Management Of Fall Armyworm Research Articles

Fall Armyworm: Current Status in Nepal, its Management and Way Forward

Fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is an economically important invasive pest species primarily infesting maize. It is highly polyphagous and migratory in nature, posing a threat to several economically important crops. This pest has traveled a long journey from the American continent to Asia via Africa. This insect has inflicted substantial damage to Maize’s crop productivity of Maize in Nepal, since its introduction in May 2019 and has now become widespread from plain regions to hilly regions of the country. Therefore, this pest problem is considered a major issue for research and development in the country. The lessons from world research and development in the fall armyworm management could be adapted and used in Nepal after its proper validation. In order to identify the current status of fall armyworm in Nepal and the management of the insect species, we have discussed overviews on biology, ecology, origin and distribution pathway, management, and way forward, focusing on sustainable measures which could be useful for designing integrated pest management of fall armyworm in Nepal since knowledge gap is large.

Management of Fall Army Worm of Maize, Spodoptera frugiperda, with Green Synthesis Silver Nanoparticles

The fall armyworm (FAW), Spodoptera frugiperda is a polyphagous and economically important insect pest originated from tropical and sub-tropical parts of America. Being a strong flier, climatic adaptation and large host range makes it a serious threat to food security. It is responsible for high economic losses in many cash crops, vegetables and cereals. The overreliance and overuse of pesticides for the management of FAW posed many problems including insecticide resistance, resurgence of insect pests, biotype development and environmental hazards. To combat these problems, the most important alternative is the use of green synthesis nanoparticles and biocontrol agents which have been proven as eco-friendly technology for pest control. The current study was, therefore, planned to evaluate the toxicity of different plant based synthetic nanoparticles and biocontrol agent (Trichogramma spp.) against fall armyworm. Silver nanoparticles of neem resulted in the highest (83%) and the lowest (40%) mortality of 2nd instar larvae of FAW. However, the highest mortality due to silver nanoparticles of tobacco, onion, mint, ginger and datura was observed as 86%, 63%, 76%, 63% and 73% while the lowest mortality was 30%, 33%, 30%, 23% and 16% respectively. In view of the current findings nanoparticles of datura and neem could be recommended as potential bio-based chemicals for the control of S. frugiperda.

Laboratory bioassay of fall armyworm (Spodoptera frugiperda) larva using various insecticides

Fall armyworm (FAW), Spodoptera frugiperda J.E. Smith, is a polyphagous invasive pest that seriously affects the maize crop. Various insecticides such as Spinosad, Chlorantraniliprole, Imidacloprid, Emamectin benzoate, Spinetoram and Neem-based insecticides are recommended to control this pest. However, their efficacy is not well studied in Nepal. Hence, a study was performed to evaluate the efficacy of the above-mentioned insecticides for FAW management in laboratory experiments. Seven different treatments (six insecticides such as Spinosad 45% SC, Chlorantraniliprole 18.5% SC, Imidacloprid 17.8% SL, Emamectin benzoate 5% SC, Spinetoram 11.7% SC, Neem-based pesticide (Azadirachtin 1500 ppm) and control (water spray) were evaluated in three replicated CRD design. Spinosad and Spinetoram were found effective for the FAW mortality in which > 50% mortality of the larva was obtained in twelve hours and > 90 % mortality in twenty-four hours. Likewise, Emamectin benzoate and Chlorantraniliprole also caused > 90% mortality within twenty-four hours. Azadirachtin and Imidacloprid were not as effective as other pesticides that caused only 17% larval mortality in the first twelve hours and 68% mortality in sixty hours. Similarly, Imidacloprid caused 8% larval mortality in twelve hours and 59% mortality in sixty hours. There was no mortality in water spray (control). This information gives an idea of all pesticides are not equally effective and efficient. Such information’s are important to the farmers to select the right insecticides for the control of FAW in maize crops.

