Oct. 1,1920 Fusarium-Blight (Scab) of Wheat and Other Cereals 31 



variety in both series. While this seems possible, it does not seem 

 probable in this case. The plots were small and only 2 feet apart, so 

 that if some plots were more heavily infected because of the more heavily 

 infected seed sown on them the inoculum from them could easily have 

 served for the plants in the neighboring plots only 2 feet away. The 

 plot with the variety Preston X Kubanka cross (Wisconsin 101), which 

 had 22 blighted heads, was between plots that had only 1 and 3 blighted 

 heads, respectively. 



Table II. — Averages of actual counts of blighted wheat heads in two series of different 

 varieties, arranged according to degree of infection 



Variety. 



Preston X Kubanka cross 



Red Fife 



Red Fife selection E. G. D. 9171. .. 



Marquis 



Marquis selection 



Pedigree Marquis 



Red Fife selection 



Fife, Minn. 163 



Spring Velvet Chaff 



Haynes Bluestem X Kubanka cross 



Spring- wheat selection 



Bluestem 



Bluestem 



Spring- wheat selection 



The differences between varieties in susceptibility to blight was brought 

 out more plainly in a field where two spring-wheat varieties, Marquis and 

 durum, were sown side by side on the same piece of land, following 

 corn. The infection of the Marquis wheat where the plants were standing 

 was less than 1 per cent and from 10 to 15 per cent among the lodged 

 plants, while the infection among the standing durum plants was from 9 

 to 10 per cent and as high as 100 per cent among the lodged plants. 



Throughout the field there were numerous cornstalks with perithecia 

 containing viable spores of Gibberella sdubinetii and other parasitic species 

 of Gibberella, as well as numerous viable conidia of several blight-causing 

 Fusarium species. While we can doubt the result obtained with various 

 varieties on the University plots, the results obtained on this field indicate 

 clearly the existence of a difference in varietal susceptibility to head- 

 blight. Further observations and experiments in this direction will, no 

 doubt, be of great importance. 



LITERATURE CITED 

 (]t) Bolley, H. L. 



1913. wheat: soil troubles and seed deterioration; causes of soil 

 sickness in wheat lands; possible methods of control; crop- 

 PING methods with wheat. N. Dak. Agr. Exp. Sta. Bui. 107, 96 p. 

 45 fi g- 



