BIOLOGICAL STUDIES ON ACARINA AND SOME
BIOCONTROL METHODS
Yousef Ramadan Yousef El-Tantawy
ABSTRACT
The present investigation focuses on two points the first concerns biological studies on the
predaciuos mite Proctolaelaps pomorum (Oud). Moreover, it was planned to study the life
cycle of the mite Acarus farris (Oud) well known to the one of the dominant mites of stored
products. The second point of study was on control agents and we prelectes two biological
compounds, tracer and biofly against the two red spider mite, Tetranychus urticae (Coch) on
the larvae, nymph and adults on the other hand, as for Acarus farris. The study includes the
whole stages of the mite, the egg, larvae, nymph and adult.
1.
Biological studies:
Result indicated that, the predacious mite P. pomorum can consume different diets since he
succeeded to consume larvae and pupae of Drosophila melanogaster, and also larvae and
nymph of the red spider mite T. urticae. Moreover, the successfully nourished the different
fungi species that were offered to it Fusarium oxysporium, Penecellium notatum and
Aspergillus niger and also on pollen grain of Ricinus commiuns. Results showed that the
incubation period of the egg of P. pomorum was 3.2 days when nourished as R. commiuns as
1.8 days when offered the pupae of drosohila, however that period deceased to 1.5 days on
the rest of offered diets. On the other hand, reared indicated that period come to the
maximum 2.3 days were reared on R. commiuns were offering the minimum period was 1.6
days will the compound diet consisted of larvae and pupae of drosophila and/or the fungies.
F. oxysporum interval life Spain of P. pomorum come to its maximum 2.9 days on P. notatum
while the minimum record 2.0 days on pupae of drosophila. On the other hand, 2nd the
interval come to its maximum record 3.2 days record on Penicillium. notatum while the
minimum record was 2.2 days record on the complex diet of larvae and pupa of Drosophila.
Records indicated that the whole life cycle was different according the offered diet. The
maximum record was got when offering R. commiuns. Its mean was 10.5 days while the
minimum record was 7.1 days reared on the compound diet of larvae and pupa of
drosophila. Records indicted that the whole life cycle was different according the offered
diet. The maximum record was got when offering R. commiuns. Its mean was 10.5 days while
the minimum record was 7.1 days reared on the compound diet of larvae and pupa of
drosophila. It was found out that the fertility of females was affected according to the
offered diet. Results showed that maximum mean numbers of laid eggs on the whole life
span of the mite was 51.3 eggs when offering larvae and pupae of drosophila. On the other
hand, the minimum record was 17.3 eggs when offering R. commiuns. The offered diet was
found to affect the life span of females. The records indicated that the maximum mean was
43.0 days when record on the larvae and pupae drosophila. While the minimum record was
25.6 days record on R. Communis the quantities of compound diet of the predator our
records indicated that P. pomorum consumed as a mean number 13.3 larvae of T. urticae.
Larvae reared in laboratory, however when reared on pupae of Drosophila consumed only
1.3 pupae. On the other hand, the maximum record that the female mite consumed during
all its life span was 421.6 larvaes of T. urticae while the minimum record mean was 27.3
pupae of drosophila.
B.
Acarus farris:
The culture of the mite was got from laboratory studies on wheat bran for the first time in
Egypt and was also got when reared on banana fruits without cover and also on R.
commiurns (28oC and 90% R.H and/or 10oC and 70% RH) the incubator period of the eggs of
A. farris was 1.6 days reared on R. comminus while it was only one day only when reared on
bran or banana fruits (28oC + 90% R.H). It was 4.1 days however it was 3.8 days and 3.2 days
reared on bran. The life span of larvae was clearly affected according to the offered diet and
both temperatures l was R.H. the maximum record was 2.0 days reared on R. comminus at
28oC + 90% R.H) followed by 1.5 days reared on banana fruits while the minimum record got
from when reared on bran, only one day. On the other hand, these record on (10oC + 70 R.H)
it as on other study the maximum record was 4.3 days reared on R. comminus. While, it was
4.9 days reared on banana fruits. The last record was 3 days reared on bran. The life span of
first nymph of A. farris reared on R comminus (28oC + 90% R.H) was 1.5 days while reared on
banana fruits 1.3 days. On the other hand, the minimum record was 0.9 days reared on bran
however, those records 10oC + 70% R.H) the life span of 1st nymph was the highest series it
reached 47.1 days reared on R. comminus while reared on banana fruits was 3.8 days. The
least record was 3.2 days reared on bran. On the other hand, the 2nd life span of the nymph
of A. farris was 1.4 days reared on 28oC + 90% R.H) followed by these reared on banana
fruits 1.1 days, however, the minimum record 1.1 days reared on bran, those reared on 10oC
+ 70 R.H) all nymphs turned to hypopus and while led to all nymphs to die. In concern of life
cycle of A. farris it took 6.0 days reared on R. comminus at 28oC + 90% R.H.) followed by that
reared on banana fruits for 4.9 days while the minimum record was 4.9 days from these
reared on bran at 10oC + 70% RH.) was 4.0 days.
2.
Control measures:
Experiment was done in the laboratory of Agriculture of Kafr El-Sheikh Department
of Economic Entomology to the effect of tracer and biofly. Results indicated that the toxic
effect of the two chosen toxicants were pupae on P. pomorum since LC50 was zero in all tests
on the other hand the toxic effect of biofly and tracer against A. farris was moderate against
adults of the mite, however, the effect was moderated on the nymph stages for the biofly
and high for tracer. The effect of tracer was very clear with high effect against larvae of A.
farris was moderated for biofly. The toxic effect on eggs of P. pmorum was low in concern of
biofly but moderated in concern with tracer the toxic effect of the two applied toxicants
against the adults of the two spotted spider mite wasn’t the same since it was high with
biofly and was less with the tracer. As with the nymph of the mite the toxic effect of the
biofly was very high, but for the tracer it was moderate. As for the larvae of the biofly
against the two spiders mite it was moderate while the tracer was very high.