Invasive pests are considered a major threat to biodiversity, conservation and agriculture. The Italian peninsula is a major site of intensive commercial exchange and transport of plants and goods, ...being consequently one of the European countries most invaded by alien insects. Hemiptera Coccomorpha are the largest group of non-native species recorded in Europe. For example, in the last 70 years more than 50 scale insect species have been accidentally introduced into Italy, 50% of which are now well established. This study was conducted to investigate the biology and the damage of the non-native pine tortoise scale Toumeyella parvicornis Cockerell (Hemiptera: Coccidae) accidentally introduced a few years ago into southern Italy. T. parvicornis is multivoltine in the invaded territories, being able to complete at least three generations per year, overwintering in the adult female stage. Oviposition periods during 2015-2017 surveys occurred from late April to end of May, from July to first half of August, and from mid-September to November. Fecundity was positively correlated to body size of gravid females and varied among the generations. Investigations on natural control by autochthonous species showed a seasonal activity of Metaphycus flavus (Hymenoptera: Encyrtidae), parasitizing mainly immature male individuals. The morpho-molecular approach confirms the hypothesis of an ongoing shift of parasitoid populations from other indigenous soft scales to the invasive one. Unfortunately, the low level of natural control was ineffective in hampering the spread of T. parvicornis, and preventing the dieback of local pine species, Pinus pinea, as observed in all invaded areas.
Leafminers and potency of their parasitoids at vegetable crops in Palu Valley, Central Sulawesi. Leafminer is an exotic pest and becomes a new important pest species of onion and other vegetable ...crops in Central Sulawesi. The study aimed to survey the leafminer species and its infestation level at several vegetable crops as well as the potency of their parasitoids as biocontrol agents. Therefore, several crops (onions, tomato, cabbage, string bean, lemon basil, amaranth) were observed to identify the leafminer species and their associated parasitoids. Several leaves of all crops infested by leafminers were collected for rearing the leafminers and their parasitoids in laboratory. The study recorded three species of leafminers:Liriomyza chinensis, L. sativae, and L. huidobrensis and five species of parasitoids: Hemiptarsenus varicornis, Chrysocharis pentheus, Sympiesis sp., Gronotoma micromorpha, and Opius sp. While Liriomyza chinensis was only recorded from onion crops (monophagus), other species were poliphagus. An average infestation level among leafminer species varied, i.e. 21% -51% while parasitism ranged were 13%-40 %. The most abundant parasitoid recorded from all observed crops was H. varicornis.The results suggest that parasitoids, mainly H. varicornis have a high potential to control leafminers in the vegetable crops in Palu Valley.
The use of synthetic acaricides is currently the main method to control ticks. However, the indiscriminate use of these chemicals can lead to the selection of resistant individuals and in the ...accumulation of chemical residues in the environment, contaminating the soil and water streams, consequently affecting the flora, fauna, and the human beings as well. In this sense, the objective of this study was to investigate the acaricidal effect of crude ethanolic extract of Acmella oleracea (L.) R.K. Jansen aerials parts at different concentrations on fed males and semi-engorged females of A. cajennense s.s. An in vitro bioassay (Adult Immersion Test) was carried out to determine the lethal concentration 50 (LC
) of ethanolic extract, calculated by Probit analysis. The results showed that the fed males were sensitive to all the concentrations of A. oleracea ethanolic extract, and mortality rate progressively increased (15-65%) in higher ethanolic extract concentrations. However, semi-engorged females were not sensitive to all the concentrations used here. In the highest concentration (100mg/mL), a mortality rate of 100% was observed after 72h of exposure, indicating that the acaricidal effect would probably be dose-dependent. The LC
values obtained for the fed A. cajennense s.s males and semi-engorged females were 29.4534mg/mL (limits: 24.4467-41.3847mg/mL) and LC
=17.6335mg/mL (limits: 5.2506-23.5335mg/mL), respectively.
Diversity, permanence, and activity of terrestrial arthropods were investigated in four areas of different land use in the lowlands of the Pacific coast of Colombia with the aim to identify potential ...predator species for the palm root borer, Sagalassa valida. Ten pitfall traps were established along a 100 m transect in four areas: a secondary forest, a 20 year.-old peach palm plantation, and two hybrid oil palm plantations of three and seven years of age, respectively. Twenty-two collections were made covering a whole year. All ants were identified to species or morphospecies level, the other arthropods to order or where possible to family level. In total, 50,603 arthropods were captured, the most abundant were ants (37.0 %), followed by Collembola (35.4 %), Acari (10.6 %), Coleoptera (7.0 %) and Diptera, Hemiptera and Araneae in almost equal numbers (around 2.5 %). Orthoptera (92 % Gryllidae) were present in all collections, always at low numbers. The highest number of ants were recorded in the oil palm transects; Diptera, Hemiptera and Orthoptera were more numerous in the secondary forest, Acari, Araneae and Collembola in the palm transects. Ectatomma ruidum was by far the dominant ant species (84.9 % of all specimens) and absent from only 20 of the 880 captures. The second most frequent ant genus were army ants with two species, Labidus praedator and L. coecus. Rainfall, even area-wide flooding, and temperature did not explain variability in captures of any taxonomic group satisfactorily. We conclude that E. ruidum might be the predator to provide control of the root borer and recommend further studies on its efficiency.
