xt73xs5jbt8c https://exploreuk.uky.edu/dips/xt73xs5jbt8c/data/mets.xml   Kentucky Agricultural Experiment Station. 1953 journals 012 English Lexington : Agricultural Experiment Station, University of Kentucky Contact the Special Collections Research Center for information regarding rights and use of this collection. Kentucky Agricultural Experiment Station Progress report (Kentucky Agricultural Experiment Station) n.12 text Progress report (Kentucky Agricultural Experiment Station) n.12 1953 2014 true xt73xs5jbt8c section xt73xs5jbt8c  / V _
Progress Report 12 May,. 1953
SOIL TREATMENT FOR CORN ROOTWORM CONTROL
By J. G. Rodriguez  I
Corn rootworms have occurred in Kentucky in sucbsian unpre#
dictable manner that the control problem has been difficult to approach.
Observations incpast years have shown that the most frequently attacked »
areas occur on bottomlands. Infestations occur on upland corn—growing
areas less frequently; in 1950, however, infestations of the Southern
corn rootworm were widespread over many upland fields and much re-
planting had to be done as a result of heavy damage, or total loss of first ·
plantings.
Investigations in progress since 1950 have been directed to- ·
wards control of Southern corn rootworms by means of soil insecticide
spray applications. During this time only two experiments have been
located on siiies where rootworms have occurred. Because these infesta-
tions cannot Abe predicted, a thorough evaluation of insecticide toxicity
on Southern corn rootworms has not been made. Nevertheless, it has
been possible to study the effect of certain chlorinated hydrocarbons, as
_ soil insecticides, on the corn plant as they have affected growth and yield.
This progress report is a summation of the work up to the present time.
1950 TESTS
The results of a test conducted near Bardwell, Kentucky on
Mississippi River bottom land are shown on Table 1. Six acres of a
field planted to Kentucky 203 were sectioned into plots which were . _
arranged in randomized blocks; the insecticides were applied in bands
over the planted row with a tractor mounted weed—type spray boom 3 days
after the corn was planted. The Southern corn rootworm infestation was
relatively light. Under these conditions aldrin gave somewhat better
protection than all other materials; it produced the highest yield, 76.5
bushels per acre, as compared to 60., 1 for the check plots. Aldrin and
. chlordane harvest yields were significantly higher than the yields of
dieldrin and the untreated check.
I l
2
j   This work was aided by a grant made by the Julius Hyman and
V _ Company Division of the Shell Chemical Corporation
S  -
Kentucky Agricultural Experiment Station
University of Kentucky
Lexington

