Actual phytosanitary state of park cenoses of the Southern Coast of the Crimea

The objective of the research is to assess the species diversity of entomoacarocomplex of phytophagans of park cenoses of the Southern Coast of the Crimea, to identify dominant species and to determine the factors controlling their number and distribution. The research methods are the following: biological survey, visual inspection, pheromone traps, the definition of species by morphological characteristics. During the period from 2005 to 2018, the species composition of the entomoacarocomplex of phytophagans of ornamental crops in the parks of the Southern Coast of the Crimea has changed significantly under the influence of abiotic factors, anthropogenic load, development of tourism, business relations, increase in introduction works, change in the assortment of pesticides. Currently, the fauna of arthropods in the parks is represented by 55 species of phytophagans from 7 orders and 23 families, which include aboriginal, introduced and invasive species. Systematically phytophagans are sorted as follows: order Homoptera - 30 species, Hemiptera - 2, Hymenoptera - 1, Lepidoptera - 10, order Diptera - 2, Coleoptera - 7, Acariformes - 3 species. Homoptera order remains the most numerous in the number of species, which accounts for 54.5% of the total number of phytophagans. The dominant species among the local species are euonymus scale, viburnum scale, osier spittlebug, pistache marginal gall aphids, twospotted spider mite. Uncontrolled import of planting material from the European countries has led to the emergence of invasive species with high bio-potential, environmental plasticity, aggressiveness and causing invasions in the parks of the Southern Coast, which leads to the death of plants of local flora and introducents. Currently, 12 invasive species of pests have adapted on the territory of the Crimean parks. The process of invasions continues; it will lead to significant changes in the species composition of phytophagans.

Seasonal Occurrence, Phenological Indicators and Mortality Factors Affecting Five Scale Insect Species (Hemiptera:Diaspididae, Coccidae) in the Urban Landscape Setting

Proper timing of pesticide applications is paramount when attempting to control scale insects (Hemiptera: Diaspididae, Coccidae) that are important pests of landscape plantings. Use of degree-days and phenological indicators can better time the applications and reduce the number of treatments. Seasonal appearance of five species of scale insects in the urban landscape along with flowering phenology of 40 plant species were systematically monitored during 1997, 1998, 1999 and 2000 in Athens, GA. Degree-day calculations for predicting first-generation crawler emergence were attained by two methods: use of standard-base or an experimentally determined base temperature. Predictions using a standard temperature resulted in high year-to-year variance. Use of a model-derived base temperature reduced the variance for degree-days needed for first crawler emergence. Mean base temperatures for European fruit lecanium, Indian wax scale, obscure scale, euonymus scale, and tea scale were, respectively, 12.78, 12.78, 5.0, 3.89, and 5.0°C. The range in degree-days required for first crawler emergence of each species using first the experimentally derived base, or the standard base temperature of 10.56 were 1184 to 1296 or 1064 to 1622 for European fruit lecanium; 846 to 1014 or 1150 to 1380 for Indian wax scale; 1246 to 1268 or 515 to 566 for obscure scale; 1366 to 1492 or 313 to 597 for euonymus scale; and 526 to 1502 or 202 to 776 for tea scale. Natural enemy complexes observed in association with each of the scale species are discussed.