LITERATURE REVIEW 

 Gibberellic Acid 



History 



Gibberell ins are defined by Phinney and West (1961) as substances 

 possessing the same or similar carbon skeleton as gibberellic acid (GA 3 ) 

 and that are biologically active in stimulating cell division, cell 

 elongation, or both in plants. The earliest known description of the 

 effects of gibberell ins was in 1809 by Konishi, a semi -literate Japanese 

 rice farmer, who described rice plants which grew excessively tall 

 (Stowe and Yamaki, 1957). The diseased plants could not support them- 

 selves and eventually died due to parasitic action (Yabuta, 1935; 

 Salisbury and Ross, 1978). Salisbury and Ross (1978) indicate that as 

 early as the 1890' s the Japanese were referring to these symptoms as the 

 "bakanae" ("foolish seedling") disease. The disease was determined to 

 be caused by a fungus, Gibberella fujikuroi (sexual stage) and Fusarium 

 moniliforme (asexual stage). The active compound was isolated and iden- 

 tified in the 1930' s by Yabuta and Hayashi , Japanese pathologists, who 

 named it gibberellin (Yabuta, 1935; Stowe and Yamaki, 1957; and Russell, 

 1974). Japanese scientists were interested in the pathological aspects 

 of gibberell ins rather than physiological impacts (Salisbury and Ross, 

 1978). Thus, even though the first gibberellins were isolated in the 

 1930' s, Western scientists did not become interested in the physiologi- 

 cal effects of gibberellins until the early 1950' s due to (1) the 



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