 -2 -,
Another experiment was located in Jessamine county where an
infestation of Southern corr rootworm was found damaging about two-
thirds of the young plants in a 4 acre field of up-land corn. Corn (Ky. 103)
was replanted over the original row and 4 days later, treatments were y
applied broadcast using a tractor -mou;nted weed spray boom. Injured
plants in the replanted row vvere counted and height measurements were
also takenrthis com was cut for guage on Se*pterri‘kser`.5..¤ fResu.1ts`are" ·
summarized in Table 2.. Less rootworm injury occurred in the aldrin-
treated plots; furthermore, plant measurement records showed these .
plots averaging 5.2 inches taller plants than the untreated check. The BHC
treated plots produced the most silage. however. - J
1951 TESTS _
The results of a test conducted in a farm near Lexington are   .
shown on Table 3. Four and one-half acres of a field were arranged in
randomized plots and band applications of various soil insecticides were
made with a weed spray boom at pre-emergence. Rootworm infestations ‘
failed to develop in this field, as well as in other tests in 1951; however, _ _
plant measurements made 6 weeks after planting showed that dieldrin and .
chlordane treated plots averaged 3.15 and 3. 2, inches taller respectively, ‘
than the untreated plots. Drought conditions later in the year caused large
yield variances and none of the treattnents were significantly different than
the check. _
Two small-plot tests planted to Ky. 103 were located in the station
farm; in one test materials were applied at pre—emergence in 12-inch bands
and in another te st aldrin was applied broadcast and in bands at planting
time, at pre-emergence, and at post—emergen.ce. The results in the first
test (Table 4) showed that chlordane applied at O. 86 pound per acre was - _
significantly different than the other treatments; chlordane. pl0ts~pr0duced`
78 bushels per acre as compared to 59 for the untreated check. The results
in the second test (Table 5) showed that differences in yield between the .
broadcast and the band treatments were not statistically significant; aldrin
applied broadcast at 3 pounds per acre at post-emergence, however, was
significantly different than the untreated check; the yields were 74. 4 and
63.2 bushels per acre respectively. In both tests, amine 2., 4-D was used 3
as a pre—emergence spray, applied in combination with insecticides when- l
ever the insecticide treatment was to have been applied at pre-emergence.
1952 rssrs  
The work conducted during 1952 involved one small plot test at the   .
Station Farm and three large plot tests elsewhere in Fayette county; one
other large plot test was located in Ballard county on Ohio River bottom
land. None of the test sites developed corn rootworm infestations. (
The results for the test located on the Sta.tion Farm are given on
Table 6. Aldrin applied at the irate of l pound per acre in a band at plant-
ing produced 13 bushels more grain per acre than the untreated check, a
highly significant difference, the BHC treatment was also highly significantly
` different from the untreated check.
The chlordane treatment was significantly different than the untreated
check, producing 10 bushels more per acre. The hybrid was Ky. 103.

 -3-
Two adjacent fields of seed corn (WF9 x 38 — 11) were treated with
a sprayer-equipped planter in Fayette county and the results of the test
are given in Table 7, The yields represent total harvest of U. S., 13
  seed corn from these fields. ‘
The results of the remaining tests are not shown; although plant ( .
measurements taken in the early part of the season were comparable
to the differences found in the tests given in Tables 6 and 7, the yield
differences at harvest were not significant. This is attributed to extremle
l variations brought upon by the drought in the areas where the tests were
located,.
DISCUSSION OF RESULTS
The work done in Bardwellin 1950 indicated that substantialiin-
_ creases in corn yields could be effected with soil insecticide application;
J only 5 percent of the untreated plants showed bud injury in this experi-'
( ment (Table l)u When l0 percent of the plants showed bud injury, silage
yields were increased up to 3.,4 tons over the untreated check (Table Z);
although comparatively heavy dosages of materials were used in this
g test, these applications were made broadcast and a comparable dosage
` ( as a band application would have reduced the dosage to 1/3 or l/4 of
the material used.,
It is recognized that bud injury on the plant may result only when
the rootworm larvae penetrate the crown of the seedling plant and the
effects of root feeding or root pruning on plants past the seedling stage
by this same insect or other insects may not be obvious on the top part
of the plant., Thorough and extensive examination of roots could not be
” made. However, in order to detect effects on influences on the plant,
measurements of the extended height of the foliage were used as a crite-
rion. These plant measurement data established the fact that a favor-
able conditioni was induced by the application of chlorinated hydrocarbons
(Tables 2-7)¤ The plants responded in increased top growth to applica--
tion of aldrin, dieldrin, chlordane, heptachlor, and BHC. Measurements
taken 4to 6 weeks after planting, showed more than 5 inches growth
_ over the untreated plants; although measurements were not taken at
harvest, observations made at that time generally showed that the
treated plots were easily distinguishable from the untreated check plots.
Some indication of this may be gotten from the data presented on silage
I and fodder on Tables Z and 6,
Increased harvest yields were also obtained (Tables 1, 3-7). It is
not understood why some materials showed superiority over others in
one instance and in another instance the reverse was true (Tables
‘ 1, 4, 6, 7); nevertheless, the data show that aldrin and chlordane were
consistently more effective than the other materialsu
The phenomena involved in inducing favorable plant responses and
yields are not completely understood but the following factors or combina-
tion of factors may be responsiblei

