126 



The Journal of Heredity 



any other thrin the best animals he ean 

 secure with the means at his disposal. 

 Nor should any wheat farmer be 

 satisfied with anything but the best of 

 his crop for seed purposes. He shovild 

 take the greatest pains to get, first, the 

 right variety of wheat; second, well- 

 developed seed; and third, the seed 

 should be secured from the most 

 vigorous plants. The latter point is 

 ver\- important. 



WH.\T THEY ARE WORTH. 



With regard to the choice of x'unetics, 

 it may be i)ointcd out that the difference 

 in yield between two varieties of wheat 

 grown on the same farm, under precisely 

 similar soil and climatic conditions, is 

 frequently sufficient to pay the rent and 

 interest on the land on which the crop 

 was grown. This has been demon- 

 strated time and again in departincntal 

 experimental plots and on private fanns. 



Carefully-conducted experiments in 

 various parts of the world demonstrate 

 that it pays a farmer to give careful 

 attention to the selection of his seed. 



In Canada, Zavitz^ states that during 

 twelve years' work at the Ontario Agri- 

 cultural College, large, well-dcvelo]jcd 

 grain of winter varieties of wheat aver- 

 aged 46.9 bushels per acre, as against 

 39.1 bushels from small shrunken seed, 

 and with spring wheat the average 

 yield from the well-developed, plum]) 

 seed was 21.7 bushels, as again.st 16.7 

 of the small seed. 



In Britain, the University College of 

 Wales^ rcjiorts that nearly double the 

 yield was oljtained from ])him]) grain 

 as against small grain. 



Desi)rcz, in France,^ after experi- 

 menting with a large number of varieties 

 of wheat, draws the conclusion that the 

 results are marked!}' in fa\'or of large 

 seed. 



Cobb (N. S. W.),'* after an exhaustive 

 comjiarison of seed wheat from 24 

 varieties, states that the inerea.sed yield 

 obtained from well-graded seed is suffi- 

 dent to justify the installation of first 

 class cleaning machinery. 



The results obtained at some of the 

 xVinerican Ex])eriment Stations are con- 

 flicting, l)ut, where\'er care was taken 

 in the selection of seed, considerable 

 increases in yield resulted. Tliis was 

 the case at Kansas, Nebraska, North 

 Dakota, and Indiana experiment sta- 

 tions, whilst at Pennsylvania and Ohio 

 no marked increases resulted. 



From these N'arious experiments it 

 may be safely conckided that the best 

 results will be obtained by the selection 

 of well-developed, jjlmnp seed, from 

 plants of strong vitality. 



The term selection is generally more 

 restricted in meaning. It has now 

 acquired a technical significance, and 

 im]:)lies the systematic choosing of 

 s]jecific wheat-plants for future repro- 

 duction, with the object of bringing 

 about an amelioration of type. It 

 recognizes that there are endless varia- 

 tions of type in an ordinar\' wheat crop 

 — that there are grades of quality in 

 wheat just as there are grades of quality 

 in fruit and butter. 



Selection seeks to isolate those types 

 of plant which ajDproximate most nearly 

 to the ideal, and systematically to choose 

 from the produce of these types the 

 variations which are likely to be of 

 material value. 



This is the manner in which most 

 of the improvements in our field crops 

 have occurred. 



TWO KINDS OF SELECTION. 



Of course, many of the modifications 

 effected in plants, through long years of 

 cultivation, are the result of uncon- 

 scious improvement. This is exem- 

 plified by the development of the 

 cabbage, cauliflower, and kohl-rabi from 

 the woody perennial plant Brassica 

 olcracca, which is a native of Southern 

 Euro])e. The cabl)age is a modification 

 of the leaf, the cauliflower of the 

 inflorescence, and kohl-rabi of the stem 

 of this ])lant, and their origin is due to 

 long-continued selection of variations 

 which were considered desirable, and 

 not because the gardener consciously 



' Zavitz: Journal of the Hoard of Agriculture, June-, 1'>1(), p. 35. 

 « Report of University College of Wales, 1899, p. 68-70. 

 'Jour. Ajrri. Prat. (1X97). 

 "Cobh: Agricultural Gazette, New South Wales, l'M)3. 



