Usage of the cyto-genetics and cytology to identify the action mechanisms of two bio-fertilizers on Allium cepa meristematic cells

Abstract

This study was designed to evaluate two promising bio-fertilizers: Moringa oleifera leaf extract (5.0, 10.0, 20.0%) and Sacharomyces cerevisiae aqueous extract (5.0, 10.0, 20.0%) for their safe usage on Allium cepa root meristems as a model system for monocots after 3.0 h of direct treatment. This evaluation focused on both cytogenetic and cytological levels. Cytogenetic studies screened the effect of each extract on the mitotic apparatus considering the mitotic index, mitotic phase index, percentage, and type of abnormalities. Cytological studies with transmission electronic microscope screen the effect of each extract on ultra-structural organelles (mitochondria, endoplasmic reticulum, peroxisomes, dictyosomes in addition to the vacuoles) in the cell cytoplasm. Obtained data revealed that the yeast extract shows a remarkable cytological effect on cytoplasmic organelles. By the same time, only the higher used concentration of Moringa extract shows higher chromotoxic effect on chromosomal DNA despite it shows high proliferation effect on the treated root tip cells.