——_——— ee 
SEED-EAR CHARACTERS AND PRODUCTIVENESS IN CORN 5 
TABLE 2.—The mean and extreme values for yield and for eight characters of seed 
ears and their coefficients of dispersion 
Maxi- Mini- Standard de- | Coefficient of 
Variable and unit of measure-| C.I. hoe 
ment No. mum mum ~ viation variation 
77 | 100 -£0.225| 130 ge Bee os oe a ee Be 
119| 100 + .382| 145 So To ee pena aE 
Yield__.-...-.------ per cent--) 459 | 100 225] 140 50 OT as 15d |S ce 
133 |100 + .371| 145 Dees 137.1. 068 |-. rt ee 
77| 347 + .955| 520 0 | 42.2 + .574| 122 40,171 
xa 119 | 368. 41.512] 535 220 | 43.8 + .836| 120 4 . 235 
Weight of ear___.--__- grams--') 99 | 345 + 935} 490 505. 135.3 4.597! 10.2 + .177 
133 | 226 + .788| 310 145°] 20.1 4.558 | 19 4 Eon 
77| 8.854 .015| 11.25 7.00| .629+ .009] 7.11 .097 
} 119] $844 .023| 11.25 6.25| 1699+ .013| 7.91 . 152 
Length of ear--.-...-- inches--) jo9 | g 60.016] 11.50 7.00| 1623+ .011| 7.24 . 123 
| 133 | 7.334: 014 9. 00 5.50| .5314 .010| 7.244 .140 
77| 6.81 .008 8.251 - 5.50} -.3534 .005]- 5.194 .071 
. 119} 7.084 .011 8.25 6.00| 3744 .007| 5.284 . 101 
Butt circumference-----do----)  j59 | & 974. | 008 8. 25 5.75 | 334 .006 | 4.794 . 081 
133 | 6.24 .008 7. 25 5.00} 3134+ .006] - 5.02 .097 
77|  6.19-+ .008 7.50 4.50] .3374 .005| 5.444 .074 
oe 119| 6.444 .012 7. 50 5.25| 364.007] 5.654 . 108 
Tip circumference -...-- do----/) 199 | 6, 324 | 008 7.50 5.25| 313+ .005| 4.964 . 084 
133 | 5.56 . 008 6.50 4.50| 12984 .006} 5.364 .013 
te 77. |. 49.4 910 99 23 9.86 + .134| 20.0 + . 282 
=e 119 | 58.8 + .339| 99 27 «=| 11.60 + .222| 19.7 + .405 
Weight of cob_.-.-.-_- grams-_) 99 | 4374 .233| 91 o7 9.30 + .157| 19.1 4 .345 
133 | 39.1 + .202] 71 19 7.45 + .143| 19.1 + .379 
77| 85.7 + .045| 92 76 2.20 + .030| 2.56 .035 
119| 83.8. .071| 90 75 2.36 + .045 | 2. 89-054 
Percentage of grain_.-.......-- 120! 858.054] 92 7 2.09 + .035| 2.444 _041 
133 |. 82.6 = .069| 90 72 254 + .049-| 3,07 . 059 
77| 14.7-+.033| 20 10 1.61 + .022| 10.9 4.151 
119| 166.054; 24 12 1.90 + 1036 | 11.4 + .224 
Number of rows of kernels----) j99 | 33.9 + 1034] 18 10 1.36 .023 | 10.5 + .181 
133 | 15.84 .045| 22 10 1. 67 = .032| 10.6 + . 205 
77| 46.5 + .094| 62 32 4.10 + .056| 880 .121 
119 |- 47.7 + .146| 64 34 4.34 + .083| 9.09-L .176 
Number of kernels per row----) jo | 4777 4117] 62 39 4.06 + .069| 8.51 . 146 
133 | 3834 .092| 52 28 3.40 + .065| 8 864 .171 
METHODS OF COMPUTATION 
The standard deviations and coefficients of total correlation were 
computed from correlation tables with class intervals as shown in 
Table 1. The records for each variety for the entire period were 
treated as a unit, and corrections then were made to offset the fluctua- 
tion in the means from season to season. It does not seem necessary 
to publish the 144 tables that were used. One is given for illustra- 
tion as Table 4, but it should be kept in mind that the distributions 
shown were influenced by the fluctuation from year to year as well as 
by the variation within the seasons. 
TABLE 3.—Ratios between some of the ear characters 
Ratio Cor No, C.I. No. | C. I. No. | C. I. No. 
77 | 119 120 133 
Serpe ear 4o-volnme tf ede gS el 10. 62 10. 29 10. 37 9.95 
Deca Oiuce ame Ola e bt. fe 6 Sek gS ES 1551 1. 67 1. 46 1.72 
Butt circumference to length of ear_________ mee . 769 . 801 . 810 . 851 
. Number of kernels per row to length of ear__ some 5. 25 5. 40 5. 55 5. 23 
Number of rows to butt circumference__________.__-_______---_- 2. 16 2. 34 1. 87 2. 53 
Tip circumference to butt cireumference__________-____._____--- 909 910 907 891 
1 The value used to represent volume was obtained by dividing the squared butt circumference by 4a 
~ and multiplying by the length. This assumes the ears to be equally cylindrical but should be sufficiently 
- 
- 
7 
bs, 
accurate for the present purpose. 
