422 



MAIZE 



MAIZE 



This part is poor in both protein and oil, consisting 

 mainly of starch. (Pig. 644.) 



(3) The germ itself, which occupies the central 

 part of the kernel toward the tip end. This is very 

 rich in oil. More than four-fifths of the entire oil 

 of the kernel resides in the germ. It is also rich 



Fig. 645. Kernels. On the left, high-oil kernels (large germs) ; 

 on the right, low-oil kernels (small germs). 



in protein, containing nearly one-fifth of all the 

 protein in the kernel, although the germ itself 

 constitutes only about one-tenth of the weight of 

 the kernel. (Pig. 645.) 



In selecting seed corn by mechanical examination 

 for improvement in composition, we remove from 

 the ear a few average kernels, cut them into cross- 

 sections, preferably near the tip end of the kernel 

 (see longitudinal sections), and examine these sec- 

 tions as they are cut, usually simply with the naked 

 eye, selecting for seed those ears the kernels of 

 which show the qualities desired. 



Samples for analysis. 



In order that the breeder may know what he has 

 accomplished in his work of mechanical selection, 

 he should have an analysis made of two composite 

 samples representing each of the two lots of ears ; 

 that is, the selected lot and the rejected lot. One 

 composite sample should be made by taking ten 

 average kernels from each of the selected ears 

 (ninety-six ears preferred) and another sample by 

 taking ten average kernels from each of the rejected 



ears (100 ears or more). Each of these two samples 

 should be put into a separate sack, properly labeled, 

 and sent to the chemist for analysis. Of course, 

 if the breeder desires to breed for physical type 

 and increased yield only, then no chemical analysis 

 is needed, and all that is necessary to begin work 

 is to select the ninety-six most nearly perfect ears 

 obtainable for the breeding plot. 



Size of breeding plot. 



The best number of ears to use in a breeding 

 plot is as yet an unsettled question. There are 

 several conflicting factors entering into the con- 

 sideration. On the one hand, the smaller the num- 

 ber of ears, the choicer can be the selection of the 

 seed ; while on the other hand, the larger the num- 

 ber of breeding rows, the better can be the selec- 

 tion of seed for the next crop. Then, again, there 

 is undoubtedly some danger of evil effects from 

 too close inbreeding by the use of too small a 

 number of ears. From our present knowledge, how- 

 ever, we think that ninety-six ears is a safe num- 

 ber to use, so far as inbreeding is concerned, and 

 this is the number that we suggest in these direc- 

 tions, it being understood that alternate rows are 

 to be detasseled and all seed corn selected from 

 detasseled rows. 



Planting by the row system. 



The ninety-six selected seed ears are planted in 

 ninety-six separate rows. These rows should be at 

 least one hundred hills long, but they may well be 

 forty rods long, as the quantity of seed will usually 

 permit this. It is recommended that these ninety- 

 six seed ears be numbered ' from 1 to 48 and from 

 51 to 98, the numbers 49 and 50 being omitted ; 

 also, that ears 1 to 48 be planted in one-half of the 

 plot and ears 51 to 98 in the other half, preferably 

 end-to-end with the first half, leaving one hill un- 

 planted to mark the line between the halves, and 

 also leaving one row unplanted to mark the line 

 between rows 24 and 25 and between rows 74 and 

 75, that is, between quarters. In this way, row 51 

 (planted with seed from ear 51) is a continuation 

 of row 1 (planted with seed from ear 1), and the 

 two rows may well extend eighty rods across a 

 forty-acre field. The breeding plot can be planted 

 with a corn-planter, although it will require some 

 time and patience, and if the planter is an edgedrop 

 it vfill be necessary to put a suitable cone or 

 inverted funnel in each seed box to keep the small 

 quantity of corn to the outside. Place the shelled 

 corn from ear No. 1 in one box and from ear No. 2 

 in the other ; drive to the middle of the plot, thus 

 planting rows 1 and 2 ; clean out the boxes ; move 

 forward one hill ; put in the corn from ears 51 and 

 52 ; use the foot-trip till the corn begins to drop ; 

 then drive on and plant rows 51 and 52. Turn at 

 the end ; clean out the seed ooxes ; put m ears 53 

 and 54 ; plant back to the middle ; clean out, put 

 in ears 3 and 4j and then plant on back to the 

 beginning line, thus continuing until the breeding 



' These numbers would be 101 to 148 and 151 to 198 

 the first year, 201 to 248 and 251 to 298 the second year, 

 etc. [See under Register number, page 425.] 



