Armyworm Attack Research Articles

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.

Influence of the Season on Armyworm (Spodoptera frugiperda J.E. Smith) Attacks on Some Bio-fortified maize (Zea mays L.) Varieties Introduced in Kisangani Eco-region (Democratic Republic of the Congo)

The present study was conducted in the Kisangani region of the northeastern Democratic Republic of Congo in 2018-2019. The objective was to evaluate the influence of the seasons in the face of armyworm attacks on the behavior of three new biofortified maize varieties being introduced in the Tshopo Province. These trials were conducted using a split plot design with three replications and the results were analyzed using R Studio version 3.6 statistical software. The results at (p<0.05) show that all three varieties were attacked by armyworms. The overall average incidence was significantly similar to that of the control. During two cropping seasons, the maize varieties tested showed variable armyworm attack rates: Yellow Plata (14.16%) SAM4 VITA/A (18.05%) SAM4 VITA/B (16.44%) and PVA SYN- 18 F2'' (14.66%). As for the variation of attack between seasons, the results of the statistical analysis showed that season B had a higher attack rate (25.54%) than season A (6.11%).

Effects of Fertilization, Variety and Season on Fall Armyworm Attack on Bio-fortified Maize Production in the Kisangani Eco-region (Democratic Republic of the Congo)

Faced with soil impoverishment and irregular rainfall caused by climate change, a study has been initiated on the cultivation of bio-fortified maize in Kisangani in the Northeast of the Democratic Republic of the Congo. The study aimed at evaluating fertilization effects, new bio-fortified maize varieties and the season (Zea mays L) on production in the face of armyworm infestation. The split-plot experimental set-up was used, the first factor has been the variety and the second the fertilizers. The results have highlighted that the application of fertilizers at the sowing time does not significantly influence any production parameter. However, experimented maize varieties have differently behaved depending on seasons when the armyworm infestation.

The rice wound-inducible transcription factor RERJ1 sharing same signal transduction pathway with OsMYC2 is necessary for defense response to herbivory and bacterial blight.

This study describes biological functions of the bHLH transcription factor RERJ1 involved in the jasmonate response and the related defense-associated metabolic pathways in rice, with particular focus on deciphering the regulatory mechanisms underlying stress-induced volatile emission and herbivory resistance. RERJ1 is rapidly and drastically induced by wounding and jasmonate treatment but its biological function remains unknown as yet. Here we provide evidence of the biological function of RERJ1 in plant defense, specifically in response to herbivory and pathogen attack, and offer insights into the RERJ1-mediated regulation of metabolic pathways of specialized defense compounds, such as monoterpene linalool, in possible collaboration with OsMYC2-a well-known master regulator in jasmonate signaling. In rice (Oryza sativa L.), the basic helix-loop-helix (bHLH) family transcription factor RERJ1 is induced under environmental stresses, such as wounding and drought, which are closely linked to jasmonate (JA) accumulation. Here, we investigated the biological function of RERJ1 in response to biotic stresses, such as herbivory and pathogen infection, using an RERJ1-defective mutant. Transcriptome analysis of the rerj1-Tos17 mutant revealed that RERJ1 regulated the expression of a typical family of conserved JA-responsive genes (e.g., terpene synthases, proteinase inhibitors, and jasmonate ZIM domain proteins). Upon exposure to armyworm attack, the rerj1-Tos17 mutant exhibited more severe damage than the wildtype, and significant weight gain of the larvae fed on the mutant was observed. Upon Xanthomonas oryzae infection, the rerj1-Tos17 mutant developed more severe symptoms than the wildtype. Among RERJ1-regulated terpene synthases, linalool synthase expression was markedly disrupted and linalool emission after wounding was significantly decreased in the rerj1-Tos17 mutant. RERJ1 appears to interact with OsMYC2-a master regulator of JA signaling-and many OsJAZ proteins, although no obvious epistatic interaction was detected between them at the transcriptional level. These results indicate that RERJ1 is involved in the transcriptional induction of JA-mediated stress-responsive genes via physical association with OsMYC2 and mediates defense against herbivory and bacterial infection through JA signaling.

