الفهرس 
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Abstract
Experiments were carried out to study the effect of
temperature and host feeding on the biology of the two
hymenopterous parasitoids, Bracon hebetor (Fam.
Braconidae) and Dibrachys sp. (Fam. Pteromalidae) under
controlled conditions of 22, 26 and 30°C associated with
(65-70) % R.H.. Other experimental studies were bionomics
and feeding capacity of some predaceous insect species and
storage of some predator adults, at two low temperatures,
under different regimes, of nutrition were carried out In
addition, field studies were carried out throughout three years
(1997, 1998 & 1999) in different Egyptian Governorates to
survey host plants, on the cotton bollworms, Pectinophora
gossypiella (Saund.) and Earias insulana (Boisd.) and also
the associated parasitoids and predators. Also, weekly counts
of the two bollworms larvae and its predators were taken by
direct counting to study the fluctuations in population of
different species on cotton throughout three seasons in
Moshtohor (Qalubia Governorate) and Sids (Beni-Suef
Governorate). The changes in relative population density of
predators were also studied throughout 1997, 1998 & 1999
seasons in the two locations (untreated and treated by the
conventional insecticides) fields by using the sweeping net
strokes on cotton plants.
1- Biological aspects of Bracon trebetor and Dlbrachys sp.:
1.1- Bracon hebe/or:
In laboratory, at 22, 26 & 30°C the durations of the
egg stage, different larval instars and pupal stage in addition.
to male and female’s longevity were estimated.
The egg stage hatched after 2.5±0.03, 1.17±0.17 &
0.78±0.08 days at 22, 26 & 300e when reared on
P. gossypiella full-grown larvae. While, by rearing on
E. insulan« larvae, the incubation periods were 2.86±0.0 I,
1.28±0.03 & 0.97±0.1 days, respectively, at the same
temperatures.
1.1.1- Duration of larval stage:
The duration of each instar was estimated under the
same mentioned conditions (22, 26& 30°C). The duration in
days of the first instar larva, when reared on larvae of
P. gossypiella & E. insulana was 1.8 ± 0.007,0.87 ± 0.02 &
0.79±0.008 days and 1.86 ± 0.01, 0.94 ± 0.001 and 0.8±0.006
days, respectively. The second instar larva occupied 1.52 ±
0.004, 0.79 ± 0.001 & 0.065 ± 0.003 days and 1.92 ± 0.07,
0.73 ± 0.005 & 0.63±0.005 days at 22, 26 & so-c,
respectively.
At the same conditions, the third instar larva occupied
1.69 ± 0.001, 0.84 ± 0.006 & 0.49 ± 0.001 days on
P. gossypiella, while on full-grown larvae of E. insulana, this
period lasted 1.8 ± 0.007, 0.76 ± 0.003 and 0.53 ± 0.004 days
at 22, 26 & 30°C, respectively. The fourth instar larval period
elapsed 1.95 ± 0.01, 1.82 ± 0.003 and 1.57 ± 0.006 days at thc
three temperatures, respectively, by rearing on P. gossypiella ..
V-SUMMARY 300
Whilc, on E. ;lIsliltma this period lasted 2.] 7±O.09,
] .92±O.006 & ] .67±O.003 days, res,peclively.
Prepupal stage of B. hebetor lasted ].54±O.O]6,
O.77±O.004 &O.77±O.004 days on P. gossypiella and 1.5±O.02,
O.95±O.Ol& O.78±O.005 days on E. insutan« at 22, 26 &
30°C, respectively.
Durations of pupal stage at 22, 26 & 30°C and
P. gossypiel/a and E. insulana were 5.9±O.03, 4.87±O.003 &
3.5±O.OI and 7.67±O.I, 4.84±O.16 & 3.58±O.08 days,
respectively.
The total developmental;period lasted 16.75, 10.79 &8.72 on
P. gossypiella and 19.78, 10.78 and 8.07 days on E. ;lIsu[mla
larvae, respectively.
1-1-2-The rela UonshiJl between the kinds of food offered to
Bracon hebetor adults, and diffcrent consh,”t
temperatures on longevity and fecundity:
The effect of each 3 constant temperatures; 22, 26 and
30°C and three kinds of food; i.e. (Protein + 10 % sucrose, 10
% sucrose solution and water only) on the fecundity and
longevity of the parasitoid, B. hebetor, when reared on
P. gossypiella, were investigated.
The preoviposition period was shortened, as the
temperature became higher, 1.00, 0.86 & 0.30 days at 300C
when fed on protein + 10 % sucrose, 10 % sucrose and only
water, respectively. It was prolonged to reach O.57±O.1l,
2.00±O.13 & 1.44 days at 26°C and to 2.35±O.3, 2.3±O.l2 and
2.14±O.3 days at 22°C, respectively.
