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Host range of larvae ofHymenomimanr.memor(Lepidoptera: Geometridae) was examined in quarantine to evaluate its suitability as a biological control of Brazilian peppertree,Schinus terebinthifolia. Brazilian peppertree,S. terebinthifoliais an environmental and agricultural weed from South America that had invaded many subtropical and tropical areas of the world including Florida and Hawaii, USA. Laboratory life history and quarantine host range studies ofH.memorwere conducted with no-choice feeding tests. These tests included eight species of the Anacardiaceae and one species of Sapindaceae. Larvae ofH. memorhad five to six instars with each head capsule width increasing by 1.68-X. Development time from neonate to adult was 46.7 ± 2.2 days. In host range tests, neonates completed development to the adult stage on all non-target species, exceptToxicodendron radicans. Moreover, developmental times were delayed and pupal weights were reduced for larvae fedSpondias purpurealeaves. Due to the broad host range exhibited byH. memorlarvae, this species will not be considered as a biological control agent ofS. terebinthifoliain the continental U.S.A. [ABSTRACT FROM AUTHOR]

Brazilian peppertree, Schinus terebinthifolia Raddi (Anacardiaceae) is an invasive weed of natural and agricultural areas of Florida, Hawaii, and Texas (USA). A thrips, Pseudophilothrips ichini (Hood) is being developed as a potential agent for biological control of this invasive weed. As field releases are planned, methods are needed for the mass production and to predict the impact of the thrips. Brazilian peppertree seedlings were grown in potting media amended with three fertilizer (24N-8P-16K) levels: low (0 g/l water), medium (1.8 g/l water) or high (3.6 g/l water). The greatest number of P. ichini thrips developed on the medium fertilized plants. To measure P. ichini thrips impact, we compared growth of these fertilized seedlings with or without thrips. While maintaining the number of P. ichini thrips adults constant (20 adults), we measured the impact of one or two generations of feeding. Fertilizer level had a significant effect on all plant responses. Both one and two generations of thrips significantly decreased plant height, number of branches, leaflets, leaves, and tips. Two generations of thrips feeding caused significant reductions in branch, leaf, and total biomass. Thrips feeding increased percent nitrogen in roots and decreased percent nitrogen in branches at the medium and high fertilizer levels. Percent nitrogen of field collected stems and leaves matched that of the low fertilizer level. These results suggest a medium fertilizer application is best for mass production of P. ichini thrips. Moreover, sustained damage for more than one generation of thrips feeding will have a significant impact on total biomass of S. terebinthifolia seedlings. The use of fertilized nursery sites may help in initial establishment and field mass production of P. ichini thrips. [ABSTRACT FROM AUTHOR]