Microbial control of diamondback moth, Plutella xylostella L. (Lepidoptera:Yponomeutidae) using bacteria (Xenorhabdus nematophila) and its metabolites from the entomopathogenic nematode Steinernema carpocapsae

Cells and cell-free solutions of the culture filtrate of the bacterial symbiont, Xenorhabdus nematophila taken from the entomopathogenic nematode Steinernema carpocapsae in aqueous broth suspensions were lethal to larvae of the diamondback moth Plutella xylostella. Their application on leaves of Chinese cabbage indicated that the cells can penetrate into the insects in the absence of the nematode vector. Cell-free solutions containing metabolites were also proved as effective as bacterial cells suspension. The application of aqueous suspensions of cells of X. nematophila or solutions containing its toxic metabolites to the leaves represents a possible new strategy for controlling insect pests on foliage.

Conserving marginal populations of the foodplant (Impatiens noli-tangere) of an endangered moth (Eustroma reticulatum) in a changing climate

Impatiens noli-tangere is scarce in the UK and probably only native to the Lake District and Wales. It is the sole food plant for the endangered moth Eustroma reticulattum. Significant annual fluctuations in the size of I. noli-tangere populations endanger the continued presence of E. reticulatum in the UK. In this study, variation in population size was monitored across native populations of L noli-tangere in the English Lake District and Wales. In 1998, there was a crash in the population size of all metapopulations in the Lake District but not of those found in Wales. A molecular survey of the genetic affinities of samples in 1999 from both regions and a reference population from Switzerland was performed using AFLP and ISSR analyses. The consensus UPGMA dendrogram and a PCO scatter plot revealed clear differentiation between the populations of L noli-tangere in Wales and those in the Lake District. Most of the genetic variation in the UK (H-T= 0.064) was partitioned between (G(ST) = 0.455) rather than within (H-S = 0.034) regions, inferring little gene flow occurs between regions. There was similar bias towards differentiation between metapopulations in Wales, again consistent with low levels of interpopulation gene flow. This contrasts with far lower levels of differentiation in the Lake District which suggests modest rates of gene flow may occur between populations. It is concluded that in the event of local extinction of sites or populations, reintroductions should be restricted to samples collected from the same region. We then surveyed climatic variables to identify those most likely to cause local extinctions. Climatic correlates of population size were sought from two Lake District metapopulations situated close to a meteorological station. A combination of three climatic variables common to both sites explained 81-84% of the variation in plant number between 1990 and 2001. Projected trends for these climatic variables were used in a Monte Carlo simulation which suggested an increased risk of I. noli-tangere population crashes by 2050 at Coniston Water. but not at Derwentwater. Implications of these findings for practical conservation strategies are explored. (C) 2003 Elsevier Ltd. All rights reserved.

The influence of lodgepole pine (Pinus contorta) provenance on the development and survival of larvae of the pine beauty moth Panolis flammea (Lepidoptera: Noctuidae)

Larvae of the pine beauty moth Panolis flammae (Denis & Schiffermuller) were reared in sleeve cages on five different seed origins (provenances) of pole stage Pinus contorta in the field in each of four years from 1985 to 1988. Survival varied significantly between the years. In those years when survival was high, significant differences between tree provenance were not found. However, between provenance significant differences were found in larval weight and stage of development. In the years when survival was low, the results seen in good years were reversed. Significant differences attributable to provenance were found but these were not reflected in significant differences between larval weight or development. In addition, there was a significant correlation between the proportion surviving and larval weight, which was not the case in those years where larval survival was high. The results are discussed in light of the pest status of P, flammea in Britain and in view of current silvicultural policies. The use of trees resistant to insect attack as part of an integrated pest management programme is highlighted and the need to coordinate laboratory and field studies so as to control for environmental variation discussed.

Are differences in life history parameters of the pine beauty moth Panolis flammea modified by host plant quality or gender?

