الفهرس 
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Abstract
~even plant species belonging to family Verbenaceae
were investigated for feeding deterrent materials to the
51;l! inst ar nymphs of ¥,histocerc a &”2,~.l.~ (Jrorsk~).
The plant speoies examined wers, V...e.•.rbena---- su..-p.•~ina.•~. ,
Veroena- ~o-r-ia. •.•Oitharexylu-m quaarangu1ar.e•• ~-,ectona granais, , _. -,
O,a-r-y-o-p-tr-i-s”.inoaoa , L.antana ca.mara, V,it-ex angus-eastus, ,-- - -’.’
Olerodendero~ ~~e~~!. Oleroaenaero.~ sJlen.ae~s.Durants p~~mierl
and Lappia uodiflora.
In Verbena Bupina and Lippia nodiflora whole plant ware
.-.....:,----~-- . ---- .
used. In the other nine species, leaves .and stems vvera
examined. VfhGGsver, possible flowers and fruits were also
in~esti~ated. The dry p~wder of pl&1t organs under study
ware used to p~epare a 10 per ce~t ethanol extract. ~ilter
papers were impregnated with the extract, sprayed with sugar
solutioiJ. ’O...•~5Uweighed and offered to starved 5,tll- instal’
locust nymphs. For control, filter papers sprayed with sugar
solution only were uaed, The weight consumed from filter
papers impregnated with the aifferent eztraets in comparison
with cor~tro1 was used as an indication for the presenoe or
absenoe of feedlng _. b produced more than 90 per cent
feeding deterrence ware those of the stem of Teotona
grandis, stem of C-io-har-ex~ylum-q~--u-.a.d-.r.a-n-g-u.l-a--r-e, the fruit
of T. granoia, leaves of L~tana camara and the leaVe$
of verben~ ~~r~~ respectively.
Different solvents were used for the extraction
of feeding deterrents from the plant species which gave
good deterrenoe with the ethanol extraot• Resul~.
re”Yealed tbat polar sol”Yents are better tban non-po·lar
ones in ex’l..raction of feeding deterrent s in these species,
a nd the best rasul~s were obtained with ethanol.
Benzene also was effeeti”Ye in many cases, but not significantly,
while chloroform, .n-hexane and diethyle~her
were lesS effective in most cases.
Ethanol extract of dry powder
of Lantan.a-- c~am-a-r-a- •...
leaves was partitioned with petroleum ether, ethyl
acetate and chloroform respectively, allthepartionins
solvents containeds,j.goifiCant amounts of feeding
deterrents, while the residue did not •
.The dry powder of the leaves of Lantana camara
was extracted five tiaes with petroleum ether, then<five times with ethanol, both the ethanol and petroleum
ether extracts contained enough feeding deterrents to give
statistieally significant resul.t a-:-~.
A petroleum ether extract was prepared, the solvent
evaporated and the resid ue applied to a silica gel column.
The colum.n was elnted with petroleum e·bb.er,petroleum eth0I”
and ether 1=1, ether o,Dly ether and ohloroform 1:1, chloroform
alone, chloroform-methanol 9:1 and 1:1 and methanol
only respectively.
All the a)Ove fractions were bioassayed for their
feeding deterrent aotivity, the best results were obtain0d
by fractions 1 and 2 and methanol fraotion.
Fraction ona of tue chromatographic separation was
used fa!? phytochemical screening. Tests for glucosides,
carbohydrates and alkaloids were negative. Liebe~man-
Burchard’s test for sterols and/or triterpenoids was performed,
it ga\1e positiive results, Vlhic~1was further confirmed by
$OlkOWSki’s test 7mich indioata that tha active ingredient in
Lantana oamara is an unsaturated sterol or a trite~penoid
compound.