Host plant preference by the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Noctuidae: Lepidoptera) on the range of potential host plant species

Maize is the most important cereal crop after rice and wheat in Asia. Nowadays, maize production is threatened by one invasive pest, the fall armyworm (Spodoptera frugiperda) particularly in Africa and Asia, and threatens millions of poor people. Fall armyworm feeds a wide range of crops and non-crops including weeds, with over 353 plant species. But most frequently consumed crops are field corn, sweet corn, wheat, sorghum, sugarcane, Bermuda grass etc. Fall armyworm has six larval stages, the first three stages are less voracious compared to the latter stages. Larvae are very numerous and disperse in large numbers and behave like ‘armyworm’. Insecticides are considered an important tool of FAW management as well as other lepidopteran maize pests. However, these practices are not sustainable and are linked to the environment, biodiversity and farmers' health. Alternative management strategies should be developed by understanding pest biology and ecology. Hence, a series of laboratory choice and paired-choice tests were conducted at Agriculture and Forestry University in May 2021 to evaluate the host plant preference by the fall armyworm. Potential host plants were Zea mays (maize cultivars - Rampur composite, Arun-2 and Rampur hybrid-10), Pennisetum purpureus (Napier), Oryza sativa (rice), Sorghum bicolor (Sorghum), Fagopyrum esculentum (Buckwheat), Vigna unguiculata (Cowpea) and Glycine max (Soybean). In choice tests, FAW preference was ranked as Rampur Composite > Sorghum > Rampur hybrid-10 > Arun-2 > Napier > Rice > Buckwheat > Cowpea > Soybean. Rampur composite and sorghum were the most preferred host plants, Rampur hybrid, Arun-2 and Napier were the medium preferred, rice was categorized as the low preferred and other host plants such as buckwheat, cowpea and soybean were the least preferred host plant of fall armyworm. In paired-choice tests, Rampur composite was more preferred than sorghum, but not significantly so. These research findings are useful to utilize in habitat manipulation strategies for fall armyworm management. Most preferred plant species can be deployed as trap crops and least preferred host plants can be used as repellent or push crops in a push-pull strategy. Such host plants in-and-around the main field can reduce the fall armyworm damage and reduce pesticide amount in main crops.

Reliability of Pheromone Trap Catches and Maize Plant Damage as Criteria for Timing Fall Armyworm Control Interventions in Humid Forest Agroecology of Central Africa.

Control of fall armyworm (FAW) Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) since its invasion of Africa still depends on pesticides. Early detection of adults is considered the key to the success of larvae control in the crop field. However, FAW control thresholds based on current monitoring techniques are not well established in Africa. We investigated the efficacy of moth capture frequencies and FAW incidence levels as decision tools for FAW management. Experiments were conducted over two maize cropping seasons during which FAW incidence, severity, and larvae count were recorded during destructive sampling after the application of a homologated insecticide. During the first season, the FAW incidence ranged from 37.5 ± 5.6% in the 25% incidence threshold treatment to 48.1 ± 8.1% in the control. During the second season, the incidence was significantly lower in the 25% incidence threshold treatment (55.8 ± 5.7%) compared with the control (75.7 ± 3.0%). Over the two seasons, no significant difference in FAW damage severity was recorded between the treatments and control. The highest number of larvae per plant (4.0 ± 0.6) was observed in the 10% incidence threshold treatment. Insecticide application did not consistently contribute to reducing FAW incidence and observed plant damage did not translate into yield loss. FAW control needs further investigation to establish a threshold above which damage translates into yield loss, thus necessitating control intervention.

Performance of the domestic Bt corn event expressing pyramided Cry1Ab and Vip3Aa19 against the invasive Spodoptera frugiperda (J. E. Smith) in China.

The invasive fall armyworm, Spodoptera frugiperda (J.E. Smith), has caused serious corn yield losses and increased the frequency of insecticide spraying on corn in Africa and Asia. Drawing lessons from the use of Bt corn to manage fall armyworm in the Americas, China released a certificate for the genetically modified corn event DBN3601T pyramidally expressing Cry1Ab and Vip3Aa19 for industrialization in 2021. Performance of the DBN3601T event against invasive fall armyworm in China was evaluated by plant tissue-based bioassays and field trials during 2019-2021. In the bioassays, tissues and organs of DBN3601T corn differed significantly in lethality to fall armyworm neonates in the order: leaf > husk > tassel and kernel > silk. In field trials, compared with non-Bt corn, DBN3601T corn greatly suppressed fall armyworm populations and damage; larval density, damage incidence, and leaf damage scores for DBN3601T corn were significantly lower than for non-Bt corn at different vegetative stages, and efficacy against larval populations during the 3 years ranged from 95.24% to 98.30%. A laboratory bioassay and 3-year field trials confirmed that DBN3601T corn greatly suppressed fall armyworm populations and has high potential as a control of this invasive pest, making it a key tactic for integrated management of fall armyworm in China. © 2022 Society of Chemical Industry.

