Geostatistical characterization of fruit damage caused by Anarsia lineatella (Lepidoptera: Gelechiidae) in organic fruit orchards and implications for its management

The peach twig borer Anarsia lineatella is the most common pest threat of peaches worldwide. This work studies for the first time, the fruit damage patterns inside organic peach orchards using geostatistical methods. A linear semivariogram model provides the best fit among candidates’ linear and non-linear models based on the RSS and r². Moreover, the shape of the linear model approaches the pure nugget effect model, with a very low correlation between samples regardless of the distance of separation. This suggests either that the caused damage is to a high degree randomly or uniformly distributed, or, that autocorrelation may be present in distance lower than the measured distance of the study orchards. The linear model has been used for Kriging interpolation to simulate the spatial distribution of fruit damage and to indicate hot spots of high pest activity. According to the linear interpolation model, the simulated percentage of damage ranged from 12% to 28% during an observation period of three years. Moreover, slight border effects were observed during the first two years of observation suggesting possible entry of individuals from nearby orchards.     

First record of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Burundi

This study to detect Tuta absoluta was carried out at four sites in western Burundi from March to July 2018. Delta traps containing Tutrack pheromone and sticky paper were installed in tomato fields at 40 cm from the ground. Sample collection was carried out twice a week. The results confirmed the presence of T. absoluta in Burundi. Effective pest control is required to avoid heavy losses on tomato production.     

番茄潜叶蛾成虫卵巢发育与卵子发生研究

明确雌成虫的卵巢发育及其卵子发生有利于害虫发生期和发生量的准确预测及其防治适期的确定。本研究在观察重大外来入侵害虫番茄潜叶蛾Tuta absoluta雌成虫生殖系统结构和卵巢发育级别的基础上,进一步比较了营养条件和是否交配处理,即未交配+清水、未交配+20%葡萄糖溶液、交配+清水、交配+20%葡萄糖溶液条件下番茄潜叶蛾的卵子发生动态。结果显示：雌成虫生殖系统主要包括卵巢、输卵管、附腺、交配囊、阴道支囊、受精囊及受精囊腺等组织;左右两侧卵巢的卵巢管数大多相等,各含4根卵巢管;卵巢发育进度可分为卵黄沉积前期(Ⅰ级)、卵黄沉积期(Ⅱ级)、成熟待产期(Ⅲ级)、产卵盛期(Ⅳ级)和产卵末期(Ⅴ级)5个级别。雌成虫只取食清水也可持续形成成熟卵子,未交配雌虫卵子数量于羽化72 h达到高峰,发育至96 h时显著减少,并观察到卵子重吸收现象。取食20%葡萄糖溶液可显著促进雌虫的卵子发生,其成熟卵子、总卵子数在羽化后24 h均显著多于取食清水;雌虫发生卵重吸收后,补充取食20%葡萄糖溶液,卵巢内各类卵子数显著增加。交配对雌成虫卵子发生有明显促进作用,取食20%葡萄糖溶液或清水的交配雌虫,羽化96 h后,成熟...     

First record of the tomato leafminer,Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Sudan

An outbreak of larvae and adults of a devastating moth was noted to be causing severe damage in tomato grown in greenhouses at Khartoum State, Sudan during June 2010. Symptoms included foliage mining and leaves drying. Photographs of symptoms and larvae and adults of the pest (and subsequently specimens) were sent to Russell IPM, UK and the Finnish Museum of Natural History for identification. The pest was identified as Tuta absoluta (Meyrick), (Lepidoptera: Gelechiidae). This is the first official record of T. absoluta in Sudan, based on surveys in tomato production areas in Khartoum, Gezira, Red Sea and North Kordofan States and eggplant and potato in Khartoum State. Severe yield loss due to the serious feeding damage on foliage and fruits infestation was reported on tomato and eggplant fields at Khartoum State.     

Tuta absoluta (Meyrick) (Lepidoptera,Gelechiidae) in the Republic of Srpska (Bosnia and Herzegovina)

Pheromone traps were placed in the market place in Banja Luka, and in greenhouses and open field tomato crops, on 13 September 2010 to determine the presence of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Banja Luka region. Based on examination of traps, the presence of T. absoluta was confirmed for the first time in the Republic of Srpska. Only mines of Liriomyza species were found by examining leaves under a stereomicroscope. In 2011, pheromone traps were placed in greenhouses at several locations (Banja Luka, Prijedor, Novi Grad, Kozarska Dubica, Ljubinje and Trebinje) at the beginning of June, and in open fields in Bijeljina and Trebinje at the beginning of September. Examination of the traps was carried out at intervals of 15 days. A sample of 100 leaves, taken from 20 randomly selected plants, was examined in order to evaluate the intensity of the attack. The first adults were caught in greenhouses in Ljubinje and Trebinje on 18 June 2011; in open field crops in Bijeljina on 9 September 2011 and in Banja Luka on 5 October 2011. Adults were not captured in Prijedor, Novi Grad or Kozarska Dubica, and no mined leaves were observed. The intensity of attack was evaluated on the basis of active infestation (percentage of leaves with active mines compared with all mined leaves). The strongest intensity of active infestation was recorded in the open field crops in Trebinje, where 19% of leaves with active mines were found.     