Pine beauty moth (Panolis flammea D&S, Lepidoptera: Noctuidae) were reared individually from egg hatch to pupation on one of three host plants, Pinus sylvestris (native host plant), Pinus contorta (Central Interior seed origin - good quality introduced host) and P. contorta (Alaskan seed origin - poor quality introduced host). After emerging from the pupae the adult moths were confined to a Skeena River seed origin of P. contorta. Female pupal weight and adult life span were significantly higher on P. sylvestris than on the two lodgepole pine seed origins. Development time was, however, not significantly different between treatments, but larval mean relative growth rate was found to be negatively correlated with birth weight and positively correlated with pupal weight. The time to emerge from the pupa was also not significantly different between treatments. However, there were marked differences between the genders. Male moths lost a significantly greater proportion of their weight over the pupal stage but lived significantly longer as adults than the females. Female moths emerged from the pupal stage significantly sooner than male moths. There was no apparent advantage of lai-ge birth size when looked at in terms of subsequent performance. These results are discussed in light of current life history theory.

Mechanisms of partial plant resistance to diamondback moth (Plutella xylostella) in brassicas

Artificial diet studies were used to differentiate among physical and chemical mechanisms affecting the suitability to diamondback moth (Plutella xylostella L.), of 16 food substrates obtained by growing four different brassicas in the glasshouse or field and measuring the pest's performance on either leaf discs or a diet incorporating leaf powders. Leaves of Chinese cabbage and the cabbage cultivar 'Minicole' were, respectively, the most and least suitable leaves for the insect, but this ranking was reversed on artificial diet. Leaves of glasshouse-grown plants were more suitable than those of plants grown in the fields. Differences in the suitability of leaves to diamondback moth appeared to be largely determined by leaf toughness and surface wax load. Concentrations of individual glucosinolates in the brassicas probably acted as phagostimulants, so increasing their intrinsic susceptibility to diamondback moth, but the effect of the physical factors appeared more important.

Observations on the flight paths of the day-flying moth Virbia lamae during periods of mate location: do males have a strategy for contacting the pheromone plume?

1. To maximize the probability of rapid contact with a female’s pheromone plume, the trajectories of male foraging flights might be expected to be directed with respect to wind flow and also to be energetically efficient. 2. Flights directed either upwind, downwind, or crosswind have been proposed as optimal strategies for rapid and/or energetically efficient plume contact. Other possible strategies are random and Lévy walks, which have trajectories and turn frequencies that are not dictated by the direction of wind flow. 3. The planar flight paths of males of the day-active moth Virbia lamae were recorded during the customary time of its sexual activity. 4. We found no directional preference in these foraging flights with respect to the direction of contemporaneous wind flow, but, because crosswind encompasses twice the possible orientations of either upwind or downwind, a random orientation is in effect a de facto crosswind strategy. 5. A crosswind preference should be favoured when the plume extends farther downwind than crosswind, and this strategy is realized by V. lamae males by a random orientation of their trajectories with respect to current wind direction

Development and silk production by silkworm larvae after topical application of methoprene

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Diamondback moth oviposition nonpreference in cauliflower genotypes

The Diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is one of the main plague-insect specie of Brassicaceae plants in Brazil and all over the world. The resistant genotypes use to its control is a promising alternative. This work aimed evaluates the eggs distribution along the plant, the adults' density per plant, and determine the cauliflower genotypes effect in the P. xylostella oviposition. The experiment was carried out at FCAV/UNESP-Jaboticabal Campus Phytossanity Department (Departamento de Fitossanidade). It was evaluated the eggs distribution, the P. xylostella adults density effect using Sharon hybrid, and tests with or without choose choice to determine the P. xylostella nonpreference in the Teresopolis Gigante, Verona, Barcelona, Sharon, Silver Streak, and Piracicaba Precoce genotypes. It is possible conclude that P. xylostella has higher willingness to oviposits in the stem than in the basal leaves. The three couple density of P. xylostella per plant is the best to discriminate cauliflower genotypes regarding the resistance grade to nonpreference choose choice to oviposition. During the P. xylostella oviposition preference tests with choose choice, the genotypes Sharon, Piracicaba Precoce, Barcelona, Verona e Teresopolis Gigante are less desirable to oviposition; while during the no choose choice tests the genotypes did not differ among them.

