This study was carried out to assess plasticity to drought of 30 adult fig cultivars,based on a screening of leaf structural and functional traits under sustained deficit irrigation,corresponding to 60%of crop evapotr...This study was carried out to assess plasticity to drought of 30 adult fig cultivars,based on a screening of leaf structural and functional traits under sustained deficit irrigation,corresponding to 60%of crop evapotranspiration.All trees,three per cultivar,are planted in an ex-situ collection in Sais plain,northern Morocco.The measurements concerned leaf area,blade thickness,trichomes density,trichome hair length,stomatal density,stomatal dimensions,stomatal area index,chlorophyll concentration index,relative water content,stomatal conductance,leaf temperature,water loss in detached leaves,cuticular wax content,proline content,total phenolic compounds,and total soluble sugars.The ranking of cultivars regarding drought tolerance was established based on a two-level clustering approach,primarily relying on chlorophyll concentration index and secondarily on water status traits.Results showed significant genotypic variations for all measured traits,except phenolic compounds content.Correlations between structural and functional traits have pinpointed blade thickness and trichome hair length as the key indicators of fig drought tolerance,owing to their involvement in maintaining chlorophyll content under water stress conditions.The extent of the variations shows that fig leaf is endowed with a wide structural and functional diversity,which can give to the species potential for resilience to various environmental stresses,including drought.Among the cultivars assessed,two exotic varieties,“Kadota”and“Royal Blanck”,as well as four local cultivars,namely,“Ferqouch Jmel”,“El Qoti Labied”,“Hamra”and“Fassi”showed the highest drought plasticity level.展开更多
Water restrictions management for fruit rosaceous during slowdown periods of fruit growth can increase water use efficiency and improve fruit quality without reducing significantly their yield. In this context, two wa...Water restrictions management for fruit rosaceous during slowdown periods of fruit growth can increase water use efficiency and improve fruit quality without reducing significantly their yield. In this context, two water restriction levels were tested during four consecutive seasons (2007-2011) in peach, plum and almond trees during slowdown periods of fruit growth corresponding to stage II for peach and plum and to stages II and III for almond. Water was applied by drip irrigation to produce different water-application treatments of 50% ETc (T50) and 75% ETc (T75) of non-stressed trees irrigated at 100% ETc (T100). The response of trees is presented only for the last season of the experiment (2010-2011) where the effect of the applied water stress is more pronounced. Results show that the effect of water restrictions varied depending on the species. Yield and fruit size were reduced significantly for peach only under treatment T50. Fruit quality was improved for this species with an increase of brix refractometric index and a decrease of acidity. These parameters were evolved in the same manner for plum but the observed differences were not significant. For almond, kernel quality remained unaffected by water restriction at T75. However, the epidermal wrinkles of kernels were more embossed, in response to treatment T50, which affected their appearance. Except leaf area, the evolution of shoots growth, chlorophyll content and leaf temperature showed that the physiology of all species was affected by water stress created by the application of the two irrigation treatments but without profound influence, particularly in plum. In conclusion, irrigation-water may be economized during slowdown periods of fruit growth without major negative effect up to 25% ETc for peach and almond and up to 50% ETc for plum.展开更多
