s were exposed to
suggests that the
I or ph ys iological.
and placed in the
·ing the number of
that similar light
SS ibliit y that light
't normall y mainmilar to this were
ncandescent light
d duration durTno
ing light duratio~
cen tage than was
those reported bv
esulted in earlie-r
2 o C. The period
C took place also
:rees C during the
: longer tha; did
sts that the flower
sto rage period .
nts to flower were
were stored at a
1is is suggested by
the 2- rc temp
for flowering with
quite large. Less
:eding program in
; which are to be
nes. More impor'rmation . which is
d the mechanisms
jies in photoperiodY and night. J. Agr.
by in vivo spectroghl. Amer. J. Bot.
:on seed production
.:6 1- 63.
, bulb size, spacing,
CA . Agr. Exp . Stq.
11e levels assayed by
stems and storage
ol· so me economic
1
bulbs during cold
. Hart . Sci. 98:534-
plants. V. Effect on
. Jap an. Soc. Hart.
:nee of incandescent
: onion varieties. J.
l
I Effects of Nand K Fertilization on Internal and External Fruit Quality
of Three Major Florida Orange Cultivars 1
R. L. Reese and R. C. J. Koo
University of Florida, IFAS , Agricultural Research and Education Center, Lake Alfred
Abstract. This is a report of a 4 x 4 NK factorial experiment over a 6-year period using ' Hamlin' , 'Pineapple.' and
' Valencia' orange trees [Citrus sinensis (L.) Osbeck] on rough lemon rootstock (Citrusjambhiri Lu sh.) planted on
Astatula f.s .. formerly classified Lakeland f.s. Main effects of N and K we re considered independentl y because
interactio ns were not significant for most measurements. Increases inN rate increased the juice content and acid,
whereas increases in K resulted in higher acid and lower soluble solids with an accompanying lower soluble
solids/ acid ratio. Smaller sized fruit , more green fruit. and a lower pack out were a result of increased N rates.
Increased K rates did not influence external characteristics of the fruit other than producing larger fruit. Rind
blemishes occurred more often at the low N rate and diminished as the N rate increased. Incidence of decay in
storage was greatest at the lowest N rate. Creasing was found to be significantly related to high Nand low K rates.
Inte rnal and external fruit qualities of Florida oranges have been
reported by many authors (I, 4, 5, 6, 7, 8, 9). Data have often been
conllicting even with the same cultivars, and there was difficulty in
establishing a common point of reference between experiments.
Increased N was reported to have produced higher soluble solids (8, 9)
and lower soluble solids (4, 7) .
Reitz and Koo (4) found that higher rates of both N and K
increased the acid content in 'Valencia' fruit. They found no
signillcant differences in juice content due to N or K but reported
sign ificant increases in the soluble solids/acid ratio where low N and
K were applied.
Thin-skinned fruit were reported by Reitz and Koo (4) to have a
greater incidence of creasing, a physiological di so rder of rind , in low
potash plots I year and in low N plots another year. Sites and
Deszyck (6) concluded low rates of K were associated with fruit
creasing .
Deszyck et a!. (I) working with ' Hamlin' and 'Valencia' oranges
recorded an increase in fruit wt and diam as K rates were increased .
Reitz and Koo (4) reported increases in N applied to 'Valencia'
oranges reduced fruit sizes significantly, but K applications had no
signil'icant effect on fruit size. Fruit wt was signil'icantly decreased as
N rates were increased. whereas increased K rates increased fruit wt.
High rates of N produced higher numbers of green fruit and coarse
fruit, while K rates had little effect according to Reitz and Koo (4).
Reuther and Smith (5) observed that 'Valencia' orange fruit from high
K plots retained more green coloration than fruit from low K plots,
and that green coloration in high N plots was additive when high K
rates were applied. Koo and McCornack (2) found the incidence of
decay to be greater where low N rates were applied to tangerines.
Eve n where the same cultivars and rootstocks were used, data
published in previous research papers have often been conflicting.
Establishing a common reference point between previous works has
been difficult due to variability in soils. root stocks. tree age, and other
f~ctors. The authors felt this experiment was necessary to remove
some of the many variables that have existed in past investigations.
Materials and Methods
The research block was designed and planted to obtain information
on the effects of different N and K rates on Florida orange cultivars .
