Percentage Of Pupae Research Articles

Influences of Different Host Plants on Biological and Food Utilization of the Cotton Leafworm, Spodoptera littoralis

The effects of four host plants, broad bean, cabbage, clover and tomato as foods for Spodoptera littoralis (Lepidoptera: Noctuidae), on certain biological aspects of the insect were studied under laboratory conditions (25 ± 1°C and ≈70% R.H). The results and statistical analysis showed that all of the biological parameters included in the study were affected by the host plants whereas the shortest larval duration (13.2 ± 0.577 days) was recorded for larvae fed on cabbage and the longer (23.3 ± 0.76 days) resulted when larvae fed with tomato. The pupation percentages on tomato leaves were lowest (58.2 ± 1.79 %) and highest pupation was (86.7 ± 1.36 %) when larvae fed on cabbage leaves. Moreover, adult emergence percentages were (80 ± 0.38 %) in tomato and (98 ± 1.36 %) on cabbage. The numbers of eggs oviposited by female S. littoralis were highest on cabbage, followed by those on the broad bean, clover, and lowest on tomato. Based on the nutritional values of testing host plants proved to be effective in reduced development and reproductive capacity of S. littoralis. Also, results proved that cabbage leaves most favorable host for S. littoralis larvae followed by broad bean leaves. While tomato and clover leaves were the relative unsuitable due to the differences in the leaf nutritional quality as mentioned during phytochemical analysis and the high level of amino acid in the hemolymph of larvae fed on cabbage and broad bean leaves.

Biomarkers Changes Induced in The Mediterranean Fruit Fly, Ceratitis capitata (Wied.) Irradiated by Sterilising And Substerilising Doses of Gamma Radiation

Radiation technology is widely used to produce changes in biosystems. The goal of this work is to determine the variation induced in male parents and F1 Ceratitiis capitata when gamma-irradiated as pupae using substerilising doses (50 and 70 Gy and sterilising dose 90 Gy. Biological studies showed that the percent adult emergence of irradiated pupae decreased as the dose increased and also the percent egg hatchability decreased as the dose increased, also percent pupation and percent emergence of F1 decreased as the dose increased. Comparing DNA (using RAPD-PCR) of untreated adults, adults irradiated with sterilising dose of 90 Gy and parents irradiated with substerile dose (50 and 70 Gy) and their resultant F1. The results revealed that some extra bands appeared and others disappeared, as a result of irradiation. The appearance of extra bands may be due to the repair mechanism of the irradiation damaged DNA. The banding patterns obtained and the dendrograms drawn on the basis of presence and absence of bands revealed that irradiation of parents with 50 and 70 Gy and their F1 are different from the unirradiated pupae It was concluded that the sterile male technique could be used as a benefit tool in controlling Ceratitiis capitata.

Effect of cinnamon oil encapsulated with silica nanoparticles on some biological and biochemical aspects of the rice moth, Corcyra cephalonica (Staint.) (Lepidoptera: Pyralidae)

Bioassays were carried out to evaluate the effect of sub-lethal concentration (LC50) of mesoporous silica nanoparticles (MSNs), cinnamon oil encapsulated with silica nanoparticles (CESN), cinnamon oil and silica gel on some biological parameters of the 6th instar larvae of Corcyra cephalonica. Pupation percentage, pupal duration, percent of adult emergence and adult longevity decreased in all treatments compared with the control. Pupation percentage recorded 47.5, 45.0 and 37.5% after treatment with silica gel, both of MSNs and CESN and cinnamon oil, respectively, compared to 90% in control. CESN and cinnamon oil prevent all pupae from emergence, while the longevity of adult females and males of larvae treated with MSNs and silica gel decreased as compared to control. Furthermore, the protein profile of the treated larvae was evaluated to explain the mode of action of the tested compounds. The total protein contents were 28.88, 28.65, 28.2 and 30.23 mg/ml after treatment with MSNs, CECN, cinnamon oil and silica gel, respectively, compared to 32.56 mg/ml in the untreated control. Electrophoretic analysis of total proteins evaluated inhibitory action of the used compounds on the protein contents, as the appearance as well as the loss of certain protein fractions.

