Flow Nets Prepared By: Eng. Hayder M. Jasem AL- Mosawey Supervisor : Dr. Mohamed Shaker.
Sara A. A. Kehail and Hayder Abdelgader
1
Testing of the Egg Parasitoids Testing of the Egg Parasitoids Trichogramma bourarachae Trichogramma bourarachae Pintureau Pintureau and and Trichogramma nerudai Trichogramma nerudai Pintureau against some Lepidopterous Pintureau against some Lepidopterous insect pests in Sudan insect pests in Sudan Sara A. A. Kehail and Hayder Abdelgader Sara A. A. Kehail and Hayder Abdelgader Agricultural Research Corporation, Crop Protection Agricultural Research Corporation, Crop Protection Research Centre, P. O. Box 126 Wad Medani, Sudan Research Centre, P. O. Box 126 Wad Medani, Sudan Introduction Introduction Trichogramma (Hymenoptera: Trichogrammatidae) are extremely tiny wasps, the female Trichogramma lay their eggs within a host eggs. Each female parasitizes from 10 to 190 eggs during its life. More than one parasite egg may be inserted into each host egg and this is based, on the egg size. After hatching, the parasitoid larvae feed on the contents of the host egg. The wasps pupate within the egg and adults chew an emergence hole to escape. There are several species and strains of Trichogramma, which vary considerably in their ability to control different insects and in their adaptation to different environmental conditions and crops. Trichogramma have been used as inundative biological control agents against a range of agricultural pests, mainly lepidopterans. Objective Objective The current study was carried to test the acceptance of two Trichogramma species (Trichogramma bourarachae Pintureau; and Trichogramma nerudai Pintureau) against host eggs of different Lepidopterous insect pests in Sudan. Trichogramma Wasp A female Trichogramma wasp while laying her eggs inside a host egg A Trichogramma wasp while emerging out of the parasitized egg Materials and Methods Materials and Methods Laboratory work was conducted at the Agricultural Research Corporation (ARC), Wad Medani, Sudan during 2008-09. Trichogramma bouraracha, T. nerudai and Sitotroga cereallela were brought from AMW-Nützlinge Company (Germany), to Sudan in 2008 and 2009. Eight species of lepidopterous insect pests were selected either from storage such as, Sitotroga cerealella, Ephestia calidella and Corcyra cephalonica or from their host plants such as Helicoverpa armigera, Earias insulana, Trichoplusia ni , Spodoptera exigua and Sesamia cretica. These hosts were collected at different stages from the ARC research fields and reared in the laboratory under room temperature until the adults emerged and laying eggs. The papers containing eggs were cut to pieces (egg-cards) before offered to different numbers of T. bouraracha and T. nerudai separately in glass tubes (15 cm long × 3 cm Ø). A small drop of honey was added to each egg-card to provide a food for Trichogramma wasps. The parasitized eggs as well as the hatching adults were counted using a binocular microscope. The experiment was replicated three times (as average), the unhatch eggs were excluded, average parasitism, emergence rate and female % for tested Trichogramma / host was determined. Grain moth, Sitotroga cerealella Oliver Bollworm, Helicoverpa armigera Hub. Spiny bollworm, Earias insulana Boisd Cabbage looper, Trichoplusia ni Hub. Leafworm, Spodoptera exigua Hub Stem borer, Sesamia cretica Led. Results Results All the tested eggs of the pest insects were accepted by the host females of Trichogramma nerudai and T. bourarachae as showed in the results (Table and fig. 1). The highest average of emergence rates of both Trichogramma species were 2.68 and 2.02 respectively appeared from Sesamia cretica, while the storage pests (Ephestia calidella and Sitotroga cerealella) showed the lowest appearing for the both Trichogramma species (1.00 - 1.08) in compared to other tested host. The highest female percent was emerged from Corcyra cephalonica (T. nerudai and T. bourarachae, 82 % and 70 % respectively) and the lowest percent was emerged from E. calidella for both Trichogramma species (38 % and 21 % respectively). Helicoverpa armigera and Earias insulana showed similar female percent for both T. nerudai and T. bourarachae (Table and fig. 2). Trichogram m a sp. vrs Em ergence rate 0.0 1.0 2.0 3.0 Ses Hel Spo Ear Tri Cor Sit Eph Hosts Em erg en ce rate BOU NER Trichogram m a sp. vrs % Fem ale 0 20 40 60 80 100 Cor Sit Spo Ses Hel Ear Tri Eph Hosts % Fem ale BOU NER Figure 1: the emergence rate of T. nerudai and T. bourarachae from different host eggs Figure 2: the % female of T. nerudai and T. bourarachae emerging from different host eggs Parameter (Mean ± SD) Trichogramm a sp. Hosts Sitotroga cerealella Ephestia calidella Corcyra cephalonica Helicoverpa armigera Earias insulana Trichoplosia ni Spodoptera exigua Sesamia cretica Number of parasitized eggs T. nerudai 43.0 ± 33.98 10.67 ± 3.79 30.83 ± 21.39 34.25 ± 12.61 25.57 ± 8.68 9.5 ± 2.89 16.5 ± 10.85 20.0 ± 14.55 T. bourarachae 30.67 ± 14.19 15.75 ± 7.37 39.6 ± 14.15 32.4 ± 15.27 18.83 ± 7.81 9.75 ± 7.54 6.33 ± 3.79 22.33± 14.94 Number of Emerged adults T. nerudai 47.25± 38.42 11.33 ± 3.51 41.83±24. 