Maize farmers’ knowledge and management of fall armyworm (Spodoptera frupigerda) in southwest Nigeria

This study investigated maize farmers’ knowledge, control methods, and perception of the invasive and highly destructive insect pest, fall armyworm (Spodoptera frugiperda) in southwest Nigeria. A four-stage sampling procedure was employed in selecting 195 maize farmers in the study area. Data were obtained with the aid of structured questionnaire and analysed using percentages, means, standard deviations, and chi-square test. The majority (88.7%) of respondents observed fall armyworm attack within two months after sowing, only 30.8% of them reported total damage to maize plants by fall armyworm. Most (75.9%) of the respondents could describe the destructive larval stage of fall armyworm, 58.5% of respondents exclusively applied synthetic insecticides for fall armyworm management. The most common insecticides used by respondents were organophosphates (37.2%), pyrethroids (29.0%) and avermectins (18.2%). Perception of fall armyworm damage as a serious and worrisome problem was very high (4.82) amongst maize farmers. Strong and significant association (χ2 = 41.3) was found between farmers’ agroecological zones and the severity of fall armyworm damage reported. Integrated pest management approach is a sustainable alternative to the sole use of insecticides and should be promoted. Information provided in the study will enhance decision-making for fall armyworm management interventions in southwest Nigeria.

Laboratory and Field Performance of Metarhizium anisopliae Isolate ICIPE 41 for Sustainable Control of the Invasive Fall Armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae)

To overcome the negative impacts of invasive fall armyworm (FAW), this study assessed the laboratory and field efficacy of aqueous and oil-based formulations of Metarhizium anisopliae ICIPE 41 as an alternative source for FAW management. Three oil formulations, including canola, corn and olive oils and an aqueous formulation of ICIPE 41, were assessed against the second-instar larvae of FAW in the laboratory. Field experiments were also conducted at Mbita and Migori, Kenya, using the formulation that performed best in the lab, with four treatments: (a) A corn oil formulation of ICIPE 41; (b) Mazao Achieve® biopesticide, with the M. anisopliae ICIPE 78 strain as the active ingredient; (c) spinetoram-based synthetic pesticide; (d) a control (water + corn oil). FAW incidence, infestation, larval mortality and the effects on parasitoids and yield were evaluated. The laboratory results showed no significant differences in the efficacies among the oil-based formulations, with mortality rates of >70% and an LT50 of ~2 days compared to 15.15% in the controls with an LT50 of 8.11days. Under the field conditions, no significant differences in the FAW infestation were observed between ICIPE 41 and Mazao Achieve®, compared to the control treatments in both agro-ecological zones. From the field-collected samples, both fugal-based biopesticides exhibited high mortality and mycosis rates, with no negative impacts on Cotesia icipe compared to the spinetoram pesticide. There were significant differences in the total grain yields among the treatments in Mbita and Migori. Therefore, ICIPE 41 formulated with corn oil could be used for sustainable FAW management in maize cropping systems.

Sustainable Management of Invasive Fall Armyworm, Spodoptera frugiperda

The fall armyworm of maize, Spodoptera frugiperda (J. E. Smith) (Lepidoptera; Noctuidae) is capable of causing a 100% yield loss due to its unforeseen occurrence from the seedling to the cob formation stage. To manage this serious pest, maize growers are tending to apply a high dosage of pesticides. This indiscriminate usage of pesticides has resulted in an unacceptable amount of insect resurgence in maize, harming maize production and consumption. In this review, we prepared a list of practical pest management options, including host plant resistance, agronomical, cultural, biological, botanical, chemical, and biotechnology approaches. It was found that cultivation of tolerant genotypes, adjusting sowing windows, and practicing specific intercultural and cropping systems measures in addition to chemical and non-chemical pest management strategies showed encouraging results for sustainable management of fall armyworm, which could protect the crop. This review highlights novel and successful management options advocated in various parts of the world. Recommendations documented in this paper would certainly pave the way for successful management of fall armyworm in maize and other concerned crops.

RNA interference (RNAi) applications to the management of fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae): Its current trends and future prospects.

The fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) is among the invasive insect pests that damages maize and sorghum, the high-priority crops in newly colonized agro-ecologies, including African contexts. Owing to the increasing infestation of the pest and the limitations of current conventional methods for its management, there is a call for discovering advanced pest management approaches. RNA interference (RNAi) is an emerging molecular tool showing flexible potential for the management of S. frugiperda. We conducted a search of the recent application of RNAi literature using Google Scholar and Mendeley to find advanced papers on S. frugiperda management using RNAi molecular tools that led to growth inhibition, developmental aberrations, reduced fecundity, and mortality, mainly by disruption of normal biological processes of the pest. Although efforts have been made to accelerate the utility of RNAi, many factors limit the efficiency of RNAi to achieve successful control over S. frugiperda. Owing to RNAi’s potential bioactivity and economic and ecological acceptability, continued research efforts should focus on improving its broad applicability, including field conditions. Screening and identification of key target genes should be a priority task to achieve effective and sustainable management of this insect via RNAi. In addition, a clear understanding of the present status of RNAi utilization in S. frugiperda management is of paramount importance to improve its efficiency. Therefore, in this review, we highlight the biology of S. frugiperda and the RNAi mechanism as a foundation for the molecular management of the pest. Then, we discuss the current knowledge of the RNAi approach in S. frugiperda management and the factors affecting the efficiency of RNAi application. Finally, the prospects for RNAi-based insect pest management are highlighted for future research to achieve effective management of S. frugiperda.

POPULATION DYNAMICS OF Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) IN PERAMBALUR DISTRICT OF TAMIL NADU

The Fall Armyworm (FAW), Spodoptera frugiperda (J.E. Smith), a migratory polyphagous pest with high feeding preference to maize, is native to American continent but detected in African continent in the year 2016 and reached the Indian sub-continent by 2018. Now the pest has been spread over the maize growing states in India and causing drastic economic loss. Studies on population dynamics of Spodoptera frugiperda was carried out in all the four blocks of Perambalur district of Tamil Nadu by conducting the season long survey with the aim to correlate the occurrence and weather variables. The number of egg masses and larval population were counted and percent infestation was worked out. Among the four blocks, Veppur block showed the heavy infestation of 85%. Thus, the climatologic conditions prevailing in the cropping season decides the fluctuation and abundance of FAW. So, abiotic factors must be taken into consideration in the IPM model for the management of FAW.

A Take-Home Message "Fall Armyworm Management in Asia and the Pacific Region"

A Take-Home Message "Fall Armyworm Management in Asia and the Pacific Region"- Y.D. GC

Gut Endosymbiont Disruption through Antibiotics Influences the Metabolic Homeostasis in Spodoptera frugiperda (Lepidoptera: Noctuidae) Larvae

Fall armyworm as a polyphagous voracious feeder reported causing yield losses in most agriculturally important crops. As this insect had developed resistance against most of the insecticides, there is a need for an alternate approach to management. Gut endosymbiotic bacteria play a significant role in host feeding, digestion, and defense response throughout the life stages of insects. In the present study, we have isolated and identified the gut endosymbiotic bacteria of fall armyworm and the larvae were treated with antibiotics. The results showed that the maximum bacterial population was observed in the fourth instar of field-caught larvae and the least population was observed in the fourth instar artificially reared population. Based on the biochemical results the isolated gut endosymbiotic bacteria mainly comprised of Bacillus sp, Enterococcus sp., and Enterobacter sp. Based on the susceptibility of gut bacteria to different antibiotics, 6 antibiotic treatments with one insecticide treatment were administered to an artificial diet reared with third instar larvae and their dietary indices were evaluated. Among the antibiotic treatment, there was a reduction in the dietary indices in the larvae treated with Ciprofloxacin CIP5 (45.33%) and Cefotaxime CTX30 (41.73%) and an increase in dietary indices in the larvae treated with Nalidixin NA30 (31.58%), Doxycycline DO30 (8.82%), Vancomycin VA30 (22.05). Elimination of gut bacteria with a suitable antibiotic will affect the insect’s feeding and dietary indices subsequently decreasing the relative growth rate and insect’s physiology. Hence, gut bacteria-based green control measures might be used as an alternative approach for insecticides for the effective management of fall armyworm.