Life-history traits of house fly,Musca domestica L. (Diptera: Muscidae), reared on three manure types

House flies are typically revered as pests because they are a nuisance and carriers of pathogens; however, they are capable of converting animal wastes into valuable biomass that may be suitable for inclusion in animal diets, which has been explored for industrialisation outside of the United States. The purpose of this study was to evaluate the life-history (life cycle) performance, dry matter reduction, and bioconversion of three different manure types fed to house fly larvae. Treatments consisted of 100 1-day-old larvae fed either 9 or 18 g of swine, dairy, or poultry manure every other day until 40% pupation. The control diet (50% wheat bran, 30% alfalfa meal, 20% cornmeal) produced superior results across all parameters examined. When comparing across feed rate for a manure type, larvae weighed more (4-16%) when provided the higher feed rate. A similar trend occurred for pupal (16-25%) and adult (8-25%) weight, as well as adult longevity (7-28%). In regards to those fed manure, significant differences (P<0.05) were detected for time to pupation, percentage pupation, adult weight and adult longevity, dry matter reduction, and bioconversion, across feed rates and manure types. Specifically, among those provided manure, larvae fed poultry manure delivered comparable results to those provided Gainesville diet except for time to pupariation, pupal weight, and percentage pupariation. Data from this study are necessary to advance industrial systems for managing animal wastes with house flies.

Effect of some Insecticides on Pink Bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), Associated Predators in Cotton Field and some of their Biochemical Effects

Efficiency of profenofos, chlorpyrifos and alpha-cypermethrin against Pectinophora gossypiella and their associated predators in cotton field at Zagazig, Sharkia Governorate. Alpha-cypermethrin increased mean seasonal reduction percentages (92.92%), while, profenofos decrease it (78.38%). Alpha-cypermethrin caused the highest mean seasonal reduction percentages in the Coccineledae, Chrysoperla carnea and True spider predators (88.26, 73.67 and 85.70%, respectively). The pupal mortality percentage increased while, pupal duration, adult emergency percentage, pupal weight, pupation percentage, deposited eggs and hatchability percentage decreased. The activity of trehalase, invertase and acetylcholine esterase enzymes decreased but of amylase and AST (Aspartate aminotransferase) increased. Disturbance recorded in ALT (Alanine aminotransferase) enzyme, total lipid and total soluble protein content relative to control.

Study the Toxicity of Three Benzothiazole Compounds Formulated as 10 % Suspension Concentrate against Cotton Leafworm Spodoptera littoralis (Boisd)

Three compounds of benzothiazole were synthetized as active ingredient and prepared as 10 % suspensions concentrate (SC). They were evaluated against the second and fourth instar larvae of the cotton leafworm S. littoralis (Boisd.), under laboratory conditions. LC50 values showed that formulation (1) gave the highest toxic effect against 2nd and 4th instar larvae after 48 hrs from treatment and gave the best effect as antifeedant followed by formulation (3) and formulation (2). Semi field experiment was done to evaluate the initial and latent effects of the formulated compounds compared with commercial insecticide chlorpyrifos 48% EC (Dursban), the results showed that formulation (1) gave 100 % prevention of adult emergency due to the high initial and latent effects and lowest pupation percentage as the same as chlorpyrifos followed by formulation (3) and formulation (2) with the 2nd and the 4th instar larvae. Whereas Formulation (1) at 1 % is already as the same of recommended insecticide chlorpyrifos, therefore it could be recommended to use the new formulations as alternative of hazard conventional insecticides in controlling cotton leafworm in different crops after conducting the other necessary open field experiments.