 -4-
1 - Elimination orreduction of common root feeding insects (root-
worms, wireworms, grubs, aphids,cutworms).
Z — Elimination or reduction of less important root feeding microfauna
(springtails, symphilids, millipedes). y   ‘
3 — Effects of above factors or introduction or dissemination of i
pathogenic agents (rots,di`seases). ‘
4 — Direct effects of soil insecticides on soil microorganisms.
5 — Direct physiological effects on the plant system.
CONCLUSIONS 1 » r
Certain conclusions can be reached from the worlcthus far: T “
1 - Soil treatment effected a uniform stand. V
2 - Favorable effects on plant development were obtained. Aldrin _ . .
increased plant growth an average of 5. Z inches in one test. .
Silage yields were significantly higher in the treated plots than
in the untreated check plots in this test. i ‘
3 - Significant increases in harvest yields of grain were obtained
with aldrin or chlordane treatment. A carefully designed experi-
ment in the Station Farm in 1952 produced an increase of 13
bushels in the aldrin treated plotrs(’(-1pound'ipe'r acre); over the
untreated check plots, in spite of the fact that no visible corn
rootworm infestation occurred. `
4 — One pound of aldrin or chlordane per acre, applied in a band ,
during planting, effectively reduces Southern corn rootworm:
and it is likely that many other insect species are reduced or
eliminated.

 Table 1.. Coma Rooiwosm. CC>?1T‘LTT’C»1._. 1950 €YT.,A. Bishcp Fawn, Barsdwcli,.
MWQR ` r¤_mm¤__ "__m___‘_ Ks HRC c k  
Treaimssmf 1 Dosage   Pswcani lpjuxad 3 Ymld. 4
_ (vs. /A.) _ 1¤1s».1 (A- —,»· ..   (Bu. /A.) -
1BHC 4-»T"Tl“Z`:`"”"”"“;Z` ""”"' 1.0 ` ’ 71. 6 "`
2C?:.1c>x·;1a12a——-· 4 1.1 73.8 l
3A1d.z·i·r; ---1--- is 0.15 76.5
4 Dia1<1x1r; ————-1 - 4 O. Es 62.. 8
5 T0xaph1¤a·a:1s·~-— - 4  ., 1. SE'. Z
(>Cb..ec1<.—-v-·—-~--—- 5..0 60.1
L. S, D,.   P€§£T’(F€Z;`L·*"‘ ·--— ~·——~~-—-~——--- - 10.4 V
L. S., D. ., 1p¤ar;·c·smi·———·=·—-—=—~—·~—·~·~~—·--=-— 14a 4
1/ 1\/Ia*:s;~:r;i.a1s appheci IO plots rep1i.cai;s.p1ecs ‘;aP;.s2.~ af ;:`a·;;n10m ixmrn each plot; each
— sa.;m.p1s,, 2.5 fac": of ;r»c.·w.. Yield   as sEt;s;11»2d. gxlairrr. at 15 1/2%
rxmzsscuxs.
Tabler Li. —- C0:r·. .R¢;m;w·:¢.r‘r*·— Cc:¤‘..r·0E, 19*513 {Snr iz ··‘¤ QF Wes? Faxfrm, .I6:ssam:.z1c
l C·;L·:.m.j-, , Kamfuckry}
‘I‘;re:a.·?zme¤.*, 1 Dcssags   Pew.v<;~-·r;-..1*1_j&1.;eAd 3 PE.aw4 Szlage 5
{Tr; 9 {A] P1'.&Y1é.ZS {Av.   Hvi gb.? (lb., /A. )
V Hmmm {   N Y ‘ (Av incies}
1 BHC —»?YmYTY”Y”? T"` ’``` `"L*""`9`" " ""”`"”"`"`"Z‘?"‘? ``”" ""' ” `1 ”` 9?*2"T`§. ""”"?’IT€`6`?
.?Z·C‘p.1c¢:··iia;;e — — —— .5 ,,17 gggn c; 199 780
3 A1.=5..r·i.w:.— — —~ —-     5 1. #5+ .4 [3 C 19, 243
4_D1.€1.#j1l'”}f`.·r ~~·  7»   1 .3.3. fw 19, 534
5 1`0xap§ii.e.r=.¢.~     5 Z5 L1. 8 19.. 015
?>C11-ac1~1——-   15.0 19   14,915 ’
L S., D. `;=    ~·—- Y  —·~———-—»·-· WEB/1
' L. S. D L pe r*<.~¤r·&-·-1····   · V     796
  Ma‘¥.·zT·"1¤.1.s apphcq TO plms t¤s;.·1;.r.1a -..1 1i— ¢:1i·’e.: E5` war ¤r phy 14- fuws wxris
— and  .31 f-2~-* lamgg, M p.··es—¤1r‘»·»· ¤.<.  mi 7;.:.1 1 5
  App11r.a‘1e·¤r.·.'t ··1cari.c·a;-‘ a· 15 Bla;}-;*',F"".£     T`“`Z1>C'L’..' ~ pw acxr.
37 Coax.? r!aari.—·   BU 0% ;»1a.~v·s sf.·.c;=¤-irq F   ;’<}‘.¤. 7
;1`/ M¤;a#· Gx‘~ ·1i¤;.~<;  vg? ··v_ -· .1 WO piarifs p· r   .;.¢zir;=.r*_· - c:··· H1? , 3
1   CQI`f.p`.».¥.ii1 11*/ Sa1'.‘,_’,;-'i;~‘·1;?. ·:';;pi’v,.x‘.71"~,ai· 1;; 41*070 gi FQ; M‘·‘.31  in *,;.9,5,
— ‘·M<·xg1;&-C..

