Etude du comportement de ponte du carpocapse (Cydia pomonella L.) (Lepidoptera ; Tortricidae) sur deux varietes de pommier (Malus domestica BORKH.)

Le carpocapse, Cydia pomonella L. (Lepidoptera : Tortricidae) figure parmi les principaux ravageurs des pommes et des poires dans la région de  Batna (Algérie). Le présent travail montre la première étude, à l’échelle nationale, sur le comportement de ponte de ce ravageur. La souche  utilisée a été récupérée d’un verger situé dans la région de Tazoult  (Batna). Le choix de deux variétés de pommier (Golden Delicious et Starkrimson), du point de vue de la ponte en conditions naturelles et le choix de la région de Tazoult, réside dans le fait que dans cette région, ces deux variétés sont sensibles au carpocapse. L’observation du comportement de ponte du carpocapse sur arbre, en milieu naturel et en conditions de non-choix dans la région de Limbiridi (Batna), confirme que la variété Golden Delicious est plus sensible à la ponte que la variété Starkrimson. Différentes étapes comportementales sont observées sur les deux variétés étudiées : atterrissage à la surface du pommier, visite des différents sites, examen du site et l’acceptation de ponte. La ponte est accompagnée par l’examen du site par balayage de l’ovipositeur.Mots-clés : Lepidoptera, Cydia pomonella, Golden Delicious, Starkrimson, comportement de ponte. The codling moth, Cydia pomonella L. (Lepidoptera : Tortricidae) is the major pest of apples and pears in the region of Batna (Algeria). This work is the first nationally study about codling moth egg-laying behavior.  Insects used in the study have been collected from the region of Tazoult (Batna). Counting eggs on the two apple tree varieties (Golden Delicious and Starkrimson) in choice conditions in the region of Tazoult (Batna) showed that both varieties are susceptible to codling moth egg-laying, with a slight preference of Golden Delicious. The observation of egg-laying behavior of codling moth on trees in natural and non-choice conditions in the region of Limbiridi (Batna), confirmed that Golden Delicious variety is more preferred for egg-laying than Starkrimson. Different behavioural steps are observed on both studied varieties : landing on the surface of apple tree, visiting different sites, site examination and acceptance of egg-laying. The egglaying is accompanied by an examination of the site by scanning of the ovipositor.Key words : Lepidoptera, Cydia pomonella, Codling moth, Golden  Delicious, Starkrimson, egg-laying behavior

HERIMITIAN SOLUTIONS TO THE EQUATION AXA* + BYB* = C, FOR HILBERT SPACE OPERATORS

Let A, A_{1},  A_{2}, B, B_{1}, B_{2}, C_{1} and C_{2} be linear bounded operators on Hilbert spaces. In this paper, by using generalized inverses, we establish necessary and sufficient conditions for the existence of a common solution and give the form of the general common solution of the operator equations A_{1}XB_{1}=C_{1} and A_{2}XB_{2}=C_{2}, we apply this result to determine new necessary and sufficient conditions for the existence of Hermitian solutions  and give the form of the general Hermitian solution to the operator equation AXB=C. As a consequence, we give necessary and sufficient condition for the existence of Hermitian solution to the operator equation AXA^{*}+BYB^{*}=C

Effect of the Exogenous Foliar Sprays of Micro-Doses of Fructose and Glucose, on Egg-Laying of Cydia Pomonella L. and its Oviposition Site Selection in Apple Orchard

A better understanding of the new concept of ‘sweet immunity’, represented by the use of sugars to reduce the susceptibility of plants to pests, would help implication of this knowledge within a new apple orchard protection strategy against Cydia pomonella. Behavioral and effect of two sugars, fructose (100 ppm), glucose (100 ppm), and chemical insecticide (deltamethrin) on egg-laying of C. pomonella were evaluated on two varieties (Golden delicious and Royal gala). The spraying of the two sugars, besides the insecticide, during the first, the third flight on the Golden delicious variety and the fourth flight on the Royal gala variety reduced significantly the number of eggs laid on leaves and fruits compared with control. Preferred oviposition sites for moths of all flights were leaves than fruits, whereas no eggs were found on branches. Between six studied sites, more eggs were laid on upper surface of the corymb leaves (51.67 %) in all flights of two varieties than fruit with 8.2 %, and none on the branches. Our results indicate that the responses of the codling moth egg-laying to foliar sprays of sugars are probably due to gustatory cues that reduce C. pomonella egg-laying, and they may have their importance in the signaling pathways of plant resistance to Lepidoptera

On the Browder's theorem of an elementary operator

Let H be an infinite complex Hilbert space and consider two bounded linear operators A, B ∈ L(H). Let Lᴀ ∈ L(L(H)) and Rʙ ∈ L(L(H)) be the left and the right multiplication operators, respectively, and denote by dᴀ;ʙ ∈ L(L(H)) either the elementary operator Δᴀ;ʙ (X) = (Lᴀ Rʙ ̶ I)(X) = A X B ̶̶ X or the generalized derivation δᴀ, ʙ (X) = (Lᴀ ̶ Rʙ)(X) = AX ̶ XB. This paper is concerned with the problem of the transference of Browder’s theorem from operators A and B to their elementary operator dᴀ,ʙ. We give necessary and sufficient conditions for dᴀ,ʙ to satisfy Browder’s theorem. Some applications for completely hereditarily normaloid operators are given.peerReviewe

Optimization of geometrical parameters of covers and hoops of metal packaging boxes

