Question

why were pour plates rather than spread plates used to determine the evidence of antibiosis?

Answer 1

  In the pour plate the bacterial inoculums is mixed with the agar and poured in the medium. After incubation we can get a variety of microbes which ranging from micro aerophilic growing deep in the medium and aerobic organism that grow on top of agar medium. If antibiosis is seen by of the organism we can easily detect it as there is less contamination due to growth of microbes in between the organisms while in spread plate we may not ascertain the growth inhibition of microbes is by antibiotic activity or by contamination by fungi which are aerobic in pour plat as microbes grow deep in media only antibiosis activity can stopped the growth of other microbes but not fungi. Thus pour plate give accurate results of antibiosis while spread plate may give false result due to growth of other contaminants. As the in pour plate the microbes grow in deep layers there is less chance of contamination compared to spread plate.