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EE5 2'-F
Everglades Station Mimeo Report EES::70-g
EFFECT OF RATES OF ALAR ON GROWTH AND YIELDS OF CARROTS
V.L. Guzman
April, 1970
Exp. 582
Objective:
The objective of experiment 582 was to reduce top'growth, thus
facilitating harvest.
Location: Duda Farm, Belle Glade, Florida.
Soil type: Peaty muck six years under cultivation.
Soil test after fertilization: pH = 7.00; P = 40;,.K= 400 lbs/A.
Design: Randomized blocks with eight replications.
Herbicide: Lorox and mineral spirits.
Seeding date: October 25, 1968.
HUME LIBRARY
IHUML BRAR!
Alar treatment date: December 20, 1968 SEP 1 1972
Spray rate: Drip point.
Stage at Alar application: 6-9 leaf stade;, g A6S f d,
Weather: 70 degree F; no rainfall; soil"moisture good.
Treatments Alar ppm: 1 = 0; 2 = 1000; 3 = 2000; 4 = 4000.
Harvest date: March 7, 1969.
Harvest plot: 10' x 45" double rows, total area 10' x 45" = 37.5 sq. ft. plot.
Results: There was a reduction in top growth noticeable to the eye two
weeks after application. This reduction appeared to be in proportion to the
concentration of Alar used. However, reduction of top growth had
disappeared at harvest. Yield and quality of the roots are given in Table I.
It was an added bonus to find that yields were increased with Alar.
Single degree of freedom analysis indicated that Alar (rates) significantly
increased yield over the check. There were no significant differences
between the Alar rates, but all the Alar treatments combined resulted
in yield increase over the check. No difference in root quality was
found among the treatments.
I
2
Table I. Mean effect of Alar rates on yield and quality of carrots,
applied 50 days from seeding (Exp. 582).
Roots
Total Dia- Inside
Alar Total U.S. No. 1 U.S. Jumbo Marketable Length meter color Cull
ppm Lbs. Lbs. No. Lbs. No. Lbs. Tons/A (in) (in) 1/ Lbs.
0 53.9 32.3 2.5 5 34.8 20.2 6.6 1.1 4 18.5
1000 57.5 35.7 2.9 5 38.6 22.4 '6.8 1.2 4 18.2
2000 56.1 34.1 4.1 7 38.2 22.2 6.5 1.2 4 17.1
4000 59.4 36.8 3.7 6 40.5 23.5 6.5 1.2 4 18.8
Significance at 5%
1/ 1 = poor to 5 = excellent.
Exp. 582a and 582b.
Objective: It is known that the effect of Alar is dependent on the stage of
growth at which it is applied. Therefore, the objective of these tests
was to find the effect of rates of Alar when applied at two stages of
growth of the carrots.
Exp. 582a
Location: Duda Farm, Belle Glade, Florida.
Soil type: Peaty muck six years under cultivation
Soil test after fertilization: pH = 7.00; P = 23 and K = 199 Ibs/A.
Design: Latin squares 4 x 4.
Herbicide: Lorox and mineral spirits.
Seeding date: November 15, 1968.
Alar treatment date: January 7, 1969.
Spray rate: Drip point
Stage at Alar treatment: Size of tops 8" 9". Size of roots slightly
less than 1/4 inch.in diameter. Eight leaves per plant at time of
application.
Weather: 67 degree F; clear; soil moisture good.
Treatment Alar ppm: 1 = 0, 2 = 1000, 3 = 2000, 4 = 4000.
Harvest date: March 12, 1969.
Harvest Plot: 10' x 45" = 37.5 sq. ft.
Exp. 582b
Location: Duda Farm, Belle Glade, Florida.
Soil type: Peaty muck six years under cultivation.
Soil test after fertilization: pH = 7.00; P = 10; K = 199 lbs/A.
Design: Randomized blocks with eight replications.
Herbicide: Lorox and mineral spirits.
Seeding date: December 9, 1968.
Alar treatment date: January 7, 1969.
Spray rate: Drip point.
Stage at Alar treatment: Length of tops 1"; length of roots 1"
and very slender (width of a pencil lead). Four leaves at timo of application.
Weather: 67 degree F; clear; soil moisture good.
Treatments Alar ppm: 1 = 0; 2 = 1000; 3 = 2000; 4 = 4000.
Harvest date: April 11, 1969.
Harvest plot: 10' x 45" = 37.5 sq. ft.
Results of experiments 582a and 582b: The effect of Alar was manifested
a few weeks after treatment. Again there was a reduction in top growth
proportional to the rates employed. This reduction was not noticeable at
harvest, as indicated in Table III.
Effect of Alar on yield was dependent on the growth stage of the
plants, Tables II and III. In exp. 582a there was a significant yield
increase only when the 4000 ppm of Alar was compared to the check. In
experiment 582b, their was no yield increase. Yield increase appeared to
have no dependence on root length or diameter, but rather on greater
number of marketable roots in the Alar treated plots. It is possible
that most of the growth retardant spray fell on the heavy foliage of the
most vigorous plants resulting in stunted top growth of these plants.
Whereas the small plants underneath were protected from the spray by the
larger plants and continued to grow and produces roots of marketable size.
In exp._582b the application of Alar was made at very early stages of
growth. No treatment effect was found on root quality.
These preliminary results seem to indicate that response of carrot
yields is to a large extent dependent on rates and time of application. It
appears that early application is of no benefit, whereas applications made
at later growth stages increase yields.
It is possible that higher rates applied at later stages may further
increase yields.
Table II. Mean effect of Alar rates applied 53 days from seeding on
yield and quality of carrot roots. (Exp.. 582.a)
R+ r- C + t i*
Total
Total U.S. No. 1 U.S. Jumbo Marketable Length
Lbs. Lbs. No. Lbs. No. Lbs. Tons/A (in)
Dia- Inside
meter Color
(in) 1/
0
1000
2000
4000
Significance
38.1 28.2
38.9 27.4
41.5 30.0
42.0 30.6
at 5%
2.8
3.4
3.2
.2.7
.31.0.
30.8
33.2
33.3
18.0 7.5 1.1
17.9 7.4 1.1
.19.3 7.3 1.1
19.3 7.3 1.2
4 7.0
4 7.5
4 7.4
5 ,. 7.9
1/ 1 = poor to 5 = excellent.
Alar
ppm
Cull
Lbs.
i,
Table III. Mean effect of Alar rates applied 18 days from seeding on
roots. (Exp. 582b)
Total
yield
Roots
Dia-
and quality of carrot
Inside
Alar Total Total U.S. No. 1 U.S. Jumbo Marketable Length meter Color C
pm Lbs. No. Lbs. No. Lbs. No. Lbs. Tons/A (in) (in) 1/ L
0 34.3 299 24.3 164 0.7 2 25.0 14.5 7.7 1.0 4 8
1000 34.3 308 24.2 185 1.6 4 25.8 15.0 7.6 1.0 4 8
2000 34.1 309 24.4 169 1.2 2 25.6 14.9 7.5 1.0 4 8
4000 34.1 302 25.6 177 1.0 2 26.6 15.4 7.6 1.0 4 7
Significance at 5% N.S. N.S.
1/ 1 = poor to 5 = excellent
This preliminary report was presented to the muckland research workers conference at Montreal,
Canada, July, 1969.
ull
bs.
.8
.4
.4
.4
Tops
Lbs.
25.6
25.7
25.5
25.2
N.S.
EES 70-8
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