الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
The present work is a study on the use of vapours from the oil of Acorus calamus rhizomes in controlling
different stored product>inse~~s; represented by five
species, 1.e., Sitophilus granarius (L.), Sitophilus
oryzae (L.), Rhizopertha dominica Fab., Tribolium
confusum (Duv.) and Callosobruchus chlnensis (L.).
The efficiency of the vapours against these five
species, both in their adult stage and mos~ of the ~ature
stages, were not assessed only by the direct effect
on the treated individuals, but much emphasis was given
to study the other effects on the biology of the survivors
from sublethal treatments and their offspring, as
well as on th.e viability and biological activities of
treated insects during and after treatment. Also,counts
of the number of offspring emerged from the adult foods
used during and after fumigation were carried out.
Initial attempts have been made to study the rate
of evaporation of Acorus calamus oil as affected by the
exposure period and temperature, its sorption as affected
by the type and amount of the fUmigated food material
and the ability of the vapours to penetrate through
treated seed.s. In addition, the active ingredients in
the oil were identified.
A thorough review of literature has been presented,
and from which it appeared that the work done on the
stored-product insects is still of preliminary nature,
and no systematic studies were carried out on the use
of vapours of the oil of Aoorus calamus in fumigation
practices. Also there are so many points to be studied
in this respect until we could reach to the basic knowledge
necessary for presenting final recommendations
for the practical use of the active vapours of the oil
as a fumigant. Certainly, this will depend on any privileges
of these vapours on the other conventional
fumigants. used at present.
All methods and technique have been 4escribed in
details, including rearing of the insects, separation
and preparation of the developmental stages for fumigation,
technique of fumigation and post-fumigation
studies on the treated insects. All the factors whioh
might affect the results of these fumigation tests were
considered.
~or reasons of convenience for representing the
results, this work has been divided into two parts, as
follows :
Part I : Toxicity of Acarus calamus oil vapours to five
species of stored-product insects with special
ref’erence to their latent effects on the survivors.
Part II: Active ingredients, evaporation, sorption and
penetration of Acorus calamus oil vapours.
The followirig are the main conclusions deducted
!rom this study :
1. The period of exposure appeared to be·the main factor
affecting the effici~ncy of the vapours of Acarus
g,alamus oil, as indicated by the considerable increase
of both direct mortality and latent effects by doubling
or tripling the period of exposure using a certain
level of dosage. whereas the increments in
mortality by increasing the dose for a definite
period of exposure were not noticeable within the
range of’dosages tested.
2. Adults_of c. chinens1s were the m9st susceptible to’
the Acarus calamus oil vapours, followed by S.
sranar1y~ adults which were more susceptible than
§.. 2,ryzae adults. Adul ts of both T. confusum and
~. dom1n1ca were completely resistant to all doses
and periods of exposure tested in this stUdy; thus
resulting in the faot that this material will not be
of any use for the oontrol of these two species.
J. Acorus calamus oil vapour~ exhibit ovi.cidal toxicity
against eggs of £. chinensis, !. grane.rius and §..
oryzae. The eggs o~ £. chinens1s were the most
susceptible and ~~ g~~arius eggs were slightly more
susceptible than~. oryzae eggs. In all cases, the
younger eggs were more atf~cted than the older ones.
The larvae and pupae of these three insects, all of
them live internally in the infested seeds, and
also all the immature stages ot T. confusum did not
show any appreciable susceptibility to the vapours.
4. Dosages of the oil of Acorus calamus as low as 1 ull
400 ml (equivalent to 2.5-- ul/litre) were satisf.actory -
effective against the most susceptible species, especially
with prolonged periods of exposure.
5. The number of offspring emerged. from the adult foods
used dur’ing and after fumigation for ~. granarius,
~. oryzae and £. chinensis was consid~rably less
than the respective controls. In this respect also,
the response to the increase of expos~e was much
more than the response to the increase of dose.
In the case of 1.. gOnfusYm, no appreciable d1:t’ferences
between the treatments and controls were observed.
6. Acorus calamus oil vapours reduced the fertility of
~. oryzae and ~. confusum, as well as the fecundity
of~. chinensis. There was noticeable decrease in
the number of progeny of the treatments as compared
with the controls, ~specially in the case of ~.oryzae
adults exposed for long periods. This effect could
be attributed to the disruption in the reproductive
process of the insects.
7. The insecticidal compound . of Acorus calamus oil
was ’identified bY’ GO and GO- KS coupJ.1ng t
as well as by toxicity studies t &8 B-asarone1D.. cis
and trans isamer1des.Eugeno1 and eugenol~ethylether
were not toxic as fumigants for the insects.
8. Results of GO technique revealed that the volatilization
of B-asarone 1s very low. Accordingly, Acorus
calamus 011 could not be used as a fumigant in the
fumigation practices in which the time factor is
important. Also, the evaporated amounts decreased
wi th decreasing the tenperature from .30 to 25 and
o 0 15 c. At 7 C there was no evaporation for c1s-Basarone
and only 0.67 , of trana-B-asarone was evaporated.
9. Tests on the inSecticidal action of the Acarus calamus
oil vapours at different temperatures revealed that,
as the ’temperature decreased from 30 to 25°C the
mortalities among the test insects decreased considerably,
e.g. from 79 % to 5 % for [. granarius
adults and from 73 % to 6 % for s. oryzae adults
using a dose of 10 ul for one week exposure. At
15°0, no mortalities were recorded. These findings
indicate that the use of Acorus calamus oil as a
fumigant at temperatures below 30 °C will not be of
any use.
10. The vapo’l1rsof the oil of Acorus calamus are highly
absorbed by the treated commodities, as indicated
by the decrease in mortality of insects with increasing
the amount of food material on which they were
treated. The percentages of mortalitie~ of ~.granarius
decreased from 80 to 77 % and those of s. oryzae from
81 to 65 % as the amount of wheat grains was increased
from 5 g to 25 g using a dose of 10 ul for one week
expos’ure. By further increase to 50 or 100 g of
wheat grains there was almost no effect. The whole
wheat flour was much more absorptive than the whole
kernels, to the extent thatp~it might cauae complete
failure of ~the- treat.m. - .e. nts. The percentages of
mortality of s. granarius adults in the presence
of 25 g wheat grains reached 100 % after exposure
to vapours from 10 ul oil for 2 weeks exposure, compared with only 2 % mortality when the same·
amount of food was used as whole wheat flour. Hence,
sorption of A. calamus oil vapours into the food
material is an important factor affecting their action as a fumigant.
11. Acorus calamus oil vapours, under the conditions of
these’tests, did not penetrate the cowpea seeds.