الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Mealybugs are considered one of the most important pests in the grape
production area. Therefore, the present study concerned with the ecological studies
on the mealybug species and their associated natural enemies on grapevine in
Fayoum Governorate for two successive years from 2015 to 2017; the effect of the
main weather factors on the recorded species, and microbial and chemical control
studies on the predominant mealybug species which may provide some basic
knowledge about mealybugs which need for recommended control programs. Also,
evaluation of
Ecological studies
Three mealybug species, belong to the family Pseudococcidae, were
recorded on grapevine; the grapevine mealybug, Planococcus ficus Signoret, the
striped mealybug, Ferrisia virgate Cockerell, and the pink hibisicus mealybug,
Maconellicoccus hirsutis Green, in addition to the predator Dicrodiplosis
manihoti Harris, (Diptera: Cecidomyiidae) associated with P. ficus colonies. The
obtained results showed that P. ficus individuals were found throughout the year
beneath the bark of grapevine trunks, while F. virgata was recorded on leaves and
grape bunches and M. hirsutis was recorded on grape bunches. The population
fluctuation studies on P. ficus showed that the total individuals of this mealybug
recoded five peaks and seven peaks, for first and second year, respectively. The
highest peak was recorded at the end of August and mid-September, for first and
second year, respectively. The effect of maximum and minimum temperatures on
total individuals of P. ficus, on trunks of grapevine, was positive and insignificant in
the first year, and positive and highly significant in the second year. The effect of
mean relative humidity was negative and insignificant in both investigated years.
The combined effect of main weather factors on total individuals of P. ficus was
insignificant in the first year while it was significant in the second year.
Microbial and chemical control studies
The results of Beauvaria bassiana (Bals.-Criv.) Vuill., and Metarhizium
anisopliae (Metchnikoff) Sorokin bioassay on P. ficus showed that M. anisopliae
was more effective than B. bassiana. The results of the lyophilization of conidial
spores of both fungal isolates showed that there was no reduction in the viability of
B. bassiana conidia immediately after the lyophilization process and for two months
after storage, but after the third month of storage the vitality of the lyophilized
conidia decreased by 16.6%. On the other hand, the fungal isolate of M. anisopliae
was more sensitive to the lyophilization process; where the percentage of decrease in
the viability of conidia directly after the lyophilization process was estimated at
8.08%. The decrease in the conidial viability for this fungal isolate continued with
storage, where the loss of viability reached 99.9% compared to the initial
concentration that was used in the lyophilization process after three months of
storage. When comparing the results of the bioassay of the freeze-dried conidia with
that of the non- lyophilized, the results showed that the non-lyophilized conidia of
M. anisopliae was more effective against mealybugs than the non-lyophilized
conidia of B. bassiana isolate. And the effectiveness of the dried conidia of B.
bassiana was higher than that of the non-dried conidia of the same isolate, where the
LC 50 value was decreased by about 10000 times when using the freeze-dried
formulation for this fungal isolate. On the other hand, the dried conidia of M.
anisopliae showed lower activity against grape mealybug, where the LC 50 value was
increased by about 1000 times compared to the non-dried conidia of the same fungal
isolate.
The current study also included an assessment of the compatibility between
tested fungal isolates and agrochemicals commonly used in vineyards, which gives
basic information about the possibility of mixing these isolates with
chemicalpesticides and using them in the applied control of the pest. The results of
the compatibility of the fungicides on the tested fungal isolates showed mixed
results. While some copper compounds showed an invigorating effect on the
germination of these fungal isolates, other types of fungicides such as Tilt ® ,
Rizolex ® , Nasr zim ® , Topsin ® inhibited the germination of conidia for both isolates
inhibition. Also, some insecticides such as Sunclopride ® , Telphast ® had a stimulating
effect on the germination of the tested fungal isolates when used at certain
concentrations. Regarding the effect of plant growth regulators, the results indicated
that Dormex ® completely inhibited the germination of both isolates, while the use of
Gibbest ® activates the germination of both isolates. The Magictone ® formulation
inhibited the germination of B. bassiana while, the same combination activated the
germination of M. anisopliae.
The results showed that all the mixtures between the fungal isolates and the
tested pesticides were more effective against P. ficus compared to the fungi or any
of the pesticides alone. The results also showed that no antagonism was shown
between these fungi and the pesticides tested. Mixing M. anisopliae with 1/8 of the
recommended field dose of Sunclopride ® had the highest synergistic effect against
the third nymphal instar P. ficus, followed by the mixture between M. anisopliae
mixture and1/4 field doses of the previous pesticide. Concerning the mixing of M.
anisopliae with different concentrations of Telphast ® , the results showed that all
mixtures of the fungus with the concentrations tested for this pesticide had an
additive effect on mealybugs, and the mixing of the recommended field
concentration of Telphast ® with the fungus was higher additive effect. In general, the
response of the fungal isolate of B. bassiana to mixing with insecticides was lower
compared to the fungal isolate of M. anisopliae. The highest additive effect was
recorded when B. bassiana was mixed with 1/4 of Telphast ®.
The results of field application of three chemical insecticides against P. ficus
the Tokuthion ® treatment proved superiority in reduction the mealybug population
by a reduction percent estimated by 98.3%, followed by the neonicotinoid,
Imidazid ® by 65.3% reduction, and finally the mineral oil whose reductive effect of
the mealybug population decreased sharply to 24.3%, fifteen days after application
Key words: Planococcus ficus, Ferrisia virgate, Maconellicoccus hirsutis, the
predator Dicrodiplosis manihoti ,Ecological studies, Beauvaria
bassiana ,Metarhizium anisopliae, Lyophilization, Sunclopride ® ,
Telphast ® , Tokuthion