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Effect of
Zn(II) deposition in soil on mulberry-silk worm food chain
Muhammad Ashfaq1, Wakeel
Afzal1 and Muhammad Asif Hanif2*
1Department
of Agriculture Entomology, University of Agriculture,
Faisalabad-38040, Pakistan.
2Department
of Chemistry and Biochemistry, University of Agriculture,
Faisalabad-38040, Pakistan.
*Corresponding author. E-mail:
muhammadasifhanif@ymail.com. Tel: +92333836278. Fax:
+92419201085.
Accepted 30 December, 2009 |
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The present study was conducted to evaluate the entrance of
Zn(II) into the food chain of Bombyx mori (silk worm)
from mulberry plants irrigated using Zn(II) containing
synthetic effluents. The soil, plant, silkworm and their
excreta were sampled to determine Zn(II) amount by using
atomic absorption spectrometry (AAS). The amount of Zn(II)
deposited by synthetic effluent to soil was increased with
pH of the effluent. However, the bioaccumaltion of Zn(II) in
Morus alba leaves and B. mori larvae was high
when the effluent pH was in the acidic range. B. mori
excreted considerable amount of Zn(II) but still most of
Zn(II) resided inside its body. The maximum Zn(II) amount
detected in soil, leaves, larvae and faeces were 386.51 ±
0.03, 142.85 ± 0.001, 91.375 ± 0.019 and 42.13 ± 0.69 mg/kg,
respectively. Zn(II) present in B. mori body was
responsible for toxic effects on its life cycle. First
instar of B. mori was most affected by Zn(II)
toxicity. Body length, body weight of B. mori
decreased with increase in bioaccumlated Zn(II) amount in
larval body. Higher Zn(II) concentration in larval body
increased B. mori death rate significantly.
Key words:
Bombyx mori,
Morus alba, Zn(II), food chain, bioaccumulation. |
