/

/!

_

BULLETIN 346

JUNE 1963

Effect of SEED SIZE on VIGOR and YIELD of RUNNER PEANUTS
n Y

70
SIIT

"

OCT

AGRICULTURAL

EXPERIMENT

STATION

AUBURN
E. V. Smith, Director

UNIVERSITY
Auburn, Alabama in cooperation with

CROPS

RESEARCH DIVISION,

USDA AGRICULTURAL

RESEARCH

SERVICE

CONTENTS
Page
EXPERIMENTAL PROCEDURE --------------4

Greenhouse Experiments ----Field Experim ents -- -- -----

-----

- --

--

-5

--- -- -- --- -- - -- -- -- 6 7

RESULTS AND DISCUSSION -------------------------------

Plant Vigor in Relation to -Seed Classes -----------------

7

Yield in Relation to Seed Classes-----------------------12 Characteristics of Peanut Kernels in Relation to Size of Seed Planted --------------------------------- 14
S UMM A RY -- - - - - - - - - - - - - - - - - - - - --- - - - - - - - - ---- - - - - - - - -1 LITERATURE CITED

6

---------------------- 7--------------17

ACKNOW LEDGMENT--------------------------------------18

FIRST PRINTING

3 M,

JUNE

1963

Effect of

SEED SIZE on VIGOR and YIELD of RUNNER PEANUTS
AUBREY C. MIXON, Agronomist, USDA-ARS, CRD

N

INETY per cent of Alabama's peanut acreage is in 12 southeastern counties. In 1961, Alabama farmers harvested from 193,000 acres approximately 210,370,000 pounds of peanuts with an estimated value of $22,000,000. Peanuts rank third in value among field crops, in the State. Each year some Alabama farmers use small seed known as "pegs" to plant their peanut acreage. These "pegs" are peanuts that pass through standard grading screens used by the seed processors to obtain No. 1 seed. Most "peg" seed, which are frequently referred to as "shrivels," are immature, as indicated by longitudinal wrinkles in their coats. No. 1 peanut seed are largely fully mature with only a small percentage of immatures. The greater vigor of seedlings from larger seed has been generally recognized for many years. In 1901 Miller and Pammel (8), working with small and large seed of several legumes, noted that in most instances larger seed produced more vigorous seedlings. Similar conclusions have been drawn from work with both grasses (4,7,10,11) and other legumes (1,2,3). In 1919 Kidd and West (6) indicated that larger seed resulted in more vigorous plants and higher yield. Higgins and Bailey (5) and Parham (9) have presented evidence that No. 1 peanut seed produce more vigorous seedlings than "peg" seed. Woodroof (12) presented a 3-year summary from a field emergence study, showing that No. 1 machine-shelled peanuts gave 76 per cent emergence as compared with 67 per cent

4

ALABAMA AGRICULTURAL EXPERIMENT STATION

for medium "pegs" and 57 per cent for small "pegs." Poor emergence of peanut plants grown from "pegs" was also noted by Higgins and Bailey. Reduced yields of peanuts grown from "peg" seed were noted by Woodroof (13,14) and Higgins and Bailey. In 2 out of 3 years with Virginia Bunch 46-2 in Virginia, ' yield of pods, shelling percentage, and per cent extra-large kernels increased with increasing seed size. The experiments reported in this bulletin were conducted to answer questions in regard to yield and vigor of peanut plants grown from seed of various seed size classes. EXPERIMENTAL PROCEDURE Mechanically-shelled peanut seed grown at the Wiregrass Substation, Headland, Alabama, were separated into seed size classes using various peanut-grading screens. The seed classes were selected from single lots of Dixie Runner peanut seed for use in the 1958 greenhouse experiments and for the 1959 and 1960 field experiments. The Early Runner variety was used in the 1961 experiment. After separation into size classes, the seed were hand selected to remove any visibly damaged kernels. Five seed size classes, (small, medium, and large No. 1 seed and small and medium "pegs") were used. The number of seed per pound for each seed class used is given in Table 1. A representative sample of each seed class is shown in Figure 1.
TABLE

1.