The oviposition period averaged 1O.46±0.44,
8.33±O.22 & 1.OO±0.12days at 30°C~ but at 26°C this period
became l2.5±0.45, 12.38±0.4 and 1.78±O.17 days,
respectively. While at 22°C, this period lasted 17.15±O.7,
l2.13±0.93 & 2.93±0.3 days when fed on 10 % sucrose +
protein, 10 % sucrose & water, respectively.
The post-oviposition periods elapsed 0.86±0.08,
O.80±0.14 and 0.20±0.02 at 30°C when fed on protein + 10 %
sucrose, 10 % sucrose and water, respectively against
1.70±O.13, 2.26±0.12 and 1.57±0.14 days/female at 22°C.
Number of deposited eggs/female:
The mean daily and total number of eggs laid / female
. were affected by the type of food offered to adult females.
The highest daily means in number of eggs / female were
recorded with females fed on protein + 10 % sucrose solution,
being 18.73 ± 0.64, 15.73 ± 0.85 and 11.46 ± 0.05 eggs /
female at 30, 26 and 22°C, respectively. While, the lowest
dai 1y mean numbers of eggs / femal e were 5.30 ± 0.13,
3.68±O.7 & 1.40±0.23 at 22,26 & 30°C, respectively, when
fed on water. The total number of eggs/female has taken the
same trend, i.e. the highest total number of eggs was
associated with females fed on protein + 10 % sucrose
solution (l99.9±4.07, 197.13±14.38 & 197.40±12.4,
respectively) at 30, 26 & 22°C.
Adult longevity: The longevity of B. hebetor females
averaged 21.0±OA, 16.75±4.8 & 12.46±0.4 days at 22,26 &
30e, respectively, when fed on protein + 10 % sucrose
solution. But, when females were supplied with water only
this period lasted 5.78±0.23, 4.57±0.13 and 1.30±0.12 days,
respecti vely.
Reproduction potential and life table parameters:
The multipHcation per generation (Ro) increased by the
increase in temperature from 22, 26 & 30°C. (Ro) values were
0.57, 28.408 & ]08.0 at 22°C, while at 26°C, (Ro) values
were 0.817, 50.32 & 65.393; and at 30°C, (Ro) values were
.92, 29.79 & 62.36. The mean generation time (1’) decreased
when temperature was increased, these values were 10.84,
13.84 and 13.61 at 30°C, against 18.46,21.08 and 21.74 at , , . .
22°C when Bracon adults were fed on water, sugar & protein.
The (rrn) values were -3.02, 0.158 & 0.215 at 22°C; -1.4,
0.212 & 0.231 at 26°C; while those were -7.29, 0.252 &
0.304 at 300e when Bracon adults were fed on water, sugar
and protein, respectively.
1.2- Dibrachys sp.:
Incubation period of eggs were 3.14 ± 0.03, 1.54 ±
0.001 and 0.71 ± 0.001 days and 3.01 ± 0.001, 1.98 ± 0.01 &
0.73 ± 0.00 Iat 22, 26 & 30°C when reared on P. gossypiella
and E. insulana, respectively.
At 22, 26 and 30oe, four larval instars were recorded
for the parasitoid Dibrachys sp, on P. gossypiella and
E. insulana larvae. The first instar larval duration was 2.14 ±
0.01, 1.70 ± 0.01 & 0.67 ± 0.01 and 2.46 ± 0.01, 1.70 ± 0.01
& 0.81 ± 0.002 days. For 2nd instar were 1.95 ± 0.0 I, 1.64 ±
0.08 & 0.62±0.2 days and 1.87 ± 0.01, 1.57 ± 0.009 & 0.87 ±
0.005 days; while for the 3rd instar was 2.4 7 ± 0.02, 1.70 ±
V-StlMMARy0.01 & 0.85 ± 0.004 days and 1.77 ± 0.01, 1.85 ± 0.01 & 0.86
± 0.02 days and the ~th instar lasted 2.60 ± 0.01,2.38 ± 0.01
& 1.54 ± 0.01 days and 2.72 ± 0.02,2.43 ± 0.02 & 1.50 ±
0.008 days, respectively, when all stages were reared on 22,
26 & 30°C and on P. gossypiella and E. insulana full-grown
larvae, respectively.
