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Evaluating the efficiency of certain Coccinellides predatory insects against some greenhouses pests
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Abstract: The present studies were carried out in two greenhouses belonging to the Economic Entomology Department, Faculty of Agriculture, Mansoura University, during the two successive growing seasons 1994/95 and 1995/96 on both vegetable crops squash and cucumber. The aim of the work was to study the population density of major insect pests infesting both crops as well as their associated predatory insects. In addition, certain biological characters of the predator C. sptempunctata were also studied when fed either on different aphid species (natural preys) or artificial diet. The investigation likewise covered an evaluation the role of C. sptempunctata in controlling the major injurious insects on these two vegetable crops in greenhouses.
The resu_Cts .o6t_ained couff 6e summ-arize_das f_o_C_Cows: I- Survey studies:
Squash and cucumber crop
1- Six injurious insect species were found infesting this crop. These species belong to three orders namely:
Homoptera, Thysanoptera and Collembola. The homopterous insects were the most dominant in the two seasons of study. The recorded homopterous species were :
A. gossypii; B. tabaci; E. lybica and E. discipiens.
2- Nine predatory insect species were recorded on squash plantation in greenhouses. These species are members of the two orders, Coleoptera and Dermaptera. The dominant species were, C. undecimpunctata, P. alfierii, Cy. vicina isis, Cy. vicina nilotica, S. syriacus and S. interruptus.
II- Results of biological studies of the predator C. septempunctata:
A- On natural preys (Aphids):
The larval and adult stages of the predator, C. septemp.unctata were reared on the three aphids, A. gossypii; A. craccivora and M. pisi.
The averages durations of the predator larval stages were, 10.2±0.52, 12.65±0.48; 8.7±0.98 days on the three aphids, successively. The respective pupal periods were 4.05±0.39; 4.6±0.50; 5.5±0.68 days.
The male longevity was 60.55±2.0, 85.83±2.97 and 32.31±4.2 days on the three preys, in succession, while the female longevity was 68.77±3.4, 91.0±2.5 and 37.85± 1.77 days. The fecundity was 504±23.1, 878±4.84 and 637± 43.1 eggs when the females were fed on the three aphids, respectively.
(B- On -the artificial diet:
The average duration of C. septempunctata larval stage was 16.16±0.51 days, while the average pupal stage was 5.5±0.51 days.
The average longevity of the male was 130.16±18.9 days, while the longevity of the female was 143.5±3.22 days. The fecundity of the female on artificial diet fell to an average of 101.25±14.7 eggs.
III- The role of C. septempunctata in controlling injurious insects on vegetable crops in the greenhouse:
The results of application of the predator C. septempunctata in greenhouses by adding the required numbers to justify the predator: prey ratio to be within the limits 1:10 (the critical value), assured their efficiency in maintaining the population density of injurious insects under the economic injury level on both experimental crops.
From the results. of this study the use of C. septempunctata could be recommended for controlling injurious insects on squash and cucumber in greenhouses, without the application of any insecticides.
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| Publication year |
1997
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| Availability location |
معهد بحوث وقاية النبات - ش نادى الصيد - الدقى - جيزة
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| Availability number |
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| Organization Name |
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| Country |
Egypt
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| Author(s) from ARC |
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| Agris Categories |
Protection of plants - General aspects
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AGROVOC
TERMS |
Coccinella septempunctata.
Efficiency.
Evaluation.
Greenhouses.
Pests of plants.
Predators.
Vegetable crops.
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| Publication Type |
Master Thesis
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