Kunzea

Abstract: Puccinia psidii Wint. is a very unusual rust with an extremely wide host range within the Myrtaceae. The fungus currently occurs only in South and Central America, the Caribbean, and Florida, where it causes disease of both indigenous and introduced species. The hosts of most economic importance are Eucalyptus species, grown as plantations on a very large scale, especially in Brazil. The rust is a serious threat to tropical, sub-tropical, and possibly temperate plantations in Australia, and in other regions world-wide. In Australia, there is an additional threat to native vegetation as many communities are dominated by Myrtaceae. A collaborative project between Australia, Brazil, and South Africa aims to assist in the management of the disease by screening a wide range of myrtaceous genera for susceptibility to the disease, mapping areas in South America, Australia, and other areas globally in eucalypt-growing regions for potential disease hazard, and developing molecular tools for detecting the presence of P. psidii in seed, pollen, and other germplasm. A total of 26 Eucalyptus species of many provenances have so far been tested for rust resistance, along with four Melaleuca species and one species of each of Angophora, Callistemon, Kunzea, Lophostemon, and Syncarpia. Additional genera across the main groups of the family are currently being screened for susceptibility. Hazard maps, which can be used as a measure for evaluating risks associated with germplasm movements have been generated for South and Central America and Australasia. In addition, a highly sensitive detection system has been developed by which rust contamination has been detected in samples of asymptomatic vegetative eucalypt material, seed, and pollen, and on the surfaces of clothing and equipment. * Paper presented at the 8 International Congress of Plant Pathology, 2-7 February 2003, Christchurch, New Zealand. New Zealand Journal of Forestry Science 33(3): 420-428 (2003) Tommerup et al. — Guava rust in Brazil 421

Abstract: Twenty-one species of leaf-feeding thrips from Australia in the genus Scirtothrips , including eleven newly described species, are here distinguished with an identification key and illustrations. Some of these species are host-specific, but with diverse host associations, including tree ferns, two different genera of cycads, Acacia , Allocasuarina , Brachychiton, Hakea , and Kunzea . Two new speciesgroups, based on S. albomaculatus and S. akakia , are distinguished, both with several species on endemic species of Acacia . In contrast, other species are highly polyphagous, and some of these are crop pests, including S. dorsalis and S. aurantii , the South African citrus thrips that was introduced recently to Queensland. Three species are part of the northern tropical fauna, S. dorsalis , S. dobroskyi , and S. tenor , whereas most of the others are endemic to the arid areas of Australia. The monotypic genus Labiothrips Bhatti & Mound is synonymised with Scirtothrips Shull, and the New Zealand species S. pan Palmer & Mound is removed from the Australian list as a misidentification. The species recognised are: S. akakia sp.n., S. albomaculatus Bianchi, S. astibos , sp.n., S. aurantii Faure, S. australiae Hood (= auricorpus Girault, syn.n .), S. casuarinae Palmer & Mound, S. dobroskyi Moulton, S. dorsalis Hood, S. drepanofortis sp. n., S. eremicus sp.n., S. frondis sp.n., S. helenae Palmer & Mound, S. inermis Priesner, S. kirrhos sp.n., S. litotes sp.n., S. longipennis (Bagnall), S. moneres sp.n., S. pilbara sp.n., S. quadriseta sp.n., S. solus sp.n., and S . tenor (Bhatti & Mound).

Abstract: Four acyl-phloroglucinol derivatives showing antiviral activity have been isolated from Kunzea sinclairii and Kunzea ericoides (Myrtaceae) from New Zealand. The structures of these compounds were deduced from analysis of spectral data. Two of these compounds, 1 and 2, are the isomers of isobutyryl methoxyresorcinol. The two new compounds, 3 and 4, were isolated as a mixture and determined to be 4-cyclohexene-1,3-dioxo-5-hydroxy-2,2,6,6-tetramethyl-4- (1-[2,6-dihydroxy-4- methoxy-3-(3-methyl-1-oxobutyl)phenyl]-3-methylbutyl) and its 2-methyl-1-oxopropyl analogue, respectively.