' APIF Ev'
I
~ 4%
Greenleaf 
Tabasco,
a New Tobacco Etch
Virus Resistant
Tabasco Pepper Variety
( Ca psicum [rutescens L.)
A G RI CU LTUJR AL F=X P FRI M EN T S T ATIO N
E. V. Smith, Director AUBU RN U N IV I RSITY 
Auburn, Alabama
SUMMARY
A new tobacco etch virus (TEV) re-
sistant Tabasco pepper variety (Cap-
sicum frutescens L.) named Greenleaf
Tabasco (Tabasco G) has been devel-
oped at the Auburn University Agricul-
tural Experiment Station. TEV, which is
widely distributed in the South on sola-
naceous host plants and transmitted by
aphids, causes a serious wilt disease of
the commercial Tabasco variety, threat-
ening its survival and consequently that
of the Tabasco hot sauce industry. The
new variety removes this threat from the
industry. In addition, the new variety
has resistance to ripe rot, a more con-
centrated fruit set, a darker red mature
fruit color, a brighter yellow immature
fruit color, and a higher pungency.
Two Indian pepper introductions of C.
chinense Jacquin from Peru, P.I. 152225
and P.L 159236, were the sources of
these improvements.
ON THE COVER
Plant at top is the tobacco etch virus (TEV) 
resistant Greenleaf Tabasco. Center left
is P. I. 152225 with orange red fruit. Center 
right is P. I. 159236 with glossy, dark
chocolate colored fruit. Note that up to three 
fruits are set per axil in Capsicum chinense
and up to two in Capsicum frutescens. 
Bottom left shows fruit of the TEV 
resistant Green-
leaf Tabasco, at right is fruit of the TEV susceptible 
commercial Tabasco variety showing
the typical ripe rot symptom on the third 
fruit from the right.
FIRST PRINTING 3M, DECEMBER 1970
Greenleaf Tabasco, a New 
Tobacco Etch Virus
Resistant 
Tabasco 
Pepper 
Variety
(Capsicum [rutescens L.)
W. H. GREENLEAF, J. A. MARTIN, J. G. LEASE,
E. T. SIMS and L. O. VAN BLARICOM
2
,3
A CCOuNTS of the McIlhenny Company
of Avery Island, Louisiana (7) and of
the Trappey and Sons Company of New
Iberia, Louisiana (15), indicate that
seeds of a fiery hot Indian pepper were
introduced into Louisiana, probably-from
the State of Tabasco in Mexico, about
1848.
The fine qualities of this pepper for
making a vinegar extract, used as a con-
diment and as an aid to digestion, were
soon recognized, around New Orleans.
The pepper itself was named Tabasco for
the state from whence it came. How-
ever, it was not until after the Civil War
that Edmund Mcllhenny, a New Orleans
banker and gourmet, perfected a super-
ior hot sauce made from the fermented
mash of red ripe Tabasco peppers. He
obtained a patent for the process in
1870.
McIlhenny's Tabasco sauce, which is
made on the family plantation on Avery
' The senior author acknowledges grant
support from the McIlhenny Company,
Avery Island, Louisiana.
' Respectively, Professor, Department of
Horticulture, Auburn University; Associate
Professor of Horticulture; Nutrition Asso-
ciate, Food Science and Biochemistry; As-
sociate Professor of Horticulture; and Pro-
fessor of Horticulture, all of Clemson Uni-
versity. Dr. J. G. Lease is currently Pro-
fessor of Foods and Nutrition, School of
Island, soon became internationally 
fa-
mous. This salt dome island provides
not only the Tabasco peppers but 
also
the large quantity of salt needed for 
the
fermentation process by which this sauce
is made. The pepper mash with salt
added is packed into 50-gallon Kentucky
white oak barrels, covered with a layer
of salt, and allowed to ferment for 3
years. The mash is then filtered, homo-
genized, diluted 1:3 with vinegar, and
bottled (9, 10). Since 1946, the name
"Tabasco" has been the permanent trade-
mark for the hot sauce of the McIlhenny
Company (8).
In addition to its culinary history, the
Tabasco pepper has an interesting
"virus" history 
that began at 
the Georgia
Agricultural Experiment Station, Experi-
ment, Georgia in 1945. There the Ta-
basco variety was included in a collec-
tion of peppers being screened by Green-
leaf for resistance to the bacterial leaf
spot disease for breeding a resistant
Home Economics, Montana State Univer-
sity, Bozeman, Montana.
