Evaluation of Ethiopian Entomopathogenic Fungi Isolates Against the Two-Spotted Spider Mite, Tetranychus urticae Koch on Tomato, Solanum lycopersicum L.
Gelana Keno,
Belay Habtegebriel,
Ferdu Azerefegne
Issue:
Volume 5, Issue 2, June 2022
Pages:
11-19
Received:
22 March 2022
Accepted:
21 April 2022
Published:
28 April 2022
DOI:
10.11648/j.ajz.20220502.11
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Abstract: Two spotted spidermite (TSSM), Tetranychus urticae (Koch, 1836) is economically important in greenhouse grown tomato in Ethiopia. This study entomopathogenic fungi (EPF) such as Metarhizium anisopliae (Metschnikoff, 1883) and Beauveria bassiana (Balsamo, 1912) isolates evaluated for the management of the two spotted spider mites under both laboratory and glasshouse controlled environmental conditions. Six fungal newly isolated from the soil and one existing isolate were evaluated and identified in the laboratory for virulence against T. urticae. Spore dilutions were prepared in 0.01% Tween 80. Adults and eggs were sprayed with 1 ml of conidial suspension adjusted to 1×108 conidia/ml. The mites those treated were kept under controlled conditions at 25°C and 60–70% RH and the number of dead mites was recorded daily on tomato leaf. All the isolates tested were infected and killed adults and eggs of spider mites at a concentration of 1×108 conidia ml-1 after eight and seven days respectively, but had varying virulence on adults ranged from 33% to 93% and on egg ranged from 32% to 87%. Two B. bassiana isolates, GF3 and 9604, which resulted in 93% and 85% mortality of adults 8 days post inoculation, respectively were categorized as highly virulent whereas M. anisopliae MF3 and AF5 which resulted in 64% and 54% mortality were considered as moderately virulent isolates. Similarly, B. bassiana AF2, BF4 and KF3 which resulted in mortality of 47%, 36% and 33%, respectively, were considered as weak isolates against the two spotted spider mites. The highly virulent isolates were further evaluated under glasshouse condition on potted tomato plants for their virulence against T. urticae. Isolate GF3 caused the highest mortality (78%) followed by 9604 which caused 70% mortality after seven days of inoculation. From this study the native M. anisopliae and B. bassiana isolates have potential to kill the TSSM both eggs and adults’ stages of the pest. Thus why, EPF isolates can be used as an alternative to chemical treatments.
Abstract: Two spotted spidermite (TSSM), Tetranychus urticae (Koch, 1836) is economically important in greenhouse grown tomato in Ethiopia. This study entomopathogenic fungi (EPF) such as Metarhizium anisopliae (Metschnikoff, 1883) and Beauveria bassiana (Balsamo, 1912) isolates evaluated for the management of the two spotted spider mites under both laborato...
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The First Report of an Unusual Freshwater Crayfish (Astacus leptodactylus) in Aras Dam of Iran - A Case Study
Masoud Seidgar,
Saber Shiri,
Ali Nekouiefard,
Ali Reza Valipour,
Feriedun Mohebbi
Issue:
Volume 5, Issue 2, June 2022
Pages:
20-23
Received:
29 March 2022
Accepted:
3 May 2022
Published:
12 May 2022
DOI:
10.11648/j.ajz.20220502.12
Downloads:
Views:
Abstract: Aras is one of the largest rivers in northwest Iran and Caspian sea basin. Aras dam reservoir with max capacity = 1350 × 106 m3, max area = 153 km2, mean depth = 20 m and height = 36 m was established on this river in 1972. It is one of the most important inland water fish stocks and aquaculture resources in Iran. More than 700 people working on two cooperative fisheries companies in the area. Freshwater crayfish (Astacus leptodactylus) of Aras Dam is of a great interest in Europe as a luxury and delicious food. The purpose of the present study was to distinguish an unusual morphological abnormality in freshwater crayfish forks and its probable causes. The results of this research were obtained during the crayfish study project aiming to assess stock and biological status in Aras Dam Reservoir in 2016. Crayfishes caught with funeral and foldable traps and the biometery and morphological characteristics of specimens were measured in laboratory. This is the first report of the unusual growth of freshwater crayfish (Astacus leptodactylus) fork in Aras Dam. A male crayfish was caught with a total length of 153mm and weighing 154 g had a fork length of 190 mm with 7 left finger straps. The probable cause can be attributed to any small lesions created in the ligaments (wound, amputation), stimulation to growth (reconstruction) of additional ligaments.
Abstract: Aras is one of the largest rivers in northwest Iran and Caspian sea basin. Aras dam reservoir with max capacity = 1350 × 106 m3, max area = 153 km2, mean depth = 20 m and height = 36 m was established on this river in 1972. It is one of the most important inland water fish stocks and aquaculture resources in Iran. More than 700 people working on tw...
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