This study was performed to examine the separate and simultaneous influence of predictive models’choice alongside sample ratios selection in soil organic matter(SOM).The research was carried out in northern Morocco,c...This study was performed to examine the separate and simultaneous influence of predictive models’choice alongside sample ratios selection in soil organic matter(SOM).The research was carried out in northern Morocco,characterized by relatively cold weather and diverse geological conditions.The dataset herein used accounted for 1591 soil samples,which were randomly split into the following ratios:10%(∼150 sample ratio),20%(∼250 sample ratio),35%(∼450 sample ratio),50%(∼600 sample ratio)and 95%(∼1200 sample ratio).Models herein involved were ordinary kriging(OK),regression kriging(RK),multiple linear regression(MLR),random forest(RF),quantile regression forest(QRF),Gaussian process regression(GPR)and an ensemble model.The findings in the study showed that the accuracy of SOM prediction is sensitive to both predictive models and sample ratios.OK combined with 95%sample ratio performed equally to RF in conjunction with all the sample ratios,as the latter did not show much sensitivity to sample ratios.ANOVA results revealed that RF with a∼10%sample ratio could also be optimum for predicting SOM in the study area.In conclusion,the findings herein reported could be instrumental for producing cost-effective detailed and accurate spatial estimation of SOM in other sites.Furthermore,they could serve as a baseline study for future research in the region or elsewhere.Therefore,we recommend conducting series of simulation of all possible combinations between various predictive models and sample ratios as a preliminary step in soil organic matter prediction.展开更多
The effects of regulated deficit irrigation(RDI)on the performance of almond cv.Tuono,peach cv.JH-Hall and plum cv.Stanley were assessed on the Saiss Plain(NW,Morocco)over three consecutive growing seasons(2011–2013)...The effects of regulated deficit irrigation(RDI)on the performance of almond cv.Tuono,peach cv.JH-Hall and plum cv.Stanley were assessed on the Saiss Plain(NW,Morocco)over three consecutive growing seasons(2011–2013).Irrigation treatments consisted of a control,irrigation applied to fully satisfy crop water requirements(100%ETC),and two RDI treatments,irrigation applied to 75%ETC(RDI-75)and 50%ETC(RDI-50).These three treatments were applied during fruitgrowth slowdown periods corresponding to Stages II and III in almond and Stage II in peach and plum.Yield and fruit quality traits were determined.The effect of RDI differed between species.Yield and fruit size were reduced significantly only in peach under RDI-50.Fruit quality improved in this species in the first year of the experiment,with an increase of sugar/acid ratio and polyphenol content.Plum quality also improved but the effects were significant only in the second and third years.Similar results were recorded in almond kernel,but their epidermal grooves were deeper under RDI-50,and this may have affected their commercial value.It is concluded that water can be saved during the fruitgrowth slowdown period by up to 25%in peach and 50%in almond and plum with improvements in fruit quality without affecting total yield.展开更多
Background:Mapping of soil nutrients using different covariates was carried out in northern Morocco.This study was undertaken in response to the region’s urgent requirement for an updated soil map.It aimed to test va...Background:Mapping of soil nutrients using different covariates was carried out in northern Morocco.This study was undertaken in response to the region’s urgent requirement for an updated soil map.It aimed to test various covariates combinations for predicting the variability in soil properties using ordinary kriging and kriging with external drift.Methods:A total of 1819 soil samples were collected at a depth of 0–40 cm using the 1-km grid sampling method.Samples were screened for their pH,soil organic matter(SOM),potassium(K_(2)O),and phosphorus(P_(2)O_(5))using standard laboratory protocols.Terrain attributes(T)computed using a 30-m resolution digital elevation model,bioclimatic data(C),and vegetation indices(V)were used as covariates in the study.Each targeted soil property was modeled using covariates separately and then combined(e.g.,pH~T,pH~C,pH~V,and pH~T+C+V).k=tenfold cross-validation was applied to examine the performance of each employed model.The statistical parameter RMSE was used to determine the accuracy of different models.Results:The pH of the area is slightly above the neutral level with a corresponding 7.82%of SOM,290.34 ppm of K_(2)O,and 100.86 ppm of P_(2)O_(5).This was used for all the selected targeted soil properties.As a result,the studied soil properties showed a linear relationship with the selected covariates.pH,SOM,and K 2O presented a moderate spatial autocorrelation,while P2O5 revealed a strong autocorrelation.The cross-validation result revealed that soil pH(RMSE=0.281)and SOM(RMSE=9.505%)were best predicted by climatic variables.P_(2)O_(5)(RMSE=106.511 ppm)produced the best maps with climate,while K_(2)O(RMSE=209.764 ppm)yielded the best map with terrain attributes.Conclusions:The findings suggest that a combination of too many environmental covariates might not provide the actual variability of a targeted soil property.This demonstrates that specific covariates with close relationships with certain soil properties might perform better than the compilation of different environmental covariates,introducing errors due to randomness.In brief,the approach of the present study is new and can be inspiring to decision-makers in the region and other world areas as well.展开更多
