12 research outputs found
Egg parasitoids of the genus Trichogramma (Hymenoptera, Trichogrammatidae) in olive groves of the Mediterranean region
A survey of egg parasitoids of the genus Trichogramma (Hymenoptera, Trichogrammatidae) was carried out in olive groves in Portugal,
Greece, Egypt, and Tunisia during the years 2002–2004. Parasitoids were obtained either by exposing sentinel eggs (Sitotroga
cerealella Olivier or Ephestia kuehniella Zeller) on olive trees or by collecting eggs of lepidopterous olive pests. Parasitized egg samples
were reared separately in the laboratory for emergence of parasitoids. These were further reared in separate lines and processed by morphological
and molecular biology techniques for species characterization. The recorded fauna of Trichogramma parasitoids in olive
groves was species poor and consisted of species mainly known from the Mediterranean region. Trichogramma bourarachae Pintureau
and Babault was found in Tunisia and Egypt, T. cordubensis Vargas and Cabello, and T. euproctidis Girault in Egypt, Trichogramma
cacoeciae Marchal in Portugal, Greece, Egypt, Tunisia and Trichogramma nerudai Pintureau and Gerding in Portugal. Apart from that,
Trichogramma oleae Voegele´ and Pointel was collected in Tunisia. This species is probably not indigenous, but has established after several
releases of a French strain were made in recent years. For selected strains, the sequence of the internal transcribed spacer 2 (ITS-2)
region of rDNA was determined and deposited in the GenBank database. Differences in important biological attributes were found
among collected strains of T. bourarachae, suggesting the existence of biotypes. The results contribute to the limited knowledge on distribution
and biodiversity of the genus Trichogramma in the Mediterranean region. They can be helpful for the preservation and use of
indigenous Trichogramma species in biological control of lepidopterous pests in olive and other local crops
Entwicklung nachhaltiger Pflanzenschutzstrategien zur Bek_mpfung von Schadschmetterlingen im olivenanbau
Current olive growing practices range from the traditional Mediterranean olive grove to intensively managed olive plantations. Insecticides against major olive pests, like the olive moth (Prays oleae, Lep.:
Yponomeutidae) and the jasmine moth, (Palpita unionalis, Lep.: Pyralidae) are still applied frequently. The European Union-funded international research project
TRIPHELIO is aimed at the development of economically feasible and sustainable insecticide-free control methods for key Lepidopterous pests of olive. Main research activities focus on (1) the use of pheromones for mating disruption and improved monitoring of target pests, (2)
habitat management strategies to enhance the activity of natural enemies in the olive grove, and (3) the use of inundative releases of mass-reared egg parasitoids of the genus Trichogramma. Moreover, tools for successful integration of the methods developed into an integrated pest
management (IPM) strategy for olive pests were explored by optimising techniques for surveillance as well as considering potential side-effects of common pesticides
on beneficial organisms. An intense exchange of scientific information and technology between European and North African countries was undertaken to create solutions for a wide range of olive growing regions. Key results and recommendations for further essential steps towards practical implementation are presented in this
publication.Zusammenfassung Traditionelle, extensiv bearbeitete Olivenhaine, aber auch moderne Intensiv-Plantagen mit k_nstlicher Bew_sserung und hohem Einsatz von D_ngern
bzw. chemischen Pflanzenschutzmitteln kennzeichnen die derzeitigen verschiedenen Anbauformen der Olive im Mittelmeerraum. Schadlepidopteren wie die Olivenmotte (Prays oleae, Lep.: Yponomeutidae) und die
Jasminmotte (Palpita unionalis, Lep.: Pyralidae) werden durch regelm_ssigen Insektizideinsatz bek_mpft. Das von
der EU gef_rderte internationale Forschungsprojekt TRIPHELIO zielte auf die Entwicklung insektizidfreier
Alternativmethoden durch (1) die Optimierung der pheromongest _tzten _berwachung und Verwirrtechnik, (2) der Anwendung von Habitatmanagement-Strategien zur
F_rderung nat_rlicher Gegenspieler, und (3) dem Einsatz von Trichogramma-Schlupfwespen. Zus_tzlich wurden Module f_r eine optimale Anwendung biotechnischer und
biologischer Methoden bez_glich der Ph_nologie der Schadinsekten und m_glicher Nebenwirkungen von Pestiziden erarbeitet. Die intensive Kooperation zwischen
Wissenschaftlern und Praktikern aus mehreren L_ndern Europas und Nordafrikas erlaubte den Entwurf m_glicher L_sungsans_tze f_r verschiedene Anbaubedingungen und
klimatische Regionen des Mittelmeerraumes. Die wichtigsten Ergebnisse und Ausblicke f_r eine zuk_nftige praktische Umsetzung werden in dieser Ver_ffentlichung beschrieben
Prospects for sustainable control of Lepidopterous olive pests by pheromones and egg parasitoids.