Pre-pupal and pupal stages, at 22, 26 & 30°C and on
P. gossypiella and E. insulana lasted 2.14 ± 0.07, 1.44 ±
0.014 & 0.73 ± 0.09 days and 1.44 ± 0.001, 1.23 ± 0.01 &
0.74 ± 0.004 days, respectively. While pupal stage taken 80.9
± 0.06, 6.2 ± 0.05 & 3.40. ± 0.01 days on P. gossypiella and
7.30 ± 0.19, 5.90 ± 0.15 & 3.50 ± 0.01 days on E. ills ulan a,
respectively.
1.2.I-Duration of Dibrachys SPA on pupal stage of
E. insulana and P. gossypiella:
No parasitism occurred on P. gossypiella pupae, while
the parasitoid succeeded to deposit on 56 % of the exposed E.
insulana pupae.
In the laboratory, at 26 ± 1°C alld 65-70 % ~.H., the
durations of the egg stage, -the four larval instars, pre-pupal
and pupal stages were 2.60 ± 0.1, (1.83 ± 0.03, 1.90 ± 0.02,
1.78±O.08 & 2.70 ± 0.04), 1.50 ± 0.74 and 7.976± 0.85 days,
respectively.
1.2.2- The relationship between the kind of food offered to
Dibrachys sp, adults, at different constant
temperatures and their longevity and fecundity:
The longevity and fecundity of parasitoid, Dibrachys .
sp. were estimated under laboratory conditions of 22, 26 &
30De whcn adults were nourished by three different kinds of
food.
Pre-ovipositional periods of female was prolonged be
decreasing temperature, being 2.07 ± 0.06, 2.13 ± 0.08 & 2.00
± 0.1 days at 22°C and shortest periods were recorded at 30
,
°C (0.6 ± 0.121 0.80 ± 0.1 & 0.26 ± 0.12 days)by feeding on
protein + 10 % sucrose, 10 % sucrose and water.
The oviposition period lasted 18.80 ± 0.38, 15.20 ±
0.27 & 3.06 ± 0.25 days at 22°C on three food types, but this
period was shortest at 30DC; i.e. 12A6±OA, I0.60±O.37 &
1.80±0.19 days, on the same previous diets, respectively.
Post-oviposition period followed the sametrend, as it,
was prolonged by decreasing temperature and shortened with
increase of temperature.
A mated female deposited the highest total number of
eggs (216.6 ± 4.8, 184.0 ± 3.07 and 157 ± 3.7) at 30, 26 and
22°C when females were fed on protein + 10%sucrose, with
a mean daily deposition of 17.548±OA6, 13.25 ± 0.25 &
10.224 ± 0.19 eggs and the lowest number of eggs obtained
when adults were fed on water only where it deposited 12.29
± 2.79; 8.0 ± 1.3 & 6.21 ± 1.28 eggs with a mean daily
number of 1.30 ± OJ, 0.95 ± 0.05 and 0.80 ± 0.21 eggs at 30,
26 and 22°C, respectively.
The longest periods of Dibrachys, females’ longevity
were 23.46 ± 0.36, 16.20 ± 0.17 & 13.93 ± 0.44 days at 22, 26
and 30°C, respectively, when fed on protein + 10 % sucrose,
while the shortest periods were 8.30 ± 0.17,5.43 ± 0.23 & .
1.03 ± 0.23 days at 22, 26 & 30°C, respectively, when fed on
water only.
1.2.3- Reproduction potential and life table parameters:
Studies were carried out on the effect of different food
types on life table parameters of Dibrachys sp. at 22, 26 & 30
°C.(Ro) increased by the,, increased temperature from 22, 26
&30°C. (Ro) values were 0.285 ,49.364 & 71.46 at 22°C,
while 0.806 ,45.74 and 95.24 at 30°C when fed on water,
sugar and ’protein + sugar. The mean generation time (T)
decreased when temperature was increased, these values were
obtained 10.97, 13.937 & 14.25 at 30 while at22°C 24.45,
30.80 and 31.087.
