Studies were conducted in 2013-2014 to quantify attraction, feeding, and mortality of male oriental fruit flies, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), to STATIC Spinosad ME a reduced-risk male annihilation treatment (MAT) formulation consisting of an amorphous polymer matrix in combination with methyl eugenol (ME) and spinosad compared with the standard treatment of Min-U-Gel mixed with ME and naled (Dibrom). Our approach used a behavioral methodology for evaluation of slow-acting reduced-risk insecticides. ME treatments were weathered for 1, 7, 14, 21, and 28 d under operational conditions in California and Florida and shipped to Hawaii for bioassays. In field tests using bucket traps to attract and capture wild males, and in toxicity studies conducted in 1-m(3) cages using released males of controlled ages, STATIC Spinosad ME performed equally as well to the standard formulation of Min-U-Gel ME with naled for material aged up to 28 d in both California and Florida. In laboratory feeding tests in which individual males were exposed for 5 min to the different ME treatments, mortality induced by STATIC Spinosad ME recorded at 24 h did not differ from mortality caused by Min-U-Gel ME with naled at 1, 7, 14, and 21 d in California and was equal to or higher for all weathered time periods in Florida during two trials. Spinosad has low contact toxicity, and when mixed with an attractant and slow release matrix, offers a reduced-risk alternative for eradication of B. dorsalis and related ME attracted species, without many of the potential negative effects to humans and nontargets associated with broad-spectrum contact insecticides such as naled.

Difficulties in controlling the supply of iron to citrus trees when grown in soil led the authors to use of nutrient solutions for this study. Twenty-four nucellar navel orange trees were grown for eleven years in individual tanks of nutrient solutions, out of doors. Eight of them were maintained at high-iron levels by regular additions of iron sulfate to the nutrient solutions. The remaining trees became iron deficient at various rates. Analyses of standard leaves, picked in the early fall season, provided a measure of the changing level of iron nutrition for each tree from year to year. The results show that, when the concentration of iron in standard leaves was 30 ppm or less for two consecutive years, the rate of tree growth and the numbers of fruit produced diminished. Fruit sizes were unaffected, except that in some years, fruit on irondeficient trees were somewhat larger than those on trees supplied with iron. Chemical differences in the fruit were slight except for iron concentrations. Fruits were lighter colored in iron-deficient trees. Iron deficit was also accompanied by loss of leaves and dieback of twigs. This obvious symptom may provide a useful measure of the severity of iron deficit.