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Pesticide residues surveillance and anomalies monitoring of ‘Maltaise demi sanguine’ (Citrus sinensis L.) oranges in packinghouses





M. Hammami2





1 Department of Plant Protection and Post-Harvest Diseases, National Institute of Agronomy of Tunisia (INAT), 1082 Tunis, Tunisia. University of Carthage.

2 Laboratory of Aromatic and Medicinal Plants, Biotechnology Center of Borj Cedria, 901, 2050 Hammam-Lif, Tunisia.

3 Laboratory of Analysis and Control of Pesticide Residues, Ministry of Agriculture Water Resources and Fishing, 1002 Tunis, Tunisia.


Abstract - For the monitoring of pesticide residues during the two agricultural seasons 2012-2013 and 2013-2014, one hundred and forty-two ‘Maltaise demi sanguine’ orange samples were collected from packinghouses. Sample analysis carried out by extraction procedure based on QuECHERS method followed by UHPLC-MS/MS chromatographic analysis showed that on both campaigns malathion, dimethoate and methidation were the only active ingredients that exceeded the Maximum Residue Levels (MRL) set by the European Union. The frequency of the MRL’s excess varied through the seasons and methidathion decreased from 85.71% to 80%, malathion declined from 54.55% to 36.36%. However, dimethoate increased from 62.5% to 75%. The upper value of concentration of each molecule varied too showing a decrease in the case of methidathion from 540 to 180 ppb and an increase in malathion from 38.64 to 93.57 ppb. Besides these tests, monitoring the export of ‘Maltaise’ oranges had shown the importance of maintenance of citrus orchards and the importance of the operation of collection to minimize the physical damages that are on the top of other post-harvest deteriorations and which decline fruit during the last operation of selection in the packing chain of oranges and represent sources of infection by fungi. 


Keywords: Oranges, pesticides, UHPLC-MS/MS, sorting gap, agricultural practices.


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Molecular characterization and genetic relationships among Tunisian Citrus rootstocks






1 Laboratory Of Plant Molecular Physiology, Biotechnology Centre Of Borj Cedria, B.P. 901, Hammam-Lif 2050, Tunisia.

2 LR Biotechnology and Bio-Geo Resources Valorization (LR11ES31), Higher Institute for Biotechnology - University of Manouba, Biotechpole of Sidi Thabet, 2020, Sidi Thabet, Ariana, Tunisia


Abstract - In this study, a set of RAPD molecular markers were applied to genotype 40 accessions belonging to 8 Citrus species growing in Tunisia. The use of 9 decamer RAPD primers to genotype the studied sample generated 127 bands out of which 122 were polymorphic with an average of 14.11 bands per primer. The percentage of polymorphism (P %) ranged an average of 94% per primer. Genotyping data were used to estimate the genetic relationships among the studied accessions using the UPGMA method. The set of RAPD markers allowed the discrimination of all the studied accessions and highlighted a genetic structure among the studied accessions. The used RAPD molecular markers were found to be a rapid and effective tool for genetic diversity and genetic relationships assessment of Citrus accessions. The observed genetic proximity among the studied Citrus accessions representing eight species expect probable easy hybridization between the studied species which could be very useful in citrus breeding programs. Our results provide a basis for further investigations looking to the improvement of Citrus rootstocks and cultivars.


Keywords: Citrus accessions, RAPD, Polymorphism, Discrimination, genetic structure.


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The Partial Root-Zone Drying Irrigation Technique (PRD): An analysis of the theoretical and practical aspects

La technique d’irrigation par dessèchement partiel des racines (PRD): Une analyse de l'aspect théorique et pratique

