A BRACHYTIC VARIATION IN MAIZE. 



11 



ear stalk. This factor is the number of nodes. The actual number 

 of nodes can not be determined with accuracy, and an estimate is 

 likely to give very misleading results. 



Further evidence for the independent inheritance of the brachysm 

 of ear stalks and that of the culm is to be found in an analysis of 

 the correlations of these characters. 



In the normal plants of the second generation of the brachytic- 

 Boone hybrid there was a correlation of 0.295 ±0.06 between the 

 length of the longest internode on the main culm and the length of 

 the ear stalk. This correlation is reversed in the brachytic plants of 

 the same hybrid, but the coefficient of 0.09 ±0.09 is not a significant 

 deviation from no correlation. These low correlations indicate an 



28 cm 



Fig. 4. — Frequency distribution of length of ear stalk on brachytic, brachytic X Boone Fi, 

 and brachytic and normal plants segregated in the F s of brachytic X Boone. 



almost complete independence of the factors which affect the inter- 

 node length of the culm and those which affect the ear stalk. 



AGRICULTURAL ADVANTAGES. 



Brachysm in maize produces a form of plant which seems admir- 

 ably adapted to meet the unusual requirements of dry land and 

 irrigated regions. The chief obstacles to the utilization of such 

 variations lies in the numerous defects which commonly accompany 

 them (Cook, 4) , but the present brachytic strain is relatively free from 

 undesirable corollaries. 



The striking characteristics of this brachytic type of plant are its 

 reduced height and sturdy erectness. There are many situations in 



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