الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
The present experiments were carried OL.~ to study the genetic effects of Ismadye raw waste effluent on Drosophila melanogaster and to compare these effects with those induced by the same waste after special physical and chemical treatments. The experiments were designed to estimate the changes in some components of fitness, sex linked recessive lethals and chromosomal aberrations. Tho fl ies of ~ m~l anoqa,ster were reared on meaUa containing different samples of raw and treated waste effluent for fiv~ successive generations. In each treated generation of the flies, body size, development’ time and percentage of amergance were recorded for flies reared on media containing four different raw waste samples namely R1’ R2’ R3 and R4 in addition to their respective treated samples namely TR1’ TR2’ TR3 and TR4. At the first and fifth generations of exposure, sex~linked recessive lethal mutations and chromosomal aberrations were investigated for the flies reared on media containing the two raw samples R2 and R4 and their respective treated waste TR2 and TR4 samples. Sex-linked recessive lethals were tested using Muller-5 technique. Chromosomal aberrations were investigated with respect to the quantitative and qualitative changes in chromosomal gene arrangements. For each treatment, salivary gland chromosomes of the third instar larvae were cytologically examined for chromosomal gene arragne¬ ments they contain. The results obtained from these experiments can be 8ummarized as followes: 1- Rearing larvae on media containing raw waste samples had an obvious effect on reducing body size below the control level. The reduction in,body size varied from one sampl e-; to another. After five generations of treatmentJ body size slightly declined by ~out 3 in samples treated by R4 raw waste. The other three samples Ri’ R2 and R3 had a significant effect on reducing body size by about 7, 13 and 24respectively. The treated waste had no significant effect on reducing body size, below the control level. 2- Treating the first generation by the raw waste led to 8 significant reduction in development.~ime, while the following developm$ntaltime up to the fifth generation, weB almost equal to the control population~ Rearing larvae on media containing treated wastes led to a slight decline in the duration of growth period below the control level. 3- The raw samples had also a significant~effect on redu~ng the percentage of emergence. In some raw samples the percantage ,survival declined by about 40 to 50 below the control level. The treated wastes had lower effect when compared with the raw ones. In some treated w8ste ~amples, the viability declined by about 25-30 for the first two generations after which it tended to increase towards the control level. In other samples, the changes in the viability during the. five generations of the exposure were very small. 4- The raw waste had a mutagenic effect with respect to the induction of sex-linked recessive lethal mutations. After one generation, percentage of lethality significantly increased in the treated than in the contr01 population. At the fifth generation, the percentage of sex-linked recessive lethals did not significantly deviate from the control level. , 5- The raw waste had an obvious effect on producing quantitative and qualitative changes in chromosomal gene arrangements. Considerable changes in the frequencies of different chromosomal inversion presented in the contrQl population were observed. Moreover, six new induced inversions designated (2L) AS1’ (2L) A~2. (2L)AS3’ (2R)AS1’, (3L) AS1’ in the treated populatiGn. (3L)AS2 were detected 6- The treated waste had no much effect either on genic or on chromosomal levels. The frequencies ef sex linked recessive lethals were’nealy equal to the control; besides, no effect on chromosomal structure could be detected. 7- The results revealed the possible genetic hazards caused by releasing some industrial wastes, without chemical treatment, in the environment.