Leal' mineral content, tree size. and yie ld were reported in an ea rlier
paper (3), which also described the materials and methods used in this
resea rch block . Briefly, 'H aml in,' 'Pineapple.' and 'Valencia' orange
trees on rough lemon rootstock were planted at 7.62 m x 7.62 m on
Astatula f.s . (formerl y classified as Lakeland f.s.) in 1961. The 4 x 4
'Received for publication November 2, 1974. Florida Agricultural
Experiment Stations Journal Series No. 5620.
- 424.
1975.
J. Amer. Soc. Hort. Sci .
100(4):425 -428. ·
1975 .
N K factorial, replicated 4 times, was started in 1968 with fertilizer
treatments as main plots and cultivars as subplot s. Nitrogen rates
were 67, 134, 202, and 269 kg j ha per yr while K rates were 56. 112.
167, and 223 kg/ha per yr.
Samples of 40 fruit were taken at random from each plot to
determine the internal fruit quality measurements: solub le solids
(Brix}, acid, juice content. and the soluble solids/acid ratio . Samples
were collected approx I week prior to the harves t date for each
cultivar. ' Hamlin' was usuall y harvested in December, ' Pineapple' in
January-February, and 'Valencia' in May of each yea r.
At harvest time, a standard citrus pallet box, equivalent to 10
standard field boxes. containing approx 409 kg of fruit was harvested
equally from the 4 trees in each plot. This sample was washed, graded.
and sized to determine external characteristics such as fruit color.
creasing. size, and grade-lowering blemishes. An 18-kg rand om
sample was selected from each pallet , washed , waxed, and stored at
21 oc for 3 weeks at co ntrolled 85% humidity to determine types and
amounts of fruit deca y.
Statistical analyses were performed on the data where appropriate.
Significance among means was determined by Duncan's multiple
range lest.
Results and Discussion
Resu lts were summarized to show main effects of N and K on
internal and external fruit quality. This su mmation was possible
because interactions among factors under study were not significant
for most measurements. Therefore, each fa cto r can be considered
independently.
Internal quality
Soluble solids (Brix). The inlluence of N rates on soluble solids in
juice was not consistent (Table I) . During 1968 and 1969, with
relati ve ly low fruit yields. the soluble solids were lower at the high N
rates. In 1972. with a hi gh fruit yield, soluble solids were higher at
high N rates. No significant differences were found for the other 3
years when intermediate yields were obtained. Increased K rates
decreased soluble solids significantl y 5 of 6 years. Every year
significant differences existed between cultivars with ' Hamlin' having
produced the lowest soluble solids content and 'Valencia' producing
the highest except in 1970when cold temp severely damaged the fruit.
Acid. In 1969, the acid content of the juice was unaffected by Nand
K fertilization. In each of the other 5 yea rs. increased N or K, or both
produced significant increases in acid content of the juice (Table 2) .
Effects on the cultivars were inconsistent.
Soluble solids/acid ratio. Both increased N and K applications
reduced the soluble solids/a cid ratio (Table 3). The reduction due to
N was significant in all 6 yea rs. Potassium applications reduced the
425
·
1e. · an d
T a bl e 1 Effect o f N an d K on percent so 1ubl e so rd
1 s o f 'H am rm. · · p 1neapp
Treatment
kg / ha /y r
·va 1enc1a
oranges or 6-year peno d . 1968 - 73
Year
1968
1969
9.36' B
8.90 A
8.85 A
8.93 A
10.04
9.67
9.59
9.49
1970
1971
1972
1973
B
A
A
A
10.61
10.48
10.49
10.63
9.97
10.04
9.97
10.15
10.80 A
ll.OOA
ll.06A
11.31 B
10.77
10.65
10.65
10.75
B
AB
AB
A
10.62
10.68
10.51
10.35
10. 15 b
10.06 ab
10.03 a
9.89 a
11.26 B
ll.OOA
ll.OOA
10.90 A
10.75
10.69
10.66
10.73
9.23 A
9.93 B
10.94 c
10.08 A
11.07 B
11.98 c
9.29 A
10.59 B
12.24 c
N
67
134
202
269
K
56
112
167
223
Cultivar
Hamlin
Pineapple
Valencia
9.04
9.03
9.00
8.98
8.01 A
9.05 B
9.98 c
9.86
9.69
9.73
9.54
9.05 A
9.91 B
10.16C
B
B
AB
A
9.98 A
10.99 c
10.68 B
'Means separation within treatments and columns by Duncan's multiple range test at 5% (small letters) or 1% (capital letters) level of significance . Absencet
letters after mean s indicates differences are not significant.