The effect of Beauveria bassiana on Brazilian poplar moth Condylorrhiza vestigialis (Lepidoptera: Crambidae)

The Brazilian poplar moth is the most important pest of poplar plantations in Brazil. This research evaluated the effect of Beauveria bassiana Bals. (Vuill.) on the mortality and development of Condylorrhiza vestigialis Guen. (Lepidoptera: Crambidae). The aim was to develop alternative methods for management of this pest. The pathogens were sprayed on poplar leaves and .consequently, the pathogens reached the caterpillars. Bacillus thuringiensis var. kurstaki Berliner was sprayed as the standard treatment. The spray for the control was distilled water. Both pathogens B. bassiana and B. thuringiensis affected insect development with increase mortality at each stage of the insect cycle, reaching a satisfactory control level. Microbial control of Brazilian poplar moth with B. bassiana is promising. Tests with other strains and species of pathogens, mainly under field conditions, were also encouraging. This is the first report about the action of B. bassiana against C. vestigialis.

Classification of crucifer cultivars based on the life-history of diamondback moth (Plutella xylostella)

We compared different cultivars and hybrids of crucifers in relation to development and life-history of diamondback moth (Plutella xylostella) to classify the plants according to their resistance to the pest. The plants used were Manteiga da Geórgia kale, Bola de Neve cauliflower, Ramoso Piracicaba Precoce broccoli, Chato-de-quintal cabbage, and the hybrid cabbages Midori, TPC668, TPC308, and TPC681. We evaluated performance daily until the pupal stage. Pupae were assessed individually to determine the pupal weight, performance, and pupal period. We determined the sex ratio, fecundity, fertility, and longevity of the emerged adults and calculated their reproductive potential. Cabbage hybrids TPC668, TPC308, and TPC681 do not support the development and reproduction of the diamondback moth. These hybrids show a level of resistance that is similar to that found the commercially available hybrid Midori and cultivar Chato de Quintal, which are known to be resistant to the diamondback moth. This finding implies that the capitata (cabbage) cultivars are the most suitable for planting because they are more resistant to pest than the cultivar's moth, acephala (kale). © 2013 Copyright Taylor and Francis Group, LLC.

Análises técnica e energética da secagem combinada no processamento de casulo do bicho-da-seda de Bombyx Mori L

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Impact of different silkworm dietary supplements on its silk performance

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Stay out (almost) all night: contrasting responses in flight activity among tropical moth assemblages

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Revision of the Neotropical moth genera Mallodeta Butler and Erruca Walker, revalidated (Noctuidae, Arctiinae, Arctiini, Euchromiina)

Mallodeta Butler and Erruca Walker, revalidated, are redescribed and revised. Mallodeta henceforth includes only its type-species, Glaucopis (Lycorea) clavata Walker, and Erruca is resurrected with seven species: E. deyrolii Walker (type-species), E. consors (Walker), new combination, E. erythrarchos (Walker), new combination, E. cardinalis (Hampson), new combination, E. hanga (Herrich-Schaffer), new combination, E. cruenta (Perty), new combination and E. sanguipuncta (Druce), new combination. Six new synonyms are established, four specific and two generic (junior synonyms in parentheses): Zygaena capistrata Fabricius (=Mallodeta cubana Gaede), Glaucopis (Lycorea) clavata Walker (=M. simplex Rothschild), Erruca deyrolii Walker (=Laemocharis aecyra Herrich-Schaffer and Glaucopis (Hyda) sortita Walker), and Erruca Walker (=Aristodaema Wallengren and Rezia Kirby). Lectotypes are designated to the following species: Erruca deyrolii Walker, Laemocharis deyrollei Herrich-Schaffer, Laemocharis hanga Herrich-Schaffer, Laemocharis aecyra Herrich-Schaffer, Laemocharis norma Herrich-Schaffer, Cosmosoma cardinalis Hampson and Mallodeta sanguipuncta Druce. Illustrations of adults and male and female genitalia of Mallodeta and Erruca are provided, as well as a key to the species of the latter.

On the inheritance and mechanism of baculovirus resistance of the codling moth, Cydia pomonella (L.)