From 2006 to 2008, we studied the natural mortality of olive fly, Bactrocera oleae (Rossi), eggs and larvae as collected in fruit on the tree, in two to five 'traditional' olive groves of ...Trás-os-Montes (north-eastern Portugal), per year. We also studied the fate of 2044 puparia that were buried in the soil from November to May for two seasons, by using exclusion cages to estimate predation. Mortality of eggs inside the fruit was estimated as between 5.4±2.4 and 16.6±6.1%, and as 10.7±2.1 and 100.0% for young larvae. Similarly, the estimated mortality of mature larvae was between 0 and 66.7±33.3%. The highest mortality levels for young larvae could reach 100% during August, and 47.4% during the first fortnight of December, coincident with high temperatures in summer or low temperatures at the end of autumn and early winter. Mortality (winter disappearance) of puparia was estimated at up to 98.5% of the population. Predation of eggs was low, at 0.6±0.3 to 6.3±4.0% in 2006, 0 to 4.1±1.1% in 2007, and 0 to 3.6±3.6% in 2008. Parasitism was insignificant during the study, and only one parasitoid was identified, the eulophid Pnigalio agraules (Walker). We also surveyed entomopathogenic fungi associated with the insect in 12 olive groves, and evaluated three of the latter against larvae, puparia, and adult B. oleae in the laboratory. Of the 15 fungal species identified from immature stages, three were considered to be entomopathogenic (i.e. Cordyceps bassiana, Penicillium corylophilum and Mucor hiemalis). We observed up to 20.0±3.2% and 94.0±2.5% mortality of larvae and puparia, respectively when treated with P. corylophilum and up to 32.5±11.1% of adults when treated with M. hiemalis.
Soybean Glycine max (L.), one of the most important crops in Argentina, is commonly infected by Colletotrichum truncatum, the causal agent of anthracnose. Tagetes filifolia essential oil (EO) is ...presented as a natural approach to minimize the dose of chemical fungicides applied to the crop. The fungus Trichoderma harzianum is used as a biocontrol agent because of its ability to produce secondary metabolites that destroy cell walls of phytopathogenic fungi. However, its performance can be affected when it is exposed to chemical fungicides. The objective of this work was to evaluate the antifungal activity of T. filifolia EO both individually and combined with chemical fungicides against C. truncatum, and its effect on T. harzianum. Fungi were isolated from soybean crops. The following pesticides were assessed: carbendazim (F1), difenoconazole (F2) and trifloxystrobin + cyproconazole (F3). The EO was obtained from native plants and its chemical composition was analyzed by gas chromatography–mass spectrometry (GC–MS). The minimum fungicide concentration (MFC) was determined for each compound. Fungicides were combined with the EO to look for combinations that allowed a reduction of pesticide doses. Among fungicides, F1 showed the strongest antifungal activity against C. truncatum (MFC = 0.25 μl ⋅ l–1) and T. harzianum (MFC = 1.5 μl ⋅ l–1). The sensitivity of both fungi to the EO was lower than to fungicides. The EO presented MFCs of 6,000 and 9,000 μl ⋅ l–1 against C. truncatum and T. harzianum. The EO and F1 affected the growth of T. harzianum at concentrations that controlled C. truncatum (31 and 10%). Eight combinations of fungicides and the EO allowed fungicide concentration reductions of up to 80%, although the growth of the biocontrol strain was also affected. The results demonstrated that T. filifolia EO can be used to control anthracnose and reduce doses of chemical fungicides applied to soybean crops. Its effect on T. harzianum should be considered in the design of integrated pest management strategies.