Isolation and selection of maize plants rhizobacteria with the potential of entomopathogens against Spodoptera litura (Lepidoptera: Noctuidae)

Abstract. Nelly N, Khairul U, Putri AY, Hamid H, Syahrawati MY. 2020. Isolation and selection of maize plants rhizobacteria with the potential of entomopathogens against Spodoptera litura F (Lepidoptera: Noctuidae). Biodiversitas 21: 753-758. Spodoptera litura is a polyphagous pest that can be controlled with entomopathogen. Furthermore, Rhizobacteria derived from the rhizosphere of corn plants are expected to control this pest. This research, therefore, was conducted to obtain the entomopathogenic rhizobacteria to control S. litura derived from the rhizosphere of corn plants. Data sampling was carried out at corn plantations in West Pasaman Regency, while Isolation, selection, and testing of S. litura were conducted at the Biological Control Laboratory of the Plant Protection Department, Faculty of Agriculture, Andalas University. The method uses serial glowing techniques cultured on Nutrient Agar (NA) media, with the selected isolates tested for their ability as an entomopathogen against S. litura. The feed dip method given to S. litura larvae was used to test for rhizobacteria virulence determination with entomopathogen, used to observe the larvae mortality rate, percentage of pupae, and adult formed. Furthermore, observation of morphological and physiological characters was conducted on entomopathogenic rhizobacteria, with hypersensitive testing conducted on Mirabilis jalapa plants. The results of rhizobacterial isolation from corn rhizosphere obtained 12 entomopathogenic isolates. Deadly larvae of S. litura 51-91.11%, 0.00-8.89% pupae, and 0.00- 6.67% adult were formed. The gram test results obtained approximately 8;4 positive (+) and four negative isolates (-), respectively. Hypersensitivity test results found that one of 12 isolates caused necrotic reactions in Mirabilis jalapa. Therefore, a total of 11 rhizobacteria isolates are entomopathogenic and safe to be used as S. litura biological control agents.

The Potential Side Effects of Certain Insecticide Formulations on the Green Lacewing, Chrysoperla carnea (Stephens)

Treated The second larval instar by residual methodindicated that, chlorpyrifos-methyl and methomyl formulations expect Goldben (90.48 % mortality) caused 100 % mortality, while the lowest mortality percent occurred in emamectin benzoate and lufenuron formulations.Except Broact formulation0, there are significant differences between all the tested formulations (ranged from 0.00 to 64.29 % pupation and to 53.57 % adult emergence) and untreated control in pupation (85.71 %) and adult emergence (78.57 %) On the contrary, there are no significant differences between two formulations of each active ingredient except two formulations of emamectin benzoate in pupation percentage only. Treated The second larval instar by feeding method indicated that,chlorpyrifos-methyl formulations is the highly toxic (100 % mortality), when methomyl, emamectin benzoate and lufenuron formulations were low toxic (ranged from 3.70 to 27.27 % mortality) and lufenurononly was high toxic by ingested than leaf residual exposure.. Also, there are highly significant differences between chlorpyrifos-methyl formulations (0.00 % for pupation and adult emergence) with other treatments (ranged from 60.71 to 78.57 % for pupation and from 57.14 to 71.43 % for adult emergence). Treated egg by dipping methodshowed a significant reduction in hatchability rates for formulations of methomyl and chlorpyrifos-methyl ranged from 65.05% (Goldben) to 76.69% (Reldan), however, there are no significant reductions in hatchability rates for formulations of emamectin benzoate and lufenuron, ranged from 86.08% (Broact) to 95.88% (Match) compared to the control (98.33%), but there are not significant differences between two formulations of each active ingredient.

The effect of Tanacetum vulgare essential oil and its main components on some ecological and physiological parameters of Acrobasis advenella (Zinck.) (Lepidoptera: Pyralidae)