73 62.75± 1.03 51.0±16.1 1 16.75± 8.85 33.0 ± 28.93 53.0 ± 37.94 T. bourarachae 32.67± 14.57 15.75 ± 7.37 49.6 ± 19.31 59.8± 31.50 30.83±21. 06 16 ± 17.36 9 ± 5.00 45 ± 35.44 Emergence rate T. nerudai 1.07 ± 0.13 1.07 ± 0.13 1.45 ± 0.26 1.96 ± 0.49 2.04 ± 0.49 1.77 ± 0.89 1.79 ± 0.59 2.68 ± 0.54 T. bourarachae 1.08 ± 0.08 1.00 ± 0.00 1.25 ± 0.15 1.82 ± 0.21 1.57 ± 0.72 1.42 ± 0.40 1.58 ± 0.52 2.02 ± 0.42 % Female T. nerudai 77 ± 0.05 38 ± 0.38 82 ± 0.09 64 ± 0.13 65 ± 0.11 73 ± 0.09 78 ± 0.14 73 ± 0.11 T. bourarachae 69 ± 0.02 21 ± 0.43 70 ± 0.16 66 ± 0.13 64± 0.09 60 ± 0.15 68 ± 0.21 67 ± 0.08 Date moth, Ephestia calidella Guen Rice moth, Corcyra cephalonica St. Table: the emergence rate and the female percentage of different host eggs parasitized by Trichogramma nerudai and T. bouraracha. SD = Standard deviation Conclusion and Recommendation Conclusion and Recommendation All the tested hosts showed the highest emergence rate compared with the storage pest, this difference in the emergence rate might be due to their egg size. More than 50 % females were emerged from all the tested host eggs except Ephestia calidella for both Trichogramma sp. . T. nerudai was found to be more fecund and fertile relative to T. bourarachae (high % female). So we recommend to involve the egg parasitoids Trichogramma within the strategy of IPM Program in Sudan.
description
Testing of the Egg Parasitoids Trichogramma bourarachae Pintureau and Trichogramma nerudai Pintureau against some Lepidopterous insect pests in Sudan. Sara A. A. Kehail and Hayder Abdelgader . Agricultural Research Corporation, Crop Protection Research Centre, P. O. Box 126 Wad Medani, Sudan. - PowerPoint PPT Presentation
Transcript of Sara A. A. Kehail and Hayder Abdelgader
Testing of the Egg Parasitoids Testing of the Egg Parasitoids Trichogramma bourarachae Trichogramma bourarachae Pintureau andPintureau and Trichogramma Trichogramma nerudai nerudai Pintureau against some Lepidopterous insect pests in SudanPintureau against some Lepidopterous insect pests in Sudan
Sara A. A. Kehail and Hayder Abdelgader Sara A. A. Kehail and Hayder Abdelgader Agricultural Research Corporation, Crop Protection Research Agricultural Research Corporation, Crop Protection Research
Centre, P. O. Box 126 Wad Medani, SudanCentre, P. O. Box 126 Wad Medani, Sudan
IntroductionIntroductionTrichogramma (Hymenoptera: Trichogrammatidae) are extremely tiny wasps, the female Trichogramma lay their eggs within a host eggs. Each female parasitizes from 10 to 190 eggs during its life. More than one parasite egg may be inserted into each host egg and this is based, on the egg size. After hatching, the parasitoid larvae feed on the contents of the host egg. The wasps pupate within the egg and adults chew an emergence hole to escape. There are several species and strains of Trichogramma, which vary considerably in their ability to control different insects and in their adaptation to different environmental conditions and crops. Trichogramma have been used as inundative biological control agents against a range of agricultural pests, mainly lepidopterans.
ObjectiveObjectiveThe current study was carried to test the acceptance of two Trichogramma species (Trichogramma bourarachae Pintureau; and Trichogramma nerudai Pintureau) against host eggs of different Lepidopterous insect pests in Sudan.
Trichogramma Wasp
A female Trichogramma wasp while laying her eggs inside a host egg
A Trichogramma wasp while emerging out of the parasitized egg
Materials and MethodsMaterials and MethodsLaboratory work was conducted at the Agricultural Research Corporation (ARC), Wad Medani, Sudan during 2008-09. Trichogramma bouraracha, T. nerudai and Sitotroga cereallela were brought from AMW-Nützlinge Company (Germany), to Sudan in 2008 and 2009. Eight species of lepidopterous insect pests were selected either from storage such as, Sitotroga cerealella, Ephestia calidella and Corcyra cephalonica or from their host plants such as Helicoverpa armigera, Earias insulana, Trichoplusia ni, Spodoptera exigua and Sesamia cretica. These hosts were collected at different stages from the ARC research fields and reared in the laboratory under room temperature until the adults emerged and laying eggs. The papers containing eggs were cut to pieces (egg-cards) before offered to different numbers of T. bouraracha and T. nerudai separately in glass tubes (15 cm long × 3 cm Ø). A small drop of honey was added to each egg-card to provide a food for Trichogramma wasps. The parasitized eggs as well as the hatching adults were counted using a binocular microscope. The experiment was replicated three times (as average), the unhatch eggs were excluded, average parasitism, emergence rate and female % for tested Trichogramma / host was determined.
