100 



IMPROVING THE QUALITY OF WHEAT. 



TABLE 28. Analyses showing transmission of kernel weight. 



Table 28 shows the analyses of plants raised in 1902 and their prog- 

 eny raised in 1903, arranged according to weight of average kernel. 

 There is more variation in this table than in the preceding one, but 

 the tendency toward transmission of proteid nitrogen in the average 

 kernel may be noted. The averages for 1902 are much higher than 

 for 1903, owing partly to the higher percentage and partly to greater 

 kernel weight. 



The weight of the average kernel shows some tendency toward 

 transmission, although there are some variations. It will be noticed 

 that the kernels average much heavier in 1902 than in 1903, and that 

 in spite of this the percentage of proteid nitrogen is higher in 1902. 

 The relation of light kernel and high percentage of nitrogen does not 

 therefore appear to hold as between crops of different years. 



All of the qualities of which determinations have been made in 

 both years appear to be transmitted. It may be safely assumed that 

 certain plants will have greater power to transmit these qualities than 

 will the average plant. Such plants will assert themselves in the 

 course of three or four generations. From these plants individuals 

 may be selected that have a combination of the desired qualities. 



YIELD OF GRAIN AS AFFECTED BY SUSCEPTIBILITY TO COLD. 



As has already been stated, a large number of plants on the breed- 

 ing plots were killed during the winter of 1902-3. This afforded an 

 opportunity to ascertain the effect of the severe weather upon the 

 surviving plants. The question arose whether the surviving plants of 

 a family of which a large percentage of members were killed yielded 

 less per plant than the plants of a family of which but a small per- 

 centage had succumbed. As each spike of the crop of 1902 was 

 represented by a number of plants, and as records of each plant 

 were available, there were very extensive data at hand from which 

 to secure information on the subject. 



In Table 29 the surviving plants of each immediate family, or, in 

 other words, the surviving plants descended from the same plant of 

 the previous year, are classified according to the percentage of plants 

 that survived the winter. Thus all plants of which only from 10 to 20 