II-Bionomics and feeding capacity of some predaceous
insect species:
11.1- Hippodamia tredecimpunctata:
In the laboratory, at 26 ± 1°C and 65-70 % R.H., the
durations of the egg stage, different larval instars and pupal
stage in addition to male and
female’s longevity were estimated. The 1st, 2nd, 3rd and 4th
instar larvae consumed 59.98 ± 1.39, 144.70 ± 2.7, 254.66 ±
12.12 and 602.26 ± 16.78 eggs of P. gossypiella and 23.62 ±
0.5,55.90 ± 0.94,91.40 ± 1.08 & 234.80,± 3.2 eggs of
E. ins ulan a, respectively, with a total consumption of
1061.20 ± 26.69 (663-1167 eggs) of P. gossypiella and 406.0
± 3.96 eggs of E. insulana. An adult male consumed 3171.9 ±
139.91 eggs with a daily mean of 65.4 ± 0.74 eggs of P.
gossypiella and 1919.9 ± 32.4 E. insulana eggs; while the
total consumption of P. gossypiella & E. insulana eggs were
4480.89 ± 76.34 & 2834.6 ± 92.36 eggs, respectively.
A mated female deposited 836.6 ± 18.1 eggs
throughout an oviposition period of 15,.16 ± 0.07 days when .
fed on P. gossypiella, and” 377.85 ± 10.0 eggs when fed on
E. insulana eggs throughout an oviposition period of 44.15 ±
0.48 days.
11.2- Coccinella undecimpunctata;
Durations of the 4 larval instars averaged 2.59, 2.68,
3.86 and 2.73, respectively when reared on P. gossypie/la,
while when reared on E. insulana eggs, the durations were
2.84, 3.79, 2.89 & 3.30 at 26°C. During these instars, larvae
consumed 41.86 ± 0.9, 117.6 ± 3.3, 344.73 ± 3.9 and 411.64 ±
5.8 eggs of P. gossypiella, against 25.10 ± 1.13, 120.79 ±
0.73, 166.94 ± 7.28 and 239.05 ± 6.22 eggs of E.insulana.
The total consumption during the larval stage was 969.136 ±
7.5 eggs of P. gossypiella and 542.68 ± 6.5 eggs of
. E. insulana. An adult male consumed 2548.8 ± 89.7 eggs of
PBW, while it consumed with an 1979.7 ± 48.98 eggs of
E. insulana. The overall daily mean number of consumed
eggs of paw and saw were 57.4 ± 0.91 and 43.91 ± 1.16
eggs, respectively; while female fed on more amounts of
P. gossypiella eggs ~134.2 ± 71.2 eggs and 2742.17 ± 155.7
307
eggs of E. insulana.. The overall daily mean number of
”
consumed eggs ofPBW and SBW were 60.20 ± 1.05 & 54.30
± 0.89 eggs, respectively. Thus indicating higher feeding
capacity of females, A mated female deposited 797.05 ± 18.99
eggs throughout an oviposition period 50.16 ± 0.48 days when
reared on P. gossypiella eggs and 519.16 ± 31.25 eggs
throughout an oviposition period 41.31 ± 0.68 days when
reared on E. insulana.
I1.3-Storage of H. 13-punctata at two low temperatures
under different regim, es of nutrition:
The results indicated that:
1- Adults lived longest then fed on type (1) dite; i. .e., protein,
milk yeast, ascorbic acid, sucrose and water. Female and”
male lived for 156.05 ± 4.80& 145.90 ± 4.30 days,
respectively at 12-14°C and 142.70 ± 7.30& 135 ± 5.80
days, respectively at 8-10°C. on contrary, adults kept, in
refrigerator, and fed on type (5) dietIsucrose and water)
lived the shortest life-span, being 48.~ ± 4.9 and 45.0 ± 4.8 .
days at (l2-19°C) and 59’,25 ± 5.8 and 75.05 ± 6.36 days at
(8-100C) for females and males, respectively.
2- Effect on fecundity of the resultant adults: After a storing
period of 3 months, the pre-oviposition period of mated
H. 13-punctata female was 5.78 ± 0.34 days and produced
an average total number of358.43 ± 8.38 eggs throughout
an oviposition period 36.07 ± 1.4 days. While, after 5
months, the produced average total number decreased to
167.6 ± 10.09 eggs throughout an oviposition period of
25.17 ± 0.35 days,
308
3- Also~ adults of C undecimpunctata, at type (I), the
females lived 150.96±6.41 days and males 140.12±5.4
days at 12-14°C and 124.0±7.97 and 102.4±6.6 days for
females and males, respectively, at (8-10°C).