APLIKASI INSEKTISIDA NABATI BERBAHAN TANAMAN RAWA UNTUK MENGENDALIKAN HAMA KEDELAI ULAT GRAYAK (Spodoptera litura) DI LAHAN RAWA PASANG SURUT

One type of pest that often attacks soybean plant leaves in tidal swamplands is the armyworm pest. The intensity of leaf damage due to armyworm attack in tidal swamps ranges from 30-95%, and can even lead to crop failure. In controlling pests in soybean plants in general, always rely on chemical insecticides. The use of these chemical insecticides has a negative impact on the environment. To overcome this, the control is directed towards environmentally friendly pest control by utilizing swamp plants as a botanical insecticide. The study used a randomized block design (RBD) with 3 treatments of swamp plant extracts (galam, kirinyuh, kepayang) and 3 controls, namely without control, botanical insecticide made from neem, chemical insecticide with the active ingredient kloraniliprol. The aim of this study was to obtain a swamp plant extract that could be used in controlling armyworm pests (Spodoptera litura). The results showed that the three types of swamp plants could be used as botanical insecticides in controlling armyworm pests, and has an effectiveness value above 70%. The highest effectiveness of botanical insecticides was obtained at the age of 75 DAP, namely Galam (78.29%), Kirinyuh (78.86%) and Kepayang (78.85%).

Impact of climate change to fall armyworm attack on maize in Karo District, North Sumatera

Climate change affects agriculture in some ways including changes in average temperatures, rainfall, and climate extremes with an important impact on pests and diseases. Several types of pests that arise as a result of the climate change and attacked corn plant is Spodoptera frungiperda. This study aims to analyze the relationship between various climate factors with the area affected by Spodoptera frugiperda in the Karo District, North Sumatera. The area used in this study is Karo District, North Sumatera because this is the area with the widest area affected by FAW on maize cropping. The highest area affected on maize in Karo District occurred in April of 1.533 ha. The analysis used in this research is multiple linear regression. Climate factor data are used as independent variables and area affected data as dependent variables. Based on data analysis with multiple linear regression owned by all factors influence on the area affected with a coefficient of determination (R2) of 0.882. Climate factors that have a significant influence on the area affected are rainfall.

RNA-Seq identification of candidate defense genes by analyzing Mythimna separata feeding-damage induced systemic resistance in balsas teosinte.

Armyworm (Mythimna separata) is a destructive herbivore for maize. Balsas teosinte (Zea mays ssp. parviglumis), the direct wild ancestor of cultivated maize, has shown great potential to defend against herbivory. Here, based on armyworm bioassay, we compared responses of teosinte and B73 maize inbred during armyworm attack in their transcriptome profiles to elucidate the gene expression changes involved in teosinte responses to armyworm attack. The goal of this study was to identify novel resistance alleles that could serve as valuable resources for modern maize breeding. Our bioassay revealed that armyworm larvae grew less on teosinte than on maize. A follow-up transcriptomic comparison showed more down-regulated genes in maize B73 and similar numbers of up-regulated genes in both genotypes under armyworm attack. The up-regulated genes in teosinte were markedly enriched in MAPK cascade-mediated signaling pathway and phytohormone pathway. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that phytohormones jasmonic acid, ethylene, salicylic acid and abscisic acid (ABA) were actively involved in armyworm resistance of teosinte plants, and so were transcription factors such as MYBs, WRKYs and TIFYs. Interestingly, teosinte also showed high regulation in three ABA receptor PYLs. Based on differential expression analysis, we identified 30 candidate defense-related genes in teosinte, which belong to 11 gene families and the majority of the genes were up-regulated, while some of them were nonresponsive in maize. This study demonstrates that teosinte showed more vigorous defense response than maize toward armyworm attack and might be a beneficial genetic resource to improve pest resistance in cultivated maize. © 2019 Society of Chemical Industry.

