GENERAL DECAY OF SOLUTION FOR COUPLED SYSTEM OF VISCOELASTIC WAVE EQUATIONS OF KIRCHHOFF TYPE WITH DENSITY IN Rn

A system of viscoelastic wave equations of Kirchhoff type is considered. For a wider class of relaxation functions, we use spaces weighted by the density function to establish a very general decay rate of the solution

Suitability of Ectomyelois ceratoniae Zeller (Lepidoptera: Pyralidae) as host for two local Trichogramma species (Hymenoptera: Trichogrammatidae) and possible implications on biological control programs

In this study, laboratory tests were conducted to evaluate the suitability of Ectomyelois ceratoniae (Zeller) eggs as host for the development of two Trichogramma species: Trichogramma cacoeciae (Marchal) and Trichogramma bourarachae (Pintureau and Babault) (Hymenoptera: Trichogrammatidae) collected in Tunisia and reared on Ephestia kuehniella Zeller eggs. We also studied effects of five different temperature regimes (15, 20, 25, 30 and 35°C) on the biological traits of these two parasitoids. Results showed that eggs of E. ceratoniae were more suitable for the development of T. bourarachae. The number of parasitized eggs (15.46±2.04) as well as the emergence rate (95.78±5.10) was significantly higher compared to T. cacoeciae. For both Trichogramma species, the highest parasitism rate was observed at 30°C. At 35°C, the mean number of parasitized eggs (32.06±13.32) and the longevity (4.03±0.56) of T. bourarachae females were significantly higher compared to T. cacoeciae. The developmental time of both Trichogramma species was shorter at higher temperatures. The emergence rates were similar and relatively high in all tested temperature ranging from 80.48% to 97.92% for T. bourarachae and from 92.03% to 99.33% for T. cacoeciae

Life History Parameters of Diachasmimorpha longicaudata on Ceratitis capitata Under Laboratory Conditions: Implications for Mass Rearing and Biological Control

The Mediterranean fruit fly, Ceratitis capitata, is considered one of the most destructive pests worldwide. The braconid Diachasmimorpha longicaudata is the most widely used parasitoid in biological control programs of tephritids. It has been mass-reared and used in augmentative releases against major fruit fly species in tropical and subtropical countries, and recently in the Mediterranean Basin. After its introduction into Spain and then Tunisia, reproductive and demographic parameters have been studied on C. capitata under laboratory conditions. These parameters were compared to those published elsewhere. The role of artificial diet for rearing the host is discussed. Our findings showed the good fitness of the parasitoids produced on C. capitata in laboratory with a generation time of 28.1 days, a reproductive rate of 39.2, an intrinsic rate of increase of 0.125, a doubling time of 5.2 days and the finite rate of increase (per day) was 1. Involvements on the biological control of the Mediterranean fruit fly in Tunisia are discussed

Integrated pest management of Tuta absoluta: practical implementations across different world regions

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has invaded most Afro-Eurasian countries and is threatening worldwide tomato production. Various strategies have been developed and implemented to manage this pest. Here, we present a timely review on the up-to-date development and practical implementation of integrated pest management (IPM) programs for tomato crops across different world regions infested by T. absoluta. While insecticide resistance is a growing concern, biological control via releasing or conserving arthropod natural enemies and sex pheromone-based biotechnical control are the most successful management practices. Agronomic control-related research is an emerging area where the soil fertilization and/or irrigation, as well as breeding of resistant cultivars, has the potential to enhance IPM effectiveness. Grower survey responses in the native areas (i.e., South America), early-invaded areas (i.e., first report between 2006 and 2012) and newly invaded areas (i.e., first report after 2012) showed that the control programs evolved along with the areas and time since invasion. Growers in the early-invaded areas shifted more rapidly from chemical control to biological control compared to those from the native area. In all concerned regions, the pest control failure risk following chemical insecticide applications and the high cost associated with either biological or biotechnical control methods have been the greatest concerns for growers. The information gathered from the native and/or early-invaded areas may help achieve a more effective management in newly invaded areas. Lastly, researchers are expected to break the bottlenecks of some key issues that would enable lowering application cost of novel biorational alternative management options

Effect of cold storage on the performance of Trichogramma bourarachae (Pintureau and Babault) (Hymenoptera: Trichogrammatidae)

6 p.-3 fig.-2 tb.In Tunisia, the use of the egg parasitoid trichogrammatid wasps to cope with several economic pests is gaining increasing attention. Trichogramma bourarachae (Pintureau & Babault) is among the Trichogramma wasps naturally present in Tunisia and regarded as a potential natural enemy to be used in biological control programs of many lepidopteran pests that cause economic losses. The propensity of T. bourarachae to cold storage with and without diapause induction was studied. The effect of this technique on its emergence rate and parasitic activity was investigated. The study showed that wasps of T. bourarachae treated at the induction temperature of 15 °C for 5 days can be stored at 4 ± 1 °C for more than 30 days without significant loss of their performances. By using this prestorage temperature, T. bourarachae could keep its emergence capacity (77.5%) up to 60 days of cold storage at 4 ± 1 °C. However, its parasitic activity decreased significantly (37.16%) after 45 days of cold storage. These results are promising for its mass production, transport, and release in the framework of national campaigns to control several agricultural pests of economic importance.Peer reviewe