Acrobasis advenella (Zinck.) is the most dangerous pest of black chokeberry (Aronia melanocarpa [Michx.] Elliot). The aim of this study was to investigate the insecticidal activity of an essential oil from Tanacetum vulgare (L.) and its main components such as thujone, camphor, and borneol against A.advenella larvae. In addition, the effects of the oil and its main ingredients on the activity of catalase (CAT), polyphenol oxidase (PPO), peroxidase (POX), and α- and β-glucosidases, which are important antioxidants, detoxification enzymes, and digestive enzymes, were examined. Our study showed an increased mortality of larvae and a decrease in the percentage of pupation and emergence of A. advenella moths as well as their longevity. Moreover, we found a significant increase in catalase and polyphenol oxidase activity in larvae feeding on inflorescences treated with T. vulgare EO. The results showed a significant increase in peroxidase assay activity in insects feeding on plants treated with borneol and thujone. However, a significant decrease in peroxidase activity was noted after the use of T. vulgare essential oil. It was shown that the activity of α- and β-glucosidase significantly decreased in larvae fed on inflorescences treated with the essential oil and all substances but the greatest decrease in the activity of α- and β-glucosidase was shown in larvae after thujone treatment. The results suggest that T. vulgare essential oil and its compounds can be useful in protecting organic crops of black chokeberry.

Effect of host plants on biology of Spodoptera littoralis (Boisd.)

An experiment was carried out to evaluate the effect of using different host plants Castor bean, Clover, Cabbage, Broad bean, Sugar beet, and Cotton as foods for Spodoptera littoralis (Boisd.) larvae on certain biological aspects of the insect. The study was achieved under laboratory conditions of (25 ± 1°C) and 75 ± 5 % R.H. for obtained results and statistical analysis cleared that the developmental stages, fecundity, and life parameters were affected by the different hosts whereas the shortest larval duration (18 ± 0 days) was recorded for larvae fed on clover and the longer (25.2 ± 0.37 days) resulted when larvae were offered sugar beet. The pupation percentages on sugar beet leaves were lowest (58.4 ± 2.38 %) and highest pupation percentages were (78.4 ± 1.08 %) when larvae fed on clover leaves. Moreover, adult emergence Percentage was (98 ± 0.45 %) in both clover and broad bean (95.58 ± 0.61 %) on sugar beet. The moths produced from larvae fed on broad bean laid the highest number of eggs (1915 and 1847 eggs per female) in both generations, respectively and the least numbers of eggs deposited were (1081 and 994 eggs/female) on cabbagein the two generations, respectively.

Resistance of Certain Wild Tomato (Solanum spp.) Accessions to Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) Based on Choice and No-Choice Bioassays

The development of cultivars resistant to tomato fruit borer, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), are very limited in Pakistan and other parts of the world because of the lack of good sources of resistance for breeding. Insect-resistant cultivars would be beneficial to decrease the indiscriminate use of pesticides on tomato crops. Seven wild tomato accessions, including Solanum galapagense Darwin & Peralta, Solanum pimpinellifolium L., Solanum cheesmaniae (Riley) Fosberg, and a susceptible check (Solanum lycopersicum L.) (all Solanaceae), were evaluated for resistance to tomato fruit borer based on oviposition preference and feeding in the choice and no-choice bioassays. In the oviposition preference test, S. cheesmaniae (VI037240) and S. galapagense (VI063174) recorded the lowest mean number of eggs, 4.40 and 7.00 per plant, respectively. The highest mortality of H. armigera larvae (90%) was recorded on S. pimpinellifolium (VI030462) compared to the susceptible check (15%). The lowest pupal weight (89.67 mg) resulted from S. galapagense (VI063174), but it was not significantly different from the S. pimpinellifolium and S. cheesmaniae accessions. Among all tested accessions, S. pimpinellifolium (VI030462) was found to be highly resistant to H. armigera based on larval mortality, pupal weight, and pupation percentage. These results can pave the way to enhance the resistance in cultivated tomato varieties to control this notorious fruit borer. Resumen El desarrollo de cultivares resistentes al barrenador de la fruta del tomate, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), es muy limitado en Pakistan y otras partes del mundo debido a la falta de buenas fuentes de variedades resistentes para el fitomejoramiento. Los cultivares resistentes a los insectos serian beneficiosos para disminuir el uso indiscriminado de pesticidas en los cultivos de tomate. Se evaluaron siete accesiones de tomates silvestres, incluyendo Solanum galapagense Darwin y Peralta, Solanum pimpinellifolium L., Solanum cheesmaniae (Riley) Fosberg y un control susceptible (Solanum lycopersicum L.) (todas Solanaceae), para determinar la resistencia al barrenador de la fruta del tomate en base de la preferencia de oviposicion y alimentacion en bioensayos de eleccion y no eleccion. En la prueba de preferencia de oviposicion, S. cheesmaniae (VI037240) y S. galapagense (VI063174) recibieron el numero promedio mas bajo de huevos, 4.40 y 7.00 por planta, respectivamente, en bioensayos de eleccion y de no eleccion. La mortalidad mas alta de larvas de H. armigera (90%) se registro en S. pimpinellifolium (VI030462) en comparacion con el control susceptible (15%). El peso pupal mas bajo (89,67 mg) resulto de S. galapagense (VI063174), pero no fue significativamente diferente de las accesiones de S. pimpinellifolium y S. cheesmaniae. Entre todas las accesiones analizadas, se encontro que S. pimpinellifolium (VI030462) es altamente resistente a H. armigera en funcion de la mortalidad de las larvas, el peso de las pupas y el porcentaje de pupacion. Estos resultados pueden ser un camino para mejorar la resistencia en las variedades de tomate cultivadas para controlar este notorio perforador de frutas. Key Words: tomato fruitworm; wild species; resistance; oviposition; antibiosis; mortality View this article in BioOne

