1a.Objectives (from AD-416)
To conduct field surveys and laboratory studies of natural enemies of Lippi (Phyla canescens).

1b.Approach (from AD-416)
Collect natural enemies of Lippia; collect and curate flora and fauna specimens; maintain and specimen database; prepare and send specimens for identification; develop methods to propagate and grow Lippia in the laboratory; develop rearing techniques and study the biology of selected natural enemies; and observe host range of specimens in the field and laboratory.

3.Progress Report
Surveys were conducted in four ecological regions of Argentina: (1) Wetland Chaco; (2) Dry Chaco and Yungas; (3) Pampas; and (4) the transition zone between Southern Chaco, Pampas and Patagonia. Phyla sp. was recorded in 57 of 106 sites, mostly east of 66º W, from sea level (Buenos Aires province) up to 2100 m (Volcán, Jujuy Province). In the northern half of region 2, pure and mixed stands of P. canescens P. poss. reptans, and several intermediate forms (hybrids?), were found. High phenotypic variations and poor key characters made it difficult to discriminate these species in the field. Elsewhere, populations found were easily identified as P. canescens. Recent studies of herbarium specimens in Argentina did not clarify the issue.

So far, 21 species of arthropods were found: four beetles, a leaf mining fly, two thrips, two micro moths and two hairy caterpillars, eriophyid mites, unidentified stem gallers, four leafhoppers, two Cercopidae and a weevil. Many fungi were found associated with Phyla spp.; some are secondary invaders (Nigrospora, Sordaria, Podospora, etc), others are clearly pathogenic (Puccinia cf. lantanae, Cercospora cf. lippiae, Colletotrichum spp.) and some others have unknown pathobiology (Fusarium sp., Bipolaris sp., Alternaria sp., Phoma sp., Phomopsis sp.).

Cercospora cf. lippiae was the most widespread among the parasitic species and causes a necrotic leaf spot which might inflict important damage to the host. There are at least three Colletotrichum spp. involved in leaf spot symptoms; one of them might be a new species. The microcyclic rust (Puccinia cf. lantanae) should be one of the candidates to be studied, but unfortunately the host seems to be Phyla reptans rather than P. canescens.

Methods used for the monitoring of this subordinate project included periodic phone calls and e-mail exchanges with Mic Julien (CSIRO Entomology European Laboratory, Montpellier, France). Also, three quarterly reports were prepared and delivered to the funding agency.