1a.Objectives (from AD-416)
Conduct collaborative research with the Plant Protection Research Institute (PPRI), Pretoria, South Africa, to develop biological control agents for use against mesquite and waterhyacinth.

1b.Approach (from AD-416)
Target specific biological control agents will be evaluated for their ability to destroy seeds, pods and flower buds and/or flowers. Emphasis will be placed on the seed-feeding weevil (Apion sp.), petiole mining fly (Thrypticus sp.) and sap sucker (Taosa sp.) that occurs widely in Argentina. Research will cover the following areas: 1. Natural host range; 2. Characterization of one or two unidentified Apion, Thrpticus and/or Taosa spp. that attack green mesquite pods; 3. Life cycle and phenology of selected specie(s) and their associated natural enemies; 4. Host-specificity studies and potential impact on seed production in South Africa (Permission will be obtained to introduce South African prosopis pods for preliminary preference studies in quarantine in Argentina.); 5. Live insects studies in quarantine in South Africa.

3.Progress Report
Balloon vine. A leaf-tying moth, tentatively identified as Apocera zographica (Pyralidae: Epipaschiinae), was found in several sites in northeastern Argentina. Tied leaves containing larvae were collected and brought to the lab for emergence of adults. Newly emerged adults were confined in cages containing a balloon vine potted plant. A bouquet of balloon vine flowers was provided to feed the adults. Unfortunately, only two tying larvae were obtained. In two field trips conducted in fall, no larvae were found, so probably the presence of this moth in the field is restricted to the summer. The fungus Phyllacora rimulosa was found for the first time in several sites of northeastern Argentina infesting the stems, leaves and petioles. The seed-feeding weevil Cissoanthonomus tuberculipennis weevil is the most promising agent found on this weed. Unfortunately, progress on host specificity testing is delayed due to difficulties in lab rearing. Host specificity will be evaluated in the field.

Pompom weed. Northern Argentina was surveyed to collect the most promising candidates, the flower-feeding moths, Cochylis n. sp. and Adaina simplcius and the stem-galling thrips, Liothrips tandililensis. Agents were shipped to PPRI quarantine in Hilton for host specificity studies. Barbados gooseberry. Larvae of a leaf-feeding moth were found tying and sealing leaves of P. aculeata. Occasionally, the larvae tunnelled into the young shoot tips. The cooperator Martin Hill indicated that this moth was Epipagis cambogialis with a too-broad host range and was dropped off as a possible biocontrol agent.

Cat’s claw. After the finding of the seed feeding weevil, Apteromecus notatus by the cooperator A. Witt in 2006, field observations on Macfadyena unguis-cati were initiated. Newly emerged adults obtained from dry mature pods were confined in rearing sleeves with flowers and immature pods of M. unguis-cati. Every week, pods were checked for eggs and weevils were exposed to a new set of flowers and pods. Some eggs and a burrowing larva were found between the base of the pods and the floral disc. An unidentified seed-feeding moth was also found damaging cat’s claw pods in several sites of northeast Argentina. Adults are emerging from dry dehisced pods. Specimens will be shipped for identification.

Methods used for the monitoring of this subordinate project included periodic phone calls and e-mail exchanges with Arne Witt (Plant Protection Research Institute Pretoria South Africa), Andrew McConnachie and David Simelane (PPRI Hilton, South Africa). Also, reports were prepared and delivered to the funding agency as requested.