Evaluation of the Effectiveness of Some Entomopathogenic Fungi on the Greater Wax Moth Larvae, Galleria mellonella (L.) (Lepidoptera: galleriidae)

The present study designed to investigate the effect of three entomopathogenic fungi (EPF), Beauveria bassiana (Biovar), Trichoderma album (Biozed) and Metarhizium anisopliae (Bioranza) on greater wax moth Galleria mellonella larvae. The results revealed that the LC25 values of T. album, M. anisopliae and B. bassiana against G. mellonella larvae were 14.08, 44.20 and 57.82 ppm, respectively. The LC50 were 104.03, 252.55 and 389.05 ppm, respectively for the same biocides. T. album was the most toxic biocide for controlling G. mellonella larvae, While B. bassiana was the least toxic one. The slope of the tested compounds was 0.78, 0.89 and 0.81 for T. album, M. anisopliae and B. bassiana, respectively. The toxicity index of the tested compounds was 24.35 & 26.74 & 31.85 and 41.18, respectively. On the other hand, the relative potency of the three tested compounds at LC25 and LC50 were 1.31 & 1.54 and 4.11 & 3.74 fold for both M. anisopliae and T. album compared to 1.00 fold in case of B. bassiana. The results showed that the cumulative mortality percentages of G. mellonella larvae treated with the three products can be arranged according to the most efficient compounds 47.61, 41.52 and 39.67%, respectively for T. album, M. anisopliae and B. bassiana compared to control. Also, the results indicated that three tested biocides have a significant effect on some biological aspects of G. mellonella larvae. B. bassiana was the most effective biocide on larval and pupal duration, pupal mortality, pupal weight and sex ratio percentages. While, treatment with M. anisopliae reduced male longevity, and the malformation percentages recorded as 27.35% compared to control. But, T. album had the most toxic effect on accumulative larval mortality, pupation percentages, pupal duration and significantly decreased the female sex ratio than control. The three tested biocides had an effect on some biochemical parameters of G. mellonella larvae. The activity of amylase enzyme had a significantly decreased effect after five periods of treatment compared to control. A significant increase in relative activity in protease enzyme was recorded after treatment with the three EPF. A fluctuation in the enzyme activity of transaminase enzymes, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) was estimated. There was also a significant reduction in total protein content. Results cleared that, significantly increased gradually in total lipid up to ten days after treatments. The results indicated that the tested bio-products can be used in honey bee colonies as a strategy to control G. mellonella larvae as one of the components of biological control programs.

Development and application of a quantitative bioassay to evaluate maize silk resistance to corn earworm herbivory among progenies derived from Peruvian landrace Piura.