PEANUT SEED PER POUND OF VARIOUS

SEED CLASSES

Seed classes

Seed per pound Seed range Average No. No. 83 2 1,024 1,264 1,792 2,688

Classes of No. l's L arge -----------------------------------------------------------Medium Small Classes of "Pegs" Medium Small

8 0 0- 8 8 0 976-1,072 1,200-1,280 1,744-1,856 2,656-2,704

1 Unpublished results of cooperative studies by the Tidewater Research Station, Virginia Agricultural Experiment Station, Holland, Virginia, and the Crops Research Division, Agricultural Research Service, U.S. Department of Agriculture.

EFFECT

OF PEANUT

SEED

SIZE

5

4M

,t

ar.g
L

q( ed~f
u>--es 01 0\

itYQ) :
!"S
Seed

FIGURE 1. Peanut seed shown here are representative of five size classes. weight of seed shown for each class is approximately the same (2 grams).

GREENH~OUSE Exl'cnImNNS Preliiniarv experim~ents wxere condulctedl ill the mIeIho)IIe at Aubuihrn. Plantings wxere made Febru arx 12 and 27, 1955, in b~enches fhled with 9 inches of Norfolk sandy loam soil. Soil in the beniches was treated xx ith 4-12-12 fertilizer and g\ psiim at the rate of .500 and 2,000) potinids per acre, respectix ely . The fertilizer and gvpsiium were thoroug hlx mnixed in the soil hefore planting. HIeating cale were placed in the soil at the b~ottomn of the

b~enches to maintain soil temp~jeratulre at approximately 75°F.
tinder conditions wxhere air temperatures wxithin the greenhouse rangied from 34' to 104°F. Seed classes vveere replicated 7 times ini both plantin~gs. Each replicate consisted of three adjacent rowxs 36 inches long~ spaced 4 inches apart. Seed wvere spacedl 1 inch apart in the rows. Two wxeeks after seed were planted, the two outside rowxs of each plot wxere remov ed for clr\-,x eight determinations,

and the center rowxs wxere thinned to 10 plants. At the

end of another 2-week iutnte al (4 wxeeks after planting), the 10 plants that remained in each seed-class replicate were used to determine dTrv weight per plant.

6

ALABAMA AGRICULTURAL
FIELD EXPERIMENTS

EXPERIMENT STATION

Field experiments were conducted at the Wiregrass Substation on Norfolk sandy loam soil in 1959, 1960, and 1961. Each year various seed size classes were planted in randomized experiments with 6-inch drill spacing in 36-inch rows. Planting dates were April 17, 12, and 21 in 1959, 1960, and 1961, respectively. The 1959 experiment consisted of single row plots 38 feet long replicated 8 times. In 1960 and 1961, two-row plots 40 feet long were replicated 6 times. Five hundred pounds per acre of 0-10-20 fertilizer was applied broadcast in 1958 and 600 and 375 pounds per acre in 1960 and 1961, respectively. On the basis of soil analysis, 3,000 pounds per acre of high-calcium lime was applied prior to planting in the test area in 1960. Each year 500 pounds per acre of gypsum was applied broadcast to the potential pegging zone of peanut plants at early-bloom stage. The large No. 1 class of peanuts was planted at the rate of two seed per hill; other seed classes were planted at the rate of three seed per hill. All plots were thinned to one plant per hill shortly after emergence. In 1960 and 1961, a portion of the seed classes was also, planted at the rate of 50 pounds per acre with no thinning of plants. The spaced seed were planted with hand planters and the 50-pound-per-acre rate was dropped by hand in an open furrow and covered. Each year one plant from both ends of each plot row was removed for dry-weight determination at intervals of 4, 8, and 12 weeks from planting and immediately before harvest. At each sampling time, the two end plants in the space-planted plots were discarded and the third plant was used for dry weight. In the plots drilled at 50 pounds of seed per acre, one-foot at both ends of each row was discarded and the next plant in the row was used for dry weight. Plant samples used for dry-weight determination were dried at 155 0 F., and the weights were recorded in grams per plant. The single-row plots in 1959 and the double-row plots in 1960 and 1961 were adjusted to 30 feet in length before harvesting for yield, which was recorded in pounds of pods per acre. Pod samples of 200 grams per plot were used in determining market grade data. Pre-emergence herbicide, DNBP (4, 6 dinitro-o-secondary butyphenol), was applied in a 12-inch band on the row at the rate of 3 pounds per acre immediately after planting. This treatment