 -6- 2 v_
Table 3. - Corn Rootworm Control, 1951 (S. J. StokesZFarm, Lexington,
Kentucky)
Treatment 1 Dosage 2 Plant Height 3 Yield _
(lb. /A.) (Av. inches) (Bu. /A)
1 BHC —-—--—— — 1 44. 4 ‘ 59. 6 '
2 Dieldrin ———-— - 1 46. 9 61. 0 .
3 Chlordane —-—- 2 46. 6 68. 2
4Aldrin --————— Z 44. 2 61. 4
5 Heptachlor--- _ 2 44. 0 62. 4 E
6Check -—--—-- _ 43.4 60.6 ,
L. S. D. , 5 percent --—-— 2.4 10.2
 
1/ Materials applied to plots replicated 5 times, each plot 12 rows by 167 . 
feet, at pre-emergence on June 1. 1
2/ Application made in 20—inch bands at 6 gallons of spray mixture per acre.
3/ Mean extended height — 250 plants per treatment - on July 6. _
4/ Fifty feet of double row harvested from each plot; yield as shelled grain
at 15 1/2%. moisture. —
Table 4. — Corn Rootworm Control, 1951 (Station Farm, Lexington, Kentucky)
 
Treatment 1 Dosage 2 Plant Height 3 Yield4
(lb./A.) (Av. inches) (Bu./A.)
 
1BHC—·— -———- - 3 44. 8 66. 3
2 Chlordane ——-- 3 42. 9 78. 0 ’ A
3 Dieldrin ———— — 2 45. 3 64. 1
4A1drin —-——--- 3 44. 5 62. 1
5 Heptach1or——— 2 44. 5 59. 2
écheck -—--—- — 42.5 59.0
L. S. D. , 5 percent —-—- 2. 5 12. 0
L. S. D., 1 percent ——·- 16. 3
 
1/ Materials applied to plots replicated 5 times, each plot 4 rows by 35
feet, at pre-emergence on May 30.
2/ Application made in 12-inch bands at 6 gallons of spray mixture per acre.
3/ Mean extended height — 250 plants per treatment - on July 5.
4/ Thirty—five feet of double row harvested on October 29; yield as shelled
grain at 15 l/2% moisture.

 : _’?_
Table 5. - Corn Rootworm Control, 1951 (Station Farm, Lexington,
Kentucky) (
Aldrin Treatment Dosage 2 Plant Height Yiéld 4 =
(1b./A.,) (Av. inches) (Bu./A.)
 
Bands y
1 At planting-—·-== =--- 0.. 86 43.8 65.9
2. At pre—emergence—— ` 0. 86 44. 8 66. 8
3 At post—emergence-—- A 0. 86 46. 2 66. 0 '
Broadcast
4At planting — -~~~— — 3.0 43.7 71.2
5 At pre-emergence—- 3. O 44. 6 71. 2
6 At post—emergence—- 3. 0 44. 5 74. 4
·‘? C·hesk-——~·~·~—~»~—-—- 42.2 63.2
L. S. D. , 5 percent --——~~ 2. 9 8. 9
 
1/ Aldrin applied to plots replicated 5 times, each plot 4 rows by 35 feet,
‘ on May 26 (planting). May 30 (Pre-emergenfieélgand June 5 (emergence).
2/ Application made in 12—inch bands at 12 gallons of spray mixtmeeper acre.
3/ Mean extended height — 250 plants per treatznent ~ on July 5.
4,/ Thirty—five feet of double row harvested on October 29; yield as shelled
grain at 15 1/2% moisture.
Table 6. — Corn Rootworm Control, 1952 (Station Farm, Lexington.
Kentucky) . g
Treatment and 1 Plant Height (Inches) Z Yield Fodder Wt. 4
Dosage (1 1b. /A.) 5 wks. 6 wks. (Bu. /A) (lbs. /A)____
1 Aldrin·-=·-—~ ——— 30.2 48.6 99.9 9232
2 Chlordane-—·=— - 28.4 45..9 96.9 8930
3 Heptachlor ———- — 30. 0 46. 5 92. 4 9807
4 Dieldrin -—-»--- — 28. 7 47. 2 94. 4 9505
· 5 BHC--——~··=-»—~——-· 30.4 49.4 98.8 9769
6 Cb.eck——·~·~—·¤——-»- 26.9 44.4 86.,9 8874
L. S. D. , 5 percent—~···»·~~·-·—- 8.5
L. S. D., 1 percent——·~l-———— _1l.6
1/ .M¤~l3€I`l(¥i·l5 applied to plots replicated 5 tirnes each plot 4 rows by 33 feet,
at planting, May 17. Application made; in 12-inch bands at 7 gallons
of spray mixture per acre.
2/ Mean extended height — 250 plants per treatment - 5 and 6 weeks after planting.
`   Harvest Octoberll  yieldas shelled g·:~a.§.net 15 1/2% moisture.
4/ Field weight.

 -8-
Table 7. — Corn Rootworm Control, 1952 (David Prewitt Farm, Lexington, 1
Kentucky)
__ __ _ Field 1 I J Field 2
Treatment and Plant Height 2 Yield 3 Plant Height Z Yield 3
1
Dosage (1 1/2 11../A.) Av. In.) (Bu./A.) (Av. In.) (Bu./A.)
1 Chlordane -—=- —=— - 27. 0 78. 5 26. 8 68. 9 i
2 Aldrin ————--—-— — 27.4 70.0 25.5 63.5 »
3 Heptachlor--- —-— 26.4 66.4 24.8 61.7
4Check -——------ —— 23.3 67.7 25.6 59.8
l_/ Materials .app1ied in bands with planter—sprayer - June 1, using 5 gallons
of spray mixture per acre. .
2/ One—hundred plants measured — extended height — 3 weeks after planting.
3/ Computed on total harvest of U. S. 13 seed corn harvested — 2 plots 5
(replicates) each 0. 636 acre on Field l and 0. 549 acre on Field 2; 1 plot .
on untreated check in each field.