El minador de la hoja del café, Leucoptera coffeella, es una de las principales plagas del cultivo del café (Coffea arabica) en la región neotropical, ocasionando pérdidas en rendimiento hasta del ...80%, en países como Brasil. En Colombia ha sido poco estudiado, debido a que los ataques han sido esporádicos. Esta investigación exploratoria fue conducida con el propósito de realizar un diagnóstico del minador y sus parasitoides en el departamento de Antioquia, donde se evaluó el porcentaje de infestación de la plaga y el parasitismo natural, a través de un muestreo bietápico en más de 1.100 lotes cafeteros entre 2 y 5 años de edad. Se evaluaron 60 árboles por lote mediante un muestreo sistemático, durante cuatro momentos entre los años 2013 y 2014. Los resultados mostraron promedios de infestación del minador inferiores al 2% y promedios de parasitismo que oscilaron entre 58 y 89 %. Emergieron en total, 787 parasitoides del orden Hymenoptera, familia Eulophidae, distribuidos en dos subfamilias: Eulophinae y Entodininae. Se identificaron siete especies: Closterocerus coffeellae, Closterocerus lividus, Zagrammosoma multilineatum, Pnigalio sarasolai, Horismenus sp., Horismenus n. sp., y Apleurotropis n. sp., estas dos últimás nuevas especies para Colombia, y quizás para la ciencia. El controlador natural más abundante fue C. coffeellae. Se recomienda el manejo de esta plaga, a partir de una estrategia de control biológico por conservación. Palabras clave: Coffea arabica. Enemigos naturales. Minador de la hoja del café. Control natural. Control biológico por conservación. Coffee Leaf Miner, Leucoptera coffeella is one of the main insect coffee pests in the Neotropics, causing yield decreases up to 80%, in countries such as Brazil. In Colombia, this insect pest has been poorly studied, since the damage it causes has been sporadic. This exploratory investigation was carried out in order to diagnose the damage caused by the coffee leaf miner and its parasitoids in the department of Antioquia. Pest infestation levels were evaluated as to incidences of natural parasitism, identifying the species of the parasitoids, through a bietapic sampling performed in more than 1,100 coffee crops between the ages of 2 and 5 years. Sixty (60) coffee trees per crop were evaluated four times through systematic sampling between 2013 and 2014. The results indicated an average of leaf miner infestation level under 2%, and parasitism levels between 58 and 89 %. In total, 787 parasitoid individuals emerged, all belonged to the Order Hymenoptera, family Eulophidae, comprising two subfamilies: Eulophinae and Entodininae. Seven parasitoid species were identified: Closterocerus coffeellae, Closterocerus lividus, Zagrammosoma multilineatum, Pnigalio sarasolai, Horismenus sp., Horismenus n. sp., and Apleurotropis n. sp. These last two new species for Colombia, and perhaps for science. The most abundant natural enemy of coffee leaf miner was the species C. coffeellae. The management of this insect pest by means of a conservation biological control strategy is recommended. Key words: Coffea arabica. Natural enemies. Coffee leaf miner. Natural control. Conservation biological control.
Background: Chaetogaster limnaei is an annelid symbiotically associated with lymnaeid snails as Galba truncatula. This association is considered a preventive mechanism against trematode miracidia ...infection, including Fasciola hepatica. The objective of this study was to determine the effectiveness of Chaetogaster limnaei as a natural controller of Fasciola hepatica in laboratory conditions. Procedures: Fasciola hepatica miracidia were inoculated in parallel into snails carrying Chaetogaster limnaei and snails without the annelid. The degree of infection was measured after 40 days of exposure. Furthermore, the number of annelids per snail was quantified, as well as the ability of Chaetogaster limnaei to devour miracidia at different times of exposure. Results: An effective 70% natural control of Fasciola hepatica in Galba truncatula was observed. The carrying capacity of the snail was established to be of 10.6 ± 1 annelids. Chaetogaster limnaei is a predator of Fasciola hepatica devouring an average of 3.79 ± 0.21 miracidia. The results of these experiments have a potential value as a control measure against fascioliasis in the environment.
ABSTRACT This paper summarizes the natural enemies of major sugarcane pests and their roles in natural control in sugarcane growing regions in Yunnan. In general, these natural enemies can be divided ...into two groups: parasites and predators. The dominant species include Apanteles flavipes (Cameron), Sturmiopsis inferens Townsend and Trichogramma sp., which parasitize the sugarcane borer; Synonycha grandis (Thunberg), Lemnia biplagiata (Swartz), Cheilomenes sexmaculata (Fabricius) and Thiallela sp., which prey on Ceratovacuna lanigera Zehntner; and Euborellia pallipes Shiraki, Orius (Heterorius) minutus (Linnaeus) and Scymnus (Neopullus) hoffmanni Weise which preys on Saccharicoccus sacchari (Cocherell), Baliothrips serratus Kobus and Trochorhopalus humeralis Chevrolat. Protecting these natural enemies will encourage natural control of pest species while protecting the environment and maintaining ecological balance. Moreover, through enhanced comprehensive pest control, sustainable development of the sugar industry will be promoted.
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