EFFECT

OF PEANUT SEED SIZE

7

controlled most anl xed'(s for 4 to 6 we eks. Conv entionial culiw tixvation wvas used throughout the remainder of the season. Plots wxere dusted w ith a DD)T-sulfur mixture for leaf spot and~ insect control. RESULTS AND DISCU.SSION
PLUNT \IGoiu 1S RELATION TO SEED CLASSES Drveighs ofplants xx crc not sigrnificantlx different between

the two green house experiments. Therefore, the resulIts "were cont-

bineci in Figure 3. Since the dlry-w eight deterinationis were used
as a measure of xigor, these pmeasures are uisedl to express x igor (diflerenees. The greater \ igor of seedlings g5aowx from each successixvely larger seed size w as cevidlent 2 and 4I wxeeks after planting. F'our wxeeks we rc required for plants from small and medimi ~pegs" to attain size of 2-wxeek-olol planits from tnediliii ando large. No. I seed. A rcpresentatx e seedllin g grown fromt each of the
seed classes is show ii in Figure 2.

At the end of 2 w eeks, plants from large No. I seed were ox ei

FIGURE 2. Peanut seedlings above were selected two weeks after planting five seed size classes; L. to R. Seedlings grown from small and medium "pegs" and from small, medium, and large No. 1.

8

ALABAMA AGRICULTURAL

EXPERIMENT STATION

.5 c 1.5
C

Two Weeks after planting

Four Weeks

After Planting

S

1.0l
.80 I .62 .435 . 27 .33. 3I .69

.

0.5

smalplemed.

small

med.

large,

Pegs

Classes 'of No.

I's

small

med. i

small

med.

large,

Pegs

Classes of No.

I's

FIGURE 3.

Dry weights of peanut seedlings 2 weeks and 4 weeks after planting
Significance at

various seed size classes in greenhouse in 1958 are shown here.

.01 level is .02 for 2 weeks and .07 for 4 weeks.

3 times as heavy as those from small pegs; at 4 weeks this superi-

ority was much less. Data from the field experiments (1959, 1960, and 1961) on vigor of plants obtained 4, 8, and 12 weeks after planting and at harvest are presented in Figure 4 and Tables 2 and 3. Averages of the data from spaced plantings for these years show that larger seed resulted in more vigorous plants than smaller seed at every stage of development. When considered on a yearly basis, all classes of No. 1 seed in the spaced plantings produced more vigorous plants throughout the growing season than did small "pegs" (Tables 2 and 3). Similarly, all classes of No. 1 seed produced more vigorous plants each year at 4, 8, and 12 weeks than medium "pegs" and throughout the growing season in 1960 and 1961. Seedlings from No. 1 seed emerged earlier and grew faster than those from small or medium "pegs." However, as the season progressed, the superiority in vigor of plants from large seed became less pronounced. For example, on the basis of the average for 3 years, plants from large No. 1 seed were about twice the size of those from small "pegs" 4 and 8 weeks after planting. At 12 weeks this superiority was only about 48 per cent, and by harvest only 35 per cent. Vigor relationships among seed classes at different stages of plant development are shown graphically in Figure 4. The extent to which plants from small seed gained in growth on plants from larger seed and the stage of growth during which

TABLE 2. WEIGHTS OF PEANUT PLANTS TAKEN FROM FIELD PLANTINGS APPROXIMATELY

4 AND

8 WEEKS AFTER PLANTING

0 on

Seed class

1959 G.

Four weeks from planting 1960 1961 Av.

Relative
wt.

