Interpretation of primary growth markers (modules) is neglected in sustainable resource management processes, yet it opens up prospects for long time series on tree crown development, necessary for their characterizat...Interpretation of primary growth markers (modules) is neglected in sustainable resource management processes, yet it opens up prospects for long time series on tree crown development, necessary for their characterization in the current context of climate change. This study aimed to assess the morphological variation of crown shoots in <i><span style="font-family:Verdana;">Parkia biglobosa</span></i><span style="font-family:Verdana;"> in the face of a changing environment. Axis growth modules of 420 individuals of different ages were retrospectively analyzed in the presence or absence of shading during the wet and dry seasons in seven localities in Cote d’Ivoire. The results showed that the developmental environment of individuals did not influence the growth modules dimensions (P > 0.05). However, module size remained significantly different between locations (P < 0.05). The southern part of the gradient is still favourable and has priority for the establishment of permanent plots. The modules morphology differs from the youngest to the oldest individuals (P < 0.05). The rainy season remains the ideal period for the implementation of agroforestry reforestation programmes based on this species (P < 0.05). </span><i><span style="font-family:Verdana;">Parkia biglobosa</span></i><span style="font-family:Verdana;"> is a monochasial sympod (Pseudo-monopod) with a relay axis that follows the Paul Champagnat architectural model in the young stage, and transits to the Wilhelm Troll model later in the adult and old stage. This information contributes to the understanding of the functioning of crown and the adaptation of this species to a varying environment. It could guide choice of suitable environment and ideal genotype for the implementation of a reforestation or agroforestry programme based on </span><i><span style="font-family:Verdana;">Parkia biglobosa</span></i><span style="font-family:Verdana;">.</span>展开更多
The rapid rate of deforestation in Cote d’Ivoire has led to loss of plant species diversity and also threatens some commercial tree species with extinction.Some reforestation and aff orestation has been completed.How...The rapid rate of deforestation in Cote d’Ivoire has led to loss of plant species diversity and also threatens some commercial tree species with extinction.Some reforestation and aff orestation has been completed.However,for some species,the numbers of surviving transplants has declined.Hence,it is necessary to develop properly adapted and resilient genotypes that can eff ectively support the programs of forest restoration.In this context we evaluated the eff ects of the provenances of seeds and of various treatments on the germination rates and on plant growth of four commercial trees species(Pycnanthus angolensis,Terminalia superba,Mansonia altissima and Pterygota macrocarpa).We analyzed these parameters for seeds of three provenances(Daloa,Akoupéand Daoukro)of four species and for thirty plants aged 6 months per provenance.Time to begin germination and time to reach maximum germination were similar among species,and were not infl uenced by either treatment or provenance.Untreated seeds and those soaked for 24 and 48 h in water at room temperature yielded the highest germination rates,irrespective of species or provenance.The one exception was P.angolensis,for which no germination was recorded.Within species,some provenances produced higher germination percentages than did others.No clear relationship was computed between the germination rate and the morphometric characteristics of the seeds which varied signifi cantly between provenances.Plant growth and morphological variability also depended greatly on provenance.Genetic factors might be implicated,therefore provenance trials should be undertaken and evaluated.Furthermore,molecular analysis should be undertaken to confi rm the implications of genetic factors and allow for genetic selection.展开更多
<i>Khaya senegalensis</i><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> is one of the largest and most majestic ...<i>Khaya senegalensis</i><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> is one of the largest and most majestic trees in Africa. Overexploited for its precious wood and medicinal values, the natural stands of this species are in danger of extinction in Cote d’Ivoire. Its sustainable management through regeneration techniques and assessment of its degree of adaptation to the changing climate is necessary. </span><span style="font-family:Verdana;">The aim of this study is</span><span style="font-family:Verdana;"> to evaluate the effect of different environments on seedling germination and development in </span><span style="font-family:Verdana;"><i>Khaya senegalensis</i></span><span style="font-family:Verdana;">. A total of 2160 seeds from different mother plants and 540 individuals from seed germination were selected and evaluated. The trials were conducted on three sites that were distinct by their microclimate (two nurseries in Cote d’Ivoire and one greenhouse in France). Analysis of variance showed that germination and morphology parameters were not influenced by the characteristics of the