Table 2. Effect of Nand K on percent acid of 'Hamlin.' 'Pineapple.' and ' Valencia ' oranges for 6-year period , 1968 - 73.
Treatment
kg/ha/yr
k
Year
1968
1969
1970
1971
1972
1973
N
67
134
202
269
0.59' a
0.59 a
0.61 b
0.63 c
0.64
0.65
0.65
0.65
0.69 b
0.67 a
0.69 b
0.70 b
0.68 A
0.70 B
0.72 c
0.73 c
0.72A
0.75 B
0.77 BC
0.78 c
0.77
0.77
0.78
0.79
0.60
0.61
0.60
0.6 1
0.64
0.64
0.66
0.65
0.66 A
0.69 B
0.70 B
0.69 B
0.68 A
0.70 B
0.73 c
0.72C
0.72
0.76
0.77
0.78
0.73 A
0.77 B
0.80 c
0.82 c
0.43 A
0.62 B
0.77 c
0.68 c
0.62 A
0.64 B
0.70 B
0.67 A
0.68 A
0.70 AB
0.64 A
0.78 B
0.80C
0.74 B
0.72A
K
56
112
167
223
Cultivar
Hamlin
Pineapple
Valencia
A
B
B
B
0.77 A
0.78 AB
0.79 B
'Means separation within treatments and columns by Duncan 's multiple range test at 5% (small letters) or 1% (capital letters) level of significance. Absence
letters after means indicates differences are not significant.
Table 3. Effect of Nand K on soluble so lid s/ac id ratio of ' Hamlin.' ' Pineapple.' and 'Valencia' oranges for 6-year period , 1968 - 73.
Treatment
kg/ ha /y r
1
\"
year
1968
1969
1970
1971
1972
1973
16.52'C
15 .71 B
15.06 A
14.70 A
15.70 B
15.06 A
14.92 A
14.76 A
15.53 ab
15.80 b
15.37 a
15.26 a
14.51 b
14.50 b
14.03 a
14.06 a
15.28
14.79
14.45
14.57
15.66
15.48
15 .67
15.19
15.54 c
15.18·B
14.89 AB
14.83 A
16.31 c
15.53 B
15.12 A
15 .01 A
15.06C
14.39 B
13.85 A
13.80 A
15 .73 c
14 .7 1 B
14.49AB
14 . 16A
14.72 c
13.84 B
13.41 A
13.16 A
18.89 c
14.65 B
12.96 A
13 .30 A
16.09 B
15.94 B
14.25 A
16.50 c
15.72 B
13.22 A
15.50 c
14.11 B
12.57 A
15.07 B
16.68 c
12.21 A
13.65 B
15.49 c
N
67
134
202
269
K
56
112
167
223
Cultivar
Hamlin
Pineapple
Valencia
'
B
A
A
A
13.99 b
13.84ab
13 .67 a
13.62 a
'Means separation within treatments and columns by Duncan' s multiple range test at 5% (small letters) or 1% (capital letters) level of significance. Absence
letters after means indicates differences are not significant.
ratio in the last 5 years at the I % level. 'Hamlin' had the lowest ratio
of the 3 cultivars and depending on the time of harvest. either
'Pineapple' or 'Valencia' had the highest ratio.
Juice conte/11. Increases in N rates resulted in higher juice content
426
(Table 4) in 5 of 6 yea rs. The greatest difference was between the
and 134 kg / ha per yr rates. The only significant differences relat ed
K were in 1970 when freezing temp damaged 'Valencia' fruit. Jui
content in all cultivars continued to improve as the trees becar
J. Amer. Soc. Hort. Sci.
100(4):425 - 428 .
197
-
J
""~ !"""
Table 4. Effect of N and K on %j uice' of 'Hamlin." 'Pineapple." and 'Va lencia· oranges for 6-year period. 1968- 73.