1959 G. 22.7
15.1

Eight weeks from planting 1960 1961 Av. G. 18.2
13.2

Relative
wt.

z
C

G. 1.32
1.09

G. .97
.97

G. 1.07
.92

Pct. 218
188

G. 26.6
26.6

C. 22.5
18.3

Pct. 199
162

6-inch drill spacing Number l's
LargeMedium

.93

Small-Pegs

.72 .49
.46 .28

1.08 .65 .88 1.24 1.05

.65 .47 .27 .74 .52 .26
.11

.75 .53 .49 .99 .79 .31 [.15]11
(.17)
2

153 108 100 319 255 100

12.9 8.9 9.3

12.8 10.5 9.3 14.8 10.3 5.2 2.0 3.6

21.4 18.1 15.4 21.3 16.9 11.8 5.3 7.0

15.7 12.5 11.3 18.1 13.6 8.1 [2.8] (3.1) [3.7] (4.1)

139 111 100 223 168 100

N

mI

Medium Small---------- -501 pounds per acre in drill Number l's
L arge----------

Small-Medium----Pegs

--

Small

------------

__ _
.17

.37
.33

L.S.D. at .05 L.S.D. at .01
1L.S.D. 2L.S.D.

4.8 6.5

.24

.44

.15

[.21] (.23)

for first five classes in brackets. for 2-year averages in parentheses.

O

TABLE 3.

WEIGHTS OF PEANUT PLANTS TAKEN APPROXIMATELY Twelve weeks from planting

12 WEEKS AFTER PLANTING AND AT HARVEST
Immediately before harvest

Seed class

15 G.

90
199 16

16
91 A.

v

Relative

wt.

15
15

90 90 G. 205.4 186.9 155.9
43.4

16
91 A.

v

Relative
wt.

G. 77.2 88.5 55.0 50.6 67.0 ___ 69.9 ___ 49.6
___ 22.9

G. 88.6 90.0 81.1 67.5 47.1 67.7 53.3
36.3
8.0

G. 73.6 72.6 60.2 51.3 49.8 68.8 51.8
29.6

Pct. 148 146 121 103 100 232 173
100

G. 94.3 103.1 83.7 95.5

G. 106.7 103.7 90.9
78.4

G. 135.5 131.2 110.2
106.2

Pct. 133 129 108
104

6-inch drill spacing Number l's Large
Medium

Small
Pegs
Medium

54.9 39.2 44.6 35.9 35.2

Small ---------- -50 pounds per acre in drill
Number l's
L arge -----------

97.0

143.0 ___ 194.9
92.3

86.7 91.1
70.7

101.7 143.0
81.5

100 259
148

C
7-

Small-Medium----Pegs

Small -----------L.S.D. at .05 L.S.D. at .01

54.9
N.S. N.S. 43.7 58.6

55.5
26.3 35.3

55.2
[20.9]

100
-

16.2

22.4

[9.8]1
(11.7)2

(25.1)
[27.8] (33.3)
m

N.S.

30.1

10.7

[ 13.0] (15.5)

L.S.D. for first five classes in brackets. 2L.S.D. for 2-year averages in parentheses.

z
-a
a.

-t

z

EFFECT

OF

PEANUT

SEED

SIZE

11

EFFECT OF PEANUT S'EED SIZE

1

major changes in vigor relationships among seed classes occurred
varied from season to season.

Changes in plant vigor of Early Runner (1961) as the season progressed showed that differences in vigor associated with seed size were still evident 12 weeks after planting. Changes in plant

3 YEAR

AVERAGE

(1959- 1961)

EARLY RUNNER (1961)

/

WKS.

,WKS.

2 WKS.

I

HARVEST

small PEGS

med.

small

med.

large
1

small PEGS

med.

small

med.

large

CLASSES OF NO. I'S

CLASSES OF NO.'S

FIGURE 4. Percentage relations of dry weight of peanut plants grown in 6-inch drill spacing and sampled approximately 4, 8, and 12 weeks after planting and immediately before harvest are shown above.

