scholarly journals Neochrysocharis okazakii(Hymenoptera: Eulophidae) as a Major Parasitoid Wasp of Stone Leek Leaf MinerLiriomyza chinensis(Diptera: Agromyzidae) in Central Vietnam

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Takatoshi Ueno ◽  
Dang Hoa Tran
Keyword(s):  
Field Survey ◽  
Host Density ◽  
Parasitoid Wasp ◽  
Leaf Miner ◽  
Welsh Onion ◽  
Leaf Miners ◽  
Central Vietnam ◽  
Major Pest ◽  
The Mean ◽  
Parasitoid Aggregation

Liriomyza chinensisis a major pest of Welsh onionAllium fistulosumin Asia but little is known about the abundance of its natural enemies. A field survey was made to explore the major parasitoids ofL. chinensisleaf miner in central Vietnam. An eulophid parasitoid,Neochrysocharis okazakii,comprised more than 95% of parasitoids reared from leaf miner larvae collected in the onion field and 98.3% of leaf miner parasitoids found during searches of onion plants. The mean number of femaleN. okazakiion plants was greater in onion fields with a higher density ofL. chinensis, and, during searches, a greater proportion ofN. okazakiiwas found on onion with moreL. chinensismines, suggesting density-dependent parasitoid aggregation. Melanized dead larvae ofL. chinensiswere more frequently found in onion fields with more parasitoids, demonstrating that melanized leaf miners are a good indicator of parasitoid activity. Mean instant rate of host encounter byN. okazakiiin the field was estimated at 0.077, and the likelihood of a parasitoid finding a host increased with host density. Taken together, these results show thatN. okazakiiis the major parasitoid ofL. chinensis. Usefulness of this parasitoid in stone leek leaf miner management is discussed.

Sublethal effects of organophosphorus insecticide phoxim on patch time allocation and oviposition behavior in a parasitoid wasp Meteorus pulchricornis

2021 ◽  
pp. 1-10
Author(s):  
Sheng Sheng ◽  
Yan Song ◽  
Sheraz Ahmad ◽  
Jiao Wang ◽  
Ying Shao ◽  
...  
Keyword(s):  
Time Allocation ◽  
Sublethal Effects ◽  
Insect Pests ◽  
Oviposition Behavior ◽  
Host Density ◽  
Parasitoid Wasp ◽  
Patch Time Allocation ◽  
Meteorus Pulchricornis ◽  
Allocation Decisions ◽  
Patch Residence Time

Abstract Parasitoid wasps are key agents for controlling insect pests in integrated pest management programs. Although many studies have revealed that the behavior of parasitic wasps can be influenced by insecticides, the strategies of patch time allocation and oviposition have received less attention. In the present study, we forced the endoparasitoid Meteorus pulchricornis to phoxim exposure at the LC30 and tested the foraging behavior within patches with different densities of the host, the larvae of the tobacco cutworm Spodoptera litura. The results showed that phoxim treatment can significantly increase the patch-leaving tendency of female wasps, while host density had no impact. The number of oviposition and the number of previous patch visits also significantly influenced the patch time allocation decisions. The occurrence of oviposition behavior was negatively affected by phoxim exposure; however, progeny production was similar among patches with different host densities. Phoxim exposure shaped the offspring fitness correlates, including longer durations from cocoon to adult wasps, smaller body size, and shorter longevity. The findings of the present study highlight the sublethal effects that reduce the patch residence time and the fitness of parasitoid offspring, suggesting that the application of phoxim in association with M. pulchricornis should be carefully schemed in agroecosystems.

scholarly journals Impact of Weather Factors on Coelaenomenodera elaiedis MLK (Coleoptera: Chrysomelidae) in Nigeria