SThis publication is a cooperative 
effort
of the Departments of Horticulture of Au-
burn University and of Clemson University.
Greenleaf developed the new Greenleaf
Tabasco pepper variety; Martin made the
chemical pungency tests; Lease made quali-
tative and quantitative determinations of
the various fruit pigments; Sims determined
juice yields; and Van Blaricomb determined
fruit color.
[3]
pimiento. The Tabasco plants, however,
died from an unknown wilt disease early
in July, just as they were beginning to
fruit. Of the many peppers in the collec-
tion, only Tabasco was thus affected. In
1946, the disease reappeared, killing all
plants except the two which had been
covered with insect-proof cloth cages.
In 1947, Greenleaf moved to the Agri-
cultural Experiment Station at Auburn,
where the disease was also observed in
the field. Prior to 1947, Weimer, formerly
USDA plant pathologist at Experiment,
Georgia, had suggested that the disease
had the characteristics typical of a virus
disease, thus focusing attention on this
possibility.
In 1949, Perry (1) succeeded in trans-
mitting the disease to two of four healthy
Tabasco plants by leaf inoculation with
extract from a wilted Tabasco plant with-
out the use of carborundum. However,
it was Holmes (4,5), of the Rockefeller
Institute for Medical Research, who first
identified the causal agent as tobacco
etch virus (TEV). He obtained the virus
from Alabama pepper samples sent him
by Greenleaf (1) in 1950. In the field
the virus is spread by aphids which ac-
counts for the high percentage of in-
fected plants. The unique wilt reaction
of Tabasco has since proved to be diag-
nostic for TEV (3).
Meanwhile, Younkin of the Campbell
Soup Company, Riverton, N.J. reported
in personal correspondence that P. I.
152225 from Peru, a variety of Capsicum
chinense Jacquin, had remained free of
symptoms following inoculation with
TEV. Greenleaf (2) subsequently
showed that this was not immunity but
a high level of resistance. This was
proved by a slow rate of virus increase
in inoculated plants and by their toler-
ance of the virus. The "etch" wilt reac-
tion of Tabasco was dominant in the F
1
hybrid (P.I. 152225 x Tabasco) and re-
sistance was inherited as a monogenic
recessive trait (2).
Holmes originally prompted the breed-
ing effort by Greenleaf to develop a
TEV resistant Tabasco pepper. He an-
ticipated that the disease would become
important to the Tabasco industry in
Louisiana, a prediction that has since
come true. Joseph Montelaro, Louisiana
State University Extension Service, wrote
in May, 1959: "We are having a lot of
trouble with the Tabasco variety. I know
that the growers in the St. Martin area
tell me that if something is not done
that they will have to discontinue pro-
ducing Tabasco pepper. You know that
this is a big business in Louisiana." By
this time, Greenleaf had begun to breed
TEV resistant Tabasco type peppers at
Auburn, but they were not yet commer-
cially acceptable for fruit type. Now a
highly desirable TEV resistant Tabasco
variety, illustrated on Page 1, has been
developed and is ready for release to the
industry.
ORIGIN OF GREENLEAF TABASCO
Tabasco is probably the only commer-
cially important pepper variety of the
species Capsicum frutescens L. in the
U.S. trade. Most other varieties are of
C. annuum L. (12). In the breeding of
Tabasco G, two strains of the Tabasco
variety were used. In the first crosses
a strain of the Reuter Seed Company of
New Orleans was used and later one
of the McIlhenny Company. Two TEV
and ripe rot resistant Indian pepper
cultivars from Peru, P.I. 152225 and
P.I. 159236, both of C. chinense Jacquin
(see illustration) contributed 
not only
TEV and ripe rot resistance to the new
Tabasco, but also improved fruit char-
acteristics. This was possible because
C. chinense crosses readily with C. fru-
tescens, and no serious sterility barrier
was encountered (13). Up to 
four back-
crosses to Tabasco were made, with
alternating selfed generations being
screened for "etch" resistance after each
backcross. Interline crosses were also
made at the third backcross level to
concentrate the genes for other desirable
plant and fruit characteristics. The pedi-
[4]
PEDIGREE OF GREENLEAF TABASCO
o 950 C. chinense C. frutescens C. chinense
PI. 152225 var. Tabasco PI-159236
o F F2BC3 Interline crosses F
o TEV F2
1F3 (ii Fl 61139 141 148 151 FBD
11956 F1B BLl
TEV F Double crossC2
o F3 14 FBC3
RC2 F, i
I ~Ft
TEV F Tabasco
O 196o FiBC3 1967 R BC4 F4BC3
ITE 
V FtI
@ TVF2F2 
1F6
0 1970 TEV F3 TEV Ft
Bulked l ines 70-1 70-516-1717A
(F4 seed) (F2 seed)
Abbreviations 
N
PI,P27P3 =Parents
R to F6 = Filial generations TABASCO
BDt to BC4= Back crosses
TEV= TEV screened generations
@0 Number of generations
gree of
figure.