mother plants used (p > 0.05), but rather by the study sites (P < 0.05). The stable and controlled greenhouse climate was more advantageous for latency time (12.66 ± 0.80 days), germination delay (16.96 96 ± 0.54 days), germination speed (19.66 ± 2.95 days), germination duration (10.83 ± 2.27 days) and germination rate (88.88 ± 7.97) with more vigorous sowing than the other two sites. The results showed in general that the higher the height of the seedlings, the thicker the diameter of the seedlings (r = 0.796) and the higher the number of leaves (r = 0.946). This savannah species is native to the arid zones of Africa, but this study highlighted its adaptive potential to changing and different climates. These results are decision support tools for the regeneration of native pioneer forest species with high agroforestry potential and socio-economic importance such as </span><span style="font-family:Verdana;"><i>Khaya senegalensis</i></span><span style="font-family:Verdana;">. This study could be extended to other species </span><span style="font-family:Verdana;">in order to</span><span style="font-family:Verdana;"> restore disturbed ecosystems.</span></span></span></span>展开更多
The present study was carried out to verify the statistical relationships between the characteristic parameters in terms of vegetative aerial architecture of the date palms for simulating realistic 3D models. The vege...The present study was carried out to verify the statistical relationships between the characteristic parameters in terms of vegetative aerial architecture of the date palms for simulating realistic 3D models. The vegetal material was composed of two Tunisian varieties of Phoenix dactylifera L., ＂Barhi＂ and ＂Rochdi＂. The observations are taken place in Gabes and on one pair of palms per main stem and offshoot for each cultivar. The analysis of the characteristic dimensions of the pinnae and rachis allowed the determination of a minimum sample. The geometrical analysis confirmed the existence of a strong correlation between rotation angles and radial angles. The architectural analysis of the two Tunisian cultivars revealed that the distribution of characteristic parameter values of pinnae was the outcome ofa regionalized variable along the rachis. This statistical study of relationships between the characteristic parameters in terms of vegetative aerial architecture of the two varieties allows executing a new measurement protocol for computing and simulating realistic 3D models.展开更多
The date palm (Phoenix dactylifera L.), a dioecious species, is of particular interest in the Sahel due to its phenological plasticity in relation to climate change and its double-flowering capacity. This article expl...The date palm (Phoenix dactylifera L.), a dioecious species, is of particular interest in the Sahel due to its phenological plasticity in relation to climate change and its double-flowering capacity. This article explores local practices and knowledge associated with date palm cultivation in the oasis basins of southeastern Niger, and provides an inventory of local seed propagated varieties, for more effectively guiding agricultural research and the breeding of this species. We carried out a survey of 30 date palm growers in 14 villages of the Manga region. The qualitative data of the survey were processed by a Multiple Correspondence Analysis. We inventoried 19 date palm varieties, for which the main distinctive criterion was fruit colour, but some other criteria such as biology or provenance were also used. The cultural practices and knowledge associated with the date palm in Manga have improved since the 1990s. They also depend on ethnic groups and the importance they assign to farming compared to livestock rearing and trading activities. The type of basin (high, intermediate, or low water table) influences growers’ practices and perceptions. Lastly, the date harvest in the wet season is abundant, but of mediocre quality, whereas it is the opposite for the dry season harvest. To conclude, sustainable development of date palm cultivation in the Sahel zone relies firstly on the selection of varieties that are early fruit producers or that can complete fruit maturation during the raining season and secondly on technical capacity building for producers.展开更多
Aims One critical challenge for plants is to maintain an adequate nutrient supply under fluctuating environmental conditions.This is particularly true for epiphytic species that have limited or no access to the pedosp...Aims One critical challenge for plants is to maintain an adequate nutrient supply under fluctuating environmental conditions.This is particularly true for epiphytic species that have limited or no access to the pedosphere and often live in harsh climates.Bromeliads have evolved key innovations such as epiphytism,water-absorbing leaf trichomes,tank habit and Crassulacean acid metabolism(CAM)photosynthesis that enable them to survive under various environmental conditions.Bromeliads encompass diverse ecological types that live on different substrates(they can be terrestrial,epilithic or epiphytic)and vary in their ability to retain water(they can be tank-forming or tankless)and photosynthetic pathway(i.e.C3 or CAM).In this review,we outline the nutritional modes and specializations that enable bromeliads to thrive in a wide range of nutrient-poor(mostly