16 

 Shininger (1974) reported gibberellin caused cell elongation in 9 of 

 21 species tested and both cell elongation and increased cell division 

 in 4 of the 21 species. The physiological mode of action for cellular 

 elongation results from numerous inter-related processes; however, the 

 sequence in which these processes occur remains uncertain. Gibberellins 

 have been shown to increase hydrolysis of starches, fructosans, and 

 sucrose molecules (Paleg, 1965; Audus, 1972; Kaufman, 1974; Salisbury 

 and Ross, 1978). Paleg (1960) demonstrated an increase in a-amylase 

 content of barley endosperm treated with gibberellic acid. Chen and 

 Park (1973) also demonstrated gibberellic acid enhanced amylase syn- 

 thesis and reported enhanced synthesis of proteins and RNA in Avena 

 fatua seeds. Weaver (1972) cited studies which attributed increased 

 enzyme activity to increased synthesis; however, Kaufman (1974) attri- 

 buted increased enzyme activity in barley aleurone to increased release 

 of enzymes rather than increased synthesis. Cleland et al . (1968) 

 reported increased levels of activity of cell wall hydrolases in Avena , 

 i.e., cellulase, hemicellulase, and pectinase, which has been shown to 

 result in increased plastic extensibility of the cell wall within one 

 hour after treatment with gibberellic acid (Adams et al . , 1973; Montague 

 et al . , 1973). The above conditions have been shown to result in 

 changes in osmotic potential at the cellular as well as whole plant 

 level. Ende and Koornneef (1960) reported a higher osmotic potential in 

 tomato plants; however, Castro (1976, cited in Castro and Rossetto, 

 1979) reported lower osmotic potential in tomatoes treated with gib- 

 berellic acid. Other plants in which lower osmotic potentials have 

 resulted from gibberellin treatment include lettuce (Stuart and Jones, 

 1977), sunflower (de la Guardia and Ben! lock, 1980), cucumber (Katsumi, 



