Molecular and Morphological characterization of multiple nucleopolyhedrovirus from Mexico and their insecticidal activity against
            Spodoptera frugiperda
            (Lepidoptera: Noctuidae)

Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae) is a polyphagous insect pest native to America. Due to its capacity for adaptation and migration, it is currently located in Africa, Asia, and Oceania, where it threatens agricultural crops. The ability of S. frugiperda to develop resistance to insecticides is one of the reasons for the continuous search for more effective, low-cost, and environmentally friendly control products. In the present work, the insecticidal activity of ethanolic and hexane extracts obtained from fresh and dehydrated leaves of Piper auritum Kunth (Piperales: Piperaceae), Piper umbellatum L. (Piperales: Piperaceae), and Cedrela odorata L. (Sapindales: Meliaceae) was studied against first instar larvae of S. frugiperda. The ethanolic extracts of the dehydrated leaves of C. odorata and P. auritum presented insecticidal activity as high (100% mortality at a concentration of 92 mg/cm2) as that obtained with the positive control, Melia azedarach L. (Sapindales: Meliaceae). The GC-MS analysis of the extracts revealed the presence of phytochemicals classified mainly into the groups of monoterpenes, sesquiterpenes, diterpenes, phenylpropanoids, alcohols, and fatty acids. P. auritum grows and propagates rapidly. In addition, due to its low toxicity in mammals and non-target insects, it is a plant with the potential to be used as a botanical insecticide. The exposure of S. frugiperda larvae to low concentrations of ethanolic extract of P. auritum allowed us to observe their biological activity in the development of this insect. The LC50 was 22.1 mg/cm2. At sublethal concentrations (LC21 and LC35) the low fertility of the emerging adults was noticeable.

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Bacillus thuringiensis survey in Brazil: geographical distribution and insecticidal activity against Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

Neotropical Entomology ◽

10.1590/s1519-566x2003000400014 ◽

2003 ◽

Vol 32 (4) ◽

Cited By ~ 22

Author(s):

Fernando H. Valicente ◽

Marliton R. Barreto

Keyword(s):

Bacillus Thuringiensis ◽

Geographical Distribution ◽

Insecticidal Activity ◽

Spodoptera Frugiperda ◽

Lepidoptera Noctuidae

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Molecular and Biological Characterization of Spodoptera frugiperda Multiple Nucleopolyhedrovirus Field Isolate and Genotypes from China

Insects ◽

10.3390/insects11110777 ◽

2020 ◽

Vol 11 (11) ◽

pp. 777

Author(s):

Chengfeng Lei ◽

Jian Yang ◽

Jia Wang ◽

Jia Hu ◽

Xiulian Sun

Keyword(s):

Spodoptera Frugiperda ◽

Field Isolate ◽

Management Strategies ◽

Fall Armyworm ◽

Multiple Nucleopolyhedrovirus ◽

Cloning Method ◽

Occlusion Bodies ◽

Colombian Isolate

The fall armyworm, Spodoptera frugiperda, is a new invading pest in China. The baculovirus Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) is a pathogenic agent of the fall armyworm and a potential agent for its control in integrated pest management strategies. In this work, we analyze the molecular and biological characteristics of an SfMNPV isolate collected from maize in China (SfMNPV-Hub). Two genotypes were further isolated from SfMNPV-Hub by an in vivo cloning method. The PstI profile of one genotype (SfHub-A) was similar to genotype A of the SfMNPV Colombian isolate, and the other (SfHub-E) was similar to genotype E of the Colombian isolate. The bioactivity of SfHub-A against second-instar S. frugiperda larvae was not significantly different from that of SfMNPV-Hub, whereas SfHub-E was 2.7–5.5 fold less potent than SfMNPV-Hub. The speed of kill of SfHub-E was quicker than SfMNPV-Hub, while SfHub-A acted slower than SfMNPV-Hub. Occlusion body (OB) production of SfHub-A in an S. frugiperda cadaver was significantly higher than that of SfMNPV-Hub, while SfHub-E yielded far fewer occlusion bodies (OBs) in the host larvae. These results provide basic information for developing a virus-based pesticide against the invading pest S. frugiperda.

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