Tabasco G is presented in the
CHARACTERISTICS AND PERFORMANCE
Plant Habit and Productivity. Two
distinct growth habit types, based on
the kind of branching, occur in the orig-
inal, Tabasco variety. The more desir-
able type produces plants with a fiat
top, bearing erect fruits well exposed for
picking. The other type bears fruit's in
racemes with drooping branches. Plants
of the first type are usually taller, and
when in full fruit present a stunning ap-
pearance. The fiat top habit seems dif-
ficult to stabilize genetically. Tabasco
C, like the original variety, is a mixture
of both plant types.
[5]
TABLE 1. COMPARATIVE PRODUCTIVITY OF SINGLE PLANT SELECTIONS OF TABASCO
AND TABASCO G IN 1969
Variety and line Total Total fruit Per cent Av. fruit
fruit weight fruit weight ripe fruit weight
No. G. No. G. Pct. G.
Tabasco 69-13 500 508 1.0060
69-18 840 860 1.0288
69-13 1,712 1,606 852 740 46.1 0.9381
Tabasco G------------ 69-2 2,041 1,910 1.0060
69-11 2,10831 2,142 1,328 1,438 67.1 1.0185
SBest single plant selections of each variety in the field.
Several observers independently agreed
that Tabasco G seemed more produc-
tive than the original variety. This 
was
verified by counting and weighing 
the
fruit of several of the better plants of
each. In 1969, the best Tabasco G 
se-
lection had 23 per cent more fruits than
the best Tabasco selection and 33 per
cent more fruit weight, Table 1. The
heavier fruit set of Tabasco G is prob-
ably a result of a greater fruit density
per unit length of stem.
Fruit Abscission. Easy abscission of
the fruit is a characteristic of economic
importance because it facilitates picking.
This trait is genetically dominant over
hard abscission (11) but various inter-
mediate degrees occur in the original
Tabasco variety. Despite rigorous selec-
tion for this trait, Tabasco G is still
variable in abscission but probably no
more so than Tabasco itself. Ease 
of
abscission improves with fruit maturity
and comparisons between plants or varie-
ties must be made with fruits of com-
parable maturity.
Fruit Size, Weight, and Shape. The
two varieties are similar in fruit size
and weight, 
Table 
2. In 
three years'
comparisons there was little difference in
fruit length, but Tabasco G fruits were
significantly broader, Table 2. Over the
years Tabasco G was selected for a
broadly conical fruit shape with a
rounded, smooth stylar tip in preference
to slender fruits with sharper tips that
would tend to catch on processing
screens.
Maturity. Tabasco and Tabasco G
are late maturing varieties that are
adapted only to areas having a long
growing season. When sown in peat
pots early in February and transplanted
to the field in the middle of April, har-
vesting of ripe fruit can begin in the
middle of August. Harvest of immature
fruit in the yellow-green stage could
start 2-3 weeks earlier. The plants con-
TABLE 2. COMPARATIVE SIZE AND WEIGHT OF MATURE FRUITS OF TABASCO
AND OF TABASCo G
Variety and year
Fruit Av. fruit Av. fruit
Fut length width
mm
80.42 b
30.09 b
81.76 a
80.46 b
29.46 b
29.57 b
mm-
7.88 b
8.14b
8.22 b
9.03 a
8.66 a
8.82 a
Fruit
No.
1,484
Av. fruit
weight
0.8430
500 1.2080
886 1.0963
1,500 1.1955
,2 Comparisons should be by years. Values followed by different letters differ significantly
at P < 0.01.
SFigures are meas means of bulk weights. A larger fruited strain of Tabasco was 
used in
1968 and 1969 than in 1967.