2020 ◽  
pp. 115-128
Author(s):  
Aneni T. I. ◽  
Adaigbe V. C. ◽  
Ogbebor C. O. ◽  
Okere C. I. ◽  
Aghayedo C. O.
Keyword(s):  
Relative Humidity ◽  
Oil Palm ◽  
Insect Pests ◽  
Leaf Miner ◽  
Weather Factors ◽  
Fresh Fruit Bunch ◽  
Major Pest ◽  
Model Equations ◽  
Main Station ◽  
Mathematical Relationships

The leaf miner (Coelaenomenodera elaeidis) is a major pest of the oil palm. It breaks out in epidemic proportions periodically, resulting in severe leaf defoliation and consequently low fresh fruit bunch (FFA) yield. This study analyses temperature, rainfall, relative humidity, and leaf miner abundance records sampled in oil palm fields between 1976 and 1980 in the main station of the Nigerian Institute for Oil Palm Research (NIFOR). Data for temperature, rainfall, and relative humidity were obtained from NIFOR meteorological station. Mathematical relationships between the insect stages (larva, pupa, and adult) and weather factors (rainfall and temperature) were developed indicating that pest predictions can be made for different leaf miner stages using their corresponding model equations giving specific values for rainfall and temperature. Variations in the seasonal patterns of temperature and rainfall are of major significance as a cue to timing leaf miner abundance and would help in making better decisions regarding where farmer action can target pest control interventions, thereby contributing to ensure food security. The need for continuous monitoring has great potential for detection and control of insect pests in oil palm growing areas.

scholarly journals Reproductive efficiency of the bethylid waspCephalonomia tarsalis:the influences of spatial structure and host density

2016 ◽  
Vol 107 (2) ◽  
pp. 139-147 ◽  
Author(s):  
P.A. Eliopoulos ◽  
A. Kapranas ◽  
E.G. Givropoulou ◽  
I.C.W. Hardy
Keyword(s):  
Spatial Structure ◽  
Host Density ◽  
Parasitoid Wasp ◽  
Mass Rearing ◽  
Mutual Interference ◽  
Host Population ◽  
Biological Pest Control ◽  
Offspring Production ◽  
Chemical Studies ◽  
High Degree

AbstractThe parasitoid waspCephalonomia tarsalis(Ashmead) (Hymenoptera: Bethylidae) is commonly present in stored product facilities. While beneficial, it does not provide a high degree of biological pest control against its host, the saw-toothed beetleOryzaephilus surinamensis(L.) (Coleoptera: Silvanidae). A candidate explanation for poor host population suppression is that adult females interfere with each other's foraging and reproductive behavior. We used simple laboratory microcosms to evaluate such mutual interference in terms of its overall effects on offspring production. We varied the density of the hosts and also the spatial structure of the environment, via the extent of population sub-division and the provision of different substrates. Production ofC. tarsalisoffspring was positively influenced by host density and by the isolation of females. With incomplete sub-division within microcosms offspring production was, in contrast, low and even zero. The provision of corrugated paper as a substrate enhanced offspring production and partially mitigated the effects of mutual interference. We recommend simple improvements to mass rearing practice and identify promising areas for further behavioral and chemical studies towards a better understanding of the mechanisms of mutual interference.

The dynamics of infection of Tribolium confusum by Hymenolepis diminuta: the influence of exposure time and host density

Parasitology ◽  
1982 ◽  
Vol 84 (1) ◽  
pp. 157-166 ◽  
Author(s):  
Anne Keymer
Keyword(s):  
Exposure Time ◽  
Parasite Burden ◽  
Host Density ◽  
Faecal Pellet ◽  
Experimental Results ◽  
Hymenolepis Diminuta ◽  
Parasite Transmission ◽  
Experimental Conditions ◽  
Instantaneous Rate ◽  
The Mean

