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Bioécologie, Cartographie et Identification de foreur rhinocéros l’Oryctes spp. du palmier dattier (Phoenix dactylifera L.) dans la région d’El Oued, Algérie.

2025-10-27T08:51:22Z

Titre: Bioécologie, Cartographie et Identification de foreur rhinocéros l’Oryctes spp. du palmier dattier (Phoenix dactylifera L.) dans la région d’El Oued, Algérie. Auteur(s): Rais Sana Résumé: This study focuses on the rhinoceros beetle Oryctes spp. of date palms, conducted at Taleb Larbi and Douar El Ma sites in El Oued, Algeria, over a two-year period (2022-2024), it aims to understand the biological and ecological aspects of of this pest. Observations in the natural environment reveal that Oryctes agamemnon follows a univoltine life cycle, with the flight period starting in April and extending until December, with the adult population peaking in August. Adults hibernate from January to March, while the larvae, present at all developmental stages throughout the year, continue to develop. Laboratory studies, conducted at a temperature of 26 ± 1°C, humidity of 55 ± 5%, and a photoperiod of 13/11 hours, show that the complete life cycle of Oryctes agamemnon lasts approximately 314.87 ± 7.79 days, with the larval stages accounting for 66% of the total cycle. Among these stages, the third larval stage is the longest, lasting on average 124.58 days. The results also indicate a maximum mortality rate at the embryonic stage, reaching 20.45%. Both adults and larvae of Oryctes cause significant damage to date palms. The larvae primarily attack the roots and trunk, tunneling through and damaging the structure and growth of the palm. Adults also target the trunk and can reach the crown, perforating and damaging the plant tissues, weakening the tree. These activities compromise the health of the palm, promoting severe infestations and threatening its survival. The identification of mites associated with Oryctes agamemnon subsp. arabicus led to the discovery of a new species of mite from the Laelapidae family, Hypoaspis arabicus Rais and Kontschán, sp. nov. (Acari: Laelapidae). This mite species was observed throughout the various developmental stages of the insect. Analysis of the NDVI index at the study sites from 1990 to 2024 shows a general upward trend. However, a stabilization of values has been observed since 2012. This stabilization could be linked to the emergence of the pest Oryctes agamemnon, whose negative impact limits vegetation growth and slows the evolution of the NDVI index. The identification of Oryctes specimens was carried out using morphological and molecular methods with the COI marker, confirming that all individuals belong to the subspecies Oryctes agamemnon subsp. arabicus, with slight genetic diversity observed among populations through MASH analysis. These results offer insights for developing integrated pest management strategies and tailoring interventions to the biological cycle of the species. This will help protect local date palm plantations from damage caused by this pest, thus contributing to the sustainability of date palm cultivation in the region. Description: Protection des végétaux

Ecologie trophique de l’étourneau sansonnet (Sturnus vulgaris) en milieu agricole

2025-10-27T08:46:14Z

Titre: Ecologie trophique de l’étourneau sansonnet (Sturnus vulgaris) en milieu agricole Auteur(s): Rabie Djalila Résumé: The Common starling (Sturnus vulgaris) is an invasive species in Algeria, including in the Ziban region. A study of biometrics, sexual dimorphism, allometry, food availability and trophic menu of this species is conducted at the level of the Ziban region. Biometrics of this species was studied following body measurements of 177 individuals it was found that the weight is 74.66± 8.82 g, the total length is 21.13± 1.26 cm, and the wingspan is 37.83± 1.64 cm, the folded wing is 12,67± 0.53 cm, the length of the beak is 2.62± 0.37 cm, the length of the beak is 2.62± 0.37 cm, the head measures on average 5.23± 0.20 cm, and the length of the tarsus is on average 3.02± 0.28 cm. The external biometrics of adult starlings measured showed a high degree of sexual dimorphism, the average weight of the male is 78.82± 6.42 g, and the female is 70.45± 8.96 g. The total length of the male’s body is 21.47 ±1.26 cm, and the female is 20.78± 1.17 cm. The wingspan of males is 38.12± 1.48 cm and females is 37.54± 1.75 cm. The folded wing of males is 12.79± 0.57 cm, and females is 12.55± 0.47 cm. The length of the beak in males is 2.63± 0.19 cm, and in females is 2,60 ±0.21 cm. The heads of males average 5.30± 0.32 cm, and those of females 5.16± 0.35 cm. And the length of the tarsus of the male is on average 3.02± 0.27 cm, and the female 3.03± 0.29 cm. The results show that the variation between the sexes was significant, except for the tarsus. An allometric correlation is marked between the different metrics examined and morphological parameters that indicate sexual dimorphism between the two sexes (♂= 89; ♀= 88) and this analysis shows a minor relationship between most of the measured parameters and the total length of the body and weight in both sexes. On the other hand 185 spontaneous plants were identified and 4900 specimens of insects collected by both methods (Barber pots and yellow traps) in 6 study stations in the Ziban region. The species counted belong to 8 orders with 38 families and 78 species. While after dissection of the individuals 9 species were found or Olea europaea (with 136 nuclei and pulp) and Phoenix dactylifera (with 126 pulp) are the most consumed by the starling, and 881 individuals of animal prey were identified, of which 53 species, spread over 18 orders and 34 families, whose beetles are the most represented. The values of the diversity of Shannon-Weaver at the level of the different environments in Ziban, are between 2.23 bit in the Sidi Okba region and 4.40 at the level of I.T.D.A.S. The values of E are relatively close to 1, between 0.68 in El Outaya and 0.89 in Tolga. These data show that the diet of the European starling in the Ziban region can be classified as diverse. And finally the calculated Ivelv index shows that there are items ingested by the starling and are present in the trophic media, while there are other individuals that are present in the media while are not found in the trophic menu. Description: Protection des végétaux

