Histopathologic Studies on The Effect of Some Plant Growth Regulating Substances on Albino Rats

’One hundred and four adult albino rats of both sexes were used1 males and 63 females) in 3 experiments to study the pathological ianges due to oral administration of some plant growth regulating ibstances (GRS) as Gibberellic acid (GA3), 2,4-Dichlorophen~periment 1 (GA3U Fifty rats were used in this experiment and classified into 3 groups d each group classified into subgroups. Group (1) 20 rats (4 subgroups), roup (2) 15 rats (3 subgroups) and Group (3) 15 rats (3 subgroups) lceived 20,40 and 100 ppm ofFifteen rats were used in this experiment (Group 4) and classified intosubgroups received orally 20 ppm 2,4-D for 1,2 and 3 monthsThirty rats were used in this experiment and classified into 2 groups,6) and each group of 15 rats were classified into 3 subgroups whicheived orally 1000 and 2000 ppm Alar for 1,2 and 3 months respectively .