Group Title: Mimeo Report - Belle Glade, Florida Agricultural Research and Education Center ; BG-71-6
Title: Leafy vegetable variety preference of aphids and a promising new compound for aphid control
CITATION THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00067605/00001
 Material Information
Title: Leafy vegetable variety preference of aphids and a promising new compound for aphid control
Series Title: Agricultural Research and Education Center Mimeo Report
Physical Description: 3 leaves : ; 29 cm.
Language: English
Creator: Janes, M. J
Everglades Experiment Station
Publisher: Agricultural Research and Education Center
Place of Publication: Belle Glade Fla
Publication Date: 1971
 Subjects
Subject: Greens, Edible -- Varieties -- Florida   ( lcsh )
Aphididae -- Control -- Florida   ( lcsh )
Genre: non-fiction   ( marcgt )
 Notes
Statement of Responsibility: M. J. Janes.
General Note: "April 1971."
General Note: Caption title.
Funding: Belle Glade AREC mimeo report ;
 Record Information
Bibliographic ID: UF00067605
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 65653064

Full Text




E /- AGRICULTURAL RESEARCH AND EDUCATION CENTER MIMEO REPORT BG-71-6


April 1971
April 1971


LEAFY VEGETABLE VARIETY PREFERENCE OF APHIDS
AND A PROMISING NEW COMPOUND FOR APHID CONTROL

M. J. JANES


During the winter of 1970-71 a test was conducted on leafy vegetables to
determine the insect control efficiency of two insecticides and obtain residue
data. Five leafy vegetables, head lettuce (Great Lakes), leaf lettuce (Bibb),
Chinese cabbage (Chihili), endive (Green curled ruffec), and romaine Valmaine)
were grown and sprayed with two insecticides, Orthene(Q, and Phosvel P, both
experimental compounds as yet without use labels.

Methods

The 5 crops were planted in a latin square and the plots were 4 rows 25 feet
long with 3 feet between rows. The plots in tier A were untreated checks, tier
B was sprayed with Orthene at 1 lb. AI/acre, tier C, 2 Ibs. Orthene, tier D,
1 lb. Phosvel, and tier E, 2 Ibs. Phosvel. These tiers were separated by a 9-
foot alleyway. Sprays were applied in 100 gallons of water/acre at 200-250 psi
with a spray boom on a power sprayer. The crops were planted by direct seeding
on October 15, 1970. Six sprays were applied at weekly intervals on November 9,
16, 23, 30, December 7 and 14.


Results and Discussion


Insect Control. The only general infestation was by adults of the banded
cucumiber-ieetle, Diabrotica balteata LeConte. The land had been flooded prior
to planting, an effective means of controlling insect larvae developing in the
soil. The beetles would scarcely have had time to develop on the newly planted
leafy vegetables but migrated into the fields. The infestation of beetles on
the different varieties of plants should therefore be considered essentially the
same as if they were on a single crop. The number of adult beetles on 50 plants
in each plot on November 11 are shown in Table 1. The damage in the checks was
heavy because the plants were still very small.


Table 1. Numbers of adult banded cucumber beetles
initial treatment.


observed two days after


Treatment
Treatment Untreated Orthene Phosvel
Rate, lb. AI/acre Check 1 2 1 2

Head lettuce 28 1 0 1 0

Leaf lettuce 15 1 HUiE LIBRAR1 0

Chinese cabbage 8 0 0 1 0
AUG 31 1971
Endive 6 0 0 0 0

Romaine 9 h.F.A.. Univ. of FloBda o












The infestation of loopers was low throughout the test period with the high-
est numbers present on November 11. On that date, there was about 1 per 5
plants in the checks with none being found in the treated plots. Two species of
loopers were present, Trichoplusia ni (Hubner) (the cabbage looper), and
Argyrogramma verruca (Fabricuius). In previous seasons the cabbage looper has
been by far the most abundant looper on head lettuce.

Two species of aphids were very abundant on Chinese cabbage and most of the
plants in the check plot were killed. The green peach aphid Myzus persicae
(Sulzer), was more abundant at first but later the turnip aphid Hyadaphis pseudo-
brassicae (Davis) became the more abundant species. The turnip aphid is usually
conf-ined mainly to cruciferous plants and it was not too surprising that the
varieties other than Chinese cabbage were essentially free of this insect. The
green peach aphid also was confined to the Chinese cabbage although the insect
normally has a wide host range, and may occur in destructive numbers on the other
crops. Aphid counts made November 24, and December 4 are shown in Table 2. The
first figure shows the average number of aphids per square inch of under leaf
on 10 plants. The figure in parentheses shows the estimated number of aphids per
average sized leaf. It may be noted that Orthene was completely effective against
both species of aphids, while Phosvel was only partially effective showing how-
ever a higher degree of control of the turnip aphid than of the other species.

Table 2. Aphid counts on Chinese cabbage

Treatment
Untreated Orthene Phosvel
Rate Ib AI/acre check 1 2 1 2

Green peach aphid
November 24 130(2600) 0 0 108(2160) 73(1460)
December 4 23(575) 0 0 16(400) 12(300)
Turnip aphid
November 24 32(640) 0 0 4(80) 3(60)
December 4 155(3875) 0 0 9(225) 7(175)


An unexpected and interesting occurrence was that aphid populations were so
heavy on the untreated Chinese cabbage that the crop was almost completely des-
troyed while at the same time aphids were essentially absent from the other four
leafy vegetable crops. Further studies will be made to determine if Chinese
cabbage can be interplanted with other leafy vegetables to serve as a trap crop
to prevent aphid population build-up. It is known that light traps, which draw
insects into an area from a considerable distance, have not proved very effective
since they cause the general area to become restocked. However trap crops have
been successful in some cases.













Residue Determinations. Residue levels are being determined at the
Pesticide Research Laboratory, University of Florida, on samples taken during
December and January. It is customary in these determinations to use the standard
rate and double the standard rate of insecticide, for this reason the two-pound
rate was used in these tests.

Summary

Five leafy vegetables, head lettuce, leaf lettuce, Chinese cabbage, endive,
and romaine, were grown to determine effectiveness of Orthene and Phosvel for
insect control. Orthene applied at the rate of 1 or 2 pounds per acre was very
effective in controlling green peach aphid and turnip aphid. Phosvel was less
effective against these aphids. Of particular interest was the fact that aphid
population on untreated Chinese cabbage was so heavy the crop was almost com-
pletely destroyed while very few aphids affected the other leafy crops. Further
studies will be conducted to explore the possibility of interplanting Chinese
cabbage to serve as a trap crop to prevent aphid build-up in other leaf crops.
Both insecticides gave good control of light infestations of loopers and banded
cucumber beetles.



























BG-71-6


500 Copies




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs