Insecticide formulations, application rates spraying
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methods, amounts of water used are checked to explain
tobacco leaf injury and effects of bud burning _
Spray Damage to Tobacco Plants ,,
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BY Rl(}l’lARl) THURSTON out of the leaf (Fig. 1). In eases of heavy leaf burn- _
I)¢·pur!rn1·n! of Iinloznology and Botany . . T . . "*
I_ l_ l_ t_ f _ t, _1 t t It b mg notlnng but the mid-vein and some of the lateral
_ l Otltu ·‘1’1’_‘S*‘l"‘;5l2 "?S°_° lflf Q g°-01180 Ov f¥§O veins were left. The plants recovered, however, from »··
"NT 5 'lmy lylmif 0 M7? m A Tun} il 0* Wayh G this type of injury and except for the loss of leaf tis- Q ‘
< · x .> Y ‘ ' ‘ · T 'Y
1"_"{“°t""‘ O mn Ofmu °mCb )y _ 0 mge flcatmfmti sue no observable damage was done except possibly
of hudane and chlordanc was described in a prevrous www Slight gtlmtmg of the Ppmtg Q
iutielt in Kt.utpel\}y Faim and Homc Science. l'l;hcse The effects Ot bu(l bummg (hd not ShOW up SO ;. p
l()llI]();l(¥·f}i]_)(* ela symptomsl were lnot bcausee, row- rapidly but Wwe more drastic in the long mu, If dw
  W tr Of uf Common y USM to MCO mS€°fl` bud was killed, a stunted plant with many suckers ·
" _ _ _ was produced. Often only part of the bud was killed, _
FO ~ ‘·   p. gl:  `.  ·..e;"  
matic naphtha solvents, but there was no difference in   :,_ ` _V‘’‘‘’ V   ---/».c, q:=·  yi  :,·· ;t.·    . A   ,;_
- . . F¤‘i‘=¤*"‘     V ·   ¥ " `
the amount of bud burmng. Holding thc sprayer *    
nozzle 4 inches from the plant resulted in much more   T   TT     x
. _   ,  f T » ( r r·_,_     
leaf and bud burning than when the nozzle was held   H   ,_,.   ye,     =-=   W;
. . .       l i r i» yy,  
12 to 15 iuehes from the plants. TDE and endrin wet- [Tig_ l_- gui-ning ·--»—·    is -  Q/T   »z   V i ...,_,__
table powders did not cause any burning of leaves or of H tobacco lcuf   `TT*T    ' `"     f
buds, but TDE at 4 pounds (actual) per acre-four Citufcd l’Y_““ cx'   {ff        T T
times the recounueuded rate—caused a yellowish mot- (csswcly hlgll mm     i k ,  v_  
_ _ , _ . _ of an emulsifiable `    ,,,;   g _·       A
thug or mosaic of the treated leaves. Tlus leaf dis- mnccmmtc ap_   { ,_=_   Q if  _V‘__ j ,   ·— i. »- .
coloration gradually disappeared with no injury to plied with the   ..T_  T ...,,     4u
the plants, spray nozzle held   ._._           TT   __`. _
· . . . . .      e  >  ?i"~?‘* ··   T* ’‘; » ,»· , » L.
l.eaI injury, caused by the solvents in the emulsl- $00 §l°s° (4 *0 6   _ ·  $,,2;- ....   Q-; ;,-·¢  
liable eoueentrates, showed up as oil-soaked areas 20 Lnlelilfi) t; :11;     .,,-. Y;    T A
. c . . . t · 1 .     * * Q  °·‘‘ , _--=  .  
to $30 minutes after spraying. These areas witlnn 24 speckled areas 4 * .-·    , T-     ·--    lb
hours turned tannish brown and eventually dropped will eventuallv ,      -t‘‘: Y  
4. drop out of the W ~ tk      vg
lTl`hurstou. ltiehard. Malforined tobacco leaves. Ky. l"tll`Il] leaf. · * » ~  . .   _,t·- *  
and lhuue Seieiiee $(2): ($-7. 12 (1957). T   . --       T
2 'lhurston. ltiehard, and \\’ade, Claude F. Phytotoxieity of _   `    
llI$\‘(`llt‘l(li\l illltl S[)l'll}' ll`(‘1lllIlt‘lllS ll) l)\lTll‘}' t(ll)ilC(`O. rlT()l)LlCC(l TT j T       ~
130 t2$); 22-27 (1960), _ _ V  - .     :_    ,
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fi l{liN'l'U(ZKY Flxuxi ANI) flown-; SCIENCE—\VIN'1`lZR 1901
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