THE LOW TEMPERATURE PROMOTION OF FLOWERING 49 



he was unaware of the additional requirement for long-days in his 

 species. Following the First World War there was considerable activity 

 in Russia, and names such as Murinov, Maximov, Pojarkova, and 

 Lysenko (or Lyssenko) appear in the literature. T. D. Lysenko's 

 name is commonly associated closely with the early work on vernali- 

 zation. His first paper appeared in 1928. Compared to the discoveries 

 of many other workers, his contribution was probably rather slight 

 (his finding that vernalized seed could be dried out and stored without 

 losing the vernalized condition is most frequently mentioned), but 

 he contributed the term Jarovization (1929) and he developed a 

 theory, that of Phasic or Stadial Development, which has had a 

 profound influence on Russian botany ever since. His departure 

 from Klebs' clear insight, in that he thought the genetic material 

 itself was influenced by the environment, is interesting in that it led 

 to widespread political involvement in scientific research in the 

 USSR (see section on theory below). 



In Utrecht, Holland, A. H. Blaauw directed an active research 

 laboratory concerned with flowering response of 23 "bulbous" and 

 nine other horticultural plants, primarily as their flowering is influenced 

 by temperature. Blaauw began the work in 1918 continuing until 

 his death in 1942, and his laboratory is still very active. Blaauw's 

 work is especially interesting because he used carefully controlled 

 conditions long before our environmental chambers and phytotrons 

 (see Chapter 5) were known. He was able to do this, because bulbs 

 do not require light during the temperature treatment, and accurate 

 control of temperature was even then technically quite feasible. 



Beginning with the 1930's, an historical summary becomes difficult, 

 because work was being carried out at many laboratories around the 

 world. Nevertheless, the contributions of two laboratories are 

 especially outstanding: G. Melchers and Anton Lang in Berlin- 

 Dahlem and later Tubingen, Germany, and F. G. Gregory and O. N. 

 Purvis in Imperial College, London. Any summary of current 

 vernalization theory must rely heavily upon the work emanating from 

 these laboratories. More recently, P. Chouard at the Sorbonne in 

 Paris has studied many diff*erent plants and their responses to cold, 

 as have workers such as S. J. Wellensiek, K. Verkerk, and others in 

 Holland. W. W. Schwabe in England has pioneered work on short- 

 day Chrysanthemums y and Klaus Napp-Zinn in Germany has 

 developed a rather complex theory with Arabidopsis thalinna. Of 