Formulation of insecticide profenofos using Surfactant Diethanolamide (DEA) based on palm olein

Soybean is one of the major food commodities in Indonesia that the consumption is increasing each year, but this is not in line with the domestic soybean production capacity. One cause of the low production capacity is the armyworm attact. Generally, the armyworm attack controled by spread insecticide profenofos. Profenofos need to be dissolved, but profenofos couldn’t dissolved in water. So that, it need the right formulation between the solvent and other ingredients which can supprotprofenofos performance. One of that ingredient is surfactant. This research used surfactant diethanolamide (DEA) based on palm olein. DEAfunction in insecticide formulation are as homogenizer, dispersant, sticker and spreader agent.The aims of this research are to obtain the best emultion insecticide product based on profenofos as the active ingredients and DEA as the surfactant, moreover it also to obtain information of the physico-chemical properties. The formulation test performed with compeletely randomized design (CRD) with two factors, first factor is DEA concentrationand the second factor is profenofos concentration. Data of physico-chemical properties test was analyzed by analysis of variance (ANOVA) and significant result tested by Duncant Multiple Range Test (DMRT).The result showed that, surfactant DEA could make good emultion between profenofos and sodium ethoxide as the solvent. The best treatment which obtain from formulation stage is concentrate with DEA 10% and profenofos 40%. Physico-chemical properties test result showed that droplet size is 1,76–2,07 µm, contact angle 11,575–24,218°, density 0,996–0,998 g/cm3, surface tension 16,56–40,72 dyne/cm, viscosity 1,032–1,078 Cp and pH 6,87–8,22.

Air-Assistance in Spray Booms which have Different Spray Volumes and Nozzle Types for Chemically Controlling Spodoptera Frugiperda on Corn

The study aimed to evaluate the performance of air assistance in spray booms using different types of nozzles and spray volumes. We took into account spray deposits, fall armyworm control and crop corn performance in a narrow row cropping system. The experiment was carried out at the experimental area of Sao Paulo State University, Botucatu/SP, Brazil, during the 2008/2009 ag- ricultural season, in randomized blocks with a factorial scheme (2x2+1) and four replications. Two spray nozzles (flat fan nozzle and hollow cone nozzle) were tested, combined with two air assistance levels in the spray boom (with and without air assistance) and a treatment control. In the experimental spraying, Spinosad insecticide was sprayed in amounts of 48 g active substance (a.s.)/ha. The air assistance in the spray boom increased the spray deposits in the V 4 growth stage of the corn plants. Moreover, the application of this technology showed higher efficiency on fall armyworm control, reaching a 100% level 15 days after spraying, in the V 10 growth stage of the plants. The hollow cone nozzle increased the spray deposit level on the corn plants compared with the flat fan nozzle, at growth stage V 4 . However, the flat fan nozzle, combined with air assistance technology, was more effective for controlling fall army- worm in the same growth stage (V 4 ), although the hollow cone nozzle increased the deposit levels on the plants. All the technologies tested in the study promoted a reduction of plant damage from fall armyworm attack. Corn productivity is directly related to the control efficiency of fall armyworm.

A novel wheat gene encoding a putative chitin‐binding lectin is associated with resistance against Hessian fly

SUMMARY The gene-for-gene interaction triggering resistance of wheat against first-instar Hessian fly larvae utilizes specialized defence response genes not previously identified in other interactions with pests or pathogens. We characterized the expression of Hfr-3, a novel gene encoding a lectin-like protein with 68-70% identity to the wheat germ agglutinins. Within each of the four predicted chitin-binding hevein domains, the HFR-3 translated protein sequence contained five conserved saccharide-binding amino acids. Quantification of Hfr-3 mRNA levels confirmed a rapid response and gradual increase, up to 3000-fold above the uninfested control in the incompatible interaction 3 days after egg hatch. Hfr-3 mRNA abundance was influenced by the number of larvae per plant, suggesting that resistance is localized rather than systemic. In addition, Hfr-3 was responsive to another sucking insect, the bird cherry-oat aphid, but not to fall armyworm attack, wounding or exogenous application of methyl jasmonate, salicylic acid or abscisic acid. Western blot analysis demonstrated that HFR-3 protein increased in parallel to mRNA levels in crown tissues during incompatible interactions. HFR-3 protein was detected in both virulent and avirulent larvae, indicating ingestion. Anti-nutritional proteins, such as lectins, may be responsible for the apparent starvation of avirulent first-instar Hessian fly larvae during the initial few days of incompatible interactions with resistant wheat plants.

