Table Of ContentThe Pennsylvania State College
The Graduate School
Department of Agronomy
BREEDING LADINO CLOVER FOR PERSISTENCE AND LONGEVITY
A Thesis
by
WILLIAM ERIC KNIGHT
Submitted in partial fulfillment
of the requirements
for the degree of
DOCTOR OF PHILOSOPHY
June 11, 1951
Approved:
Department of Agronomy
/y«rv
Head of the Department
VITA
William Eric Knight, bom July 24, 1920 at Lacon, Alabama;
son of William Edwin and Annie (Patterson) Knight. He attended elemen
tary and high school at Falkville, graduating May 1938. He received
the B.S. degree in Agricultural Education at the Alabama Polytechnic
Institute, Auburn, 194-2. He was called into the army as Second
Lieutenant in the Field Artillery in June 1942; served overseas in the
European Theater of Operations; discharged from service, Captain,
August 1946. He taught Veterans Vocational Agriculture, Grand Ridge,
Florida, September 1946 until June 1947. He received the M.S. degree
in Agronomy at the Alabama Polytechnic Institute, December 1948. He
is an associate member of Sigma Xi and a member of Phi Kappa Phi,
Gamma Sigma Delta, Alpha Zeta, Kappa Delta Pi fraternities and the
Baptist Church. Married July 9, 1944 to Margaret Nell, daughter of
James Garfield and Audrey (Stinson) Liles of Falkville.
ACKNOWLEDGMENTS
The writer is indebted to Doctor W, M. I-iyers, Director of
Field Crop Research, Beltsville, Maryland, and formerly Senior
Geneticist, U.S. Regional Pasture Research Laboratory, State College,
Pennsylvania, under whose supervision the Ladino breeding investigation
was initiated.
Grateful acknowledgment is made to Doctor H. R. Albrecht,
Head of the Department of Agronomy, who as Advisor and Committee
Chairman was a source of encouragement and helpful criticizm throughout
the course of the work and in the preparation of the manuscript; and to
other members of the Advisory Committee who read and criticized the first
draft of the manuscript; Doctor V. G. Sprague, Doctor H. L. Carnahan,
Doctor R. P. Pennington, and Doctor J. E. Wright.
Appreciation is also expressed to Doctor R. J. Garber,
Director of the U.S. Regional Pasture Research Laboratory, State College,
Pennsylvania for providing laboratory and greenhouse facilities; to
Doctor V. G. Sprague, Senior Agronomist, for many helpful suggestions
in conducting the greenhouse investigations; and to Dr. A. A. Hanson,
Geneticist, for statistical advice and helpful suggestions in the
preparation of the manuscript.
The writer also wishes to express his gratitude to the
Cooperative Grange League Federation Exchange, Incorporated which made
this study possible through a fellowship grant. Sincere appreciation
is also expressed to the Honorable A. J. Sordoni, Secretary of Commerce
for the Commonwealth of Pennsylvania who so generously supplied land
and equipment for the experiment at Harvey's Lake, Pennsylvania.
TABLE OF CONTENTS
Page
IGTEiDiCVICN........................................................ 1
IE;; . ’ LEE.., E.E................................................ 2
SJCP-i '1 . TAL i\; EEf iR_.............................................. 9
A. Spaced PI ant in j of Lad in o Clones........................... 9
B. Ft_ Pro "cnies Between Good and Poor Clones............... 11
G. Ludino Polycross Progeny Tests...... ..................... 1A
a. Ladino polycross test planted alone
at State College, Pennsylvania................... 1A
b. La ino polycross test planted with
orchard rass at State College,
Pennsylvania..................................... 1A
c. Ladino polycross test planted at
Harvey’s Lake, Pennsylvania...................... 15
D. Greenhouse Investigations of Morphological
and Physiological Characters of Ladino..................... 16
a. Hate of growth, size of plant parts
and f1ow or ing.............. 16
b. Rooting investigations........................... 18
1. Rooting Ladino stolons cut int
sections on ir.oist paper toweling.......... 18
2. Rooting Ladino stolons whole
on r.oist paper toweling................... 18
3. Rooting Ladino stolonsi n sand............. 19
A. Rooting attached Ladino stolons on
flats filled with soil.. ................ 19
j 5. Cutting Ladino stolons to induce
rooting and branching............ 20
c. Intern ode length........ 21
d. Length of day investigations. ................ 21
e. Sclerctinia test............. 22
' - Page
E. Statistical ..................................... 23
EXPEli LTAL i- ..SuL-.i> *i.:fD ^-.oG oalLw •«..••»«.»•*•..•••••• •••••• •••••• 24
A. Spaced Plan tin." of Lad'Ino Clones................ 24
3. J?3_ Progenies Between Good and Poor Clones................ 26
G. Lad inc- Polycross TEsts..................................... 36
a. Ladino polycross test planted alone
at State College, Pennsylvania................... 37
b. Ladino polycross test planted with
orchardgrass at State College, Pennsylvania...... 4-0
c. Latino polycross test planted at Harvey’s
Lake, Pennsylvania............................... .41