Impact de l’irrigation des cultures maraichères par les eaux piscicoles dans la région de Biskra.

2025-10-27T08:35:12Z

Titre: Impact de l’irrigation des cultures maraichères par les eaux piscicoles dans la région de Biskra. Auteur(s): MECHOUMA Abdelhakim Résumé: Saving water and its rational management in crop irrigation have become an important issue to ensure the sustainability of agriculture in arid and semi-arid regions, particularly with the effects of climate change on these regions. This work was carried out at the level of the Technical Institute for the Development of Saharan Agronomy (ITDAS); its objective is to study the impact of the use of water from fish farming in the irrigation of vegetable crops. (Potatoes and peppers in greenhouses) under salinity conditions (soil and irrigation water), in this experiment we compared the effect of water from fish farming on the plants and the soil with that of drilling water, the parameters studied are the height of the plants, the fruit yield and the physic-chemical characteristics of the soil. The results obtained showed that the use of fish water in irrigation can improve the vegetative growth of cultivated plants and their fruit yields, in addition it can exert a beneficial effect on the soil by increasing the rate of organic matter, the rate of total nitrogen and it can also lower the pH of the soil. The value that this practice can add to agriculture is the reuse of this waste water in irrigation which is considered as an unconventional water source and at the same time the reduction of the use of synthetic fertilizers in the crop management. Description: Production et amélioration végétale

Evaluation de la Contribution des carbonates dans la rétention des polluants métalliques dans les sols

2025-10-27T08:33:05Z

Titre: Evaluation de la Contribution des carbonates dans la rétention des polluants métalliques dans les sols Auteur(s): Kessab Amira Résumé: Pollution by hexavalent chromium is a serious problem that can affect both human health and the environment. This study aims to evaluate the contribution of carbonates in chromium sorption in soils with varying carbonate concentrations in the carbonate-rich region of Djelfa. The retention study was based on three soils containing different concentrations of total limestone. It began with a physico-chemical analysis of the soils, followed by a sorption study where several sorption parameters were modified: contact time, pH, temperature, agitation speed, initial chromium concentration, and finally, a comparison of chromium retention on the three soils relative to their carbonate content. The results showed that sorption followed a pseudo-second-order kinetics with a high regression coefficient (R² between 0.9984 and 0.997). The activation energies were 12.85 and 16.44 kJ/mol, indicating that the sorption mechanism is physical in nature. The data were compatible with the Freundlich model, but not with the Langmuir and Jovanovic models, suggesting that adsorption occurs on heterogeneous surfaces. Adsorption was spontaneous (∆G0 < 0) (-7.4 / -9.49) and exothermic (∆H0 < 0) (-14.07 / 15.54), meaning it is favored at low temperatures. Our results indicate that using carbonates, such as ground limestone, can help stabilize heavy metals in contaminated soils, reducing their toxicity and improving soil fertility. This method is simple and cost-effective, supporting both agriculture and soil decontamination. It is essential to train farmers on its proper application. While larger-scale studies are needed, testing on polluted lands will help assess the effectiveness and costs of this approach Description: hydro-pédologie en régions arides