Abamectin resistance and synergism in Brazilian populations of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)

Failures in the control of the tomato leafminer Tuta absoluta (Meyrick) by means of abamectin in Brazil, and a recent report of abamectin resistance in Brazilian populations of this pest species, led to the investigation of the possible involvement of detoxification enzymes using insecticide synergists. Resistance to abamectin was observed in all populations when compared with the standard susceptible population, with resistance ratios ranging from 5.2- to 9.4-fold. Piperonyl butoxide was the most efficient synergist with abamectin synergism ratios ranging from 3.0- to 5.3-fold and providing significant resistance suppression, but complete suppression of abamectin resistance was only obtained in one population of T. absoluta . Triphenylphosphate was an abamectin synergist which was not as efficient as piperonyl butoxide, but it provided complete suppression of abamectin resistance in four of the six resistant populations studied, suggesting a major involvement of esterases as an abamectin resistance mechanism in these populations. The importance of cytochrome P450, inhibited by piperonyl butoxide, seems secondary to esterases. Diethyl maleate also synergized abamectin in nearly all populations, but provided only partial suppression of abamectin resistance in the leafminer populations studied. Therefore, glutathione-S-transferases seem to be of minor importance as an abamectin resistance mechanism in Brazilian populations of T. absoluta .     

First record of tomato leafminer Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) in Kyrgyzstan

This short note reports the first record of the tomato leaf miner Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) in Kyrgyzstan. This pest was found in February 2017 in greenhouses producing tomatoes, located 15 km from Bishkek. Identification of the pest was carried out in the Plant Protection Department, Çukurova University, Turkey based on the morphology of adults and larvae and the male genitalia. According to initial surveys this pest could be a major threat to tomato production in Kyrgyzstan.     

Response of the tomato miner Tuta absoluta (Lepidoptera: Gelechiidae) to thirteen insecticides in semi‐natural conditions in Tunisia

Experiments on larvicide and ovicide activity of 13 insecticides in semi‐natural conditions showed a medium to low efficacy of bio‐insecticides on all instars of Tuta absoluta (Meyrick) except for Bacillus thuringiensis Berliner var. kurstaki which was distinguished by an average mortality of 72.5%. Spinosad and Spinetoram based insecticides showed high efficiency in controlling all instars of larvae with respectively an average mortality of 66.5% and 85.6%. However, this study revealed a unique ovicide effect of azadirachtin‐neem oil based insecticide with 43.8% egg mortality.     

Tuta absoluta (Lepidoptera: Gelechiidae) invasion in Nigeria: first report of its distribution

Journal of Plant Diseases and Protection - The South America tomato pinworm Tuta absoluta is a serious invasive species in Nigeria. Its impacts on crop production are well understood, but its...     

Life-table analyses for the tomato leaf miner,Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae): effects of plant genotype

BACKGROUND

Host plant resistance plays an important role in integrated pest management programs. Crop resistance assessments commonly focus on only a single dependent variable, such as larval survival/plant damage, which limits the ability to appreciate the impact of host plants on pest populations in the full sense. Therefore, we performed life-table analyses for tomato leaf miner Tuta absoluta, on 19 Solanum lycopersicum genotypes and a wild Solanum habrochaites accession. These analyses assess the ability of the pest to attain a high population density on different tomato genotypes. Based on the resulting ranking of tomato resistance at the vegetative stage (45-day-old plants), we tested the resistance of six selected genotypes at the reproductive stage (4-month-old plants).

RESULTS

T. absoluta performance was significantly inferior on vegetative-stage S. habrochaites plants (LA 1777); time taken for the first instars to mine the leaves (5 ± 0.14 days), development time of early- and late-stage larvae (8.8 ± 0.2 and 4.2 ± 0.2 days, respectively), pupal period (11.2 ± 0.58 days), and total developmental time (29.4 ± 0.83 days) were significantly longer, fecundity was significantly lower (18.66 ± 7.24 days), and the highest total mortality (63.33%) also recorded compared with other genotypes, resulting in the lowest net reproductive rate (R₀) (11.20 ± 2.51). For the six selected genotypes, the ranking of plant resistance did not change between plants at the vegetative and reproductive stages.