Sustainable management of fall armyworm in smallholder farming: The role of a multi‐channel information campaign in Rwanda

AbstractIn recent years, fall armyworm (FAW), Spodoptera frugiperda, has emerged as one of the most serious invasive species in many countries across Africa, Asia and Oceania. The pest is causing extensive damage to maize production and the intensification of pesticide use. In this paper, we examined the effectiveness of three mass‐extension channels (plant health rallies, radio drama and SMS) in enhancing farmers' knowledge and management of FAW and in increasing maize productivity. Applying matching techniques to data from 720 smallholder farmers and 1077 maize plots in Eastern Rwanda, we found that exposure to the information channels is significantly associated with increased knowledge outcomes, including knowledge of the correct identification of FAW and the use of cultural practices as the first resort to pest management. Moreover, the information channels showed positive effects on the adoption of environmentally friendly management practices. Generally, the treatment effects are larger for households exposed to multiple (especially all) channels, indicating complementary effects of the channels. We also found suggestive evidence that the information channels are associated with maize yield increases ranging from 10% to 34%, depending on the channel. Overall, the results imply that multi‐channel information campaigns can be effective in enhancing farmers' knowledge on how to identify and sustainably manage the FAW pest. Our findings also suggest that while there is a growing popularity in the use of digital extension approaches to deliver timely information to farmers in a cost‐effective manner, much greater gains can be achieved if they are combined with other low‐cost face‐to‐face extension methods, such as plant health rallies.

Leaf Damage Based Phenotyping Technique and Its Validation Against Fall Armyworm, Spodoptera frugiperda (J. E. Smith), in Maize.

Globally, maize is an important cereal food crop with the highest production and productivity. Among the biotic constraints that limit the productivity of maize, the recent invasion of fall armyworm (FAW) in India is a concern. The first line of strategy available for FAW management is to evaluate and exploit resistant genotypes for inclusion in an IPM schedule. Screening for resistant maize genotypes against FAW is in its infancy in India, considering its recent occurrence in the country. The present work attempts to optimize screening techniques suited to Indian conditions, which involve the description of leaf damage rating (LDR) by comparing injury levels among maize genotypes and to validate the result obtained from the optimized screening technique by identification of lines potentially resistant to FAW under artificial infestation. Exposure to 20 neonate FAW larvae at the V5 phenological stage coupled with the adoption of LDR on a 1–9 scale aided in preliminary characterize maize genotypes as potentially resistant, moderately resistant, and susceptible. The LDR varies with genotype, neonate counts, and days after infestation. The genotypes, viz., DMRE 63, DML-163-1, CML 71, CML 141, CML 337, CML 346, and wild ancestor Zea mays ssp. parviglumis recorded lower LDR ratings against FAW and can be exploited for resistance breeding in maize.

Management of fall army worm (FAW) in maize

Management of fall army worm (FAW) in maize

Fungal and viral entomopathogens as a combined strategy for the biological control of fall armyworm larvae in maize

BackgroundThe fall armyworm Spodoptera frugiperda is one of the major pests in maize crops, causing important production losses. The pest has rapidly spread worldwide, generating an urgent need to develop efficient and sustainable strategies for its control. In this work, the potential of integrating nucleopolyhedrovirus- (NPV) and the fungus Metarhizium rileyi to control S. frugiperda larvae was evaluated under laboratory, greenhouse, and field conditions.MethodsThe mortality of S. frugiperda larvae was evaluated after the application of NPV and M. rileyi alone or in combination using three concentrations (high, medium and low) under laboratory conditions. Then, two greenhouse trials using maize plants were carried out to evaluate the effect of individual or combined applications of NPV and M. rileyi on S. frugiperda mortality (first trial) and fresh damage (second trial). Finally, a trial under field conditions was conducted to evaluate the performance of the treatment selected in the greenhouse assay.ResultsThe combined use of NPV: M. rileyi applied simultaneously showed an additive effect in laboratory, causing higher larval mortality than the biocontrol agents used separately. This effect was evident in the mixtures using the concentration levels high:medium, medium:medium, and medium:high. Under greenhouse conditions, the use of a 50:50 ratio of the two entomopathogens also caused higher larval mortality and a significantly reduced insect damage to plants. Finally, under field conditions, the individual or sequential application of NPV and M. rileyi using 100% of their recommended doses, and the simultaneous application of both entomopathogens at 50% of their recommended doses, significantly reduced the recent foliar damage to levels under the threshold for economic losses (30% fresh damage) while the damage reached 43% when control measures were not used.ConclusionThe combined application of NPV and M. rileyi (two biocontrol agents with different mode of action) demonstrated an additive effect that allows to reduce to half their recommended application doses. In this context, the integration of both entomopathogens is a promising strategy to manage S. frugiperda, contributing to improve the economic feasibility of biological control tools for the sustainable fall armyworm management.