-
Year
1973
Treatment
-..,
kg/ha/yr
10.77
10.65
10.65
10.75
1968
1969
1970'
37 .8Y a
37.7 a
38.5 ab
39.2 b
50.1 A
51.6 B
52.0 B
52.2 B
44.4
45.2
45.9
47.1
38.6
38.5
37.9
38.3
51.8
5 1.6
51.6
50.8
32.0 A
40.0 B
42.9 c
52.7 c
50.6 A
51.2 B
1971
1972
1973
N
67
134
202
269
10.75
10.69
10.66
10.73
A
AB
B
B
53.3 A
55 .7 B
56.6 B
56.8 B
56.3
57.3
57.6
57.6
A
B
B
B
46.9 B
46.4 B
45.4 AB
44.0 A
55.7
55.5
56.0
55 .2
57.3
57.4
57.1
56.9
58.9
58.8
58.5
59.4
47.2 B
5 1.3 c
38.6 A
52. 1 A
55.7 B
59.0C
54.2 A
56.9 B
60.5 c
56.4 A
58.5 B
61.6C
58.4
59.0
58.9
59 . 1
K
56
112
167
223
Cultivar
Hamlin
Pineapple
Valencia
9.29 A
10.59 B
12.24 c
ignificance. Absence ,
'Percent juice by wt.
Y Means separation with in treatments and columns by Duncan's multi pie range test at 5% (small letters) or 1% (capital letters) level of significa nce. Absence of
!ellcrs after means indicates differences are not significant.
'Juice yield of 'Valencias' was reduced by mid-winter freeze.
1973
Table 5. Effect of N and K on fruit diam' of 'Ham lin ,' ' Pineapple
'Valencia' oranges for 4-year period, 1970- 73.
0.77
0.77
0.78
0.79
Treatment
kg/ha/yr
0.73 A
0.77 B
0.80 c
0.82 c
0.77 A
0.78 AB
0.79 B
56
112
167
223
C ultivar
Hamlin
Pineapple
Valencia
'"
13.99 b
13.84 ab
13.67 a
13.62 a
14.72C
13.84 B
13.41 A
13 . 16 A
1970
1971
197
1972
7.39Y A
7.57 B
7.62 B
7.62 B
7.82
7.72
7.69
7.62
B
A
A
A
7.52 c
7.24 A
7.37 B
7.32 B
7.57
7.54
7.57
7.52
7.44
7.52
7.59
7.65
7.57 A
7.72 B
7.85 c
7.69 B
7.21 A
7.39 B
7.47 c
7.50 c
7.37 A
7.57A B
7.62 AB
7.65 B
7.52 A
7.65 B
7.98 c
7.11 A
7.47 B
7.57 c
7.16 A
7.57 B
7.92 c
K
;ignificance. Absence
1973
Year
N
67
134
202
269
and
A
A
AB
B
7.21 A
7.59 B
7.85 c
Tab le 6. Effect of N and K on percent green fruit' or 'Ham lin ,' 'Pineapple,'
and 'Va lencia' oranges for 4-year period. 1970- 73.
'F ru1t dram 1n em.
Means separation within treatments and colum ns by Duncan 's multiple
range test at 5% (small letters) or 1% (capital letters) level of significance.
Absence of letters al.ter means indicates differences are not sign ifi cant.
Y
older. Fruit size may have been a factor with the larger fruit produced
at high K rates lower in juice content and the smaller fruit produced
by high N higher in juice content. 'Valencia' th e last 3 years had a
higher juice content than either 'Hamlin' or 'Pineapple.'
Treatment
kg/ha /y r
Year
1970
197 1
5.6Y A
17.3 B
22.9 c
22.7 c
3ll'.7 A
56. 1 B
60.5 B
62.3 B
14.9
28.6
31.4
29.9
13 .9
14.7
19.6
20.3
53.9
52.3
54.0
57.5
24.2
24.8
27.9
28.0
27.9
29.7
33. 1
31.3
55.1 B
75.6 c
32.5 A
20.6 A
24.8 B
33.2 c
40.0 B
24.9 A
26.6 A
1972
1973
N
67
134
202
269
A
B
B
B
· 21.0A
33.7 B
33.7 B
33.7 B
K
External Quality
Fruit size. Increases in the K rate increased fruit size eve ry year
12.21 A
since measurements started in 1970 (Table 5). Data at first suggested
13 .65 B
that increased N applications increased fruit size. but in the last 3
15.49 c
yea rs high N rates produced significantly smaller fruit. The latter
ignificance. Absence 1 yea rs were in general agreement with prior research (4. 6).