Triphelio – an international research project for sustainable control of lepidopterous pests in olive groves.
The olive moth (Prays oleae, Lepidoptera: Plutellidae) is known as one of the key pests in olive
cultivation. In particular areas, also the jasmine moth (Pal pita zmionalis, Lepidoptera:
Pyralidae) can cause serious damage to both leaves and fiuits of the olive tree. Both pests are
mainly controlled by insecticide applications. In November 200 I, an international research
project was started to promote biological and biotechnical methods for the control of these
pests
Prospects to use releases of the egg parasitoid Trichogramma (Hymenoptera, Trichogrammatidae) for biological control in olive cultivation – lessons from the EU-project “Triphelio“.
Flux recovery scheme for elliptic interface problems
This paper introduces a flux recovery algorithm that ensures the continuity of the flux at the interface and improves its accuracy. At each subdomain created by an interface, the gradient is recovered using the polynomial preserving recovery method and a weight is given to each subdomain based on these recovered gradients. Then from these recovered gradients and subdomain weights, we form what we call a corrected recovered gradient that is exploited to construct the recovered flux at the interface. An error estimator that is based on the recovered flux is formulated for an adaptive refinement scheme that improves the accuracy of the flux near the interface. We present the numerical results of applying the proposed scheme to some two-dimensional experiments with different types of interfaces
Ocena właściwości przędz mieszanych wełna/poliester
Seven-hundred kilograms of subtropical Barki wool was collected to study the effect of a subjective grading system and blending with polyester on selected wool and yarn characteristics. Wool was graded subjectively into coarse, fine and raw; then each grade was blended with 0%, 15%, 25%, 35% and 45% of polyester. Staple and yarn strengths were higher in both coarse and fine grades compared with raw wool. Staple elongation of the fine grade reached 3 times that of coarse grade and twice as much as raw grade. Also, in the 100% wool blend, yarn elongation of the fine grade was twice as much as both coarse and raw grades. The fine grade had the highest yarn friction, followed by other grades. Generally, adding polyester to coarse and fine grades led to an improved yarn strength compared with the raw grade. Adding 15% polyester caused the highest improvement among other percentages. Correlations among traits were also discussed.Do badań wykorzystano 700 kg wełny. Dokonano oceny wybranych właściwości wełny i przędz mieszanych wełna/poliester. Wełna była oceniana subiektywnie na grubą, cienką i surową; następnie każdy gatunek został zmieszany z 0%, 15%, 25%, 35% i 45% poliestru. Zbadano wytrzymałość, wydłużenie i współczynnik tarcia przędz. Stwierdzono, że, dodawanie poliestru do grubych i cienkich włókien wełnianych prowadziło do polepszenia wytrzymałości przędz w porównaniu do przędz z włókien surowych. Największą poprawę właściwości spowodowało dodanie 15% poliestru. Omówiono również korelacje między cechami