The aim of this study is to evaluate the antioxidant power of the olive oil against the cation ra... more The aim of this study is to evaluate the antioxidant power of the olive oil against the cation radical ABTS•+, according to cultivars: Chemlali, Arbequina and Koroneiki; culture modes: extensive and intensive; ripening stages: November and December corresponding stages and study year: 2017 and 2018. Radical percentage inhibition (PI), Trolox equivalent antioxidant capacity (TEAC), inhibitory concentration required to scavenge 50% of radicals (IC50) and principal component analysis (ACP) were determined. The oil of the Tunisian main cultivar Chemlali, cultivated in extensive mode, has the best scavenging power with the lowest IC50 values of 9.3, 10.8, 9.65 and 10.4 µg/ml respectively in all the ripening stages. Also, at the lowest tested concentration of 20 µg/ml, this oil has the highest TEAC values, respectively 2.28 and 2.20 in November of 2017 and 2018. For the introduced cultivars, Koroneiki presents better performance than Arbequina, in intensive mode, with IC50 ranged from 9.6...
Climate change has become a widespread serious phenomenon. Its effects are related to variability... more Climate change has become a widespread serious phenomenon. Its effects are related to variability in local climates rather than in global climatic patterns. Mediterranean countries are the most concerned where olive tree constitutes one of the most dynamic cultivations. This work focuses on the research for new indicators of the adaptation of the olive tree to several climatic conditions. ‘Chemlali’ and ‘Chetoui’ represent the primary Tunisian olive tree cultivars. To adapt to different climatic conditions characterizing the north, the center and the south of the country (superior semiarid, inferior semiarid and inferior arid respectively), these varieties synthesize many interesting compounds that have been screened and compared. Indeed, the methanolic extracts from ‘Chemlali’ and ‘Chetoui’ leaves have been tested for their antioxidant activities. The chemical compositions of the extracts have been quantified in antioxidants. Both ‘Chemlali’ and ‘Chetoui’ exhibited a significant an...
The accurate monitoring of soil salinization plays a key role in the ecological security and sust... more The accurate monitoring of soil salinization plays a key role in the ecological security and sustainable agricultural development of semiarid regions. The objective of this study was to achieve the best estimation of electrical conductivity variables from salt-affected soils in a south Mediterranean region using Sentinel-2 multispectral imagery. In order to realize this goal, a test was carried out using electrical conductivity (EC) data collected in central Tunisia. Soil electrical conductivity and leaf electrical conductivity were measured in an olive orchard over two growing seasons and under three irrigation treatments. Firstly, selected spectral salinity, chlorophyll, water, and vegetation indices were tested over the experimental area to estimate both soil and leaf EC using Sentinel-2 imagery on the Google Earth Engine platform. Subsequently, estimation models of soil and leaf EC were calibrated by employing machine learning (ML) techniques using 12 spectral bands of Sentinel-...
In the present study, methanol, acetone and petroleum ether extracts of olive leaves were investi... more In the present study, methanol, acetone and petroleum ether extracts of olive leaves were investigated for their insecticidal activity against Myzus persicae and deterrent effect on Phthorimaea operculella under laboratory conditions. Different concentrations 0.1%, 1% and 10% were implemented in the experiment. The results revealed that acetone and methanol extracts caused 100% mortality of M. persicae at 10%. Tests on P. operculella generated a very pronounced deterrence of oviposition and larval penetration at 10%. Data indicate that, the acetone extract proved to be most deterrent against larval penetration at 10 % in comparison with other tested extracts and concentrations with 71.7% of deterrent index. Moreover, the highest deterrent effect of oviposition was recorded to acetone extract with 25.9%, 65.2% and 93.3% at 0.1, 1 and 10%, respectively. Therefore, this study provides first report on the insecticidal and deterrent activities of olive leaf extracts against M. persicae a...
The table olive cultivar ‘Meski’ was subjected to two stresses related to water, scarcity, and sa... more The table olive cultivar ‘Meski’ was subjected to two stresses related to water, scarcity, and salinity. Anatomical adaptations of leaves, stems and roots were studied and compared, to value the water use efficiency of the tree. Two stress levels were adopted corresponding to moderate and severe levels. Thus, the trees behaviour was influenced by the stress type and intensity. The aerial part of the trees showed more adaptation modes than the underground part. Under both stresses, plants have fortified the protection of the leaf tissues by developing upper envelope and multiplying the trichomes. Plants reinforced the support tissues by multiplying the collenchyma and sclereids, and have amplified the transport tissues by enhancing vascularity through multiplying the number of conductive vessels. However, different behaviours seemed to be specific to each stress such an enlargement of liber and reduction of wood in the drought stress and a restriction of liber and wood tissues in sal...
