Bionomija scolytus intricatus u Srbiji

Abstract

Scolytus intricatus Ratz. (Coleoptera, Scolytidae) je sekundarna vrsta koja je prisutna u hrastovim šumama na području ćele Srbije. Konstatovan je na Querrcus cerris L., Q. trojana Webb., Q. frainetto Ten., Q. petraea (Matt) Liebl., Q. daleschampii Ten., Q. pubescens Willd., Q. virgiliana Ten., Q. robur L., Q. rubra L. i Fagus moesiaca (Domin, Maly) Czeczott. U insektarijumu je odgajen i na: Q. coccifera L., Q. ilex L., Castanea saliva Mill, i Corylus colurna L. Razvija se na materijalu manjeg prečnika (1-10 cm), mada može da naseli i debla starijih stabala (25 - 30 cm). Ima dve generacije. Let imaga druge, zimujuće generacije u prirodi počinje sredinom aprila, početkom maja i traje do sredine avgusta. Imaga prve, letnje generacije, javljaju se sredinom jula i njihov let traje do kraja septembra ili početka oktobra. Međutim, u višim, planinskim predelima S. intricatus razvija samo jednu generaciju. U takvim uslovima rojenje počinje sredinom ili krajem maja i traje do sredine avgusta. Let imaga oba pola počinje istovremeno i jednakog je intenziteta tokom celog rojenja. Seksualni indeks je 0.5. Prezimljava u stadijumu larve različitog stupnja. Kako su razlike u starosti zimujućih larava velike, jasne granice u vremenu javljanja imaga prve i druge generacije ne postoje. Zato su svi stadijumi u prirodi prisutni tokom čitave vegetacije, od aprila do oktobra. Međutim, tokom zime prisutne su samo larve. Njihov zimski prekid u razviću uslovljen je isključivo niskim temperaturama.

Scolytus intricatus is a secondary species present in oak forests throughout Serbia. It is identified on Quercus cerris L., Q. trojana Webb., Q.frainetto Ten., Q. petraeu (Matt) Liebl., Q. daleschampii Ten., Q. pubescens Willd. Q. virgiliana Ten., Q. robur L., Q. rubni L. and Fagus moesiaca (Domin Maly) Czeczott. in the insectarium it has been also reared on: Q. cocci/era L., Q. ilex L., Castanea sativa Mill, and Corylus colurna L. It develops on the material of smaller diamètres (1-10 cm), although it can infest also the trunks of older trees (25 - 30 cm). It has got two generations. The commence of the flight of the second, overwintering generation in the field is in mid April, early May and flight duration is till mid August. The adults of the first, summer generation, emerge in mid July and their flight lasts till late September or early October. However, in mountanious regions S. intricatus has got only one generation. Under such conditions, they begin and keep swarming from mid May till mid August. The adults of both sexes start flying simultaneously of equal intensity in the course of swarming. Sex index is 0.5. The insect overwinters in different larval instars. Since the age differences of overwintering larvae are great, there are no specific limits in the time when the adults of the first and the second generations are about to emerge. Consequently under field conditions all larval instars are represented over the vegetative period, from April to October. However, only larvae are present in winter. The winter interruption of larval development is conditioned solely by low temperatures.