الفهرس Only 14 pages are availabe for public view
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Abstract
The chemical pesticides are used, nowadays, on a large scale to protect crops against pests. Pests cause annually a drastic loss of the economical crops allover the world. The wide production and uses of chemical pesticides causes a serious pollution to the surrounding environment.
Man today is concerned very much with the pollution of his environment. Biological control agents for plant disease are currently being examined as alternative to synthetic pesticides due to their perceived increased level of safety and minimal environmental impacts.
The present investigation was planned to compare the mutagenic effects of two chemical fungicides (mancozeb and nimrode) with the two biological fungicides (plant guard and rhizo-N). In addition, effect of these pesticides on polyacrylamide gel electrophoresis profiles of Allium cepa seed proteins, and the different parameter of the cell cycle were investigated.
At the cytological level, the four fungicides used in this study induced a decrease in the mitotic index accompanied with considerable percentage of chromosomal abnormalities. These abnormalities include stickiness, C-metaphase, disturbed chromosomes at metaphase and anaphase, bridges, laggards and trimultipolar cells. True clastogenic abnormalities including chromosome bridges and micronuclei were observed after treatment with the fungicide mancozeb and plant guard.
Image cytometric measurements of mitotic cell cycle showed accumulation of cells in the G2 phase in roots treated with the fungicide mancozeb, while the cells accumulated at G1 phase in roots treated with the biofungicide plant guard. On the other hand, the four fungicides caused changes in the protein-banding pattern. These changes include the absence of some bands and the appearance of few novel bands as well as overexpression of the others. The results showed that the chemical fungicides mancozeb and nimrod have more mutagenic potentialities than the biological fungicides.