CONCLUSION

This study suggested that of 20 screened tomato genotypes, LA 1777 and EC-620343 are the least suitable hosts for T. absoluta to establish fast-growing populations, and thus can be employed in integrated T. absoluta management. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Studies on the parasitoids of Gelechia senticetella (Stgr.) (Lepidoptera: Gelechiidae) in Bulgaria

The parasitoids of Gelechia senticetella (Stgr.) (Lepid.: Gelechiidae), a pest of Juniperus excelsa M.B., were studied in the Tissata reserve in Bulgaria. They were reared in laboratory conditions from pest larvae and pupae collected in 1991, 1992 and 2000. As a result of this study, 16 species of parasitoids of G. senticetella were recorded: Habrobracon stabilis Wesm., Hormius moniliatus (Nees), Phanerotoma tritoma Marsh. (Hym.: Braconidae), Diadegma consumptor (Grav.), Liotryphon cydiae (Perk.), Scambus pomorum (Ratz.), Scambus foliae (Cush.), Pimpla turionellae (L.), Eudelus simillimus (Tasch.), Mesochorus sp. (Hym.: Ichneumonidae), Sympiesis acalle Walk., Aprostocetus sp. (Hym.: Eulophidae), Eupelmus urozonus Dalm. (Hym.: Eupelmidae), Copidosoma thompsoni Merc. (Hym.: Encyrtidae), Calliprymna bisetosa Grah., and Mesopolobus sp. (Hym.: Pteromalidae). H. stabilis and P. tritoma were discovered as new species for the fauna of Bulgaria. Three species (E. simillimus, Mesochorus sp. and Aprostocetus sp.) are hyperparasitoids, and the remaining species are primary parasitoids. Most of the parasitoid species attack the larvae of G. senticetella and kill the hosts before pupation. In the studied parasitoid complex, D. consumptor and H. moniliatus were the dominant species. In 1991, the level of total parasitism of the host in the Tissata reserve was 24.3%, in 1992 – 57.9% and in 2000 – 12.7%. D. consumptor was the most important parasitoid destroying 26.6% of the pest larvae in 1992.     

Analysis of insecticide-resistant Myzus persicae (Sulzer) populations collected in Italian peach orchards

Several populations of the green peach aphid, Myzus persicae (Sulzer), were collected in the most important Italian peach-growing areas. In these populations, collected as primary colonies or as secondary ones, total esterase content and acetylcholinesterase sensitivity towards pirimicarb was assessed using biochemical assays. Most of the individuals analysed generally exhibited an elevated esterase content, and in some cases acetylcholinesterase insensitivity. The implications of resistance levels and distribution on M persicae control strategies are discussed.     

Susceptibility of tomato borer,Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) populations from Turkey to 7 different insecticides in laboratory bioassay

The tomato borer, Tuta absoluta (Meyrick), was first recorded in Turkey in August 2009 and rapidly became a serious pest in the Mediterranean and Aegean coastal regions in field and greenhouse grown tomatoes. Currently, insecticides are considered one of the major tools for the management of T. absoluta in Turkey. This study, investigated the efficacy of 7 different insecticides, against T. absoluta in laboratory bioassays. To determine the lethal concentration (LC) values and feeding activity of the larvae, tomato leaf parts mined by 1–3 day old L1 larvae were dipped into different insecticide concentrations. Mortality was recorded 5 days after insecticide treatments. Spinosad, chlorantraniliprole + abamectin or indoxacarb treatment resulted in 100% mortality with minimal or no feeding in all populations at their recommended doses of 120, 50.4 and 60 mg a.s. L^?1, respectively. In general, the LC₉₉ values of populations for these insecticides were similar and also lower than that of the recommended field doses. The effect of pyridalyl was low, resulting in low mortality with serious feeding damage at the dose of 125 mg a.s. L^?1. The efficacies of abamectin, metaflumizone and azadirachtin were found to be moderate to low at the recommended doses (4.5, 240 and 50 mg a.s. L^?1, respectively). However, these insecticides may affect pupation and adult emergence rates hence further studies are recommended to investigate these insecticides.     

Compatibility of insecticides and Elachertus inunctus Nees (Hymenoptera: Eulophidae) for controlling Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) in greenhouse condition

Journal of Plant Diseases and Protection - South American Tomato Pinworm (SATP), Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is one of the most devastating pests in tomato greenhouses....     

Phenology, damage and parasitoids of the apple leaf cutter Coenorhinus pauxillus (Germ.) (Col.: Attelabidae)

An outbreak on apple permitted a closer look at Coenorhinus pauxillus (Germar) (Col.: Attelabidae). The adult weevils emerge from mid-March onwards and attack the first unfolding leaves. Infested leaves drop when the larvae are in the 1^st or 2^nd instar, and it takes a further 4 weeks before the larvae are ready to pupate. Rearing of field-collected eggs and larvae is described. Leaf decomposition is an essential condition for pupation, as the fully-grown larvae do not leave their mine actively. Part of the population pupates more or less immediately and produces adult weevils in autumn. However, up to 70% of the weevils remain in prolonged diapause; their pupation does not take place before the summer of the following year. Damage by the weevil involves not only the loss of leaves of flower clusters and shoots, but also feeding damage to young fruits. Two parasitoids were found. Observations indicate that 3–4 subsequently more abundant generations of Anaphes brachygaster Debauche (Hym.: Mymaridae) develop in eggs of C. pauxillus. Probles brevicornisHorstmann (Hym.: Ichneumonidae, Tersilochinae) emerges in May and oviposits in young weevil larvae on the tree. The parasitoid does not develop into a pupa until its host starts pupating. The outbreak of apple leaf cutter did not decline over three years, but did not spread into adjacent plantings.