scholarly journals Effect of gallic acid on the larvae of Spodoptera litura and its parasitoid Bracon hebetor

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Abhay Punia ◽  
Nalini Singh Chauhan ◽  
Drishtant Singh ◽  
Anup Kumar Kesavan ◽  
Sanehdeep Kaur ◽  
...  

AbstractThe antibiosis effect of gallic acid on Spodoptera litura F. (Lepidoptera: Noctuidae) and its parasitoid evaluated by feeding six days old larvae on artificial diet incorporated with different concentrations (5 ppm, 25 ppm, 125 ppm, 625 ppm, 3125 ppm) of the phenolic compound revealed higher concentration (LC50) of gallic acid had a negative impact on the survival and physiology of S. litura and its parasitoid Bracon hebetor (Say) (Hymenoptera:Braconidae). The mortality of S. litura larvae was increased whereas adult emergence declined with increasing concentration of gallic acid. The developmental period was delayed significantly and all the nutritional indices were reduced significantly with increase in concentration. Higher concentration (LC50) of gallic acid adversely affected egg hatching, larval mortality, adult emergence and total development period of B. hebetor. At lower concentration (LC30) the effect on B. hebetor adults and larvae was non-significant with respect to control. Gene expression for the enzymes viz., Superoxide dismutase, Glutathione peroxidase, Peroxidase, Esterases and Glutathione S transferases increased while the total hemocyte count of S. litura larvae decreased with treatment. Our findings suggest that gallic acid even at lower concentration (LC30) can impair the growth of S. litura larvae without causing any significant harm to its parasitoid B. hebetor and has immense potential to be used as biopesticides.

2019 ◽  
Vol 11 ◽  
pp. 117954331986711 ◽  
Author(s):  
Muhammad Irfan Ullah ◽  
Nimra Altaf ◽  
Muhammad Afzal ◽  
Muhammad Arshad ◽  
Naunain Mehmood ◽  
...  

Entomopathogenic fungi (EPFs), Isaria fumosorosea and Beauveria bassiana, are efficient biological agents in the management of multiple arthropod pests. In this study, the effects of both EPF species on various life stages of Spodoptera litura (F.) (Lepidoptera: Noctuidae) and its natural enemy Rhynocoris marginatus (Fab.) (Hemiptera: Reduviidae) were determined under laboratory conditions. I. fumosorosea significantly ( P < .05) reduced the growth rate of the third and fourth instar larvae of S. litura. For relative consumption rate (RCR), the maximum impact was recorded for I. fumosorosea, which reduced the RCR of the larvae. The larvae of S. litura treated with I. fumosorosea showed significantly lower efficiency of conversion of ingested food (ECI) and the larval mortality rate (58.0%) was also higher compared with B. bassiana (33.3%). Similarly, I. fumosorosea had a significant effect on the pupal formation of S. litura; however, no significant effect was found on adult emergence percentage. To determine the effect of EPF-infected prey on the adult predator, their handling time, predatory rate, consumption rate, and the survival rate were recorded. No significant effect of EPF species on the predation rate was found. Furthermore, no significant difference was found in the survival rate of predators fed on either EPF-infected prey or healthy larvae. The interaction of these EPFs with a reduviid predator suggested that both EPF species, especially I. fumosorosea, could be used together with the predator to boost the biological control of S. litura in commercial crops.


1968 ◽  
Vol 58 (1) ◽  
pp. 1-24 ◽  
Author(s):  
J. R. Linley

Studies were carried out in Jamaica on the larval biology of Leptoconops becquaerti (Kieff.) in 1962–63.Larvae were reared on natural breeding sites in chambers constructed from large tins, by methods that are described in detail. The features of the breeding sites are illustrated and briefly discussed.The developmental period from egg hatching to adult emergence probably occupies four to eight weeks, depending to a certain extent upon temperature and hence on time of year. It is unlikely that the adult stage is ever reached in much less than three weeks under natural conditions. Under experimental conditions, overall survival to the adult stage was frequently greater than 20 per cent., and occasionally over 50 per cent. It is considered that survival in natural populations is probably also quite high.Larval mortality in the experimental chambers apparently occurred maintly in the first instar, and this probably happens in nature. The results showed a relationship between percentage survival and egg number such that proportionately fewer adults were obtained from chambers with greater numbers of eggs. This was interpreted as being due to progressively more severe starvation of very young larvae in the more crowded chambers.There was no marked tendency for adults of the more same sex to emerge first in the chambers. The sex ratio among the total of 1,039 adults obtained was 1:1.In an experiment to investigate the diel rhythm of adult emergence, 71 per cent. of adults of L. becquaerti emerged in the four-hour period of 0300–0700 hr., and a further 27 per cent. appered between 0700–1100 hr. This is earlier than found in Culicoides furcns (Poey) in a previous experiment.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Ghulam Sarwar ◽  
Naeem Arshad Maan ◽  
Muhammad Ahsin Ayub ◽  
Muhammad Rafiq Shahid ◽  
Mubasher Ahmad Malik ◽  
...  