Vibrational spectroscopy analysis of full-ripened fig fruits(Ficus carica L.)was acquired using Fourier-transformed infrared(FTIR)spectroscopy by attenuated total reflectance(ATR).The objective of this study was to in...Vibrational spectroscopy analysis of full-ripened fig fruits(Ficus carica L.)was acquired using Fourier-transformed infrared(FTIR)spectroscopy by attenuated total reflectance(ATR).The objective of this study was to investigate accurate discrimination of 25 fig cultivars using chemometric analysis of both ATR-FTIR fingerprinting and in-vitro antioxidant activity along with chromatic coordinates color.In-vitro antioxidant activity was assessed through three methods and displayed statistically significant differences across cultivars and between the fruit parts,with promising antioxidant potency.Infrared spectra were measured separately on both peels and pulp to better know which fruit part provides high discrimination throughput between cultivars.The results showed vibration intensities of five fingerprint regions displaying statically significant differences.The highest vibration intensity occurred in the region of 1175-940 cm^(-1)including the phenols fingerprint.Principal components analysis based on integrated intensities corresponding to fingerprint regions,revealed two main groups in pulp samples,while five groups in peels samples.The pulp extracts of’Nabout’showed a typical vibration in 3000-2800 cm^(-1)and 1775-1725 cm^(-1)regions and,therefore was classified as single subset in cultivars scatterplot.This cultivar had a lightcolored fig and exhibited the highest antioxidant potency for all essays particularly in peel extracts.The biochemical assessment and FTIR fingerprinting data were involved in PCA analysis,and that displayed some dissimilarities in the classification patterns,given the fact that antioxidant activities and chromaticity together could not totally explain the classification based on FTIR fingerprinting between peel and pulp.Application of FTIR-ATR spectroscopy to discriminate fig cultivars seems to be a rapid,accurate and cost-effective alternative to laborious measurement techniques,in fig quality screening and preselection,such as chromatography analysis.This study suggests the use of fig peels for a high-level discrimination while using ATR-FTIR spectroscopy,since it provides high-throughput screening framework.展开更多
文摘This study was carried out to assess plasticity to drought of 30 adult fig cultivars,based on a screening of leaf structural and functional traits under sustained deficit irrigation,corresponding to 60%of crop evapotranspiration.All trees,three per cultivar,are planted in an ex-situ collection in Sais plain,northern Morocco.The measurements concerned leaf area,blade thickness,trichomes density,trichome hair length,stomatal density,stomatal dimensions,stomatal area index,chlorophyll concentration index,relative water content,stomatal conductance,leaf temperature,water loss in detached leaves,cuticular wax content,proline content,total phenolic compounds,and total soluble sugars.The ranking of cultivars regarding drought tolerance was established based on a two-level clustering approach,primarily relying on chlorophyll concentration index and secondarily on water status traits.Results showed significant genotypic variations for all measured traits,except phenolic compounds content.Correlations between structural and functional traits have pinpointed blade thickness and trichome hair length as the key indicators of fig drought tolerance,owing to their involvement in maintaining chlorophyll content under water stress conditions.The extent of the variations shows that fig leaf is endowed with a wide structural and functional diversity,which can give to the species potential for resilience to various environmental stresses,including drought.Among the cultivars assessed,two exotic varieties,“Kadota”and“Royal Blanck”,as well as four local cultivars,namely,“Ferqouch Jmel”,“El Qoti Labied”,“Hamra”and“Fassi”showed the highest drought plasticity level.
