120 EXPEimiEXTAL FARMS 



4-5 EDWARD VII., A. 1905 



value of concentrated feed stuffs is due cliiefly to the large proportion of protein tliey 

 contain. It may safely be concluded, therefore, that the rusted straw, containing as it 

 does more than three times the protein found in the rust-free straw, is very much 

 superior in fading value. 



Further, in the rusted straw we have a slightly higher percentage of fat — the 

 constituent next in value to protein — and somewhat less fibre — the element of least 

 value in a fodder, and hence there is additional evidence of the most satisfactory 

 character to support the statement respecting the more nutritious nature of the rust- 

 affected straw. 



The Grain. — The small and shrivelled character of the grain from the rusted wheat 

 may be deduced from the data in the first column of the table — the weight of 100 

 kernels being only half that of 100 kernels from the unaffected wheat. This fact, 

 however, from the standpoint of a feed does not betoken a lessening of the nutritive 

 qualities; indeed, as the data for the protein show, it has, weight for weight, consider- 

 ably the higher value. 



The protein of the shrivelled grain is 3 "19 per cent higher than that of the plump 

 grain from the rust-free plant. Part of this higher prot-ein content in the smaller 

 grain is no doubt to be accounted for in its larger proportion of bran — but chiefly is 

 it due to the fact that the transference and accumulation of starch in the kernel has 

 been but partial and incomplete. ^ 



Other features of note in the analysis of the grain from the rusted wheat are : 



(1) the somewhat larger percentages of fibre and ash — indicating more bran — and, 



(2) the lower carbo-hydrates (starch) and fat content. 



Apart from the valuable information that the^e data furnish regarding the relative 

 feeding value of the straw and grain of rusted wheat, we have in these results interest- 

 ing evidence as to the physiological effect of the rust on the wheat plant. Speaking 

 broadly, there are (after germination) two periods in the life of the wheat plant— the 

 first, a period of feeding and assimilation; the second, a later and usually shorter period, 

 during which the food materials accumulated in the stem and leaf (straw) are trans- 

 ferred to and stored in the seed (kernel). There is, of course, no exact time when it 

 can be said that the one ends and the other begins. Under normal conditions there is 

 a gradual cessation of feeding, both by root and leaf, accompanied by an ever increas- 

 ing movement of the accumulated material to the seed. The first period is charac- 

 terized by growth, the second is recognized by the maturation or ripening of the seed. 



Further, it would seem that in the development of the seed, the albuminoids or 

 protein are the first to be transferred and later — towards the close of the maturation 

 period — the carbo-hydrates (starch, &c.), are more particularly deposited. 



The rust apparently does not affect the vitality of the wheat plant during the first 

 stage or period, but as the season progresses and the ripening period advances the 

 fungus attains the ascendancy, crippling the energies and functions of the tissues and 

 checking the movement of the food materials to the seed. In other words, the growth 

 of the rust arrests development and induces premature ripening, which, as we have 

 seen, means a straw in which still remains the elaborated food, and a grain small, 

 slirivelled, immature, rich in protein and deficient in starch. 



It may be well to point out that although the rust makes the grain more nitro- 

 genous, it at the same time very materially reduces the yield per acre — the present 

 figures indicating a loss in weight of about 50 per cent. 



We have not as yet been able to complete the analysis of the milling products of 

 this shrivelled wheat, but we may rest assurer! until such time as the data are avail- 



* Note.— Some years ago in determining the relative feeding value of frosted wheat 

 (which presents a shrivelled appearance very similar to that of the grain from rusted 

 wheat) we found that the protein content was considerably higher than in the unfrozen mature 

 grain. It is evident that the effect of rust and frost in this respect, is the same, resulting in 

 a premature ripening or rather a drying out of the grain which, as we have seen, means a 

 kernel high in protein, but low in starch. 