D. Greenhouse Investigation of Morphological and
Physio"1 o yieal Characters of Lad inc 4-3
a. Rate of growth, size of plant parts and
flowering...................................... 43
b. Rooting investigations........................... 53
1. Rooting Ladino stolons on l oist paper
toweling -nd in sand...................... 53
2. Rooting attached Ladino stolons on flats
filled with soil.......................... 54
3. Cutting Ladino stolons to induce
rooting and branching............. 56
c. Sclerotinia tsst................................. 53
E. Interrelationships between Morphological and
Physiological Characters of Ladino Clover................. 59
P. Important Steps in the Synthesis of Improved Strains
of Ladino Clover.......................................... 62
SUMMARY AND CONCLUSIONS............................................. 66
LITE.Li.TURE CITED.................................................... 69
APPEI: DIX............................. 72
TEXT TABLES
Table Page
1. Comparative scores and measurements of parental clones
selected for greenhouse crosses........................ 9
2. Evaluation procedure used in determining differences in
the field between progenies grown at State College,
Pennsylvania from 1949-51................................ 13
3. Characters of Ladino clover plants compared in the
greenhouse during the winter of 1949-50 and the
method used to record the data........................... 17
4* Summary of average vigor and disease scores for surviving
clones in the spaced planting with all parental clones
included for comparison.................................. 25
5. Summary of average vigor and stand scores for 24
progenies of good and poor clones grown in simulated
broadcast stands at State College, Pennsylvania........... 30
6. Correlation coefficients of vigor and stand for 31 F-^
progenies.............................................. 31
7. Analysis of covariance of 1950 spring vigor and July 1950
vigor of F^ progenies, together with test of significance. 31
8. Average yields for 1950 in tons dry matter per acre from
24 Ft progenies of good and poor clones grown in simulated
broadcast stands at State College, Pennsylvania.......... 33
9. Correlation coefficients of vigor and yield for 24 F^
progenies......... 34
10. Average spring vigor scores for polycross progenies of
good and poor clones seeded alone and with orchardgrass
at State College, Pennsylvania and seeded alone at
Harvey's Lake, Pennsylvania........................•••••• 38
11, Average yields in tons dry matter per acre for 16 poly
cross progenies seeded alone and with orchardgrass at
State College, Pennsylvania and seeded alone at
Harvey's Lake, Pennsylvania..... ............... 39
11-*A. Vigor scores for good x good and poor x poor F-, progenies
for April 27, 1950 showing the spread in vigor Detween
crosses and the clone averages..................... 43
Table Page
12. Rate of stol-'n initiation for good end poor clones and
their >2. progenies s' owing the number of days required
for initiation of the first lateral, number of stolons
in 25, 3°, 50 and 75 days, together with the score for
number of stolons in 10 i days and the actual number
Juno J, 1750................................................ 45
13. Correlation coefficients of number of stolons and winter
survival sc "'res of Ladino cl over for l'Vfl-50................ 46
14. Stolon elongation in centimeters of first and second
stolons of four parent clones and four progenies
il.lustrati.ng the method used in recording elongation
data and showing the variability of this character.......... 4-7
15. Correlation coefficients for winter survival scores
and measurements of size of plant parts and flowering....... 4C
16. Response of twelve selected clones and four
progenies to 14 and 16 hour day length when grown
in the greenhouse during the winter of 1950-51.............. 52
17. The effects of two levels of moisture on the rate
of stolon elongation and on the production of roots
and lateral branches........................................ 55
1C. Correlation coefficients for winter survival and
measurements of stolons attached to the mother plant........ 56
19. The effects of two cutting treatments and two levels
of moisture on rooting and branching of stolons ....... 57
20. Correlation coefficients of disease measurements
and winter survival..................... 59
21. Correlation coefficients showing additional inter
relationships of characters of Ladino clover................ 60
22. Multiple and partial correlation coefficients of
winter survival and greenhouse measurements of
characters of Ladino clover................................. 61
APPENDIX TABLES
Table Page
I. Summary of Average Vigor and Stand Scores for 31
Progenies of Good and Poor Clones Grown in Simulated
Broadcast Stands at State College, Pennsylvania......... 73
II. Analysis of Variance of the Total Yields of F-^
