Antifeedant activity and phytochemical investigation of Millettia pachycarpa extracts against Tobacco Leaf Eating Caterpillar, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae)

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.

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Interaction of entomopathogenic nematodes,Steinernema glaseri(Rhabditida: Steinernematidae), cultured in irradiated hosts, with ‘F1sterility’: Towards management of a tropical pest,Spodoptera litura(Fabr.) (Lepidoptera: Noctuidae)

Biocontrol Science and Technology ◽

10.1080/09583150902814515 ◽

2009 ◽

Vol 19 (sup1) ◽

pp. 139-155 ◽

Cited By ~ 6

Author(s):

Rakesh K. Seth ◽

Tapan K. Barik ◽

Sonal Chauhan

Keyword(s):

Spodoptera Litura ◽

Entomopathogenic Nematodes ◽

Steinernema Glaseri ◽

Lepidoptera Noctuidae

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Triterpenes induced by young apple fruits in response to herbivore attack

Bioscience Biotechnology and Biochemistry ◽

10.1093/bbb/zbab077 ◽

2021 ◽

Author(s):

Yuto Ohata ◽

Yuuki Tetsumoto ◽

Sayo Morita ◽

Naoki Mori ◽

Yoichi Ishiguri ◽

...

Keyword(s):

Malus Domestica ◽

Spodoptera Litura ◽

Mechanical Damage ◽

Antifeedant Activity ◽

Varietal Differences ◽

Triterpene Acids ◽

Lepidopteran Insect ◽

Pest Insects ◽

Herbivore Attack ◽

Apple Fruits

Abstract Apples Malus domestica, known as a rich source of triterpene acids, induced more variety and quantity of triterpene acids in response to herbivory or mechanical damage. There were three major induced compounds: pomaceic acid and euscaphic acid, both of which are known apple triterpene acids, and 2α,19α-dihydroxy-3-oxours-12-en-28-oic acid (named eriobotoric acid), which was first identified in apples. In this study, the three compounds’ induction curves after damage, varietal differences in induction amounts, and physiological roles against pest insects were further investigated. Eriobotoric acid showed clear antifeedant activity against lepidopteran insect Spodoptera litura but not against apple pests.

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