Corn earworm (CEW), Helicoverpa zea (Boddie), (Lepidoptera: Noctuidae), is a major insect pest of corn (Zea mays spp. mays L.). CEW larvae feed on silks, kernels and cobs, causing substantial yield and quality losses both through herbivory and by vectoring pathogens. The long-term goal of this work is to elucidate the genetic and biochemical basis of a potentially novel CEW resistance source discovered in silk tissue of Piura 208, a Peruvian landrace of maize (PI 503849). We developed a quantitative CEW bioassay and tested it on four populations that contrast alleles from Piura 208 with those from GT119, a CEW-susceptible maize inbred line. In replicated analyses of two populations of F1:2 families, corn genotype accounts for 84% and 68% of the variance in CEW larval weights, and up to 60% of the variance in CEW pupation percentage, demonstrating both the success of the quantitative bioassay and the strength of the Piura 208 resistance mechanism. Analyses of two corresponding populations of BC1:2 families revealed substantially diminished effects of corn genotype on CEW weight gain and pupation. This loss of Piura 208-derived CEW resistance during backcrossing suggests complex (multi-genic) inheritance of a threshold-dependent mechanism. Technical factors in bioassay performance were also assessed, often by analyzing the 1,641 CEW larvae that were raised on control diet (meridic with no corn silks added). Minor, but statistically significant impacts on CEW weight gain, pupation, and mortality were attributable to multiple technical factors in the preparation, incubation and evaluation phases of the bioassay, demonstrating the importance of randomization, stratification, replication, and variable-tracking across the many steps of this quantitative CEW bioassay. Overall, these findings indicate that this scaled-up, quantitative CEW bioassay is fundamentally sound and that Piura 208-derived resistance alleles are experimentally tractable for genetic and mechanistic research using this approach.

Comparative Activity of Commercial Baculovirus Formulations against Heliothine Pests of Cotton

Nuclear polyhedrosis viruses have been labeled for use as microbial insecticides in agronomically-important crops in the U.S. since the 1970s. New products developed from viral isolates of different species in the heliothine genera Helicoverpa, Heliothis, and Chloridea have been introduced to the market and are receiving renewed attention for controlling heliothine pests. Two laboratory assays were used to evaluate comparative activities among the first nuclear polyhedrosis viruses registered in the U.S. and two commercially-available baculovirus products for controlling bollworm, Helicoverpa zea (Boddie), and tobacco budworm, Chloridea virescens (F.). Based on comparisons of LC50s of formulated products from laboratory overlay assays at 7 days, Gemstar was 2.4 and 3.7 fold less active than Elcar against bollworm and tobacco budworm, respectively. Heligen was 2.9 and 7.1 fold more active than Elcar against bollworm and tobacco budworm, respectively. However, once corrected for concentration of polyhedral occlusion bodies, susceptibility of bollworm did not differ to any of the three products tested. Tobacco budworms were more susceptible to Heligen than Gemstar in laboratory overlay assays following correction for differences in concentration of polyhedral occlusion bodies, which might be caused by interrelatedness of the species with the Old World bollworm. No discernable difference in death of bollworms or tobacco budworms was detected among the greatest labeled rate of any formulated microbial insecticide sprayed on leaves of non-Bt cotton (Gossypium hirsutum L.) at 14 days and percentage of pupation at 20 days post-treatment. Although the activity of wild-type baculovirus has changed little during the past four decades, use of the products should be encouraged whenever possible. Potential ecological benefits of preserving beneficial insects and reducing selection for resistance to insecticides should be promoted as long as effectiveness and costs are reasonable.

Toxicity and developmental effect of cucurbitacin E from Citrullus colocynthis L. (Cucurbitales: Cucurbitaceae) against Spodoptera litura Fab. and a non-target earthworm Eisenia fetida Savigny.