Early maturing 'Hamlin' (Nov.-Dec.) produced significantly
smaller fruit. whereas the late maturing 'Valencia' (Mar. -June) had
was between the 6" tile largest fruit. 'Pineapple,' a midse-ason fruit (Jan.-Mar.), was
lifferences related 11 Intermediate in size. There appears to be a relationship between yie ld
as reported by Reese and Koo (3) and fruit size with respect to N
applications. The first 3 yea rs' yields were low. and fruit size increased
!5- 428.
as the N rate increased. The last 3 years with relatively higher yields.
the higher N rates significa ntl y reduced fruit size.
Green {ruil. The number of green fruit not acceptable l'or fresh fruit
shipment was recorded the last 4 years (Table 6). The fruit was not
treated in ethylene degreening rooms. and in some years the high
green coun t cou ld have been reduced by treatment. The 3 higher rates
of N produced significantly more gree n fruit than the low rate in all4
years . Potassium did not significantly affect the number of green fruit
but did tend to produce sli ghtly higher percentages of green fruit asK
was increased. C ulti var differences varied from season to season and
were related to environmental factors .
Other grade lowering blemishes. Creasing is a peel disorder that
usuall y occurs in thin-skinned fruit that is mature or over mature. It
appears as sunken furr ows in the surface of the rind with no collapse
of the surface cells, but cracks or separations ca n be found in the
albedo la yer. Potassium at the lowest level produced more creasing
than the 3 higher levels (Tab le 7). Nitrogen at the 269 kg/ha per yr
J . A mer. Soc. Hort. Sci.
!00(4):425-428.
1975.
56
112
167
223
Cultivar
Hamlin
Pineapple
Valencia
A
A
B
B
12.0 B
8.5 A
30.9 c
'No. of green unmarketable fruit for fresh fruit channels divided by total fruit
in sample x 100.
Y Means separation within treatments and columns by Duncan's multiple
range test at 5% (small letters) or 1% (capital letters) level of significance.
Absence of letters after means indicates differences are not significant.
427
Table 7. Effect of N and K on grade lowering peel blemishes and decay of
'Hamlin.' ' Pineapple.' and 'Valencia' oranges for 1973-74 season.
Treatment
kg/ha/yr
% other
blemishesY
%
%
creasing
russet
0.34'
0.85 BC
0.67 B
1.05 c
5.54 b
3.36 a
2.39 a
2.83 a
1.53 B
0.56 A
0.47A
0.35 A
3.77
4.23
3.76
2.37
2.55
3.69
3.36
3.87
19.73
18.81
18 .92
17.13
0.76 B
1.42 c
0.00 A
2.62 A
2.77 A
5.20 B
3.31 B
2.42 A
4.85 c
17.70 B
31.73 c
6.50 A
%
decay
N
67
134
202
269
4.02
3.11
3.47
2.87
B
A
AB
A
25.44 B
16.52 A
15.77 A
16.85 A
cultivar were seasonal, with no single cultivar more prone to damage
Potassium has no effect on russet. Other blemishes follow the sarnt
pattern with low N producing the greatest number of blemishes.
Storage decay. Potassium did not influence the quantity of decay in
storage (Table 7). Nitrogen at 67 kg j ha per yr produced a higher level
of decay than higher N rates. but differences between the 3 higher 1';
rates were not signilicant. 'Hamlin' and 'Pineapple' produced higher
rates o f d ecay t han 'Valencia.' Data collected in previous years were
similar to those recorded for 1973. so only I year is reported.
'Means separation within treatments and columns by Duncan's multiple
range test at 5% (small letters) or I% (capital letters) level of significance. Absence of letters after means indicates differences are not significant.
YOther blemishes include wind scars, thorn pricks, stem punctures, melanose, etc.
produced the most creasing, but signilicant differences did occur at
the other rates . There was a signilicant interaction between N and K
with the greatest amount of creasing occurring where 56 kg j ha per yr
of K and 269 kg/ha per yr of N were applied. Creasing with this
treatment often was above 5%. Also, higher levels of creasing
occurred at 134 kg / ha per yr and 202 kgjha per yr of N with 56 kgjha
per yr of K. Cultivar differences were also signilicant. Creasing does
not occur every year, so only the 1973 data are shown.
Percentage of russet varied considerably from season to season due
to variability in mite populations and timing of mite control. but it has
been similar in occurrence for the last 3 years. Low N, 67 kg/ ha per
yr. recorded more russet than the 3 higher N rates . Differences by
I. Deszyck, E. J ., R. C. J. Koo, and S. V. Ting. 1958. Effect of potash on yiei
&t•
2.