[6]
Tabasco
Tabasco
Tabasco
Tabasco G
Tabasco G
Tabasco G
1967
1968
1969
1967
1968
1969
No.
150
107
100
200
108
200
v v
TABLE 3. FRUIT COLOR, JUICE COLOR, AND SOLUBLE SOLIDS OF TABASCO
AND OF TABASCO G IN 1969
Variety and line Fruit colora Juice colorb Soluble solids
Pct.
Tabasco 69-13 Blood Red Capsicum Red 12.0
No. 820 No. 715/2
Tabasco G--------- 69-3 Currant Red Dutch Vermilion 10.6
No. 821 No. 717/1
Tabasco G--------- 69-11 Currant Red Dutch Vermilion 10.0
No. 821 No. 717/1
a,b Colors are from the British Horticultural Color Chart. The fruit and juice colors of
Tabasco were a considerably lighter red than those of Tabasco G.
tinue to fruit until killed by frost in late
fall.
Fruit and Juice Color. Immature fruits
of Tabasco G are a brighter yellow than
those of Tabasco. This should im-
prove the appearance of the whole-
pack product known as vinegar sauce.
Ripe fruit of Tabasco G are dark red
and glossy as if waxed. They range
in color from Currant Red No. 821 to
Cardinal Red No. 822 in the British
Horticultural Color Chart (6). Fruit of
Tabasco lack this high gloss. Their
color matches Blood Red No. 820, a
considerably lighter shade of red, Ta-
ble 3.
The juice colors of both varieties were
of a lighter tone than the external fruit
colors, but corresponded to the latter in
their relative intensity. Juice of Tabasco
G matched Dutch Vermilion No. 717/1
and Tabasco juice Capsicum Red No.
715/2, Table 3. Lease found that Ta-
basco G fruits had 39 per cent more ex-
tractable red pigments (capsanthin, cap-
sorubin, and zeaxanthin) than did Ta-
basco fruits. Colorimetric values deter-
mined by Van Blaricom confirmed the
darker red color of Tabasco G fruits,
Table 4.
Percentage Dry Matter and Juice
Yield. In the immature yellow-green
stage fruits of Tabasco and of Tabasco
G are firm and fibrous when crushed be-
tween the fingers, yielding little juice.
However, as the fruit matures it gradu-
ally turns into a bag of juice. It is this
property that makes Tabasco so uniquely
suitable for hot sauce. Paradoxically the
yellow-green fruit have a lower dry
matter content than red ripe fruit, while
orange fruit are intermediate in this re-
TABLE 4. MATURE FRUIT COLOR OF TABASCO AND TABASCO G
Colorimetric values with Gardner color difference meter
1
Variety and year 
RI a 
b a/b 
Color
2
No.
Tabasco 1967 8.03 46.7 15.5 2.69 Blood red 820
1969 9.30 34.7 19.3 1.80 Blood red 820
Tabasco G 1967 4.63 36.8 12.6 2.91 Cardinal red 822
1969 8.00 38.2 17.5 2.18 Cardinal red 822
1969 6.80 39.3 16.8 2.34 Cardinal red 822
' Color of fresh pepper, measured by a Gardner color difference meter with the following
standard plate values: RI - 7.9; 'a' - 61.0; 'b' 20.4.
RI indicates luminous reflectance. A lower reflectance index indicates a deeper, more
intense color. Higher 'a' values indicate more redness. Higher 'b' values indicate more
yellowness. A higher a/b ratio indicates a more attractive red color.
2 Color names and numbers are from the 
British Horticultural Color Chart pp. 166, 
168.
Cardinal Red is a darker red color than Blood Red.
SComparisons should be by years.
[7]
TABLE 5. PERCENTAGE DRY MATTER OF BULK SAMPLES OF TABASCO AND TABASCO G
FRUITS AT 3 STAGES OF MATURITY
Fruit colorDry matter Difference
Tabasco Tabasco G
Pct. Pct. Pct.
Dried in forced air oven at 52 C-Auburn '67
Red 31.0 22.9 26.0
Orange ---------------- ---- 27.3 21.0 23.1
Yellow-green 18.9 17.8 5.6
Dried in vacuum oven at 69 C-Auburn '67
Red 28.9 21.3 26.3
Orange----------------------- 27.9 21.3 23.7
Yellow-green 20.9 16.4 21.5
Dried in vacuum oven at 52 C-Clemson '67
Red 34.4 23.5 31.7
spect. The water in the immature fruit
appears to be physically bound whereas
it is relatively free in the mature fruit.