Sliding prediction algorithm using polynomial approach for photovoltaic system energy management

7th International Conference on Control, Decision and Information Technologies (CoDIT), Prague, CZECH REPUBLIC, JUN 29-JUL 02, 2020International audienceFluctuating photovoltaic (PV) power creates a challenge for grid energy management as energy penetration increases rapidly. As a result, the forecasting of PV energy has become essential to ensure grid stability and promote optimal use of energy resources and more economical distribution. The objective of this work is to forecast PV power for a 10 min horizon, based on a set of data. This approach is used to ensure efficient operation of the fluctuating output of a PV station charging a station for electic vehicules. Simulation results show the reliability and efficiency of the technique

Suitability of Ectomyelois ceratoniae Zeller (Lepidoptera: Pyralidae) as host for two local Trichogramma species (Hymenoptera: Trichogrammatidae) and possible implications on biological control programs

In this study, laboratory tests were conducted to evaluate the suitability of Ectomyelois ceratoniae (Zeller) eggs as host for the development of two Trichogramma species: Trichogramma cacoeciae (Marchal) and Trichogramma bourarachae (Pintureau and Babault) (Hymenoptera: Trichogrammatidae) collected in Tunisia and reared on Ephestia kuehniella Zeller eggs. We also studied effects of five different temperature regimes (15, 20, 25, 30 and 35°C) on the biological traits of these two parasitoids. Results showed that eggs of E. ceratoniae were more suitable for the development of T. bourarachae. The number of parasitized eggs (15.46±2.04) as well as the emergence rate (95.78±5.10) was significantly higher compared to T. cacoeciae. For both Trichogramma species, the highest parasitism rate was observed at 30°C. At 35°C, the mean number of parasitized eggs (32.06±13.32) and the longevity (4.03±0.56) of T. bourarachae females were significantly higher compared to T. cacoeciae. The developmental time of both Trichogramma species was shorter at higher temperatures. The emergence rates were similar and relatively high in all tested temperature ranging from 80.48% to 97.92% for T. bourarachae and from 92.03% to 99.33% for T. cacoeciae

Emergence of the apricot seed wasp Eurytoma samsonowi Vassiliev (Hymenoptera: Eurytomidae) as an economic pest of apricots in Tunisia

International audienceMany eurytomid (Eurytomidae) wasps are plant parasites, and some of them are economic agricultural pests. In 2015, a new eurytomid wasp species was detected attacking apricots in the governorate of Gafsa located in the southern west region of Tunisia. Morphological and molecular identifications allowed to identify the pest as the apricot seed wasp Eurytoma samsonowi Vassiliev, a new record in Tunisia and Africa. Besides, field surveys were performed from 2017 to 2021 in order to assess the distribution of E. samsonowi in the main Tunisian apricot production areas, to characterize its symptoms of attack and to assess its damage on different apricot cultivars. The pest has limited distribution in Tunisia as it was found only in the governorates of Gafsa, Sidi Bouzid and Tozeur. Larvae of this pest feed on apricot nucellar tissues. Infested fruits either prematurely fall on the ground or turn black, become 'mummified', and remain attached to the tree. The highest infestation rates were recorded on Bayoudhi cultivar ranging from 64 to 76% depending on the year. Infestation rates registered on Bedri and Amor Leuch cultivars ranged from 24% to 51% and 27 to 53%, respectively. Therefore, this insect should be considered as an economic pest of apricots in Tunisia. Possible management measures and future outlooks are discussed

Mass trapping and bait station techniques as alternative methods for IPM of Ceratitis capitata Wiedmann (Diptera: Tephritidae) in citrus orchards

International audienc

Residual toxicity of insecticides used in Tunisian citrus orchards on the imported parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae): implications for IPM program of Ceratitis capitata (Diptera: Tephritidae)

Citrus agro-industry is globally harshened mainly by Ceratitis capitata (Wiedemann), the most worldwide destructive tephritid fruit fly species. Citrus agro-industry is one of the pillars of Tunisia economy, and by hence, harshened by this species. Tunisia has established an Integrated Pest Management (IPM) programme against citrus pests, including C. capitata, that rely on the structured use of pesticides, on the application several trapping protocols, along with pilot-scale sterile insect technique program and, since 2013, with pilot-scale releases of the braconid parasitoid Diachasmimorpha longicaudata Ashmed (Hymenoptera: Braconidae). Insecticide side-effects on parasitoids and other natural enemies are being requested for a successful implementation of biological control within any IPM programme. However, these data are almost scarce for the braconid species D. longicaudata. To this end, we have determined the side-effects of malathion, methidathion, acetamiprid, azadiractin, abamectin, deltametrin+thiacloprid and spinosad, as the most popular insecticides used in Tunisia either as fresh residues or at several aged time points, on the parasitoid D. longicaudata according the IOBC pesticide harm-classification. IOBC classification evolution of residues over time had allowed determining the best combination of pesticide applications in a structured fashion with the viable releases of D. longicaudata for the control of C. capitata in Tunisian citrus agro-ecosystems