398 



MG 



PLANT GROWTH SUBSTANCES 



1 



T 



T 



T 



2,4-DICHLOROPHENOXYACETlC ACID SUNr LUWLK 



^>^BETA-NAPHTHOXYACETIC ACIO 

 '^r-S^ =;^-°"^J^>.<^ 



600 



IN0OLE-3-ACETIC ACID 



>4LPHA-NAPHTHALENEACETIC ACiO 



400 



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y 





'O 







CYSTEINE HYDROCHLORIDE 



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o 



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UJ 



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li. 

 o 



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INOOLEBUTYRIC ACID 



O 

 liJ 



I- 

 UJ 



200, 



< 

 a: 



UJ 



100 



_.,^-— O0.BETA-NAPHTHOXYACETIC ACID Tr\Q^nnr\ 

 0— -^ '^ /- TOBACCO 



" " ^ " ° ^V 



"^ CL X.INDOL 



24-OICHLOROPHENOXYACETIC ACID 



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INOOLEBUTYRIC ACIO 



INDOLE-3 -ACETIC 

 ACID 



IX 10 



13 



I 



I X 10'' 



IX 10" 



IX 10 



GROWTH -REGULATING SUBSTANCE (G. PER LITER) 



Figure I. Average wet weights in milligrams of sunflower and tobacco 

 tissue cultures incubated in the dark for six weeks on basal, synthetic media 

 supplemented with different concentrations, respectively, of growth-regulating 

 substances as indicated. Zero concentration indicates the control cultures with 

 no added growth-regulating substance. Each point represents the average 

 wet weight of 36 to 108 tissue pieces from one to three experiments. 



