Abstract
The effects of the insecticide O-(4-bromo-2, 5-dichloro-phenyl) O-methyl phenyithiophosphonate “Phosvel” on the meiosis and pollen viability of Vicia faba were studied. The plants were sprayed at the seedling and flowering stages with two concentrations of the insecticidal solution which are usually used in the field in Egypt (2.25 L. of “Phosvel” solution “active ingredient 30%” were mixed with 200 L. water for the first concentration, and with 500 L. water for the second one). Most of the treatments affected a significant percentage of abnormal pollen mother cells. The induced meiotic irregularities were: disturbed 2 nd meta- and anaphases, stickiness, lagging chromosomes, fragments, anaphase bridges, univalents in diakinesis, micronuclei in the 1st and 2 nd telophases tages and multipolar telophase II. “Phosvel” did not show significant effect neither on tetrads nor on pollen viability.