Scientific Review


B. Ben Nouna 1

M. Rezig 1


1 National research Institute of rural engineering, Water and Forestry, Hedi Elkarray Street, Ariana, Tunisia.


Abstract - The availability of water resources is under increasing pressure from the agricultural water demand for irrigation. In the long term, this crucial lack of resources, particularly in semi-arid and arid regions, imperatively require urgent and innovative solution for agricultural water management. In this context, the partial root-zone drying (PRD) will undertake the challenge on the plot scale. This approach provides an alternative irrigation for each side of the root system. It allows the plant, in the case of moderate water stress, triggering a chemical signaling to the leaves through the xylem to reduce the stomatal conductance, and so transpiration with a non-significant yield reduction. In fact, in the semi-arid and arid bioclimatic zones where water resources are limited, the PRD irrigation can be adopted as a technical to regularize the yield and substantial enhancement of agricultural water. This study focuses on the PRD irrigation origin and analyses its theoretical and practical aspects related to the improvement of crop water productivity. In addition, a research summary was conducted under PRD irrigation treatments and the related questions that require further study are presented in this work.


Keywords: Deficit irrigation, Partial root-zone drying (PRD), Water productivity, Stomatal conductance, Conventional irrigation


Résumé - La disponibilité des ressources en eau est soumise à une pression croissante de la demande en eau agricole des terres irriguées. A long terme, ce manque crucial de ces ressources, particulièrement dans les régions semi-arides et arides, nécessitera impérativement une solution urgente et innovatrice de la gestion de l’eau agricole. Dans cet esprit, l’irrigation par desséchement partiel des racines (PRD) pourra relever le défi à l'échelle de la parcelle. Cette approche prévoit un arrosage alternatif de chaque côté du système racinaire. Elle permet à la plante, dans le cas d’un stress modéré, de déclencher une signalisation chimique vers les feuilles par l'intermédiaire de l’xylème, pour réduire la conductance stomatique, et ainsi la transpiration avec une réduction non significative de rendement. En fait, dans les étages bioclimatiques semi-arides et arides où les ressources en eau sont limitées, l’irrigation PRD pourra être adoptée comme une technique de régularisation du rendement et de valorisation substantielle de l’eau agricole. Cet article, se focalise sur l’origine de l’irrigation PRD et l'analyse de ses aspects théoriques et pratiques relatifs à l'amélioration de la productivité de l’eau des cultures. Ce papier présente aussi une synthèse des travaux de recherche conduits sous régime d’irrigation PRD. Egalement, des questions exigent d’avantage d’étude sont évoquées dans ce travail.


Mots clés: Irrigation déficitaire, Irrigation par dessèchement partiel des racines (PRD), Productivité de l’eau, Conductance stomatique, Irrigation conventionnelle


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Acetaldehyde and lactate production after long term freezing for three thermophilic wild streptococcus thermophilus strains: evaluation in single culture










1 Characterization and Natural Resources Valorisation Laboratory (L.C.V.R) SNV-TU Faculty - Bordj Bou Arreridj University (34000) - Algeria.

2 Food and Industrial Microbiology Laboratory– Biological Sciences Faculty Oran1 University (31000) - Algeria.

Abstract - Streptococcus thermophilus is a homofermentative thermophilic lactic species, the most widely used in milk process and dairy technology, such as fermented milks, beverages, yoghurts and cheeses. It is the only urease positive, lactate and flavor compounds (acetaldehyde) production responsible. Acetaldehyde is the main aroma in yoghurts, produced from lactose, glucose, pyruvate converted from threonine and methionine. However, biosynthetic pathways and their regulation are not elucidated. By their resistance to bacteriophages attack, these species are used also in cheeses ripening. However, in all milk technological process, species are used only in mixed culture, associated with thermophilic lactic strain such as Lactobacillus bulgaricus, Lactobacillus helviticus and Bifidobacterium sp, where synergies phenomenon were observed, never in single culture. The study aimed to assess technological behavior of wild Streptococcus thermophilus strains isolated from Algerian raw milk in single culture. Strains belonging to Streptococcus thermophilus species were isolated, selected from Algerian raw milk using MRS and M17 medium, their technological skills of lactate and acetaldehyde production kinetics were explored. From all samples collected, three isolated lactic strains were selected as having unusual technological performance ST1, ST2 and ST3, milk acidification (ºD* Dornic degree) were respectively 70°D and 74°D and 69°D, flavoring power of reconstituted skim milk (in ppm: parts per million) was 0.09 ppm for ST1, 0.07 ppm for ST2, and 0.04 ppm for the strain ST3.