SUMMARYSurvival of Hymenolepis diminuta eggs (as measured by their infectivity to the intermediate host) was found to be age-dependent with an expected value of 11 days when the eggs were retained within the faecal pellet at 10 °C. The expected life-span of eggs under experimental conditions (i.e. extracted from faecal material and placed on filter paper at 30 °C) was estimated as 33 min. The mean parasite burden of populations of Tribolium exposed to known densities of H. diminuta eggs was found to rise to a plateau with increasing exposure time. The experimental results provided a method of estimating the instantaneous rate of parasite transmission: a value of 0·0004/egg/min/host/13 cm2 was obtained. The mean parasite burden of populations of T. confusum exposed to known densities of H. diminuta eggs was found to decrease exponentially with increasing host density. A second estimate of the instantaneous rate of parasite transmission of 0·004/egg/min/host/13 cm2 was obtained from the experimental results. No differences in susceptibility to infection between 2-week-old male and female beetles were found. A marked decrease, however, was apparent with increasing beetle age up to 14 weeks post-eclosion.

Annual variations of dry-season populations of larvae of Busseola fusca (Fuller) in Northern Nigeria

1964 ◽  
Vol 54 (4) ◽  
pp. 643-647 ◽  
Author(s):  
K. M. Harris
Keyword(s):  
Crop Residues ◽  
Busseola Fusca ◽  
Dry Season ◽  
Research Station ◽  
Northern Nigeria ◽  
Sampling Area ◽  
Annual Variations ◽  
Random Samples ◽  
Major Pest ◽  
The Mean

The larval populations of Busscola fusca (Fuller), a major pest of the guineacorn (Sorghum vulgare) crop, which survive the dry season in and around villages near the Research Station, Samaru, Northern Nigeria, were assessed by sampling. The larvae of B. fusca survive the five to six rainless months in diapause in crop residues, most important of which are guineacorn stems, which are stacked in the fields after harvest. Between 1956 and 1962, 100-stem random samples were collected from as many stacks as possible within an area of about six square miles. Each of the 348 samples was dissected immediately after collection and the number of living larvae of B. fusca per sample was recorded. The mean number of larvae per sample varied annually and ranged from 7 in the 1960–61 dry season to 33 in the 1959–60 dry season. The mortality of larvae is comparatively low between January and March, when most samples were collected, and it is concluded that the date of sampling did not unduly influence the estimates of annual variations of the population. The location of sampling areas also had surprisingly little effect and, despite uneven growth of the crop, the estimates of larval populations were remarkably uniform throughout the ten sampling areas and between samples within the main sampling area of Bomo village.It is concluded that there is considerable variation in dry-season populations from year to year. The factors causing this variation have not been determined, and it is suggested that other workers might profitably continue and expand these investigations.

Laboratory studies of insecticides against the coffee leaf-miner Leucoptera Meyricki Ghesq. (Lepidoptera, Lyonetiidae)

1963 ◽  
Vol 54 (2) ◽  
pp. 167-174 ◽  
Author(s):  
P. E. Wheatley
Keyword(s):  
Methyl Parathion ◽  
Field Trials ◽  
Leaf Miner ◽  
Laboratory Studies ◽  
Leaf Miners ◽  
Larval Stages ◽  
Air Stream ◽  
Bioassay Technique ◽  
Coffee Leaf Miner ◽  
Future Date

The coffee leaf-miners Leucoptera meyricki Ghesq. and L. caffeina Wshbn. are serious pests of arabica coffee in Kenya. At the present time sprays containing parathion, methyl-parathion or diazinon are used extensively for their control.To facilitate preliminary investigations into various aspects of insecticidal control of the larval stages of these pests, a laboratory bioassay technique was developed. Larvae were reared on detached coffee leaves placed on moist filter paper in plastic boxes. When the larvae were in their third instar, the leaves were sprayed in a Potter tower and then kept in a moist air stream for three days before the mines were dissected to enable mortality counts to be made.Of 22 new insecticides screened, only Sumithion (O, O–dimethy1 O–(3–methy1–4–nitrophenyl) phosphorothioate) and fenthion gave mortalities higher than those achieved with diazinon. Parathion gave somewhat higher mortalities than methyl-parathion, and emulsifiable formulations of these insecticides were more effective than wettable powders. The inclusion of additional wetting agents increased the efficiency of commercial formulations of these two insecticides. These results are subject to confirmation in field trials.The mode of action of parathion was investigated. Dosage/mortality lines were constructed for parathion, methyl-parathion and diazinon so that resistance to these insecticides by L. meyricki could be detected should it develop at some future date. L. caffeina was found to be apparently more susceptible to these insecticides than L. meyricki and this was believed to be due to its greater rate of feeding.

