Diaspidiotus caucasicus

 

        The poplar trees which play a great role in the landscape gardening of Absheron are mostly damaged by the  Diaspidiotus caucasicus. Its larvae and female specimens sucking the sap of the poplar tree causes their drooping, changing their appearance and falling of the leaves. Sometimes covering the stock of them with large colonies they perish the plant entirely. There is less information about the biology of the pest. In Azerbaijan this pest, its parasitoids and predators, entomophages arebeing studied for the first time.
        Diaspidiotus  caucasicus is an oligophag, its larvae and female specimens live on the stocks, branches and leaves of the poplar, willow. This diaspidiotus lives in the II age larva stage in Absheron. In spring begins the growth of the larvae. In Absheron it concurs with the first and second decades of April. The growth of the female larvae ends in the first and second decades of  May. From the second decade of April the male larvae grows gradually, the antennae, appendages and wings appear. In the first half of May the male specimens begin to fly. Living for 1-2 days they mate with the female specimens and then die.
        In the II-III decade of May the female specimens have got a lot of egg cells. The first “parturiating- viviparous ” female specimens appear at the end of May, and on the first decade of June. Some larvae appear in 1-2 hours after blowing, and others “are parturiated” in the larva form. The larvae are greyish-yellow colour,  small, elongated-oval disk.  On both sides of the body and in the middle there are black spots. For the larvae are greyish-yellow colour they are hardly observed on the plant rind.
        The larvae stick on the apophysis, branches of the tree after 2-3 hours, and sometimes after more (5-7) active movement and are covered with the initial shell. The shell is greyish-white colour, the body of the diaspididae is seen clearly  under it. Then the antennae and appendages disappear, the diaspididae  nourishes with the plant sap and grow.
        Generally the larvae sticks on the branch very closely to each other, and sometimes even under the shell of mother. Just that’s why they generate great colonies on the brahcnes and apophysis. Only too small numbers of the larvae (mainly the male specimens) are observed on the thin apophysises and leaves. 
        In 20-25 days the second mature larvae appears. At this time the shells of the male and female specimens begin to differ. The shell of the females is round, and the nymphal shell of the male is ofelon gated-oval form. In this period in the bodies of the male are formed wings, appendages and antennae. The fly of the male covers in the second and third decades of June and this process continues for 15-20 days,  separate male specimens are met even in 30-40 days.
        The “first parturiating”females of the second generation are met on the second and third decades of July.  This process approximately continues till the end of September.

     

     City Zoo

     City Zoo