Rakimov, A. 2010 . Aspects of the biology, ecology and biological control of soft scale insects (Coccidae) in Australian vineyards. Ph. D. Thesis, Department of Zoology, The University of Melbourne, Melbourne, Australia. Melbourne, Australia 221 pp.

Notes: Soft scales (Hemiptera: Coccoidea: Coccidae) are a common pest in Australian vineyards. Parthenolecanium persicae, Parthenolecanium pruinosum, Coccus hesperidum, Coccus longulus, Parasaissetia nigra and Saissetia species were collected during a survey of the major grape growing regions of Australia. Parthenolecanium persicae was the most commonly collected species, followed by P. pruinosum and C. hesperidum. Parthenolecanium persicae and P. pruinosum tended to form the heaviest infestations in vineyards. Up to three coccid species were found on an individual grapevine. Approximately 7700 parasitoids and 450 predators were reared from vineyard coccids and grapevine samples infested with coccids collected from around Australia. The parasitoid Metaphycus maculipennis was the most commonly collected enemy comprising approximately 75% of all parasitoids reared from P. persicae. The wide distribution and abundance of M. maculipennis leaves no doubt that this species is the most important enemy of P. persicae in Australian vineyards. Hyperparasitoids of the genus Cheiloneurus were the most commonly collected group of parasitoids reared from P. persicae after M. maculipennis. The next most abundant species was Coccophagus lycimnia, which parasitises P. persicae, P. pruinosum and C. hesperidum. Parthenolecanium pruinosum appears to be under poor biological control in Australian vineyards, as C. lycimnia was the only primary parasitoid to be reared from this scale. The coccinellid Rhyzobius 'submetallicus' was a widespread and abundant predator of vineyard coccids. Unidentified Chrysopidae were also commonly associated with vineyard coccids. Parthenolecanium persicae had one annual generation, but gravid females were also observed during autumn, suggesting the presence of an extra partial generation. First instar P. persicae were first present in large numbers on the new vine growth in November. During subsequent months, the majority of nymphs settled on the lower surfaces of the leaves of the three most basal internodes. Male P. persicae were also collected. Metaphycus maculipennis had two annual generations and is a solitary parasitoid of P. persicae nymphs and a gregarious parasitoid of P. persicae adults. New information concerning the phenology of other vineyard coccid species and vineyard coccid enemies is also presented. The width and length of mature female P. persicae and P. pruinosum was significantly and positively correlated with the number of nymphs to emerge from a scale. On average 2352 nymphs emerged from P. persicae (range = 110 to 4343, sd = 1242.6, n = 27) and 1529 nymphs emerged from P. pruinosum (range = 106 to 3252, sd = 1079.5, n = 13). Metaphycus maculipennis reduced the fertility of P. persicae; nymphs did not emerge from approximately 85% of parasitised scales and when they did the average number of nymphs was reduced by approximately 70% in comparison to unparasitised scales. The between grapevine spatial distribution of coccids was characterised for 14 commercial vineyards. Parthenolecanium persicae and P. pruinosum tended to have an aggregated pattern of spatial distribution, and were sometimes distributed across entire vineyards. A method using cytochrome oxidase subunit I region of the mitochondrial DNA sequences for vineyard coccid identification was developed. Coccids exhibited high interspecific and low intraspecific sequence variation for the region of the COI gene examined, making this region suitable for use in species discrimination.