Pest management with natural botanical insecticides is a significant implementation for the sustainability of agroecosystem by reducing the unnecessary risk from the inputs of synthetic insecticides. In this research, we isolated the bioactive compound cucurbitacin E from Citrullus colocynthis (L.) Schrad, and their toxicological effects were screened against different larval instars of Spodoptera litura. The bioactive compound cucurbitacin E was chemically characterized through TLC, FT-IR, and NMR analyses. The larval mortality bioassay revealed that the larvae exposed to cucurbitacin E at the discriminating dose of 50ppm display higher mortality rate against second (93.8%), third (86.4%), and fourth (73.2%) instar respectively. The lethal concentrations (LC50 and LC90) was detected as 15.84 and 67.60ppm for third instar respectively. The sub-lethal concentration of cucurbitacin E (2, 4, and 6ppm) intentionally altered the percentage of survival, pupation, fecundity, and egg hatchability of S. litura. Moreover, antifeedant activity of cucurbitacin E was analyzed using choice-based test. In addition, we found the toxic effects of cucurbitacin E (50 and 100ppm) and chemical pesticides (cypermethrin and monocrotophos) against terrestrial beneficial earthworm Eisenia fetida, and the result revealed that cucurbitacin E has no harmful effect on non-target organism. Hence, the present study reveals that cucurbitacin E might be a part of a new biorational product alternative to synthetic pesticides.

EFIKASI INSEKTISIDA NABATI EKSTRAK BUNGA KEMBANG BULAN (Tithonia diversifolia A. Gray) TERHADAP HAMA ULAT GRAYAK (Spodoptera litura F.) PADA TANAMAN SAWI DI LABORATORIUM

Armyworm (Spodoptera litura) is one of the pests that attack vegetable plants in Indonesia. The attack resulted in the leaves of the plant being cut and perforated so as to reduce productivity and even crop failure The aim of the study was to determine effectiveness of Tithonia diversifolia extract as a vegetable insecticide to control the Spodoptera litura in mustard plants at the laboratory. The study used a completely non-factorial randomized design consisting of 5 treatments, K0 = no extract (control), K1 = concentration 4%, K2 = concentration 6%, K3 = concentration 8%, K4 = concentration 10%. Parameters observed were morphological changes and insect behavior, percentage of larval mortality, percentage of pupae and imago formed. The results that Tithonia diversifolia extract can control Spodoptera litura. The result of 8% (K3) Tithonia diversifolia extract effectively controls Spodoptera litura. The highest percentage of larval mortality of Spodoptera litura (80%) was found in the treatment of K3 (concentration 8%) at observation 9 HSA and the lowest mortality was found in K1 (concentration 4% with an average 67.5%. The lowest formation of pupa and imago in the K3 treatment was 20 and 29.17%

Influence of Thuja Essential Oil on Untreated Larvae and F1 Generation Larvae of Galleria mellonella Irradiated with Gamma Radiation

The objective of the current study was to determine the fumigant toxicity of Thuja essential oil against 3rd and 5th instar larvae of the greater wax moth, Galleria mellonella. Thuja essential oil was extracted from unripe fruits of Thuja orientalis plant by water distillation. The mortality of larvae at the end of larval period, pupation and adult emergence were tested at different concentrations of Thuja oil after a 24h exposure period ranging from 5 to 25µL for 3rd instar larvae and 80µL for 5th instar. The combined effect of Thuja essential oil and larvae resulting from parents irradiated as pupae of G.mellonella with 80Gy was investigated. The results demonstrated that the mortality increased by increasing oil concentration. The percent mortality of 3rd instar larvae reached 100% when exposed to a higher concentration of Thuja oil (25µL) after 24h, while in the case of 5th instar larvae the mortality was 73.3% at (80µL). Larvae of both instars resulting from parents of G. mellonella irradiated as pupae with 80Gy and exposed to the same concentrations of Thuja oil vapor became more susceptible to the oil as a result of the combined effect of the two agents. The LC50 and LC90 values for each experiment were calculated. The tested plant oil prolonged the larval - pupal periods and reduced both pupation percentage of adult emergence.

Purified winged bean protease inhibitor affects the growth of Bactrocera cucurbitae.