文摘Water restrictions management for fruit rosaceous during slowdown periods of fruit growth can increase water use efficiency and improve fruit quality without reducing significantly their yield. In this context, two water restriction levels were tested during four consecutive seasons (2007-2011) in peach, plum and almond trees during slowdown periods of fruit growth corresponding to stage II for peach and plum and to stages II and III for almond. Water was applied by drip irrigation to produce different water-application treatments of 50% ETc (T50) and 75% ETc (T75) of non-stressed trees irrigated at 100% ETc (T100). The response of trees is presented only for the last season of the experiment (2010-2011) where the effect of the applied water stress is more pronounced. Results show that the effect of water restrictions varied depending on the species. Yield and fruit size were reduced significantly for peach only under treatment T50. Fruit quality was improved for this species with an increase of brix refractometric index and a decrease of acidity. These parameters were evolved in the same manner for plum but the observed differences were not significant. For almond, kernel quality remained unaffected by water restriction at T75. However, the epidermal wrinkles of kernels were more embossed, in response to treatment T50, which affected their appearance. Except leaf area, the evolution of shoots growth, chlorophyll content and leaf temperature showed that the physiology of all species was affected by water stress created by the application of the two irrigation treatments but without profound influence, particularly in plum. In conclusion, irrigation-water may be economized during slowdown periods of fruit growth without major negative effect up to 25% ETc for peach and almond and up to 50% ETc for plum.
基金the support from the Ministry of Education,Youth and Sports of the Czech Republic(project No.CZ.02.1.01/0.0/0.0/16_019/0000845)is also acknowledged.
文摘This study was performed to examine the separate and simultaneous influence of predictive models’choice alongside sample ratios selection in soil organic matter(SOM).The research was carried out in northern Morocco,characterized by relatively cold weather and diverse geological conditions.The dataset herein used accounted for 1591 soil samples,which were randomly split into the following ratios:10%(∼150 sample ratio),20%(∼250 sample ratio),35%(∼450 sample ratio),50%(∼600 sample ratio)and 95%(∼1200 sample ratio).Models herein involved were ordinary kriging(OK),regression kriging(RK),multiple linear regression(MLR),random forest(RF),quantile regression forest(QRF),Gaussian process regression(GPR)and an ensemble model.The findings in the study showed that the accuracy of SOM prediction is sensitive to both predictive models and sample ratios.OK combined with 95%sample ratio performed equally to RF in conjunction with all the sample ratios,as the latter did not show much sensitivity to sample ratios.ANOVA results revealed that RF with a∼10%sample ratio could also be optimum for predicting SOM in the study area.In conclusion,the findings herein reported could be instrumental for producing cost-effective detailed and accurate spatial estimation of SOM in other sites.Furthermore,they could serve as a baseline study for future research in the region or elsewhere.Therefore,we recommend conducting series of simulation of all possible combinations between various predictive models and sample ratios as a preliminary step in soil organic matter prediction.
文摘The effects of regulated deficit irrigation(RDI)on the performance of almond cv.Tuono,peach cv.JH-Hall and plum cv.Stanley were assessed on the Saiss Plain(NW,Morocco)over three consecutive growing seasons(2011–2013).Irrigation treatments consisted of a control,irrigation applied to fully satisfy crop water requirements(100%ETC),and two RDI treatments,irrigation applied to 75%ETC(RDI-75)and 50%ETC(RDI-50).These three treatments were applied during fruitgrowth slowdown periods corresponding to Stages II and III in almond and Stage II in peach and plum.Yield and fruit quality traits were determined.The effect of RDI differed between species.Yield and fruit size were reduced significantly only in peach under RDI-50.Fruit quality improved in this species in the first year of the experiment,with an increase of sugar/acid ratio and polyphenol content.Plum quality also improved but the effects were significant only in the second and third years.Similar results were recorded in almond kernel,but their epidermal grooves were deeper under RDI-50,and this may have affected their commercial value.It is concluded that water can be saved during the fruitgrowth slowdown period by up to 25%in peach and 50%in almond and plum with improvements in fruit quality without affecting total yield.
基金This study was supported by an internal Ph.D.grant no.SV20-5-21130 of the Faculty of Agrobiology,Food and Natural Resources of the Czech University of Life Sciences Prague(CZU)And also,NutRisk grant:European Regional Development Fund,project Center for the investigation of synthesis and transformation of nutritional substances in the food chain in interaction with potentially harmful substances of anthropogenic origin:comprehensive assessment of soil contamination risks for the quality of agricultural products,number CZ.02.1.01/0.0/0.0/16_019/0000845.
