Effect of sweet flag rhizome oil (Acorus calamus) on hemogram and ultrastructure of hemocytes of the tobacco armyworm, Spodoptera litura (Lepidoptera: Noctuidae)

Micron ◽  
2008 ◽  
Vol 39 (5) ◽  
pp. 544-551 ◽  
Author(s):  
Parduman R. Sharma ◽  
Om P. Sharma ◽  
Bhaskar P. Saxena
Author(s):  
Phatcharaphon Wiwattanawanichakun ◽  
Siriwan Saehlee ◽  
Thitaree Yooboon ◽  
Nutchaya Kumrungsee ◽  
Saksit Nobsathian ◽  
...  

Abstract Background Spodoptera litura (Lepidoptera: Noctuidae), the tobacco cutworm, is an prominent agricultural pest. To reduce the use of chemical pesticides that cause health problems and that leave residue in the environment, some botanical pesticides have been developed. Our research aimed to evaluate the insecticidal efficacy of Acorus calamus L. extract for the control of S. litura under laboratory conditions. Results After 24 h of topical application, the A. calamus methanolic crude extract showed toxicity against secondary instar S. litura larvae (LD50 ~ 7.438 µg/larva). Chrysin (5,7-dihydroxy flavone), one of the isolated phenolic compounds, showed optimal control efficiency (LD50 ~ 2.752 µg/larva) and showed a reduction in carboxylesterase activities, which have detoxification reduction roles in larvae. Conclusion Chrysin in the crude extract of A. calamus may be an active compound to control this pest, and it may be applied as an alternative to minimize the usage of chemical insecticides. Graphical Abstract


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Gurmehar Kaur Grewal ◽  
Neelam Joshi ◽  
Yadhu Suneja

Abstract Background Spodoptera litura (Fab.) (Lepidoptera: Noctuidae) is a serious agricultural pest that infests many commercially important crops of Southeast Asian countries. Indiscriminate use of chemical pesticides has led to various health hazards as well as insecticide resistance. Entomopathogenic fungi (EPF) provide an important alternative as biological control agents. Metarhizium rileyi is an EPF with a specific host range for lepidopteran pests. The present study aimed to identify virulent M. rileyi isolate against S. litura larvae and analyse their extracellular cuticle-degrading enzyme activities. Results Three M. rileyi isolates viz M. rileyi NIPHM, M. rileyi MTCC 4254 and M. rileyi MTCC 10395 formulations were evaluated at different concentrations against 2nd instar larvae of S. litura. A maximum percent mortality of 63.33% was recorded in M. rileyi NIPHM (12 g/l), followed by M. rileyi MTCC 4254 (58.33%) at the same concentration, 10 days post-treatment. Maximum means of chitinase, protease and lipase activities (0.44, 1.58 and 2.95 U/ml, respectively) were recorded in the case of M. rileyi NIPHM. Correlation analysis was positive between enzyme activity and larval mortality. Conclusions Metarhizium rileyi NIPHM recorded the highest enzymatic activity and exhibited the maximum mortality rate against 2nd instar larvae of S. litura, suggesting the possible role of these enzymes in the pathogenicity of the fungus. Further knowledge in this regard may help in the development of enzyme-based screening methods for selecting virulent fungal isolates for the eco-friendly management of crop pests.


2017 ◽  
Vol 25 (11) ◽  
pp. 10383-10391 ◽  
Author(s):  
Giovanni Benelli ◽  
Marimuthu Govindarajan ◽  
Mohamad S. AlSalhi ◽  
Sandhanasamy Devanesan ◽  
Filippo Maggi

2019 ◽  
Vol 112 (5) ◽  
pp. 2167-2176 ◽  
Author(s):  
Torranis Ruttanaphan ◽  
Wanchai Pluempanupat ◽  
Chutikan Aungsirisawat ◽  
Polnarong Boonyarit ◽  
Gaelle Le Goff ◽  
...  

Abstract Essential oils are well known to act as biopesticides. This research evaluated the acute toxicity and synergistic effect of essential oil compounds in combination with cypermethrin against Spodoptera litura Fabricius (Lepidoptera: Noctuidae). The effects of distillation extracts of essential oils from Alpinia galanga Zingiberaceae (Zingiberales) rhizomes and Ocimum basilicum Lamiaceae (Lamiales) leaves; one of their primary essential oil compounds 1,8-cineole; and linalool were studied on second-instar S. litura by topical application under laboratory conditions. The results showed that A. galanga had the highest control efficiency, whereas1,8-cineole provided a moderate efficacy. The mixtures of linalool, 1,8-cineole, O. basilicum, or A. galanga with cypermethrin were synergistic on mortality. Activity measurements of the main detoxification enzymes show that linalool and 1,8-cineole inhibit the activity of cytochromes P450 and carboxylesterases, which could explain their synergistic effect. Based on our results, the use of these mixtures represents an ideal eco-friendly approach, helping to manage cypermethrin resistance of S. litura.


2017 ◽  
Vol 56 ◽  
pp. 76-85 ◽  
Author(s):  
Subramanian P. Subala ◽  
Eduardo E. Zubero ◽  
Moises A. Alatorre-Jimenez ◽  
Muthugounder S. Shivakumar

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