Mature fruit of Tabasco G had 26 per
cent less dry matter than those of Ta-
basco, Table 5. The expected increase
in juice yield from Tabasco G was not,
however, realized in Sims' tests. This
was probably because of the inability
of the Carver press to extract as much
juice as anticipated at the pressures used.
This can be seen by the difference ob-
tained when two pressures were used.
For example, at 10,000 psi the juice yield
from Tabasco was 58.5 per cent of the
fresh fruit weight, whereas it 
was only
23.8 per cent at 5,000 psi. Neverthe-
less, the highest juice yield, 55 per cent,
was from a Tabasco G sample, Table 6.
Soluble Solids and Pungency. In 1968,
soluble solids measurements were made
with a hand refractometer on the juice
of 30 individual ripe fruits of Tabasco
and on 42 fruits of Tabasco G. The
mean soluble solids of both varieties was
10.5 per cent, Table 6. In 1969, two
bulk samples of Tabasco G had 10.6
per cent and 10.0 per cent soluble solids,
respectively, and one bulk sample of
Tabasco, 12.0 per cent. The difference
in soluble solids between the two varie-
ties probably has little practical sig-
nificance, but the higher pungency of
Tabasco G fruit shown in both the 1967
and 1969 tests by Martin, Table 6, has
obvious economic importance for a hot
sauce manufacturer (14,16).
TABLE 6. JUICE YIELD, SOLUBLE SOLIDS, AND PUNGENCY OF TABASCO AND TABASCO G FUITS
Variety 
Fruit Juice 
yielda Soluble 
Pungencyb
Variety 
maturity 1967 
1969 solids 1967 
1969
Pct. Pct. Pct.
Tabasco Red 23.8 53.5 10.5 7.5 7
Orange 26.6
Yellow-green 26.7
Tabasco G -- ............. Red 44.0 8
Red 23.8 55.0 10.5 9.0 8
Orange 26.2
Yellow-green 22.7
a A Carver laboratory press was used. In 1967, samples of 73.5 g were pressed at 5,000
psi. In 1969, samples of 100.0 g were pressed at 10,000 psi.
b Chemical color test by Ting and Barron's methods. The color scale ranges from 1
mildest to 10 = hottest.
[8]
Seed Weights. Seed weights of two
Tabasco G lines were compared with
those of two Tabasco strains. One of
the latter was small fruited, the other
large. Five 200-seed samples of each
were weighed and the mean weight of
100 seeds of each calculated. The two
Tabasco G seed lots weighed 0.7720 and
0.7760 g/100 seeds, respectively, aver-
aging 58,603 seeds/lb. The Tabasco
seeds were significantly heavier, weigh-
ing 0.8880 g and 0.9030 g/100 seeds for
the smaller and larger fruited strain, re-
spectively, and averaging 50,602 seeds/
lb. Fruit size in Tabasco was thus in-
dependent of seed weight.
DISCUSSION
TEV Resistance. To maintain the
TEV resistance of Tabasco G, this va-
riety must be grown in isolation from
the commercial Tabasco, as any out-
crosses with the latter will be as highly
susceptible to the "etch" wilt disease
as Tabasco itself. Tabasco G breeds
true for resistance to the disease. Field
trials and controlled inoculation with
TEV over the past 20 years have dem-
onstrated the stability of this resistance.
The fear of a virus buildup in the new
variety that could threaten other more
susceptible pepper varieties in the field
has proved unfounded. Because Ta-
basco G has a lower rate of TEV multi-
plication in its tissues than 
do susceptible
pepper varieties that respond to infec-
tion with the typical leaf mottling symp-
tom (2), there would actually be less
virus buildup in it. Furthermore, TEV
is not seed transmitted. In the field most
Tabasco G plants are vigorous and ap-
pear to be healthy and free from TEV
mottling symptoms. The development in
the field of heavily TEV inoculated
seedling transplants into bushes bearing
satisfactory crops supports this infer-
ence. The evidence is that the TEV
resistance of Tabasco G is permanent
and horizontal as defined by Van der
Plank (17).
