100 



BOTAX/CAL GAZETTE 



[FEBRUARY 



occurs in Uruguay. He notes, however, that the culm habit in 

 Uruguayan oats and rye germinated at high temperatures is dis- 

 tinctly recumbent, whereas it is upright from the beginning in the 

 case of plants grown from seeds germinated at low temperatures, 

 he low temperature plants begin the formation of the culm (shoot- 

 ing) much earlier than do the high temperature plants. A typical 

 experiment with oats is outlined as follows: 



I late iif seeding 



Temperature during 

 germination 



January 18 January 18-23, 6-9 ; 



January 23-25, 25 

 January 18 January 18-20, 25°; 



January 20-25, 6-9 



Date of transfer 

 into field 



January 25 

 January 23 



Beginning shooting 



March 15 



No shoot formation on 

 April 25, shooting not 

 expected before 

 October 



In another series it was found that even 24 hours of exposure 

 to a germination temperature of 25 led to the same abnormal 

 course of development as indicated in the second series here quoted. 



Gassner and Grimme (4) have made one attempt to correlate 

 the effects of germination temperatures and the resistance of cereals 

 to frost injury. They analyzed the first leaves of winter and spring 

 rye germinated at 5-6 C. and at 28 . They found that the seed- 

 lings germinated at the lower temperature had a higher sugar con- 

 tent than seedlings germinated at the high temperature; moreover, 

 seedlings of a hardy winter rye had a higher sugar content than 

 those of a spring rye grown under the same conditions. Their 

 results with rye are shown in table I. 



Hutcheson and Quantz (7) conducted experiments on the effect 

 of greenhouse temperatures on the growth of the small grains: 

 wheat, oats, barley, and rye. All four crops were grown under four 

 temperature conditions, namely, i4.4°C, 16. 6° C., i8.3°C, and 

 23. 9 C. The higher temperature range had a distinctly detri- 

 mental effect upon the growth of the barley and a less harmful 

 effect upon the growth of wheat and rye, while oats had a normal 

 course of development at all the temperatures used, although the 

 oal culms were weaker at the higher temperatures. The high 



