Cabbage looper (CL): Trichoplusia ni (Hübner) Beet armyworm (BAW): Spodoptera exigua (Hübner) The objective of this study was to evaluate the efficacy of two new compounds compared with industry standards for control of two important lepidopterous larvae species on fall broccoli in desert growing conditions. Broccoli was direct seeded on 9 Sep at the Yuma Valley Agricultural Center, Yuma, AZ into double row beds on 42-inch centers. Stand establishment was achieved using overhead sprinkler

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... tion, and irrigated with furrow irrigation thereafter. Plots were two beds wide by 50 ft long bordered by two untreated beds. Four replications of each treatment in a RCB design. Foliar applications were made with a CO 2 -operated boom sprayer operated at 60 psi and 27 gpa. A directed spray (approximately a 75% band, with rate adjusted for band) was delivered through three TX-12 ConeJet per bed. Formulations and rates for each compound are provided in the tables. Penetrator Plus was added to the Avaunt, Proclaim and BAS320021 treatments at 0.5% v/v, and Dyne-Amic was added to the Pyridalyl and Success treatments at 0.125% v/v. Sprays were applied on 2, 10 and 24 Oct. Evaluation of lepidopterous larvae control was based on the number of live larvae per plant sampled from each replicate. The plots were sampled before the first application, and at various days after treatments were applied. Ten plants per plot were destructively sampled on each sample date. The sample unit consisted of examination of whole plants for presence of small and large BAW and CL larvae. For BAW, larvae were considered small if <5 mm in length, large >5mm. For CL, larvae were considered small if <10 mm, large if > 10 mm. Treatment means were analyzed using a 1-way ANOVA and means separated by a protected LSD (P ≤ 0.05).