Janus compressus F. and Tetrops praeusta L.: Little known fruit pests in Serbia

Abstract

In recent years, in more localities in Serbia, on apple and pear plantations, drying of primary shoots has been registered. Agents of this drying are two harmful insect species insufficiently known in Serbia, pear shoot wasp Janus compressus and fruit longhorn beetle Tetrops praeusta. Injuries on primary shoots emerge first in the period of oviposition and then during the development of larval feeding inside the primary shoot. In the beginning apexes wilt and stoop downward, and later darken and necrotize. Later during vegetation leaves on primary shoots dry and fall, so primary shoots, i.e. twigs remain naked and dry. Damages are particularly significant in plantations and on young plants. Attack symptoms remind of the fire blight symptoms caused by bacteria Erwinia amylovora. This paper discribes basic morphological traits of both species, their life cycle and distribution in Serbia.

Poslednjih godina, na većem broju lokaliteta u Srbiji, u zasadima jabuke i kruške, registrovano je sušenje mladara. Prouzrokovači ovog sušenja su dve, za Srbiju nedovoljno poznate štetne insekatske vrste, osa kruškinih mladara Janus compressus i strižibuba voćaka Tetrops praeusta. Oštećenja na mladarima nastaju prvo u periodu ovipozicije, a zatim tokom razvoja larve koja se hrani u unutrašnjosti mladara. U početku vrhovi mladara venu i povijaju se na dole, a zatim potamne i nekrotiraju. Kasnije tokom vegetacije listovi na mladarima se suše i opadaju, pa mladari, tj. grančice ostaju ogoljene i sasušuju se. Štete su posebno značajne u rasadnicima i na mladim biljkama. Simptomi napada podsećaju na simptome bakteriozne plamenjače prouzrokovane bakterijom Erwinia amylovora. U ovom radu su opisane osnovne morfološke karakteristike obe vrste, njihov ciklus razvića i rasprostranjenost u Srbiji.