12

ALABAMA AGRICULTURAL EXPERIMENT

STATION

vigor associated with seed size of Dixie Runner (1959-1960) were much less evident 12 weeks after planting. When plants were seeded at the rate of 50 pounds per acre, plants from larger seed were more vigorous throughout the season in 1960 and 1961 than those from smaller seed. The tendency of plants from small seed to catch up with those from larger seed as the season progressed was, much less evident in drill plantings when no thinning was done. On the basis of the 2-yeax average, plants from large No. 1 seed, which were about 3 times the size of those from small pegs 4 weeks from planting, were still about 21/2 times as large as plants from small pegs at harvest. This result is not surprising because in the unthinned plots the plants from large No. 1 seed had nearly 3 times as much space in the row in which to develop; whereas, plants from small "pegs" were much thicker in the row because of their smaller size. The greater vigor of seedlings produced from No. 1 seed was evident in both the spaced and the drilled plantings. This greater vigor should favor rapid emergence and establishment of healthy plants. The rapid ground cover produced by the more vigorous plants makes early cultivation and weed control easier.
YIELD IN RELATION TO SEED CLASSES

The effects of seed size on pod yield are shown in Figure 5 and Table 4. The 3-year average for pod yield gave the same general pattern as that for plant vigor. The larger the seed planted, the higher the pod yield in the spaced plantings with one exception. Because of nearly 20 per cent fewer plants at harvest, pod yield from large No. 1 seed averaged slightly less than that from other No. 1 seed. Small "pegs" were exceeded in yield by medium "pegs" by about 150 pounds per acre (8%) and by small and medium No. l's by over 200 pounds per acre (11 to 12%). When planted at the rate of 50 pounds of seed per acre in 1960 and 1961, No. 1 seed outyielded small "pegs" by about 175 pounds per acre (8%). Differences in pod yield associated with size of seed were small in 1959 and 1960, but were greater in 1961. Differences were in favor of No. 1 seed all years. In 1961 with Early Runner, small and medium No. 1 seed outyielded medium "pegs" by 163 to 211 pounds per acre (8 and 10%), respectively, and small "pegs" by 863 and 411 pounds per acre (18 and 20%).

EFFECT

OF

PEANUT

SEED

SIZE

13

EFFECT

OF PEANUT SEED SIZE

13

small

medium

CLASSES OF NO.

I'S

See clas FIGURE 5. Above are yields of peanuts grown from various seed size classes.
TABLE 4. POD YIELD OF PEANUTS GROWN FROM VARIOUS SEED SIZE CLASSES

1959

Yield per acre 1960 1961

Av.

Relative yield

Lb. 6-inch drill spacing
Number

Lb.
2,577 2,517 2,493 2,565 2,372

Lb.
2,347 2,468 2,420 2,257 2,057

Lb.
2,012 2,049 2,041 1,978 1,831

Pct.
110 112 111

Large------------------Medium Small ------------------Pegs

's

1,113 1,162 1,210 1,113 1,065

Medium----------------Small ------------------l's Large-------------------

108 100

50 pounds per acre in drill
Number

Small-Medium -----------Pegs Small-------------------L.S.D. at .05
L.S.D. at .01
1 L.S.D. 2 L.S.D.

--

2,517
2,638

2,372
2,323

2,444
2,481

107
109

-

N.S.
N.S.

2,468 N.S.
N.S.

2,105 195
261

2,287 (N.S}'2
[N.S.] (N.S.)
1

100

[162]1

for first five classes in brackets. for 2-year averages in parentheses.

14

ALABAMA

AGRICULTURAL

EXPERIMENT

STATION

When seed were planted at the rate of 50 pounds per acre, the plants grown from small-medium and large No. 1 seed of Early Runner outyielded those from small "pegs" by 218 and 267 pounds per acre (10 and 13%), respectively. In years when striking vigor differentials persist until late in the season, pod yields tend to be positively correlated with size of seed. In other years when plants from small seed tend to catch up with the larger plants from large seed early in the season, yields from "peg" seed may closely approach those from No. 1 seed. Results of these seed size studies are in general agreement with similar studies with runner and Spanish peanuts in Georgia (5) and Virginia (unpublished).
CHARACTERISTICS OF PEANUT KERNELS IN RELATION

TO SIZE OF SEED PLANTED

Results of data on pod samples taken from the field experiments in 1959, 1960, and 1961 are presented in Tables 5 and 6.