The study of olive trees water requirements allows a better water management by using more accura... more The study of olive trees water requirements allows a better water management by using more accurate methods including maximum parameters of the continuum soil-plant- atmosphere. The Penman-Monteith equations is consideredas the most rational approach and the most reliable for calculating evapotranspiration. Only this approach necessarily requires an important number of climate parameters. The use of other equations, less complicated and using less climate parameters may be a reliable and efficient alternative. This experimental study was carried out on two cultivars cv. "Meski" and cv. "Chemlali" conducted in the intensive system in different bioclimatic stages (Subhumid, Semi-Arid and Arid) in Tunisia. This work aims to estimate olive trees water needs using evapotranspiration calculation in three different bioclimatic stages. For that, we compared the Penman-Monteith formula with Blaney-Criddel, Hargreaves-Temperature, Hargreaves- Radiation and Priestley-Taylor...
The study of olive trees water requirements allows a better water management by using more accura... more The study of olive trees water requirements allows a better water management by using more accurate methods including maximum parameters of the continuum soil-plant- atmosphere. The Penman-Monteith equations is consideredas the most rational approach and the most reliable for calculating evapotranspiration. Only this approach necessarily requires an important number of climate parameters. The use of other equations, less complicated and using less climate parameters may be a reliable and efficient alternative. This experimental study was carried out on two cultivars cv. "Meski" and cv. "Chemlali" conducted in the intensive system in different bioclimatic stages (Subhumid, Semi-Arid and Arid) in Tunisia. This work aims to estimate olive trees water needs using evapotranspiration calculation in three different bioclimatic stages. For that, we compared the Penman-Monteith formula with Blaney-Criddel, Hargreaves-Temperature, Hargreaves- Radiation and Priestley-Taylor...
The aim of this study is to evaluate the antioxidant power of the olive oil against the cation ra... more The aim of this study is to evaluate the antioxidant power of the olive oil against the cation radical ABTS•+, according to cultivars: Chemlali, Arbequina and Koroneiki; culture modes: extensive and intensive; ripening stages: November and December corresponding stages and study year: 2017 and 2018. Radical percentage inhibition (PI), Trolox equivalent antioxidant capacity (TEAC), inhibitory concentration required to scavenge 50% of radicals (IC50) and principal component analysis (ACP) were determined. The oil of the Tunisian main cultivar Chemlali, cultivated in extensive mode, has the best scavenging power with the lowest IC50 values of 9.3, 10.8, 9.65 and 10.4 µg/ml respectively in all the ripening stages. Also, at the lowest tested concentration of 20 µg/ml, this oil has the highest TEAC values, respectively 2.28 and 2.20 in November of 2017 and 2018. For the introduced cultivars, Koroneiki presents better performance than Arbequina, in intensive mode, with IC50 ranged from 9.6...
Climate change has become a widespread serious phenomenon. Its effects are related to variability... more Climate change has become a widespread serious phenomenon. Its effects are related to variability in local climates rather than in global climatic patterns. Mediterranean countries are the most concerned where olive tree constitutes one of the most dynamic cultivations. This work focuses on the research for new indicators of the adaptation of the olive tree to several climatic conditions. ‘Chemlali’ and ‘Chetoui’ represent the primary Tunisian olive tree cultivars. To adapt to different climatic conditions characterizing the north, the center and the south of the country (superior semiarid, inferior semiarid and inferior arid respectively), these varieties synthesize many interesting compounds that have been screened and compared. Indeed, the methanolic extracts from ‘Chemlali’ and ‘Chetoui’ leaves have been tested for their antioxidant activities. The chemical compositions of the extracts have been quantified in antioxidants. Both ‘Chemlali’ and ‘Chetoui’ exhibited a significant an...
