ZOYSIAGRASS (ZOYSIA SPP.) RESISTANCE TO FALL ARMYWORM (SPODOPTERA FRUGIPERDA): POLYPHENOLS AND FLAVONOIDS ¿ COMPONENTS OF RESISTANCE

T.C. Hale, R.H. White, J.A. Reinert, M.E. Snook
Leaf tissue collected from six zoysiagrass (Zoysia spp.) cultivars was analyzed for polyphenols and flavonoids by high performance liquid chromatography (HPLC). The experiment investigated the effects of sampling date and N fertilization rate on green leaf chemistry of zoysiagrass and their relationship to fall armyworm (FAW) [Spodoptera frugiperda (J. E. Smith)] resistance. Six zoysiagrasses cultivars {Crowne= (Z. japonica Steud.), Palisades= (Z. japonica Steud.), El Toro= (Z. japonica Steud.), Meyer= (Z. japonica Steud.), Cavalier= [Z. matrella (L.) Merr.], and 'Emerald' (Z. japonica Stued. × Z. tenuifolia Willd. ex Trin.)} were planted in a randomized split-plot design with 4 replicates using cultivars as the main plot and 12.2 and 48.9 kg of N ha-1 month-1 [(NH4)2SO4] as the split plots. Flavonoid concentration decreased as the amount of applied N increased. Flavonoid concentration was greatest in June and steadily declined throughout July and August. Two unidentified flavonoids (luteolin-glycosides) were consistently associated with FAW mortality when analyzed by stepwise regression techniques. Unidentified luteolin 3 had an inverse relationship with mortality, while unidentified luteolin 9 was positively correlated with mortality. Additional research is needed to determine if the concentration of luteolins found in resistant zoysiagrasses are sufficient to cause biocidal activity in FAW.
Hale, T.C., White, R.H., Reinert, J.A. and Snook, M.E. 2008. ZOYSIAGRASS (ZOYSIA SPP.) RESISTANCE TO FALL ARMYWORM (SPODOPTERA FRUGIPERDA): POLYPHENOLS AND FLAVONOIDS ¿ COMPONENTS OF RESISTANCE. Acta Hort. (ISHS) 783:507-518
http://www.actahort.org/books/783/783_52.htm
host plant resistance, Zoysia japonica, Zoysia matrella, Spodoptera frugiperda, turfgrass, eriophyid mites, pest management
English

Acta Horticulturae