Abstract Background The armyworms, Spodoptera exigua (Hübner), and S. litura (Fabricius) (Lepidoptera: Noctuidae) are polyphagous pests of many cash crops. Heavy crop losses have been reported for the fruit and vegetable crops each year owing to the diverse impact on global economies. The present study was aimed to sort out a novel method of pest control using the insect’s own nucleopolyhedrosis virus (NPV) alone and in combination with a new chemistry insecticide chlorantraniliprole. Results In the study, the effect of indigenous isolated nucleopolyhedrovirus (NPV) and the chemical insecticide (chlorantraniliprole) formulations against the 2nd and 4th larval instars of S. litura and S. exigua, collected from the different geographical region of Punjab (Pakistan) province, was evaluated. Three concentrations of the NPV isolate, sub-lethal (1 × 104, 6 × 104 POB ml−1), lethal (3 × 105 POB ml−1), and chlorantraniliprole 0.01 μl l−1, were applied alone and in combination against the 2nd and 4th larval instars of both pest species. The lethal concentration of NPV + chlorantraniliprole exhibited synergistic interaction and caused high larval mortality against both instars, while in all other combinations, additive effect was observed. Moreover, NPV + chlorantraniliprole at lethal concentration exhibited decreased pupation, adult emergence, and egg eclosion. Conclusion The implications of using NPV alone and in combination with an insecticide are discussed briefly in this study.


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.


Author(s):  
Mervat A. Kandil ◽  
Hemat Z. Moustafa

Abstract Background Cotton bollworms such as Pectinophora gossypiella and Earias insulana are serious pests which destroy the cotton plant, and Bracon brevicornis is a parasitoid which attacked the larvae of bollworms. Results In this study, experiments were performed to investigate and evaluate the toxicity of etofenprox and chlorpyrifos insecticides against newly hatched larvae of Pectinophora gossypiella and Earias insulana. Some biological aspects of compound effects on larval and pupal duration, percentage of mortality, and percentage of adult emergence which resulted from treated newly hatched larvae were studied. The results revealed that LC50 was 0.7 and 0.87 ppm when P. gossypiella was treated with etofenprox and chlorpyrifos, respectively, while LC50 was 0.09 and 0.73 ppm when E. insulana was treated with etofenprox and chlorpyrifos, respectively. The obtained results showed that the percentage of mean larval mortality was 65.0 and 63.0% for treated P. gossypiella, while it was 71.0 and 66.0% for treated E. insulana. The corresponding figure for pupal percentage mortality was 8.0 and 10.0% for treated P. gossypiella, but it was 5.0 and 2.0% for treated E. insulana, with etofenprox and chlorpyrifos, and a prolongation effect in larval and pupal development (total immature stage) resulted from treated both bollworms as follows: 35.5 and 32.4 days for treated P. gossypiella compared with 21.9 days in control and 34.7 and 23.2 days for treated E. insulana compared with 23.1 days in control. The indirect effect of etofenprox and chlorpyrifos on the total immature stage of Bracon brevicornis was 18.2 and 19.5 days compared with 14.3 days in control when B. brevicornis parasitized on P. gossypiella larvae while it was 19.8 and 20.6 days compared with 15.2 days when B. brevicornis parasitized on E. insulana larvae. Conclusion The life cycle of B. brevicornis after parasitism on P. gossypiella and E. insulana larvae treated with etofenprox and chlorpyrifos were increased than the control larvae.


Author(s):  
Eman Mohammed Abd-ElAzeem ◽  
Warda Ahmed Zaki El-Medany ◽  
Hend Mohammed Sabry

AbstractBiological activities of spores and metabolites of some fungi isolated from dead larva of the spiny bollworms (SBW), Earias insulana (Boisd.) (Lepidoptera: Noctuidae), against the newly hatched larvae of the pest were carried out. Results showed that the fungi Metarhizium anisopliae, Acremonium sp., and Paecilomyces variotii had affected the newly hatched larvae of (SBW). Acremonium sp. was the most potent one as it had the highest newly hatched larval mortality percentage (65 and 58.33%) for its spore suspension and metabolites, respectively, while the lowest one (41%) was for P. variotii metabolites. Also, spore suspensions of the all fungal isolates had the highest larval mortality than fungal metabolites. Studying the enzymatic activity showed that Acremonium sp. produced protease enzyme on media containing gelatin, which caused the highest larval mortality (72.22%).These isolates showed different effects on all stages of the pest and decreased pupal weight, adult emergence percentages, deposited eggs, and hatchability percentages than the control. Identification of Acremonium sp. EZ1 was confirmed using 18 s rRNA and its accession number MN25101.