Grain moth, Sitotroga cerealella Oliver
Bollworm, Helicoverpa armigera Hub.
Spiny bollworm, Earias insulana Boisd
Cabbage looper, Trichoplusia ni Hub.
Leafworm, Spodoptera exigua Hub
Stem borer, Sesamia cretica Led.
ResultsResultsAll the tested eggs of the pest insects were accepted by the host females of Trichogramma nerudai and T. bourarachae as showed in the results (Table and
fig. 1). The highest average of emergence rates of both Trichogramma species were 2.68 and 2.02 respectively appeared from Sesamia cretica, while the storage pests (Ephestia calidella and Sitotroga cerealella) showed the lowest appearing for the both Trichogramma species (1.00 - 1.08) in compared to other tested host. The highest female percent was emerged from Corcyra cephalonica (T. nerudai and T. bourarachae, 82 % and 70 % respectively) and
the lowest percent was emerged from E. calidella for both Trichogramma species (38 % and 21 % respectively). Helicoverpa armigera and Earias insulana showed similar female percent for both T. nerudai and T. bourarachae (Table and fig. 2).
Trichogramma sp. vrs Emergence rate
0.0
1.0
2.0
3.0
Ses Hel Spo Ear Tri Cor Sit EphHosts
Emer
genc
e ra
te
BOU
NER
Trichogramma sp. vrs % Female
0
20
40
60
80
100
Cor Sit Spo Ses Hel Ear Tri EphHosts
% F
emal
e
BOU
NER
Figure 1: the emergence rate of T. nerudai and T. bourarachae from different host eggs
Figure 2: the % female of T. nerudai and T. bourarachae emerging from different host eggs
Parameter (Mean ± SD)
Trichogramma sp.
HostsSitotroga cerealella Ephestia
calidella
Corcyra cephalonica
Helicoverpa
armigera
Earias
insulana
Trichoplosia
ni
Spodoptera
exigua
Sesamia
cretica
Number of parasitized eggs
T. nerudai 43.0 ± 33.98 10.67 ± 3.79 30.83 ± 21.39 34.25 ± 12.61 25.57 ± 8.68 9.5 ± 2.89 16.5 ± 10.85 20.0 ± 14.55
T. bourarachae 30.67 ± 14.19 15.75 ± 7.37 39.6 ± 14.15 32.4 ± 15.27 18.83 ± 7.81 9.75 ± 7.54 6.33 ± 3.79 22.33± 14.94
Number of Emerged adults
T. nerudai 47.25± 38.42 11.33 ± 3.51 41.83±24.73 62.75± 1.03 51.0±16.11 16.75± 8.85 33.0 ± 28.93 53.0 ± 37.94
T. bourarachae 32.67± 14.57 15.75 ± 7.37 49.6 ± 19.31 59.8± 31.50 30.83±21.06 16 ± 17.36 9 ± 5.00 45 ± 35.44Emergence rate T. nerudai 1.07 ± 0.13 1.07 ± 0.13 1.45 ± 0.26 1.96 ± 0.49 2.04 ± 0.49 1.77 ± 0.89 1.79 ± 0.59 2.68 ± 0.54
T. bourarachae 1.08 ± 0.08 1.00 ± 0.00 1.25 ± 0.15 1.82 ± 0.21 1.57 ± 0.72 1.42 ± 0.40 1.58 ± 0.52 2.02 ± 0.42% Female T. nerudai 77 ± 0.05 38 ± 0.38 82 ± 0.09 64 ± 0.13 65 ± 0.11 73 ± 0.09 78 ± 0.14 73 ± 0.11
T. bourarachae 69 ± 0.02 21 ± 0.43 70 ± 0.16 66 ± 0.13 64± 0.09 60 ± 0.15 68 ± 0.21 67 ± 0.08
Date moth, Ephestia calidella Guen
Rice moth, Corcyra cephalonica St.
Table: the emergence rate and the female percentage of different host eggs parasitized by Trichogramma nerudai and T. bouraracha.
SD = Standard deviation
Conclusion and RecommendationConclusion and RecommendationAll the tested hosts showed the highest emergence rate compared with the storage pest, this difference in the emergence rate might be due to their egg size. More than 50 % females were emerged from all the tested host eggs except Ephestia calidella for both Trichogramma sp.. T. nerudai was found to be more fecund and fertile relative to T. bourarachae (high % female). So we recommend to involve the egg parasitoids Trichogramma within the strategy of IPM Program in Sudan.
