May 8, 1916 



Occurrence of Sterile Spikelets in Wheat 



247 



Table IX. — Correlation between the percentage of sterile spiklets per plant and the 

 average length of culm in wheat ^ 



' r=— o.4482±o.03i6. 



CORRELATION BETWEEN THE PERCENTAGE OE STERILE SPIKELETS AND THE 

 LENGTH OF SPIKE PER PLANT 



The average length of spike per plant was determined by dividing 

 the sum of the lengths of the spikes per plant by the number of spikes. 

 The calculations were expressed in centimeters. The coefficient of 

 correlation between these two characters is —0.451 ±0.031 (see Table X). 

 Since the longest spikes usually occupy the longest culms, we should 

 expect the same relationship between the length of spike and percentage 

 of sterile spikelets as was found between the latter character and the 

 length of culm (see Table IX). There is a very close relation, the 

 coefficient of correlation with the culm being 0.448 ±0.031, a difference of 

 0.003 between the two coefficients. 



Table X. — Correlation between the percentage of sterile spikelets per plant and the 

 average length of spike in wheat ^ 



r=-o.45i5±o.03io. 