Migration and meteorology: flight behaviour and the atmospheric environment of locusts and other migrant pests

Part 1 The desert locust - prototype migrant: locust control and migration - the background locust migration - facts and mechanisms biology and behaviour of the desert locust in relation to migration displacements of discrete locust populations locust migration, winds and weather on the intercontinental scale - the desert locust and synoptic meteorology locust numbers - the evidence and the problem of control the assessment of locust numbers and of control operations locusts at a low ebb - continuity of recession populations swarming and solitary phases outline of a recession - treatment of data - findings experience of recession forecasting current status of the Phase Theory. Part 2 Flight and migration in other major pests armyworms - larvae of formidably migrant moths sample of the armyworm problem - Sierra Leone 1979 trans-equatorial sequences of armyworm attack analogies with locusts establishing the timing and spacing of infestations in relation to the distribution of the moths forecasting in East Africa infestations - incursions of westerly winds and other early evidence moth flight - from circumstantial evidence to radar observations and marking/capture possible antecedents of armyworm attacks in West Africa - squall-line studies for WHO/ONCHO and other clues armyworm control - current approaches and some future possibilities spruce budworm - major forest problem of North America the background - problems of the economy and the environment budworm moth flight - observations by radar and aircraft. Part 3 Management of migrant pests - prospects and options, some suggestions: problems of the desert locust and other locusts of Africa African armyworm - prospects and options spruce budworm - prospects and options major migrant pests in China - possible new options for monitoring and control migrant pests and nuclear winter. Part 4 Ecology and evolution of insect flight and migration - some implications from findings on migrant pests survival value of systems of downwind redistribution migration - a single strategy implemented by a range of alternative tactics evolution of insect flight migration without navigation navigation in static populations - the honey-bee. Appendices Further notes on applications of meteorology in investigations of airbourne migration: 1 - some points of meteorological observation and analysis, surface and upper air 2 - problems of observation and interpretation of field/phenomena - some analogies from meteorological procedures 3 - hour-to-hour movements of individual swarms in relation to wind.

The Relation Between Simulated Armyworm Damage and Crop-Loss in Maize and Sorghum

An account is given of experiments with maize and sorghum, growing in Kenya and Uganda, respectively, in which varying amounts of defoliation were related to resulting crop loss and to other effects upon the growth of the plants. The defoliation was intended to simulate damage by Spodoptera exempta Wlk.; the objective was to obtain data from which the extent of crop loss to be expected from varying intensities of armyworm attack could be predicted and thus the advisability assessed of carrying out control with economic advantage.The experiments showed that, especially under favourable environmental conditions, regeneration after defoliation of both maize and sorghum in the earliest stages of growth treated can be virtually complete. In general, it is concluded that, when defoliation affects leaves only and takes place very early in the growth of the plant (up to the five-leaf stage in maize) crop loss is negligible; it becomes more important the later the stage of growth at which it occurs, and when the stem is also damaged crop loss is always severe; the loss is complete when damage occurs at later growth stages. In sorghum, owing to tillering, the effects of defoliating the primary stem are less important; destruction of the primary stem itself results in crop loss that is severe, although less so than in the corresponding maize treatment, and a crop, although greatly reduced, is produced even when it is destroyed at the latest stage of treatment. The curious behaviour of the primary meristem in maize and its effect on the results of destruction of the stem at different stages are described.Differences between defoliation as effected experimentally and as brought about by armyworm attack are discussed. Sustained attack and destruction of foliage by armyworms may ultimately render the damage more serious. Certain side-effects of armyworm attack, such as the fertiliser-effect of their droppings and their possible poisoning action when ingested by cattle in pastures, are also discussed