scholarly journals Species richness and abundance of native leaf miners are affected by the presence of the invasive horse-chestnut leaf miner

2009 ◽  
Vol 12 (5) ◽  
pp. 1011-1021 ◽  
Author(s):  
Christelle Péré ◽  
Sylvie Augustin ◽  
Rumen Tomov ◽  
Long-hui Peng ◽  
Ted C. J. Turlings ◽  
...  
Keyword(s):  
Species Richness ◽  
Leaf Miner ◽  
Horse Chestnut ◽  
Leaf Miners ◽  
Species Richness And Abundance ◽  
Chestnut Leaf

scholarly journals Arthropod Pests and Tomato Value Chain: Review of Research Cocktails in Nigeria

2020 ◽  
pp. 1-8
Author(s):  
Adeola Abiola Oso
Keyword(s):  
Value Chain ◽  
Leaf Miner ◽  
Economic Damage ◽  
Yield Reduction ◽  
Leaf Miners ◽  
Government Interventions ◽  
Self Sufficiency ◽  
Fruit Borer ◽  
Arthropod Pests ◽  
Nutritional Benefits

Background: Tomato is an essential and remunerative staple food widely grown and consumed in all parts of Nigeria. The northern parts of the country produce ninety-eighth percent of the tomatoes consumed annually. However, higher percentages of tomatoes produced in these regions are lost due to gaps recorded in its value chain. Principal Findings: Tomato value chain needs to be strengthened from production to processing, preservation and good marketing structure. Challenges bedevilling tomato value chain in Nigeria include poor accessibility to production inputs such as seeds, nurseries, fertilizers; poor packing systems and transportation problems; marketing challenges and yield reduction caused by a complex of arthropod pests attacking the crop. The major arthropod pests inflicting economic damage on tomato include fruit borer, whitefly, aphid, thrips and leaf miners. Interventions: Considering the Nigerian Government’s recent interventions: “close border”, increased tariffs on the importation, and different incentives such as “tax holiday” and introduction of zero percent import duty on greenhouse equipment, soft loans through Bank of Agriculture as well as a national collaborative effort against the menace of tomato leaf miner (Tuta absoluta) invasion; How much of these interjectory efforts have translated to the realization of national self-sufficiency in the tomato value chain? Conclusion: This paper highlights the general introduction of tomato, its botany, nutritional benefits, tomato value chain in Nigeria, Nigerian government interventions towards its sustainability with particular focus on research cocktails at combating the problems of arthropod pests on the tomato to identify the probable critical solutions to these harmful pests.  

scholarly journals Population of Spodoptera exigua Hübner during On- and Off-Season of Shallot in Bantul Regency, Yogyakarta

2019 ◽  
Vol 23 (2) ◽  
pp. 261
Author(s):  
Fitri Ujiyani ◽  
Y. Andi Trisyono ◽  
Witjaksono Witjaksono ◽  
Suputa Suputa
Keyword(s):  
Spodoptera Exigua ◽  
Beet Armyworm ◽  
Pheromone Traps ◽  
Welsh Onion ◽  
Major Pest ◽  
Polyphagous Insect ◽  
Surrounding Areas ◽  
Lepidoptera Noctuidae ◽  
Planting Season

