EFFECTS OF ELECTROMAGNETIC FIELDS (CREATED BY HIGH-TENSION LINES) ON SOME INDIGENOUS PLANT SPECIES IN THE VICINITY OF KARACHI-II. ASTERACEAE

To study the effects of electromagnetic fields of high-tension lines on plants, 13 specimens belonging to 10 species of family Asteraceae were collected from different localities in and around Karachi under high-tension lines of 132 kV. In addition same species were also collected as control from areas free from electromagnetic fields. The test and control specimens were studied for meiosis in pollen mother cells (PMCs), meiotic products and pollen fertility. A marked difference in meiotic abnormalities and magnetic field strength was observed in control and test specimens and localities. PMC meiosis showed certain abnormalities which included stickiness, precocity, laggards, bridges, multipolar divisions etc. The difference between the meiotic abnormalities of test and control specimens was found to be statistically significant. Microspore diads, triads and hypertetrads were observed besides normal microspore tetrads. The pollen fertility also decreased in test specimens; and the difference between test and control specimens was found to be significant.