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study separately for the ponds. The nature of Heteropneustes Fossilis (Bloch). Bang. J. Zool.,
H
influence of a factor, e.g. p . on a benthos taxon 2006, 34 (1), 95-104.
frequently differed from pond to pond. However,
the fluctuations of the latter were completely The piscicidal effects of the distilled water, 50%
attributable to the combined influence of eight ethyl alcohol and 100% ethyl alcohol extracts of
principal water parameters and the fellow benthos. the fresh leaf, bark, root and dry seed of two
indigenous plants, namely Azadirachta indica
153 KHATRI, A. & SAXENA, M.M. (Dept. (A. Juss) and Barringtonia acutangula (Gaertn)
of Zoology, Dungar College, India). Ecology And were studied on the predatory fish.
Community Of Drying Sediments Of An Heteropneustes fossilis (Bloch), under normal
Ephimeral Pond In The Indian Desert. Bang. J. laboratory conditions. The mortality of the fish
Zool., 2007, 35 (2), 293-300. varied depending upon the type of plant parts,
extracts and dosages. The mortality was dose
The present study was aimed to examine the life dependent. The order of toxicity of the extracts
and living conditions in dried, semidried and wet was 100% ethyl alcohol >50% ethyl alcohol >
conditions in a village pond in the desert distilled water. The LD 50, values of A. indica
environment during summer.The moisture content, and B. acutaingula plant part extracts showed
pH and alkalinity declined away from the that B. acutanigula extracts were comparatively
submerged conditions to dried-up sediments. On more toxic than A. indica extracts, except the
the contrary, chlorides, salinity and EC increased leaf extracts. Of the two indigenous plant
with the drier conditions. The sediments from such piscicides. B. acutangula seed extract proved to
stations were examined for the biota they held. be the most toxic and A. indica bark extract least
Diverse animal groups and some algae were found toxic. The Chi-square values of the doses of the
colonizing the sediments.The animal forms extracts showed that the data were
represented Protozoa, platyhelminthes, heterogeneous, i.e. they were insignificant at 5%
Aschehelminthes, Crustacea, Insecta. Mollusca and level. It appeared that the potentiality of the
larvae and other propagules.The station different plant extracts used in the present study
representing the dried sediments (moisture was found to be promising in different dose
12.603%) presented no adult animal forms. In levels.
such sediments only resistant cysts were found
2
amounting to 4000/m out of which 2800 were 155 RAHMAN, M.M.; ISLAM, W. &
copepod cysts and rest were the unidentified SARKER, P.K. (Institute of Biological Sciences,
ones. Station that represented semidried Rajshahi University, Rajshahi). Effect Of
conditions (moisture 40%) harboured relatively Nimbicidine On The Reproductive Potential Of
better biotic component being almost half than Cryptolestes Pusillus (Schon.) (Coleoptera:
that at wet Station (moisture 58.56%). At latter Cucujidae). Bang. J. Zool., 2006, 34 (2), 237-242.
two stations the same faunistic and floristic
components were recorded. The population was Nimbicidine® was tested against different stages
strongly correlated with the moisture content of of the life cycle of Cyrptolestes pusillus (Schon.),
the sediment in a positive manner being an insect pest of stored products. Nimbicidine
exceedingly low away from the shoreline in the significantly (P < 0.01) reduced the our position
semidried and dried sediments. rate, hatching rate, adult emergence and longevity
(male and female) of C. pusillus in various doses
154 NASIRUDDIN, M.; AZAD, M.A.; compared to control, whereas it prolonged the
CHOWDHURY, R. & SULTANA, M.N. incubation period (from 4.1 to 6.9 days) and
(Dept. of Zoology, Chittagong University, developmental time (from 44.2 to 73.3 days) at the
Chittagong). Studies On The Piscicidal same doses and in control from 3.1 to 33.3 days.
Properties Of Azadirachta Indica (A. Juss) And
Barringtonia Acutangula (Gaertn) Plant Parts On 156 RAHMAN, M.R. & JAHAN, M.S.
(Institute of Environmental Science, Rajshahi
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