4- Effect of storing for 3 months at 12-14°C on the fecundity
and longevity of C undecimpunctata, a single female
deposited an average total number of 211.2 ± 7.5 eggs
throughout an oviposition period of25.46 ± 0.4 days with
63.1 % hatching, while the average total number of eggs
and % hatching obtained from a single mated female
resulted from adults ,storing for 5 months at 12-14°C was
174.8 ± 7.07 eggs with 45.97 % hatching.
Field studies:
Survey of some host plants, which are attacked by PBW &
SBW:
Eight plant species belong to 3 families were surveyed
at Moshtohor and Beni-Suef, namely; Gossypium
barbadense, Hibiscus canabinus, H. sabdariffa, H. trionum,
Zanthlmum stanmarium, Zen maize attaked by E. insulana
and Sesamum indicum, which attached by P. gossypieila. this
plant new first time in the world. ’ ..
Survey of some bollworm parasitoids :
Ten hymenopterous parasitoids were surveyed on
Pectinophora gossypiella and Earias insulana namely;
Parasierola sp.on P. gossypie/la (Bethylidae), Apanteles sp.
on P. gossypiella, Bracon brevicornis, Bracon hebetor and
Chelonus blackburni (Braconidae)on P. gossypiella and
V-SUMMARY 309
E. insulana pupa, Brachymeria sp. (Chalcididae), Exeristes
roborator (Ichneumonidae), Dlbrachy« sp. P. gossypiella and
E. insulan«, Sphegigaster sp. P. gossypiella for these first
time of PBW (Pteromalidae), Trichogramma evanescens
(Trichogrammatidae) on eggs of P. gossypiel/a and
E. lnsulana.
Percentages of parasitism were generally low
(maximum percentages 8.6 & 8.3 at Moshtohor and 6.9 & 7.3
at Beni-Suef) on cotton plants in 1998/1999 & 1999/2000,
respectively. Among the recorded parasitoids, B. hebetor was
the most abundant, followed by B. brevicornis, then
Dibrachys sp., while Sphagigaster sp. was the least common.
C-Survey of pink and spiny bollworm predators:
Thirty-two predaceous insect species were surveyed
throughout the three seasons of study, being 9 coccinellids,
one staphylinid, one cecidomyiid, one octhiphilid, two
syrphids, four anthocorids, one chrysopid and one
dermapteran. Three true spider species were also found and
recorded as predators on pink and spiny bollworm.
Percentage of infestation by pink and spiny bollworms to
fruiting structures of cotton plants:
These experiments aimed to estimate the effect of
PBW and SBW on pin squares, blooms and green bolls during
the three successive seasons 1997, 1998 & 1999.
A- In Moshtohor region:
1- Effect on pin squares:
In Moshtohor region, the overall seasonal mean
percentages of infested pin squares by both pink bollworm.
and spiny bollworms at the two fields (untreated and treated
by conventional insecticides) were (5.2, 4.27 & 5.4 %) and
(3.1, 3.0 & 3.4 %) during 1997, 1998 & 1999 seasons,
respectively.
2- Effect on blooms:
The overall seasona,l mean of percentages of infestation
blooms during three seasons were (5.8, 5.7 & 4.5 %) and (3.6,
3.1 & 2.66 %) in untreated and treated cotton fields,
respectively. The highest peak of infestation reached 12 % in
June 31st during 1997, 14 % during July 15th during 1998,
while in 1999 season this percentage was 11 % in July.
3- Effect on bolls:
The overall mean of percentages during three seasons
were (26.86, 33.14 & 27.9 %) in untreated fields and (16.14,
24.8 & 20.0 %) in treated cotton fields.
B- In Beni-Suef region:
1- Effect on pin squares:
The overall. seasonal mean percentages of infested pin
squares by both species on cotton plants, during the three
seasons, 1997, 1998 & 1999 were (4.54,6.00 & 5.50 %) in
untreated fields and (2.58,2.90 & 2.90 %) in treated fields.
3Jl
2- Effect on blooms:
The overall percentages of infested blooms by both
pest species on cotton plants during the three seasons 1997,
1998 and 1999, were 6.18,5.6 & 7.5 % and 3.5,3.6 & 4.3 %.
in untreated and treated cotton fields, respectively. -
3- Effect on bolls:
The overall mean percentages of infestation by both
pink and spiny bollworm during the whole season at the two
fields (untreated and treated) were 39.14,34.1 & 37.07 and
15.7, 15.0 & 12.07 %, res~ective1y.