文摘Background:Mapping of soil nutrients using different covariates was carried out in northern Morocco.This study was undertaken in response to the region’s urgent requirement for an updated soil map.It aimed to test various covariates combinations for predicting the variability in soil properties using ordinary kriging and kriging with external drift.Methods:A total of 1819 soil samples were collected at a depth of 0–40 cm using the 1-km grid sampling method.Samples were screened for their pH,soil organic matter(SOM),potassium(K_(2)O),and phosphorus(P_(2)O_(5))using standard laboratory protocols.Terrain attributes(T)computed using a 30-m resolution digital elevation model,bioclimatic data(C),and vegetation indices(V)were used as covariates in the study.Each targeted soil property was modeled using covariates separately and then combined(e.g.,pH~T,pH~C,pH~V,and pH~T+C+V).k=tenfold cross-validation was applied to examine the performance of each employed model.The statistical parameter RMSE was used to determine the accuracy of different models.Results:The pH of the area is slightly above the neutral level with a corresponding 7.82%of SOM,290.34 ppm of K_(2)O,and 100.86 ppm of P_(2)O_(5).This was used for all the selected targeted soil properties.As a result,the studied soil properties showed a linear relationship with the selected covariates.pH,SOM,and K 2O presented a moderate spatial autocorrelation,while P2O5 revealed a strong autocorrelation.The cross-validation result revealed that soil pH(RMSE=0.281)and SOM(RMSE=9.505%)were best predicted by climatic variables.P_(2)O_(5)(RMSE=106.511 ppm)produced the best maps with climate,while K_(2)O(RMSE=209.764 ppm)yielded the best map with terrain attributes.Conclusions:The findings suggest that a combination of too many environmental covariates might not provide the actual variability of a targeted soil property.This demonstrates that specific covariates with close relationships with certain soil properties might perform better than the compilation of different environmental covariates,introducing errors due to randomness.In brief,the approach of the present study is new and can be inspiring to decision-makers in the region and other world areas as well.
文摘Vibrational spectroscopy analysis of full-ripened fig fruits(Ficus carica L.)was acquired using Fourier-transformed infrared(FTIR)spectroscopy by attenuated total reflectance(ATR).The objective of this study was to investigate accurate discrimination of 25 fig cultivars using chemometric analysis of both ATR-FTIR fingerprinting and in-vitro antioxidant activity along with chromatic coordinates color.In-vitro antioxidant activity was assessed through three methods and displayed statistically significant differences across cultivars and between the fruit parts,with promising antioxidant potency.Infrared spectra were measured separately on both peels and pulp to better know which fruit part provides high discrimination throughput between cultivars.The results showed vibration intensities of five fingerprint regions displaying statically significant differences.The highest vibration intensity occurred in the region of 1175-940 cm^(-1)including the phenols fingerprint.Principal components analysis based on integrated intensities corresponding to fingerprint regions,revealed two main groups in pulp samples,while five groups in peels samples.The pulp extracts of’Nabout’showed a typical vibration in 3000-2800 cm^(-1)and 1775-1725 cm^(-1)regions and,therefore was classified as single subset in cultivars scatterplot.This cultivar had a lightcolored fig and exhibited the highest antioxidant potency for all essays particularly in peel extracts.The biochemical assessment and FTIR fingerprinting data were involved in PCA analysis,and that displayed some dissimilarities in the classification patterns,given the fact that antioxidant activities and chromaticity together could not totally explain the classification based on FTIR fingerprinting between peel and pulp.Application of FTIR-ATR spectroscopy to discriminate fig cultivars seems to be a rapid,accurate and cost-effective alternative to laborious measurement techniques,in fig quality screening and preselection,such as chromatography analysis.This study suggests the use of fig peels for a high-level discrimination while using ATR-FTIR spectroscopy,since it provides high-throughput screening framework.
