National Research Centre for Weed Science, Maharajpur, Adhartal, Jabalpur-482 004
Treatment of onion seeds, tissues and enzymatically isolated protoplasts with 1–275 parts/10−6 solutions of commercial preparations of alachlor and 2,4-D for different durations resulted in different degree of toxicity leading to inhibition of germination and root and shoot growth of seedlings and cell death. The study of viability of cells as revealed by microscopic observations of cyclosis, plasmolysis and vital staining assay with methylene blue and fluorescinediacetate revealed that the cells were relatively more tolerant to alachlor than 2,4-D, The toxic effect of herbicides caused coagulation of cytoplasm, nuclear and nucleolar swelling and bursting and rupture of the plasma membrane and tonoplast.
