Laboratory evaluation of selected spray adjuvants as ultraviolet light protectants for the nuclear polyhedrosis virus of the celery looper (Lepidoptera : Noctuidae)

Four spray adjuvants were tested in the laboratory as ultraviolet light (UV ) protectants for the nuclear polyhedrosis virus of the celery looper, Anag rapha falcifera (Kirby) (AfMNPV), against the beet armyworm, Spodoptera exi gua (Hubner). We tested a sodium lignin sulfonate (Lignosite AN(R)), two di aminostilbene disulfonic acid-derived fluorescent brighteners (Blankophor B BH(R) and Blankophor HRS(R)), and a nutrient-based feeding stimulant (Coax( R)). Lignosite AN was active as a UV protectant; Blankophor BBH, as both an enhancer and a UV protectant; Blankophor HRS, as an enhancer only, and; Co ax, as a UV protectant only. Lack of an effect of Coax as a feeding stimula nt may be due to the design of the bioassay, in which larvae were confined on small pieces of foliage. However, the practical utility of some, if not all, of these materials may be limited by the cost and/or bulk of the amoun ts required to achieve the desired effects.