406 GROWTH FACTORS AND FLOWERING 



percent indoleacetic acid substituted for the excised axillaries signifi- 

 cantly slows flowering again, but it has no effect on the compensatory 

 growth. 



The much greater growth of the leaves on the main shoot did not 

 completely compensate for the loss of all leaves on the many axillary 

 shoots — total leaf weight was 60% of that in the intact controls. 



The small leaves of the apical bud showed greater compensatory 

 growth when older leaves were present. lAA could not substitute for 

 the older leaves in this effect. 



The clone of Coleiis blumei used in these experiments was ap- 

 parently day neutral with respect to flowering: weeks of exposure to 

 short-day and long-day conditions had no significant effect on speed 

 of flowering. Long-day treatments given by extending the normal day 

 gave equivalent results for flowering to those obtained by interrupting 

 the night. But the compensatory growth induced by excising all 

 axillary shoots was reduced by interrupted nights when compared to 

 extended-day treatments. 



REFERENCES 



Addis, T., and W. Lew. 1940. The restoration of lost organ tissue. The rate and 



degree of restoration. J. Exptl. Med., 71, 325-33. 

 Arthur, J. M., J. D. Guthrie, and J. M. Newell. 1930. Some effects of artificial 



climates on the growth and chemical composition of plants. Am. J. Botany, 



17, 416-82. 

 Audus, L. J. 1953. Plant Growth Substances. Interscience, New York. 

 Bonner, J., and J. Liverman. 1952. Hormonal control of flower initiation. 



Growth and Differentiation in Plants, W. E. Loomis, Editor. Iowa State 



College Press, Ames. Pp. 283-303. 

 Ebert, J. D. 1954. Some aspects of protein biosynthesis in development. Aspects 



of Synthesis and Order in Growth, Dorothea Rudnick, Editor. Princeton Uni- 

 versity Press, Princeton, N. J. Chapter IV. 

 Garner, W. W., and H. A. Allard. 1931. Effect of abnormally long and short 



alternations of light and darkness on growth and development of plants. 



/. Agr. Research, 42, 629-51. 

 Highkin, H. R., and J. B. Hanson. 1954. Possible interaction between light-dark 



cycles and endogenous daily rhythms on the growth of tomato plants. Plant 



Physiol, 29, 30f-302. 

 Hillman, W. S., 1956. Injury of tomato plants by continuous light and unfavor- 

 able photoperiodic cycles. Am. J. Botany, 43, 89-96. 

 Jacobs, W. P. 1950a. Auxin-transport in the hypocotyl of Phaseolus vulgaris L. 



Am. J. Botany, 37, 248-54. 