3.
4
.
5.
6.
7·
8.
9.
and quality of 'Hamlin' and 'Valencia' orange. Proc. Soil and Crop Sci.
Soc. Fla. 18:129-135.
Koo. R. C. J.. and A. A. McCornack . 1965. Effects of irrigation and fertilization on production and quality of 'Dancy' tangerine. Proc . Fla . Slale
Han. Soc. 78:10- 15.
Reese, R. L., and R. C. J. Koo . 1975. Nand K fertilization effects on leaf
analysis, tree size. and yield of three major orange cultivars. J . A mer. Soc.
Hor1. Sci. 100:195 - 198.
Reitz, H. J ., and R. C. J. Koo . 1960. Effect of nitrogen and potassium
fertilization on yield , fruit quality, and leaf analysis of 'Valencia' orange.
Proc. A mer. Soc . Hor1. Sci. 75:244- 252.
Reuther, W., and P. F. Smith. 1952. Relation of nitrogen, potassium, and
magnesium to some fruit qualities of 'Valencia' orange. Proc. ·Amer. Soc.
Hor1. Sci. 59:1 - 12.
Sites, J. W., and E. J. Deszyck. 1952. Effect of varying amounts of potash
on yield and quality of 'Valencia' and 'Hamlin' oranges. Proc. Fla. S1a1e
Han. Soc. 65:92- 98.
Smith, P. F., G. K. Scudder, Jr., and G. Hrnciar. 1968. A comparison of
nitrogen sources, rates, and placement on the performance of 'Pineapple'
orange trees. Proc. Fla. Slate Hor1. Soc. 81:25-29.
Stewart, Ivan, C. D. Leonard, and l. W. Wander. 1961. Comparison of
nitrogen rates and sources of 'Pineapple' oranges. Proc. Fla. Stale Hor1.
Soc. 74:75-79.
- - - , and T. A. Wheaton. 1965. A nitrogen source and rate study on
'Valencia' oranges. Proc . Fla. Sw1e Hurl. Soc. 78:21 26.
Abstract. Thiocyanate ion (SCN - ) content was determined in root and foliage of 'Burpee White' and 'French
Breakfast' radishes (Raphanus sativus L.) grown hydroponically in modilied Hoagland's solution at
2 concentrations ( 1h x and 2x) and sulfate at 3 levels (I , 4, and 8 meq/liter). Root and foliage of both cultivars
grown in 1h x solution contained more SCN - than tissues from plants grown in 2x solution. Although SeN content of 'Burpee White' roots increased linearly with sulfate level in 1 1 x solution, SCN- content in
corresponding 'French Breakfast' roots and in roots of both cultivars grown in 2 x solution was not signilicantly
affected by sulfur nutrition. Nutrient concentration altered the synthesis or accumulation of thiocyanate-yielding
compounds without affecting growth. Results indicate that the enforcement of regulations governing permissable
amounts of toxicants, such as SCN-, in new cultivars may be difficult because of genotype-nutrient interaction
which can induce variability in toxicant content.
evolved a mechanism for
which serve as protective
toxic metabolites, such as
oils), and thiooxalidones.
formed by enzymic hydrolysis of non-toxic glucosinolates (thioglucosides) when cells are ruptured (7. 9) also are responsible for the
characteristic flavor and pungency of cruciferous plants (8. 26).
Many studies have related goiterogenic toxicity of cruciferou
Received for publication November 4. 1974. Paper presented in part at the
7lst Annual Meeting Amer. Soc. Hort. Sci. in conjunction with the Can. Soc.
Hort. Sci., Aug. 1974.
'Department of Horticulture. Macdonald College.
3
Research Scientist (formerly Research Associate), present address: Ornamentals Research Service. Central Experimental Farm, Ag •culture Canada.
f
Ottawa. Ontario.
428
25
ph
Literature Cited
B. Bible 2 and Calvin Chong 3
Faculty of Agriculture of McGill University, Quebec, Canada
1
Pa
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Content of Thiocyanate Goiterogen in Radishes as Related to
Nutrient Concentration and Sulfur Nutrition 1
Plants of the Cruciferae family have
producing sulfur-containing metabolites
agents against predators ( 15, 27). These
thiocyanates. isothiocyanates (mustard
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J. Amer. Soc. Hart. Sci.
100(4):428 - 431.
1975.
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