2019 ◽  
Vol 4 (1) ◽  
pp. 28
Author(s):  
Kartina Kartina ◽  
Shulkipli Shulkipli ◽  
Mardhiana Mardhiana ◽  
Saat Egra

<h1>Spodoptera litura F. is one of the important pests in Horticulture commodities which can cause damage 80% and up to 100%. Karamunting (Melastome malabathricum) is a wild plant that grows in Tarakan City. This plant is known to contain secondary metabolites which are thought to have the potential to control pests. This study aims to determine the potential of Karamunting extract as a botanical insecticide material to control armyworms. This study uses a completely randomized design (CRD) method with 1 treatment factor, namely the concentration of Karamunting leaf extract. Potential extracts as botanical insecticides were tested by dye method using 4 concentrations, namely 0 (control); 500; 1000; 2000; 4000; and 8000 ppm. The results showed that Karamunting leaf extract was able to control armyworm pests. Giving extracts of 8000 ppm (P5) in feed caused the highest decrease in eating activity up to 41,2%, larval mortality up to 85%, and the highest mortality rate after 7 days of observation. Decreased feeding activity and larval mortality were thought to be influenced by the presence of phenol compounds, fatty acids, terpenoids, sterols and alkaloids identified in the extract. Thus, Karamunting leaf extract has the potential to be developed as an active ingredient in botanical insecticides to control armyworm.<strong></strong></h1>


Author(s):  
Sayed M S Khalil ◽  
Kashif Munawar ◽  
Azzam M Alahmed ◽  
Ahmed M A Mohammed

Abstract Culex quinquefasciatus, a member of the Culex pipiens complex, is widespread in Saudi Arabia and other parts of the world. It is a vector for lymphatic filariasis, Rift Valley fever, and West Nile virus. Studies have shown the deleterious effect of RNA interference (RNAi)-mediated knockdown of various lethal genes in model and agricultural pest insects. RNAi was proposed as a tool for mosquito control with a focus on Aedes aegypti and Anopheles gambiae. In this study, we examined the effect of RNAi of selected target genes on both larval mortality and adult emergence of Cx. quinquefasciatus through two delivery methods: soaking and nanoparticles. Ten candidate genes were selected for RNAi based on their known lethal effect in other insects. Disruption of three genes, chitin synthase-1, inhibitor of apoptosis 1, and vacuolar adenosine triphosphatase, resulted in the highest mortality among the selected genes using the two treatment methods. Silencing the other seven genes resulted in a medium to low mortality in both assays. These three genes are also active against a wide range of insects and could be used for RNAi-based mosquito control in the future.


2019 ◽  
Vol 49 (1) ◽  
pp. 59-65 ◽  
Author(s):  
Holly Hooper ◽  
Matthew J Grieshop

Abstract The arrival of spotted wing Drosophila, Drosophila suzukii (Matsumura), to the United States has caused many berry and cherry growers to replace IPM programs with calendar-based broad-spectrum insecticide programs. Alternative management tactics are urgently needed to mitigate the current dependency on chemical control. Postharvest burial is a cultural crop sanitation strategy that has the potential to reduce D. suzukii reproductive habitat and eliminate infested fruit wastes. This study revealed that D. suzukii rarely pupate on the soil’s surface or below 1 cm, but are capable of unburying themselves from depths up to 48 cm. Although zero emergence was not obtained in the field, adult emergence decreased exponentially with deeper burial depths. A burial depth of 24 cm reduced D. suzukii emergence by 97%, although soil texture may influence this optimal burial depth. Soils that had a higher concentration of sand had a negative impact on D. suzukii survival at shallower burial depths. The mechanism behind the reduction in adult emergence from differing burial depths remains unclear as the lipid concentration between emerging D. suzukii was the same regardless of burial depth.


Pathogens ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 986
Author(s):  
Benta Natânia Silva Figueiredo ◽  
Marcello Otake Sato ◽  
Laiane Teixeira Sousa Moura ◽  
Sandra Maria Botelho Mariano ◽  
Tarso da Costa Alvim ◽  
...  

The current study evaluated the anthelmintic effect of different extracts of Leucaena leucocephala, Parkia platycephala, and Senna alata on trichostrongylid eggs and infective larvae and determined the potential active components of each plant. Dried and macerated plant material was concentrated using rotaevaporation to obtain the crude extract (CE), followed by solvent partitioning to obtain hexanic (HexE), acetatic (AcE), and butanolic (BuE) extracts used for phytochemical analysis and anthelmintic efficacy testing in vitro. All the crude and partitioned extracts tested showed inhibition activity in the hatching of trichostrongylid eggs. Larvicidal efficacy was observed at CE concentrations of 2.5, 5.0, and 7.5 mg/mL for P. platycephala and S. alata. However, L. leucocephala CE did not significantly reduce the number of living larvae in the tested concentrations. Chromatographic analysis revealed several active metabolites; gallic acid, ellagic acid, naringin, morin, and kaempferol on AcE of P. platycephala; gallic acid, rutin, and ellagic acid on BuE of P. platycephala; and gallic acid and naringin on BuE of L. leucocephala. The extracts of P. platycephala, L. leucocephala, and S. alata leaves showed egg hatching inhibition and larvicidal activity, probably produced by tannins and flavonoids, which may act alone or by synergism.


Sign in / Sign up

Export Citation Format

Share Document