Fauna and ecology of mining flies of the genus Phytomyza (Diptera: Agromyzidae) in Nagorno-Karabakh
The aim of the work was to study the species composition, as well as some behavior, ecology, biology issues, species distribution of the genus Phytomyza and research of cultivated and wild host-plants in Nagorno-Karabakh. Infected plant leaves, larvae and pupae of the mining flies collected from different geographical zones of Nagorno-Karabakh were served as scientific material. Species composition was determined under laboratory conditions after imagoes hatching from mines with larvae and pupae. Three species were identified, they belong to the genus Phytomyza : Phytomyza horticola (Goureau, 1851), Ph. plantaginis (Robineau-Desvoidy, 1851) and Ph. lappae (Goureau, 1851). The polyphagous Ph. horticola species infect mainly the plant species of the families Brassicaceae, Asteraceae and Cucurbitaceae. The monophagous Ph. plantaginis and Ph. lappae species accordingly infect Plantago mayor and Arctium lappa plant species. The paper presents features of the genus, morphology and biology of imago, ecological characteristics of their larvae and pupae, mines, intensity and extensiveness of plant infection. The studies have shown that despite the similarity of some species of the genus in terms of external morphological characteristics, they differ in environments of pupal development, and more accurate identity of the species is determined by studying the reproductive organs. Among the studied species, the mines formed on the lower surface are always longer than the mines on the upper surface of the leaf blade. Methods of variance analysis showed that sexual dimorphism is most expressed among Ph. horticola . Taking into account the significant damage caused by the larvae of the Ph. horticola species to a group of vegetable crops, especially to the onion plant ( Allium cepa ), it can be included in the list of onion pests. The high damage to the leaves of weed plants by Ph. horticola larvae indicates the prospects of using this miner in the fight against weeds.