Beet armyworm (Spodoptera exigua Hübner) (Lepidoptera: Noctuidae) is known to be a polyphagous insect that infests many crops such as welsh onion, maize, tobacco, cotton, and others. In Indonesia, this species is a major pest of shallot. The study was aimed to monitor the population of beet armyworm in the shallot plantation in Bantul Regency, Yogyakarta. The monitoring was conducted using pheromone traps containing Z-9-tetra decanol 10 µg/rubber unit and Z-9-tetradecadienyl 90 µg/rubber unit. The pheromone was placed in the fields to trap males during on- and off-shallot plant season. The sites for placing the pheromone traps were selected in the farms where shallot was planted once and twice per year. The selected sites were with shallot and non-shallot in their surrounding areas. The result showed that males emerged both on- and off-shallot planting seasons in most of the areas. The average number of trapped males during the shallot season was < 5 males/trap/week. The number increased and reached the peak (7.33 males/trap/week) in June until July which was the off-shallot season. The population reduced to < 2 males/trap/week at the end of second shallot planting season until end of the year where the fields were mostly planted with rice. These findings indicate that the beet armyworm presents all year around with or without shallot in the fields. It suggests that management of this insect should be done not only during the shallot season but also the remaining seasons to obtain more effectiveness.

scholarly journals Seasonal diversity of entomofauna, their impact and management practices in tomato fields in Meru district, Tanzania

2021 ◽  
Vol 21 (04) ◽  
pp. 17952-17971
Author(s):  
Gabriel Michael ◽  
◽  
AMS Nyomora ◽  
EF Mvungi ◽  
EM Sangu ◽  
...  
Keyword(s):  
Bemisia Tabaci ◽  
Management Practices ◽  
Insect Pests ◽  
Insect Pest ◽  
Tomato Leaf ◽  
Tuta Absoluta ◽  
Leaf Miner ◽  
Yield Reduction ◽  
Leaf Miners ◽  
Frequent Application

Tomato is a highly cultivated vegetable in Tanzania. The intensive tomato cultivation and production in Tanzania has resulted in high pests and diseases build-up. A survey to identify and quantify entomofauna diversity in different seasons and pest management practices in Meru District was conducted. In addition, a laboratory experiment was done to assess the effectiveness of commonly used pesticides SnowBecco (Thiamethoxam)and Belt (Flubendiamide) against two dominating insect pests, white flies (Bemisia tabaci (Gennadius, 1889)) and leaf miner (Tuta absoluta (Meyrick, 1917)), respectively. The results obtained revealed that, tomato fields in Meru District had significantly higher entomofauna build up during dry season than the rainy season (U0.05 (df, 24)= 45, p = 0.0441). More than 70% of all collected entomofauna were dominated by the whiteflies (Bemisia tabaci) and tomato leaf miners (Tuta absoluta) belonging to orders Hemiptera and Lepidoptera, respectively. It was also observed that, the common pesticides management practices were the use of pesticidal cocktail, broad spectrum insecticides, use of botanical pesticides, frequent application of pesticide and insecticides over dosage. Moreover, yield reduction due to whiteflies and tomato leaf miners infestation were observed in terms of reduced fruits number per plant (38 and 18.4%), fruit size (22.4 and 14.2%), and fruits weight per plant by 43.6 and 26.2%, for Bemisia tabaci and Tuta absoluta, respectively. The study showed that the recommended doses in both tested insecticides caused significant pest mortality (F0.05 (df, 19) = 4.367, p = 0.0199) and (F0.05(df, 19) = 4.761, p = 0.0147) for B. tabaci and T. absoluta, respectively, within a specified period of time. The results suggest that high insect pest infestations could be caused by factors other than development of insecticidal tolerance including inappropriate identification of insect pests due to lack of training, and inappropriate selection and application of insecticides. Consequently, frequent application of broad spectra insecticides not only increases production expenses but also disrupts agroecosystem by killing beneficial entomofauna and disrupting soil organisms that are susceptible to insecticide toxicity.

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