The impact of the low doses of
ionizing radiation has been a matter of important consideration over the last
few years. The present work investigates the chromosomal aberrations induced by
two doses of radiations; a low dose as 10 Gy and a high dose as 60 Gy gamma
radiation on the male germ cells of the green vegetable stink bug, Nezara
viridula. The karyotype of the holocentric chromosomes at meiotic metaphase
I for the non-irradiated and the irradiated adult males were examined by light
microscope. Fourteen chromosomes were observed at the meiotic metaphase I of
the non-irradiated spermatogonial cells. The typical diploid number of the 14
chromosomes was (12A + XY). Most of the cells showed six rod-like autosomal
bivalent chromosomes and one pair of sex chromosomes. In some cells five to
four bivalent rod-like with one or two ring chromosomes were recorded.
Chromosomal aberrations were detected at meiotic metaphase I in the germ cells
of the irradiated testes with 10 Gy dose. Translocation and aggregation
(sticky) chromosomes with a tetravalent structure as well as B-Chromosomes were
observed.  Chromosomal fragmentations
were also demonstrated in few gonial cells. At high dose as 60 Gy of gamma
radiation, chromosomal fragmentations were only observed in the cells. The
results confirm that low dose 10 Gy gamma radiation has induced chromosomal aberrations
in the irradiated spermatogonial cells of the green vegetable stink bug, N.
viridula. The present work provides part of the cytogenetic background
necessary for the development of biological control protocols and future
development of the sterile insect technique and support for the potential
application of inherited partial sterility as an innovation in insect control
against this economically important pest species.