Ripe Rot Resistance. Ripe fruits of Ta-
basco are subject to a fruit rot that
first shows as an orange discoloration on
the red fruit, resembling sunscald, see
figure. The causal organisms have not
been identified. The fruit eventually
shrivels into a dry shell varying from a
straw color to a very dark red. Infected
fruits could spoil the pepper mash, or
in any case reduce its quality. Tabasco
G derives its considerable resistance to
ripe rot from its two C. chinense parents
shown in figure.
Higher Pungency of Tabasco G. The
higher pungency of Tabasco G fruits vs.
Tabasco fruits was a bonus of inter-
specific hybridization. This result was
most unexpected because the Tabasco
variety itself was already known to be
one of the most pungent of peppers and
because the pungency of the two C.
chinense parent cultivars was an unknown
quantity.
and in plant type is moderate, but no
greater than is commercially acceptable
and genetically desirable to maintain the
vigor and broad adaptability of the new
variety.
LITERATURE CITED
(1) GREENLEAF, W. H. 1953. Effects
of Tobacco-Etch Virus on Peppers
(Capsicum sp.). Phytopathology
43:564-570.
(2) GREENLEAF, W. H. 1956. Inheri-
tance of Resistance to Tobacco-Etch
Virus in Capsicum frutescens and
in Capsicum annuum. Phytopatho-
logy 46:371-375.
(3) GREENLEAF, W. H. 1967. A Wilt
Disease of Tabasco Pepper Caused
by Tobacco-Etch Virus. Exercise
No. 90, pp. 128-129. In A. Kelman
(ed.) Sourcebook of Laboratory
Exercises in Plant Pathology. W. H.
Freeman and Co., San Francisco
and London.
(4) HOLMES, F. O. 1942. Quantitative
Measurements of a Strain of Tobac-
[9]
co-Etch Virus. Phytopathology 32:
1058-1067.
(5) HOLMES, F O. 1948. The Filter-
able Viruses. Supplement No. 2,
Bergey's Manual of Determinative
Bacteriology, 6th ed. pp. 1127-1286
plus Index. The Williams and
Wilkins Co., Baltimore, Md.
(6) Horticultural Color Chart Issued by
the British Colour Council in Col-
laboration with the Royal Horti-
cultural Society. Copyright - Rob-
ert F. Wilson, 1938. Printed in
Great Britain by Henry Stone and
Son Ltd., Banbury.
(7) McIlhenny Company. 1958. Ta-
basco, its Romantic History, its
Wonderful Way with Foods and
75 Recipes from the Famous Ta-
basco Collection. Pamphlet, Copy-
right - Mcllhenny Company, Avery
Island, La.
(8) Mcllhenny Company. 1968. The
100 Year History of Tabasco and
10 Recipes that Helped Make it
Famous. Commemorative Bro-
chure, Copyright - McIlhenny
Company, Avery Island, La.
(9) MEAD, C. R. 1962. Hot Pepper
Haven. The Furrow, November-
December, pp. 2-3.
(10) SHALETT, SIDNEY. 1956. Hot Pep-
per Island. Sat. 
Eve. Post 228:43,
59,60,62.
(11) SMITH, PAUL G. 1951. Deciduous
Ripe Fruit Character in Peppers.
Proc. Amer. Soc. Hort. Sci. 47:343-
344.
(12) SMITH, PAUL G. AND CHARLES B.
HEISER, JR. 1951. Taxonomic and
Genetic Studies on the Cultivated
Peppers Capsicum annuam and C.
frutescens. Amer. 
Jour. Bot. 38:362-
368.
(13) SMITH, PAUL G. AND CHARLES B.
HEISER, JR. 1957. Breeding Be-
havior of Cultivated Peppers. Proc.
Amer. Soc. Hort. Sci. 70:286-290.
(14) TING, S. V. AND KEITH C. BARRONS.
1942. A Chemical Test for Pun-
gency in Peppers. Proc. Amer. Soc.
Hort. Sci. 40:504-508.
(15) TRAPPEY, B. F. AND SONS, INC. The
Secret of Creole Cooking. Un-
dated Pamphlet, New Iberia, La.
(16) VAN BLARICOM, L. O. AND J. A.
MARTIN. 1947. Permanent Stand-
ards for Chemical Test for Pun-
gency in Peppers. Proc. Amer. Soc.
Hort. Sci. 50:297.
(17) VAN DER PLANK, J. E. 1968. Dis-
ease Resistance in Plants. Academic
Press, Inc., New York.
[10 ]