Progress 10/01/08 to 09/30/09
Outputs
Progress Report Objectives (from AD-416) Targeting weeds at an early stage of invasion for biocontrol is a cost- effective strategy implemented successfully in South Africa. As part of this strategy, during FY 2009, SABCL has developed specific natural enemies mainly for Cardiospermum grandiflorum (Balloon vine) and Anredera cordifolia (Madeira Vine) in Argentina. 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. Research will cover the following areas: 1.Natural host range; 2. Life cycle and phenology of selected species and their associated natural enemies; 3. Host-specificity studies and potential impact; 4. Live insects studies in quarantine in South Africa. Significant Activities that Support Special Target Populations Balloon vine Interspersion open-field test. The two field plots set up in Misiones province in April 2008 were visited in September and December 2008, and in March and May 2009; plants were examined for the presence of insects. In plot 1, the fungal pathogen Phyllacora rimulosa was found infesting the three Cardiospermum species while the rust Puccinia arechavaletae, only C. grandiflorum and C. halicacabum. The phytophagous insects Lisseurytomella flava and Chlorostrymon simaethis sarita were found infesting the three Cardiospermum species, which is in correspondence with field surveys conducted throughout northern Argentina. Moodnopsis n. sp. near perangusta was found feeding on C. grandiflorum and C. corindum, while C. tuberculipennis and Gargaphia sp. were found only on C. grandiflorum. Although plots 1 and 2 were set up at the same time (April 2008), plants in plot 2 were severely retarded by frosts. This could be one of the reasons for the fewer natural enemies found. So far, results indicate that Gargaphia sp. and C. tuberculipennis are the only natural enemies found exclusively on Balloon vine plants. Madeira vine Adults of Plectonycha correntina were reared and 15 F1-adults were shipped to quarantine facilities at PPRI Pretoria. Larvae of a leaf- feeding moth were found in Misiones province and were tentatively identified as Loxomorpha cambogialis Guenee (Lepidoptera: Crambidae) by USDA-ARS-SEL, Beltsville, MD. Methods used for the monitoring of this subordinate project included periodical phone calls and E-mail exchanges with Plant Protection Research Institute, Pretoria, South Africa. Also, reports were prepared and delivered to the funding agency as requested.
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Progress 10/01/06 to 09/30/07
Outputs
Progress Report 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. 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. Significant Activities that Support Special Target Populations 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.
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Progress 10/01/05 to 09/30/06
Outputs
Progress Report 4d Progress report. Balloon vine (Cardiospermum grandiflorum): We focused on field host specificity of selected seed-feeding insects, the richest group of natural enemies associated with this weed. Also, we continued the search of new potential agents. Lisseurytomella flava Ashmead (Eulophidae: Tetrastichinae) was found feeding on the seeds of C. grandiflorum and C. halicacabum in several localities of northern Argentina. The larvae feed on the green seeds of the young fruits. So far, host records and field observations indicate that L. flava host range is restricted to Cardiospermum species. Seed feeders. Nine sites where C. grandiflorum coexisted with other Sapindaceae were selected and visited. Preliminary results revealed the presence of Cissoanthonomus tuberculipenis Hustache (Coleoptera: Curculionidae), Chlorostrymon simaethis sarita (Skinner) (Lepidoptera: Lycaenidae) and Phycitinae #1 (Lepidoptera: Pyralidae). Four Curculionidae (Coleoptera)
species were found feeding on different Sapindaceae. C. tuberculipennis was found feeding only on C. grandiflorum seeds. In addition, three other curculionid species, Achia affinis, Achia ancile and Achia n. sp. were obtained from fruit samples of S. fuscifolia, S. laruoteana and U. ulmacea respectively. The available field host specificity data indicates that each weevil is associated with only one Sapindaceae species, where C. tuberculipennis is restricted to C. grandiflorum. The hairstreak moth, C. simaethis sarita, was the most common and abundant of the seed-feeding Lepidoptera. Adults emerged from C. grandiflorum, C. halicacabum var. microcarpum and Urvillea ulmacea. The damaging capacity, abundance, and easy rearing has encouraged PPRI researchers to culture the insect in quarantine facilities. Results of host specificity tests and studies conducted at SABCL will indicate its potentiality as biological control agent in South Africa. Phycitinae #1 was found feeding only on C.
grandiflorum. Other Lepidoptera larvae were found feeding on seeds of U. ulmacea and S. laruotteana but, unfortunately, no adults were obtained. Pompom weed (Campuloclinium macrocephalum): Preliminary information on the presence, abundance, and damage of Liothrips sp. (Thysanoptera) on leaves and stem tips of C. macrocephalum was confirmed. The thrips potential is being considered because of its apparent specificity on C. macrocephalum. Laboratory specificity tests. Adult oviposition preference was initially evaluated on four species of Asteraceae (C. macrocephalum, Ageratum conyzoides, Conyza albida and Bidens subalternans by running a no-choice test in outdoor conditions). Oviposition preference was also evaluated on C. macrocephalum and A. conyzoides under controlled environmental conditions. No-choice and paired-choice tests were conducted. Results. In the no-choice test, Liothrips showed an extremely high oviposition preference for C. macrocephalum. In the tests conducted under
controlled conditions, Liothrips sp. showed a total oviposition preference for its natural host. Field tests: Asteraceae species growing in the vicinity of infested C. macrocephlum plants were examined for the presence of Liothrips sp. No specimens or damage was observed. This preliminary field data indicates that C. macrocephalum is the only natural host of Liothrips sp. Barbados gooseberry (Pereskia aculeata): Special attention was given to Maracayia chlorisalis (Lepidoptera: Crambidae: Pyraustinae) to establish a culture. Despite larval activity was recorded in many sites, few larvae and pupae were collected and no adults were obtained. Consequently, a culture M. chlorisalis was not possible. Mesquite (Prosopis spp.): Since the exportation of the biocontrol agent Coelocephalapion gandolfoi (Coleoptera: Apionidae) to quarantine facilities at the PPRI, Pretoria, South Africa in 2005, no further investigations have been conducted at SABCL.
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