Mar. 8, 1924 
Acidity Changes during the Growth of Wheat 
729 
figures 1 to 3, inclusive. Figure 4 shows such a curve illustrating the 
acidity changes occurring in Kanred wheat sown on January 5, 1923, in a 
greenhouse which was too warm for winter wheat to grow normally. 
The plants were fairly vigorous in the early-seedling stage, but they were 
only 4 inches tall at the age of 10 weeks, 8 inches at the age of 13 weeks, 
and 9 inches at 15 weeks, at which time growth had almost ceased. The 
leaves remained turgid and green but very narrow, and the stems were 
very spindling, with almost no tillers. No sign of heading had appeared. 
Fig. 4. —The titratable acidity (and Ph values in parentheses) of juice of unhealthy Kanred wheat from 
the seedling stage to cessation of growth, with some corresponding measurements on Khaoli and Tittle 
Club growing alongside. (Greenhouse, Jan. 5 to Apr. 20, 1923.) 
Seed of Little Club and Khapli emmer had been sown at the same time 
in the same bench. Khapli was flowering at the age of 15 weeks and the 
acidity measurements, made during the early-seedling, late-seedling, 
and flowering stages, respectively (fig. 4), were normal values for these 
stages of growth. Little Club, however, became badly infected with 
mildew, so that it never headed. By the age of 15 weeks its vigor was 
visibly affected by the disease, and its unhealthy condition was reflected 
in the abnormally high acid concentration for that stage of development. 
The acidity of Kanred in this environment was very high compared to 
that of the spring varieties at the corresponding periods. The curve 
differs from those of the spring wheats in the very slight drop during the 