No shelling percentage differences were evident between peanuts produced from any of the seed size classes (Table 5).
TABLE 5. PER CENT PLANT STAND AT HARVEST AND SHELLING PERCENTAGE OF 200 GRAM SAMPLES OF PODS TAKEN FROM PEANUT SEED SIZE TESTS, 1959-1961

Seed class

Per cent plant stand at harvest 1959 1960 1961 Av. Pct. Pct. Pct. Pct.

1959

Shelling percentage 1960 1961 Av. Pct. Pct. Pct. Pct.

6-inch drill spacing

Number l's
Large....... Medium..... 81.0 98.3 80.9 97.9 84.7 92.2 82.2 96.1 74.8 74.1 71.2 70.9 76.0 75.9

73.8 73.6

Small....... Pegs
Medium..... Small.......

97.9
96.2 94.1

98.9
95.5 82.7

99.3
98.5 97.7

98.7
96.7 91.5

74.8
73.6 74.3

70.1
70.4 70.5

76.1
75.4 75.3

73.7
73.1 73.4

50 pounds per acre in drill Number l's Large....... Small-Medium

71.2 72.2

75.7 75.7

73.4 73.9

Pegs Small...
L.S.D. at .05 L.S.D. at .01

....
4.7 6.4 4.4 6.1 4.3 5.8 2.6 3.5 1.8 1.8

71.1
1.1 1.5

74.9
1.3 1.7

73.0
0.8

(0.8)'
1.0

(1.1)

SL.S.D. for 2-year averages within parentheses.

EFFECT

OF

PEANUT

SEED

SIZE

15

TABLE 6. PROPORTION SOUND MATURE KERNELS AND SEED COUNT PER OUNCE FROM SHELL POD SAMPLES TAKEN FROM PEANUT SEED SIZE TESTS, 1959-1961

Proportion

Seed class

sound mature kernels 1959 1960 1961 Av. Pct. Pct. Pct. Pct.

Seed count per ounce 1959 No. 1960 No. 1961 No. Av. No.

6-inch drill spacing Number l's Large --........... 93.1 Medium 92.4 Small______________ 92.7

-........

88.5 86.8 86.8 86.5 86.4

86.8 87.4 87.9 84.7 86.6

89.9 89.2 89.2 88.0 89.0

62 62 61 63 64

63 66 66 65 65

58 58 53 54 54

59 60 61 61 61

Pegs
Medium__________ Small________ 91.6 92.7

50 pounds per acre Number l's
Large ......... Small-Medium 86.3 89.5 87.3 2.2 2.9 87.7 88.7 85.6 1.7 2.2 87.0 89.1 86.5 0.9 .. 2.5 3.4 65 64 63 3.0 4.0 53 52 53 1.7 2.3 59 58 58 1.4

Pegs
Small ........ L.S.D. at .05 L.S.D. at .01 1.8 2.5

(1.4)2
1.2

(1.8)
1.8

(1.9)

(2.3)

'Proportion of seed riding 15/64-inch screen in 1959; 16/64-inch screen in 1960 and 1961. 2 L.S.D. for 2-year averages within pareni

Three-year averages of the proportion of sound, mature kernels from field plantings produced by the No. 1 seed size classes in the 6-inch drill spacing were greater than those from medium "pegs." Only the large No. 1 seed class produced a significantly greater proportion of sound, mature kernels than small "pegs." Data on seed count per ounce indicate that mature shelled peanuts produced from large No. 1 seed were slightly larger than those produced from small No. 1 or medium "pegs." As indicated, these larger seed were from one of the larger seed size treatments that produced vigorous plants. The larger seed probably resulted from greater food storage in the cotyledons when produced on more vigorous plants. If seed stock used consisted of a mixture of genetic seed sizes, continued selection of the larger seed for several generations would likely screen out genetically larger peanut seed that would breed true for large seed size.

