GERMINATION OF MAIZE 



19? 



cf environment, and the ability of a strain to produce occasional 

 large ears is not necessary proof of large average yield. Un- 

 doubtedly, however, field selection has great merit, since it 

 enables the selection of the finest ears of the character desired. 

 The disadvantage of the breeding plat is that it limits the range 

 of selection to perhaps an acre of maize, while in field selection 

 twenty, forty or even 1 00 or more acres may be available from 

 which to make selections. The importance of this wider selec- 

 tion will depend upon the extent to which the finest ears under 

 ordinary field culture are due to the environment and to what 

 extent they are hereditary variations. This has not yet been 

 satisfactorily proven. Another possible disadvantage of the 

 breeding plat is that it leads to close breeding. (254) 



268. Vitality of Seed. — Owing to the time of maturity, the 

 vitality of seed is often injured by freezing before the grain is 

 thoroughly dry. It is the water that 

 freezes and thereby destroys the tis- 

 sue. The vitality may be preserv^ed 

 in two ways : first, by thorough dry- 

 ing; second, by not subjecting to a 

 low temperature. If the grain is dried 

 thoroughly, low temperature will not 

 injure it. The first method is usually 

 the most feasible. In southern lati- 

 tudes this may be accomplished by 

 storing in narrow cribs, but in more 

 northern latitudes hanging in an airy 

 place sufficiently protected from cold 

 to cause thorough drying before severe 

 weather begins, or dr^nng by means 

 of artificial heat, is desirable. The latter method is now being 

 practiced by some who make a specialty of raising seed maize. 



369. Importance of Testing Vitality of Seed. — It is very im- 

 portant, not only that seed should grow, but that it should grow 



Room for drying maize for seed 

 by artificial heat. 