The melon fruit fly, Bactrocera cucurbitae (Coquillett), is a serious agricultural pest which has defied the various control measures employed against it. Protease inhibitors present in plants which have the potential to inhibit the growth and development of associated insect pests can be a possible alternative which can be manipulated for developing resistance in plants to the pest. In the present study, winged bean (Psophocarpus tetragonolobus) protease inhibitor isolated through affinity chromatography was explored for its potential to disrupt the development of melon fruit fly, B. cucurbitae. Different concentrations (12.5, 25, 50, 100, 200, and 400 µg ml-1) of the winged bean protease inhibitor (WBPI) were incorporated into the artificial diet of the second instar (64-72 h old) larvae of B. cucurbitae. The WBPI significantly delayed the larval, pupal, and total development period. The percentage pupation and adult emergence of the treated larvae was reduced as compared with control. The activities of major digestive enzymes (trypsin, chymotrypsin, leucine aminopeptidase, and elastase) decreased significantly in the larvae treated with different concentrations (50, 100, 200, and 400 µg ml-1) of WBPI. The findings reveal that the inhibitor holds considerable promise for the management of the melon fruit fly.

Some Natural Plant Extracts Having Biocide Activities against the American Bollworm <i>Helicoverpa armigera</i> (Lepidoptera: Noctuidae)

In the present research, the toxicity, antifeedant activity and biological effects of ethanolic leaves extract of four medicinal plants named Eucalyptus rostrata, Dodonea viscosa, Rhyza stricta and Cymbopogon schoenanthus were evaluated on 2nd, 3rd and 4th instar larvae of H. armigera under laboratory condition. The results showed that values of LC50 in mg of different plant extracts in mg/100ml of the larval diet can be arranged in an ascending order as follows: Dodonea 7.23 > Cymbopogon 12.59 > Rhazya 14.52 > Eucalyptus 29.42 mg/100ml diet (the least LC50 is more toxic than the higher one). All the tested extracts had antifeedant and starvation effects against the 2nd, 3rd, 4th instar larvae. D. viscose extract possesses the least antifeedant effect even of their higher toxicity. There was clear relation between the percent of starvation and antifeedant of the 2nd, 3rd and 4th larval instar. All extracts were nearly the same in their effect on the biotic potential; of the insect, and possess latent effect when tested against 2nd instar larvae, the value of LC 50 of the extract was added to the diet, extracts increased larval duration, deformation between pupae and adult stages, moths sterility, increased as decreasing in females egg production. Other effects were noticed, reduction in percentage of pupation and moths emergence. The plant extracts can be arranged ascending according to percentage of their sterility effects as follows: C. schoenanthus < E. rostrata < R. stricta < D. viscose. All extracts cause disruption on the biology and physiology of the insect, and all extract induced percentages of deformation between pupal and moth stages. The ethanolic extract of the plant leaves of the tested plans may be used for control H. armigera in combination with other methods in the integrated program in order to decrease the buildup of the resistance and protect the environment from chemical pollution.

Bahasa indonesia

Beauveria bassiana is one of the entomopathogenic fungi to control various kinds of insect pests. Virulence of B. bassiana against insects could be affected by ultraviolet (UV) light. The study was aimed to determine the effect of different times of UV light exposure to B. bassiana against Spodoptera litura. The study was arranged in a Completely Randomized Design (CRD) with six different times of UV light exposure (control, 0, 15, 30, 45, 60 minutes) in four replications, respectively. Those B. bassiana were inoculated on the second instar of larvae of S. litura. The parameters observed were colony growth of B. bassiana, conidial germination, larval mortality, percentage of pupae, and adults formed. The data were analyzed by analysis of variance and LSD test at the 5% significance level. The results showed that exposure of B. bassiana to UV light reduced its germination but not inhibit the growth of B.bassiana. The exposure for 45 minutes and 60 minutes increased the virulence of B. bassiana that indicated by an increase of S.litura mortality (15.0-62.5%) and shorter LT50 (6.29-10.92).