16 16

ALABAMA

AGRICULTURAL

EXPERIMENT

STATION

ALABAMA AGRICULTURLEPIMNSTIO

SUMMARY Experiments in the greenhouse at the Auburn Agricultural Experiment Station in 1958 and in the field at the Wiregrass Substation in 1959, 1960, and 1961 were conducted to determine vigor and yield differences between peanut plants grown from various seed size classes. The results are summarized as follows: 1. Peanut seedlings grown from No. 1 seed emerged earlier and grew off faster than seedlings from small or medium "peg" seed. This greater vigor was evident throughout the season. 2. No. 1 seed resulted in higher pod yields than small "peg" seed in both 6-inch drilled plantings and in 50 pounds per acre plantings. Small and medium No. 1 seed produced 214 pounds per acre more than small "pegs" in spaced plantings and 194 pounds per acre more in drilled plantings. Two hundred fourteen pounds of pods at 11 cents per pound would be $23. In 1961, the average increase of 387 pounds per acre of pods from small and medium No. 1 seed over small "pegs" would be valued at $42. 3. Only well-developed No. 1 peanut seed are recommended for planting in Alabama. Such seed favor rapid emergence, vigorous early growth, less difficulty in controlling weeds, and usually result in appreciably higher yields than smaller seed.

EFFECT

OF

PEANUT

SEED

SIZE

17

LITERATURE CITED (1) L. A. The Effect of Alfalfa Seed Size and Depth of Seeding Upon the Subsequent Procurement of Stand. Agron. Jour. 38:964973. 1946. (2) HAWK, V. B., AND WELCH, A. W. Tolerance of Varieties of Smooth Bromegrass, Bromus inermis Leyss., to Injury by Root Rot, Pythium graminicola Subr. Agron. Jour. 40:809-817. 1948. (3) HENSON, PAUL R., AND TAYMAN, L. A. Seed Weights of Varieties of Birdsfoot Trefoil as Affecting Seedling Growth. Crop. Sci. I:206. 1961.
ERICKSON,

(4) HERMANN, E. M., AND HERMANN, W. The Effect of Maturity at Time

(5)

of Harvest on Certain Responses of Seed of Crested Wheatgrass, Agropyron cristatum (L) Gaerta. Agron. Jour. 31:876-885. 1939. HIGGINS, B. B., AND BAILEY, WALLACE, K. Peanut Seed and Seed Treatment. Ga. Agr. Expt. Sta. Mimeo. 70. 1959.

(6) KIDD, F., AND WEST, C. Physiological Predetermination: The Influence of the Physiological Condition of the Seed Upon the Course of Subsequent Growth and Upon Yield. Am. Appl. Biol. 5:112-142. 1919. (7) KNEEBONE, WILLIAM R., AND CREMER, CAROLos L. The Relationship of Seed Size to Seedling Vigor in Some Native Grass Species. Agron. Jour. 47:472-477. 1955. (8) MILLER, F. G., AND PAMMEL, L. H. A Study on the Germination and Growth of Leguminosae, Especially with Reference to Small and Large Seed. Iowa Agr. Expt. Sta. Bul. 62. 1901. (9) PARHAM, S. A. Peanut Production in the Coastal Plain of Georgia. Ga. Coastal Plain Expt. Sta. Bul. 34. 1942. (10) PLUMMES, H. P. The Germination and Early Seedling Development of Twelve Range Grasses. Agron. Jour. 35:19-34. 1943. (11) ROGLER, GEORGE A. Seed Size and Seedling Vigor in Crested Wheatgrass. Agron. Jour. 46:216-220. 1954.

(12)

WOODROOF, NAOMI C. Twenty-fifth Annual Report. Ga. Coastal Plain

Expt. Sta. Bul. 42, p. 34. 1945. Twenty-sixth Annual Report. Ga. Coastal Plain Expt. Sta. Bul. 43, p. 18. 1946. Thirtieth Annual Report. Ga. Coastal Plain (14) ---------------.---Expt. Sta. Bul. 49, pp. 31-33. 1950.

(13) ----......

18

ALABAMA AGRICULTURAL EXPERIMENT STATION

ACKNOWLEDGMENT The author acknowledges the assistance of C. A. Brogden, superintendent, and other personnel of the Wiregrass Substation, Headland, Alabama. Also, valuable suggestions in setting up the study were made by Wallace K. Bailey, leader, Peanut Investigation, Crops Research Division, Agricultural Research Service, U. S. Department of Agriculture, Beltsville, Maryland.