Seasonal abundance and total population of predators:
a- By using direct counting method:
The populations of insect predators were, generally,
higher in Moshtohor than Sids throughout 1998 and 1999
cotton seasons. During the 3 seasons, in Moshtohor, the
respective total numbers of predators were 2429, 2355 &
2970, while in Beni-Suef, the total numbers of insect
predators in cotton were 2085, 3276 & 1883 individuals.
Family Coccinellidae
Eight lady beetle species abundant on cotton plants were
found during the three seasons, 1997, 1998& 1999. The final
total counts of ladybird betles allover the cotton season were
estimated by 814, 939 &1142 individual, in Moshtohor and
969, 933 and 733 individual in Bein-Suef throughout
1997,1998& 1999 seasons, respectively.
These counts represented 33.51~ 71.19 &40.17% of the total
population counts of predators throughout the three seasons,
respectively. While in Beni-Suef region thee counts
represented 31.41~ 65.33 and 28.84% of total population.
counts of predators.
- Family Staphylinidae :
Adults of Paederus alfierii were the only staphylinid
found on cotton plant in Moshtohor and Beni-Suef regions
throughout the 3 successive seasons. The overall total
numbers were 173, 96 &,,68 individuals in Moshtohor during
the 3 seasons, respectively. While in Beni-Suefregion, the
overall total numbers were 218, 100 & 153 individuals
throughout 1997, 1998 & 1999 seasons. These count
represented 7.12, 7.27 & 2.39 % in Moshtohor and 7.07,3.5
& 6.02 % of total predators, respectively.
- Family Anthocoridae :
The average total number of Orius spp. nymphs and
adults counted on cotton plants throughout 1997, 1998 and
1999 seasons in both locations Moshtohor and Beni- Suef
were 470, 600 & 694 and 983, 307 & 323 individuals,
respectively. This counts represented 19.35, 80.43 & 24.3 %
and 31.86, 17.98 & 12.7 % of total predators count,
respective Iy.
- Family Chrysopidae :
Chrysoperla carnea Steph. stages of the predator
(eggs, larvae, pupae and adults) were directly counted 1100
plants. The highest total population (522, 288 & 474)
individuals at Moshtohor and 583, 180 and 328, these count at
Beni-Suef represented by 21.49, 12.23 & 16.67 at Moshtohor
and 18.9, 11.28 & 12.9 % of total predators counts at 1997,.
1998 & 1999 seasons, respectively.
~Family: Cecidomyiidae:
Phenobremia aphidivora: This predaceous insect was
relatively much more abundant during 1997, 1998 seasons
(counts 113 & 111 individuals, respectively). But, PII.
avidlvora completely disappeared on cotton plants during
I 1999 season. While in Beni-Suef, the predator has very low
population during 1999 season, the total count during all
season was 57 individuals with 2.24 %.
- Leucopis sp.:
This predator was absent during 1997, 1998 season in
Moshtohor and 1999 in Beni-Suef. The overall total number
of Leucopis sp. Counted larvae larva were 84 individuals
represented 2.95 and in Moshtohor and 59, 124 individuals,
represented 1.91 and 8.5 % in Beni- Suefduring 1997 and
1998 seasons.
- Syrphids:
Fewer numbers of total syrphids (larvae and pupae)
were counted on cotton plants in Beni-Suef region than
Moshtohor iocation throughout the three seasons of study.
The total numbers of syrphids counted, throughout the three
years of study, were 122, 105 & 93, represented 5.02, 4.46 %
of total predators at Moshtohor, while in Beni-Suef, the total
numbers ofsyrphid larvae and pupae of this predator were 79~
86 & 48~ respectively) throughout the 1997, 1998 & 1999
seasons, respectively.
- True spiders:
The totalcountS~f true spider species on cotton plants
at Moshtohor and Beni-Suef during 1997~ 1998 & 1999
seasons were 215~ 216 & 136 individuals represented 8.85,
9.17 & 4.78% of total predators, in Moshtohor, respectively.
In Beni-Suef the total co, unt of true spider] 94, 241 & 234
individuals, represented 9.21, 11.28 and 6.29 % of the total
predator, respectively.