Finding the best compromise between economic, mechanic and technologic imperatives is still being one of the most important goal for the engineer. Working methods to achieve this goal of excellence have advanced considerably in recent years. Nowadays, optimization programs are included in many commercial codes of finite elements (ANSYS, LS-DYNA, Msc-Marc,... ), so that optimization can be made from the design phase. Therefore, it may be a part of an integrated design process. In this work we try to find the ideal geometric parameters of covers and hoops of metal packaging boxes. A similar approaches were introduced in the past, we can presents the following example: To minimize the weight of can ends of beverage cans, K.Yamazaki et al. (2006). (Yamazaki. [1]). applied the method of response surface approximation to develop the can ends. The geometric parameters of the sheet metal are considered as design variables to optimize. The strategy is to combine between the design of experiments using orthogonal arrays and a series of simulations with the finite elements code Msc Marc to approximate the expression of stresses and displacements at the center of can end according to design variables. Finally a numerical optimization program, in this case, DOT from Vanderplaats, is used to minimize the weight, under three constraints. In our study, we have shape optimization of metal boxes under internal pressure, with the condition to avoid opening the cover, the objective function to optimize is difficult to interpret analytically, we opted for an approximation method based on design of experiments coupled with the finite elements code ABAQUS. The optimization method applied is hybrid in a way because it use both the response surfaces methodology and nonlinear constrained optimization algorithm (SQP). It is divided into two steps: A first step will allow us to express the objective function which is the contact pressure between the lid and hoop by a quadratic polynomial formula with the Box-Behnken method. A second step is to maximize under constraints, the contact pressure at the last increment before final opening of the cover, this maximization is solved by the SQP algorithm

Variability influence of the volatile compounds of three algerian date cultivars (Phoenix dactylifera L.) on infestation rates of the date moth [(Ectomyelois ceratoniae Zell. (Lepidoptera: Pyralidae)]

The date moth Ectomyelois ceratoniae Zeller (Lepidoptera; Pyralidae) is a serious pest for the dates production in Algerian oasis. Its dangerousness resides in its wide geographic distribution on various bioclimatics stages and his polyphagia on various hosts. In this context, to find out the impact of the dates volatile compounds on the date moth oviposition behavior. To do this, we conducted the following study, which is divided into two parts, one in the field and the other in the laboratory. This study investigated the effect of the biochemical profiles of three Algerian date cultivars (Deglet-Nour, Ghars and Degla-Beidha) on the infestation rates of the date moth. The monitoring infection rates in the field produced the following results: during the campaigns from 2011/2012 to 2014/2015 at the INRAA Sidi Mahdi-Touggourt station (Algeria), revealed that the cultivar Deglet-Nour is the most affected with a rate of 18.84%, followed by Ghars with 10.28% then Degla-Beidha with 6.66%. As for the extracts analysis of the three date cultivars with hexane were identified and quantifie via coupling gas chromatography / mass spectrometry (GC/MS). The analysis of the volatile compounds of the cultivars studied allowed to identify 110 compounds distributed in eight chemical classes (hydrocarbons (saturated aliphatic hydrocarbons, unsaturated aliphatic hydrocarbons, unsaturated monocyclic hydrocarbons, saturated monocyclic hydrocarbons, aromatic hydrocarbons, terpene hydrocarbons), alcohols, aldehydes, esters, ketones, amides, phenols and carboxylic acids), whose compounds are distributed as follows: 72 compounds for the Deglet-Nour, 38 compounds for the cultivar Ghars and 29 compounds for Degla-Beidha

Use of sugars as alternative to chemical control: trials carried out on thrips associated with olive tree

Foliar spraying of infradoses of sugars (glucose, fructose or sucrose) induces plant resistance to pests that are particularly difficult to combat. These include thrips, which can cause flower abortion, stunting and deformation of olives, resulting in significant crop losses. Randomised block trials were conducted during three years (2017 to 2019), on two cultivars Chemlal and Sigoise, in an olive grove in Batna province (Algeria), with the aim of determining the most effective dose and type of sugar on thrips populations, and to evaluate the effectiveness of combining sugar with chemical treatment, as well as the possibility of reducing the dose of the latter. The results showed that sucrose at a concentration of 100 ppm was the most effective and that the efficacy of sucrose was higher than that of glucose and fructose, on both cultivars tested. The combination of sucrose with insecticide resulted in a synergistic effect and a higher efficacy gain than sucrose alone, and that the efficacy of the combination sucrose + insecticide at low dose D1 was identical to the combination sucrose + insecticide at recommended dose D2. It is therefore possible to reduce the chemical insecticide dose while maintaining good treatment efficacy for the control of these pests

Foliar application of microdoses of sucrose to reduce codling moth Cydia pomonella L. (Lepidoptera: Tortricidae) damage to apple trees

Abstract BACKGROUND The effects of foliar applications of microdoses of sucrose to reduce the damage by the codling moth have been reported from nine trials carried in France and Algeria from 2009 to 2014. The activity of sucrose alone was assessed by comparison with an untreated control and some treatments with the Cydia pomonella granulovirus or a chemical insecticide. The addition of sucrose to these different treatments was also investigated. RESULTS The application of sucrose at 0.01% reduced the means of infested fruits with a value of Abbott's efficacy of 41.0 ± 10.0%. This involved the induction of resistance by antixenosis to insect egg laying. Indeed, it seems that acceptance of egg laying on leaves treated with sucrose was reduced. The addition of sucrose to thiacloprid improved its efficacy (59.5% ± 12.8) by 18.4%. However, the sucrose had no added value when associated with C. pomonella granulovirus treatments. CONCLUSION Foliar applications of microdoses of sucrose every 20 days in commercial orchards can partially protect against the codling moth. Its addition to thiacloprid increases the efficacy in integrated control strategies, contrary to C. pomonella granulovirus treatments. This work opens a route for the development of new biocontrol strategies