Species composition, morphological and eco-biological features of mining flies (Diptera: Agromyzidae) in Nagorno Karabakh Republic

Mining flies of the family Agromyzidae have been less studied in the South Caucasus, and such studies are being conducted for the first time in the fauna of Armenia and Nagorno-Karabakh, which determines the actuality of this study. The main purpose of the work is to study and present the species composition, morphological, ecological, biological features and morphometric data of mining flies common in Nagorno-Karabakh, as well as the intensity and extensiveness of plant infection. The study of the species composition and features of the development of weed pests will allow their use in biological methods of weed control. The study has been conducted by the authors from April 2018 to September 2020 in 6 research stations in various regions of Nagorno-Karabakh (c. Stepanakert, 39°49'N 46°45'E, c. Shushi, 39°45'N 46°45'E, vill. Ivanyan/Askeran, 39°54'N 46°47'E, vill. Nngi/Martuni, 39°47'N 46°53'E, vill. Vank/Martakert, 40°03'N 46°32'E, vill. Tyak/Hadrut 39°30'N 47°01'E). The material of the study has been plants' leaves with mines, larvae, pupae developing in them and imago of mining flies of the family Agromyzidae (Diptera) which were reared from larvae. The collection and statistical processing of the material were carried out by methods generally accepted for the family Agromyzidae. In addition to morphological features, the male genitalia, in particular, the distifallus was also studied for accurate identification of the species. During the whole study, 722 individuals (312 f and 410 $) were reared and identified. In this research we discovered 16 species of mining flies, which belong to the genera Agromyza, Ophiomyia, Amauromyza, Caycomyza, Liriomyza, Phytomyza. 45 species of host plants were identified, of which 15 belong to wild medicinal plants, 13 -cultivated plants, 5 - ornamental plants, 12 - weeds. Studies of the development of mining flies' larvae and pupae of various species in laboratory conditions revealed that at temperatures above +25°C, the period of pupal development decreases, and at temperatures below +25°C, it increases, but for each species there is an optimal temperature, beyond which the duration of development of larvae and pupae either increases or ceases. The number of host plants, as well as the data of intensity and extensiveness of infected plants indicates that the most common polyphagus species are L. sativae, L. bryoniae and Ph. horticola. According to our data, mining flies affect the following groups of plants: cultivated plants, wild medicinal, ornamental plants and weeds. On average, the intensity of various cultivated plants in the species L. sativae varies between 47-53%, the extensiveness is 58-61%, and the intensity of wild medicinal plants is 42-47%, the extensiveness is 40-42%. In the L. bryoniae species, the intensity of cultivated plants is 27-32%, the extensiveness is 49-51%, and the intensity and extensiveness of ornamental plants are 20% and 40%, respectively. All 4 plant groups were infected with Ph. horticola. On average, the intensity of cultivated plants is 3739%, the extensiveness is 53-55%, the intensity of wild medicinal plants is 78-80%, and the extensiveness is 79%. The intensity of ornamental plants varies in the range of 55-60%, the extensiveness is 70%; the intensity of weeds is 61-64%, the extensiveness is 67-69%. The most interesting in terms of plant infection are the species of mining flies belonging to the pests of weeds - A. parca, O. cunctata, Am. leonuri, C. humeralis, L. endiviae, L. congesta, L. graminivora and Ph. horticola. They can be used as biological weed control measures. The most reliable morphological features used in the species diagnosis of miners include the structural features of the male genitalia, in particular the external structure of the aedeagus. The microscopic examination has confirmed the presence of specific features of the genitalia for each species (See Fig. 2). The study of morphometric measurements of mining flies showed the presence of sexual dimorphism, consisting in the prevalence of morphometric data in females, the least expressed in the species L. brassicae. The latter is also the most variable species (See Table 2). The article can serve as a scientific basis for further study of mining flies in the region, as well as for the development of practical measures in agriculture. The article contains 2 Figure, 2 Table, 27 References. The Authors declare no conflict of interest.

Keywords

Authors

References