Progenies Illustrating the Method Used............... 74
III. Analysis of Variance of Total Yields and Interactions
from 24 F-, Progenies of Good and Poor Clones for Three
Harvests in 1950...................................... 75
IV. Analysis of Covariance of 1950 Spring Vigor and 1950
Fall Vigor of 24 F]_ Progenies, Together with Test of
Significance......................................... 76
V. Summary of Average Yields for 1950 in Tons Dry
Matter Per Acre from 31 P]_ Progenies of Good and
Poor Clones Grown in Simulated Broadcast Stands
at State College, Pennsylvania........................ 77
VI. Average Vigor Scores for Polycross Progenies of
Good and Poor Clones Seeded Alone and with Orchard
grass at State College, Pennsylvania and Seeded Alone
at Harvey’s Lake, Pennsylvania....................... 78
VII. Average Adjusted Yields in Tons Dry Matter Per Acre
for Polycross Progenies of Good and Poor Clones Seeded
Alone and with Orchardgrass at State College,
Pennsylvania and Seeded Alone at Harvey’s Lake,
Pennsylvania. ...................................... 80
VIII. Rate of Growth in the Greenhouse of Parental Clones
and F-, Progenies Measured by the Average Number of
Days from Planting Until Expansion of 2, 4, 6, and 8
Leaves and by the Average Number of Leaves
Produced in 50 Days................ 32
IX. Average Rate of Elongation In Centimeters of First
and Second Stolons of Good and Poor Clones and Their
F]_ Progenies When Grown in the Greenhouse............ 84
X, Rate of Elongation of Selected Stolons of Good and
r Poor Clones and Their F-^ Progenies Measured in the
■ Greenhouse in Centimeters after the January 30 Harvest. 36
XI. Average Scores and Measurements in the Greenhouse of
Leaf Size, Stolon Size, and Internode Length of Good
and Poor Clones and Their F^_ Progenies............... 88
Page
XII. Average Greenhouse Yields of Good and Poor Clones
and Their Progenies in Grams Dry Matter Per Pot
When Harvested, January 30, 1950 and June 12, 1950....... 90
XIII. Average Measurements of Profusion of Flowering of
Good and Poor Clones and Their Progenies when
Grown with 16 Hour Day in the Greenhouse................. 92
XIV. Average Vigor Scores of Good and Poor Clones and
Their F-j_ Progenies Recorded in the Greenhouse During
Flowering on Three Dates....... 94
XV. Average Root Initiation Scores for Stolons fTatr Good
and Poor Clones and Their F-^ Progenies Rooted on Moist
Paper Toweling...... 96
XVI. Average Rooting Scores for Stolons from Good and Poor
Parental Clones Rooted in the Greenhouse in 1950 in
Flats Filled with Sand................................ 98
XVII. Average Disease Scores for ih Progenies Taken in the
Field in the Fall of 1950 and the Average Survival of
the Progenies When Tested in a Sclerotinia Inoculation
Chamber in the Spring of 1951........................ 99
FIGURES
Page
1. Field plots of F-j_ progenies April 2, 1950 showing
differential winter killing.................................. 27
2. Field plots of Fn progenies October 25, 1950 showing
the weedy condition of plots which were severely winter
killed......................................... 27
3. A portion of a plot of cross 96x103 April 2, 1950
showing typical winter injury of poor x poor F^p rogenies 100
4. A plot of cross 21x41 April 2, 1950 showing the
good survival of good x good F^ progenies................... 101
5. A field plot from the cross 21x31 Apr:'1 22, 1950
showing typical growth and vigor of the good x good
F^_ progenies.................................................. 102
6. A field plot from the cross 96x103 April 22, 1950
showing the type of growth in'1 amount of recovery
following winter injury of the poor x poor
pr ogenies.................................................... 103
7. Poor x poor cross 96x103 on the left and good x good
cross 21x31 on the right showing the condition of the
Fy progenies October 25, 1?50................................ 104
2. Leavos from throe Ladino clones illustrating the
range in size o f the pi- nts used and 'Heir v>. getative
response to length of day.................................... 105
9. Typical 12 weal: old F^ seedlings of good x good cross
89x21, on the left, and poor x poor cross 51x96, on
the right, shewing differences in the size of leaves,
petioles and numb r of stolons............................... 106
10. Plants with leaves r-r oved s!lowing differences in
the number of stolons........................................ 107
11. Four typical F-^ seedlings when 16 weeks old showing differences
in size, numbers of stolons and density of growth............ 108
12. Four typical fg sc idlings when 26 weeks old with the loaves
removed to show differences in the numbers of stolons........ 109
13. Ladino clover plants growing in one-half gallon glazed
pots between two flats filled with soil illustrating the
experimental proc- dure us-'d in rooting attached stolons on
soil.......................................................... 110
