lecithin (Chem Service), 9) 0.1% soy methylester (Michigan Molecular Institute), 10) 0.06% Atlox and 0.04% Tween (ICI Americas), 11) 0.1% E-Z-Mulse (Florida Chemical Company), or 12) 0.1% Latron B-1956 (Rohm & Haas). The emulsifiers were also tested alone for phytotoxicity to rose foliage. None of the emulsifiers caused significant damage. Soybean oil emulsified with E-Z-Mulse did not cause significant phytotoxicity as indicated by chlorosis of foliage. The commercially prepared Emulsion A, Soygold 1000 and Soygold 2000 caused slight phytotoxicity. Emulsion B and soybean oil plus Latron B-1956 caused moderate phytotoxicity. The soybean oil-Ballistol emulsion was the most phytotoxic. Cultivars varied in sensitivity (P < 0.01) to soybean oil emulsions (listed in the order of increasing sensitivity): `Orange', `Fashion', `Bronze', `Fiesta', and `Tender'.