Keywords: Streptococcus thermophilus; Wild strains ; Selection ; Acetaldehyd ; Lacticacid


Résumé - Streptococcus thermophilus est l’une des espèces homofermentaires les plus utilisées en industrie laitière, comme starter des processus technologiques thermophiles dans la production des laits fermentés, boissons lactées acidifiées, yaourts et certains fromages à pâte dure. Elle est la seule espèce lactique thermophile, uréase positive, assurant l’acidification et l’aromatisation rapide du lait. L’acétaldéhyde, est l’arôme principal, responsable du goût caractéristique des yaourts, de certains laits fermentés et des fromages, produit à partir du lactose, du glucose et du pyruvate. Chez l’espèce S. thermophilus, l’acétaldéhyde est aussi produit à partir de la thréonine et de la méthionine. Les voies biochimiques de conversion enzymatiques des deux acides aminés et leur régulation sont peu élucidées, et sujets à des controverses. Ayant une résistance innée aux attaques des bactériophages, l’espèce S. thermophilus est utilisée dans la fabrication et la maturation des fromages à pâte cuite. Cependant, dans ces processus technologiques, l’espèce n’est utilisée qu’en culture mixte, jamais en culture pure, associée à d’autres espèces thermophiles à l’exemple de Lactobacillus bulgaricus, Lactobacillus helviticus et Bifidobacterium Sp où des phénomènes synergétiques sont observés. L’objectif de l’étude est l’exploration du comportement technologique, en culture pure, des souches (indigènes) de Streptococcus thermophilus, isolées, caractérisées et sélectionnées à partir du lait cru d’Algérie, leurs aptitudes technologiques d’acidification (production de lactate en ºD* :degré Dornic) et d’aromatisation (production d’acétaldéhyde en ppm* :partie par million) sur milieu restreint de fermentation; le lait écrémé est reconstitué à 10% W/V, à un intervalle d’incubation de 24h à 42 ºC, après une longue durée de cryoconservation. Les résultats ont donné trois souches (indigènes) sélectionnées, par leurs aptitudes d’aromatisation du lait écrémé reconstitué ST1: 0.09, ST2 : 0.07 et ST3 0.04 ppm d’acétaldéhyde. L’acidification par production du lactate en degrés Dornic (ºD) était de 70ºD (ST1), 74ºD (ST2) et 69ºD (ST3).


Mots clés: Streptococcus thermophilus, Sélection, Acétaldéhyde, Acidification, Aromatisation.


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Evaluation of azadirachta indica leave extract on hematology and biochemical profiles, organs weight and growth parameters of broiler chickens

M.B. Nodu1

M. Okpeku1, 2


D.O. Iroegbu1


1 Department of Animal Science, Niger Delta University, Wilberforce Island, Amassoma, Bayelsa State, Nigeria

2 State Key Laboratory of Genetic Resources and Evolution, Chinese Academy of Science (CAS, Kunming Institute of Zoology, China

Abstract - We evaluate the Effect that neem leaf extract on growth, haematology and biochemical profiles and organs weight of broiler chickens to justify its inclusion in the diet of growing broiler chickens. 120 day old chicks divided into four treatment groups T1, T2, T3 and T4 of thirty (30) birds each were administered clean drinking water with 0g, 3g, 4g and 5g neem extract respectively. Impacts of neem extract treatments on growth indices suggested that Neem extract favored growth with final body weight range of 2447 and 2620g. Organ weights showed no deviation from standard values for healthy broiler birds. Hematology and serum biochemistry values were in conformity with standards for healthy broiler birds. Birds on 3g of Neem extract in their drinking water out performed birds in other treatments in assessed growth rate indices. We therefore conclude that 3g of Neem extract in their drinking water growing broiler birds encourages healthy growth and may serve as supplements for antibiotics, especially when birds are raised in areas with minimal access to veterinary service.



Keywords:  Azadirachta indica, Biochemistry, Broiler, Chicken, Hematology, Organ.


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This article is published under license to Journal of New Sciences. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

CC BY 4.0