Das Cydia pomonella Granulovirus (CpGV, Baculoviridae) wird seit Ende der 1980er Jahre als hoch-selektives und effizientes biologisches Bekämpfungsmittel zur Kontrolle des Apfelwicklers im Obstanbau eingesetzt. Seit 2004 wurden in Europa verschiedene Apfelwicklerpopulationen beobachtet die resistent gegenüber dem hauptsächlich angewendeten Isolat CpGV-M aufweisen. Die vorliegende Arbeit befasst sich mit der Untersuchung der Vererbung und des Mechanismus der CpGV Resistenz. Einzelpaarkreuzungen zwischen einem empfindlichen Laborstamm (CpS) und einem homogen resistenten Stamm (CpRR1) zeigten, dass die Resistenz durch ein einziges dominantes Gen, das auf dem Z-Chromosom lokalisiert ist, vererbt wird. Massernkreuzungen zwischen CpS und einer heterogen resistenten Feldpopulation (CpR) deuteten zunächst auf einen unvollständig dominanten autosomalen Erbgang hin. Einzelpaarkreuzungen zwischen CpS und CpR bewiesen jedoch, dass die Resistenz in CpR ebenfalls monogen dominant und geschlechtsgebunden auf dem Z-Chromosom vererbt wird. Diese Arbeit diskutiert zudem die Vor- und Nachteile von Einzelpaarkreuzungen gegenüber Massernkreuzungen bei der Untersuchung von Vererbungsmechanismen. Die Wirksamkeit eines neuen CpGV Isolates aus dem Iran (CpGV-I12) gegenüber CpRR1 Larven, wurde in Bioassays getestet. Die Ergebnisse zeigen, dass CpGV-I12 die Resistenz in allen Larvenstadien von CpRR1 brechen kann und fast so gut wirkt wie CpGV-M gegenüber CpS Larven. Daher ist CpGV-I12 für die Kontrolle des Apfelwicklers in Anlagen wo die Resistenz aufgetreten ist geeignet. Um den der CpGV Resistenz zugrunde liegenden Mechanismus zu untersuchen, wurden vier verschiedene Experimente durchgeführt: 1) die peritrophische Membran degradiert indem ein optischer Aufheller dem virus-enthaltenden Futtermedium beigefügt wurde. Das Entfernen dieser mechanischen Schutzbarriere, die den Mitteldarm auskleidet, führte allerdings nicht zu einer Reduzierung der Resistenz in CpR Larven. Demnach ist die peritrophische Membran nicht am Resistenzmechanismus beteiligt. 2) Die Injektion von Budded Virus in das Hämocoel führte nicht zur Brechung der Resistenz. Folglich die die Resistenz nicht auf den Mitteldarm beschränkt, sondern auch in der Sekundärinfektion wirksam. 3) Die Replikation von CpGV in verschiedenen Geweben (Mitteldarm, Hämolymphe und Fettkörper) von CpS und CpRR1 wurde mittels quantitativer PCR verfolgt. In CpS Larven konnte in allen drei Gewebetypen sowohl nach oraler als auch nach intra-hämocoelarer Infektion eine Zunahme der CpGV Genome in Abhängigkeit der Zeit festgestellt werden. Dagegen konnte in den Geweben aus CpRR1 nach oraler sowie intra-hämocoelarer Infektion keine Virusreplikation detektiert werden. Dies deutet darauf hin, dass die CpGV Resistenz in allen Zelltypen präsent ist. 4) Um zu untersuchen ob ein humoraler Faktor in der Hämolymphe ursächlich an der Resistenz beteiligt ist, wurde Hämolymphe aus CpRR1 Larven in CpS Larven injiziert und diese anschließend oral mit CpGV infiziert. Es konnte jedoch keine Immunreaktion beobachtet und kein Faktor in der Hämolymphe identifiziert werden, der Resistenz induzieren könnte. Auf Grundlage dieser Ergebnisse kann festgestellt werden, dass in resistenten Apfelwicklerlarven die virale Replikation in allen Zelltypen verhindert wird, was auf eine Virus-Zell Inkompatibilität hinweist. Da in CpRR1 keine DNA Replikation beobachtet wurde, wird die CpGV Resistenz wahrscheinlich durch eine frühe Unterbindung der Virusreplikation verursacht.Das früh exprimierte Gen pe38 codiert für ein Protein, das wahrscheinlich für die Resistenzbrechung durch CpGV-I12 verantwortlich ist. Interaktionen zwischen dem Protein PE38 und Proteinen in CpRR1 wurden mit Hilfe des Yeast Two-Hybrid (Y2H) Systems untersucht. Die detektierten Interaktionen sind noch nicht durch andere Methoden bestätigt, jedoch wurden zwei mögliche Gene auf dem Z-Chromosom und eines auf Chromosom 15 gefunden, wie möglicherweise an der CpGV Resistenz beteiligt sind.