Assessing the Single and Combined Toxicity of Chlorantraniliprole with Bacillus thuringiensis against Maize Fall Armyworm Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) under Laboratory Conditions

Use of synthetic insecticides for the management of fall armyworm (FAW) Spodoptera frugiperda (J. E. Smith) for a longer period will led to development of insecticide resistance. Identification of an eco-friendly synergistic agent to enhance the toxicity potential and reduced pesticide use as well become mandatory in due process. Hence the present study was formulated to find the single and combined toxicity of chlorantraniliprole and Bacillus thuringiensis (Bt) against the 2nd and 3rd larval instars of S. frugiperda. Single toxicity of chlorantraniliprole against 2nd and 3rd larval instars were 0.87 and 1.52 ppm (LC25); 4.08 and 6.50 ppm (LC50), respectively. With respect to Bt, single toxicity against 2nd and 3rd larval instars were 474.39 and 693.48 ppm (LC25); 1008.62 and 1228.62 ppm (LC50), respectively. Combination effect of chlorantraniliprole with Bt revealed that 2nd instar of FAW showed supplemental synergism at LC50 of chlorantraniliprole + LC25 of Bt. In the case of LC50 of chlorantraniliprole + LC50 of Bt, LC25 of chlorantraniliprole + LC50 of Bt and LC25 of chlorantraniliprole + LC50 of Bt combinations, they showed sub additive synergism. In 3rd instar larvae, the combined toxicity results were similar for all the combinations of chlorantraniliprole + Bt except LC25 of chlorantraniliprole + LC50 of Bt where it showed an antagonistic synergism. Activity of Carboxyl Esterase (CarE), Mixed Function Oxidase (MFO) and Glutathione-S-Transferase (GST) were found to be lesser in chlorantraniliprole LC50 + Bt LC25 combinations than single toxicity treatments. Therefore, combined use of chlorantraniliprole with Bt at LC50 of chlorantraniliprole + LC25 of Bt had supplemental synergism on fall armyworm under laboratory condition.

Biosilica Fertilizer Reduces Fall Armyworm Damage

The presence of fall armyworm (FAW), Spodoptera frugiperda J.E. Smith, in Indonesian corn plantations caused the farmers' dependence on chemical insecticides increased. Since chemical pesticides have several side effects, it is necessary to develop another alternative to FAW management. This study aimed to investigate the efficacy of biosilica fertilizer against FAW incidence and its effect on maize production. A factorial experiment was arranged in two factors, the first factor was biosilica doses with varied doses of 1, 2, and 3 l/ha; the second factor was the number of applications at 1, 2, and 3 times. The results demonstrated that the application of biosilica fertilizer 2 - 3 l/ha as foliar spray three times starting from 10 days after growing reduced the fall armyworm infestation significantly as compared to control treatment. No significant differences were observed in the vegetative characteristics of corn plants, i.e height and the number of leaves, in response to doses and application number of biosilica. Application of biosilica 2 - 3 l/ha improved the yield attributing characters of the corn plant and increased the production as compared to other treatments including control treatment. We conclude that biosilica fertilizer can be used as an alternative for FAW management.

Bio-efficacy of insecticides against fall armyworm

A field experiment was conducted in a randomized block design to find out the effective management of fall armyworm, Spodoptera frugiperda (J S Smith) in maize (Zea mays L.) through different insecticides and bio-pesticides during kharif 2019 and 2020 at Agronomy farm, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur, Rajasthan. The three sprays of chlorantraniliprole 18.5 SC were found most effective treatment against S. frugiperda and gave the better results with maximum reduction of larval population, lowest plant damage (%), lowest leaf damage (%), lowest cob damage (%) and highest grain yield. It is followed by emamectin benzoate 5 SG and found at par at 5th day after each spray. The next effective treatments were spinosad 45 SC, thiodicarb 75 WP, Beauveria bassiana, Metarhizium anisopliae and azadirachtin 10000 ppm. The maximum Incremental Benefit Cost Ratio was obtained from the three sprays of emamectin benzoate 5 SG.