The accurate monitoring of soil salinization plays a key role in the ecological security and sust... more The accurate monitoring of soil salinization plays a key role in the ecological security and sustainable agricultural development of semiarid regions. The objective of this study was to achieve the best estimation of electrical conductivity variables from salt-affected soils in a south Mediterranean region using Sentinel-2 multispectral imagery. In order to realize this goal, a test was carried out using electrical conductivity (EC) data collected in central Tunisia. Soil electrical conductivity and leaf electrical conductivity were measured in an olive orchard over two growing seasons and under three irrigation treatments. Firstly, selected spectral salinity, chlorophyll, water, and vegetation indices were tested over the experimental area to estimate both soil and leaf EC using Sentinel-2 imagery on the Google Earth Engine platform. Subsequently, estimation models of soil and leaf EC were calibrated by employing machine learning (ML) techniques using 12 spectral bands of Sentinel-...
In the present study, methanol, acetone and petroleum ether extracts of olive leaves were investi... more In the present study, methanol, acetone and petroleum ether extracts of olive leaves were investigated for their insecticidal activity against Myzus persicae and deterrent effect on Phthorimaea operculella under laboratory conditions. Different concentrations 0.1%, 1% and 10% were implemented in the experiment. The results revealed that acetone and methanol extracts caused 100% mortality of M. persicae at 10%. Tests on P. operculella generated a very pronounced deterrence of oviposition and larval penetration at 10%. Data indicate that, the acetone extract proved to be most deterrent against larval penetration at 10 % in comparison with other tested extracts and concentrations with 71.7% of deterrent index. Moreover, the highest deterrent effect of oviposition was recorded to acetone extract with 25.9%, 65.2% and 93.3% at 0.1, 1 and 10%, respectively. Therefore, this study provides first report on the insecticidal and deterrent activities of olive leaf extracts against M. persicae a...
The table olive cultivar ‘Meski’ was subjected to two stresses related to water, scarcity, and sa... more The table olive cultivar ‘Meski’ was subjected to two stresses related to water, scarcity, and salinity. Anatomical adaptations of leaves, stems and roots were studied and compared, to value the water use efficiency of the tree. Two stress levels were adopted corresponding to moderate and severe levels. Thus, the trees behaviour was influenced by the stress type and intensity. The aerial part of the trees showed more adaptation modes than the underground part. Under both stresses, plants have fortified the protection of the leaf tissues by developing upper envelope and multiplying the trichomes. Plants reinforced the support tissues by multiplying the collenchyma and sclereids, and have amplified the transport tissues by enhancing vascularity through multiplying the number of conductive vessels. However, different behaviours seemed to be specific to each stress such an enlargement of liber and reduction of wood in the drought stress and a restriction of liber and wood tissues in sal...
The study of olive trees water requirements allows a better water management by using more accura... more The study of olive trees water requirements allows a better water management by using more accurate methods including maximum parameters of the continuum soil-plant- atmosphere. The Penman-Monteith equations is consideredas the most rational approach and the most reliable for calculating evapotranspiration. Only this approach necessarily requires an important number of climate parameters. The use of other equations, less complicated and using less climate parameters may be a reliable and efficient alternative. This experimental study was carried out on two cultivars cv. "Meski" and cv. "Chemlali" conducted in the intensive system in different bioclimatic stages (Subhumid, Semi-Arid and Arid) in Tunisia. This work aims to estimate olive trees water needs using evapotranspiration calculation in three different bioclimatic stages. For that, we compared the Penman-Monteith formula with Blaney-Criddel, Hargreaves-Temperature, Hargreaves- Radiation and Priestley-Taylor...
The study of olive trees water requirements allows a better water management by using more accura... more The study of olive trees water requirements allows a better water management by using more accurate methods including maximum parameters of the continuum soil-plant- atmosphere. The Penman-Monteith equations is consideredas the most rational approach and the most reliable for calculating evapotranspiration. Only this approach necessarily requires an important number of climate parameters. The use of other equations, less complicated and using less climate parameters may be a reliable and efficient alternative. This experimental study was carried out on two cultivars cv. "Meski" and cv. "Chemlali" conducted in the intensive system in different bioclimatic stages (Subhumid, Semi-Arid and Arid) in Tunisia. This work aims to estimate olive trees water needs using evapotranspiration calculation in three different bioclimatic stages. For that, we compared the Penman-Monteith formula with Blaney-Criddel, Hargreaves-Temperature, Hargreaves- Radiation and Priestley-Taylor...
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