nitrogen-depleted)environments.Important FindingsBromeliads have evolved a great diversity of morphologies and functional adaptations leading to the existence of numerous nutritional modes.Focusing on species that have absorptive foliar trichomes,we review evidence that bromeliads have evolved multi-faceted nutritional strategies to respond to fluctuations in the supply of natural nitrogen(N).These plants have developed mutualistic associations with many different and functionally diverse terrestrial and aquatic microorganisms and metazoans that contribute substantially to their mineral nutrition and,thus,their fitness and survival.Bacterial and fungal microbiota-assisted N provisioning,protocarnivory,digestive mutualisms and myrmecotrophic pathways are the main strategies used by bromeliads to acquire nitrogen.The combination of different nutritional pathways in bromeliads represents an important adaptation enabling them to exploit nutrient-poor habitats.Nonetheless,as has been shown for several other vascular plants,multiple partners are involved in nutrient acquisition indicating that there have been convergent adaptations to nutrient scarcity.Finally,we point out some gaps in the current knowledge of bromeliad nutrition that offer fascinating research opportunities.展开更多
The cultivation of seed mixtures for local pastures is a traditional mixed cropping technique of cereals and legumes for producing,at a low production cost,a balanced animal feed in energy and protein in livestock sys...The cultivation of seed mixtures for local pastures is a traditional mixed cropping technique of cereals and legumes for producing,at a low production cost,a balanced animal feed in energy and protein in livestock systems.By considerably improving the autonomy and safety of agricultural systems,as well as reducing their impact on the environment,it is a type of crop that responds favorably to both the evolution of the European regulations on the use of phytosanitary products and the expectations of consumers who wish to increase their consumption of organic products.However,farmers find it difficult to adopt it because cereals and legumes do not ripen synchronously and the harvested seeds are heterogeneous,making it more difficult to assess their nutritional value.Many efforts therefore remain to be made to acquire and aggregate technical and economical references to evaluate to what extent the cultivation of seed mixtures could positively contribute to securing and reducing the costs of herd feeding.The work presented in this paper proposes new Artificial Intelligence techniques that could be transferred to an online or smartphone application to automatically estimate the nutritional value of harvested seed mixes to help farmers better manage the yield and thus engage them to promote and contribute to a better knowledge of this type of cultivation.For this purpose,an original open image dataset has been built containing 4,749 images of seed mixes,covering 11 seed varieties,with which 2 types of recent deep learning models have been trained.The results highlight the potential of this method and show that the best-performing model is a recent state-of-the-art vision transformer pre-trained with self-supervision(Bidirectional Encoder representation from Image Transformer).It allows an estimation of the nutritional value of seed mixtures with a coefficient of determination R^(2)score of 0.91,which demonstrates the interest of this type of approach,for its possible use on a large scale.展开更多
文摘Interpretation of primary growth markers (modules) is neglected in sustainable resource management processes, yet it opens up prospects for long time series on tree crown development, necessary for their characterization in the current context of climate change. This study aimed to assess the morphological variation of crown shoots in <i><span style="font-family:Verdana;">Parkia biglobosa</span></i><span style="font-family:Verdana;"> in the face of a changing environment. Axis growth modules of 420 individuals of different ages were retrospectively analyzed in the presence or absence of shading during the wet and dry seasons in seven localities in Cote d’Ivoire. The results showed that the developmental environment of individuals did not influence the growth modules dimensions (P > 0.05). However, module size remained significantly different between locations (P < 0.05). The southern part of the gradient is still favourable and has priority for the establishment of permanent plots. The modules morphology differs from the youngest to the oldest individuals (P < 0.05). The rainy season remains the ideal period for the implementation of agroforestry reforestation programmes based on this species (P < 0.05). </span><i><span style="font-family:Verdana;">Parkia biglobosa</span></i><span style="font-family:Verdana;"> is a monochasial sympod (Pseudo-monopod) with a relay axis that follows the Paul Champagnat architectural model in the young stage, and transits to the Wilhelm Troll model later in the adult and old stage. This information contributes to the understanding of the functioning of crown and the adaptation of this species to a varying environment. It could guide choice of suitable environment and ideal genotype for the implementation of a reforestation or agroforestry programme based on </span><i><span style="font-family:Verdana;">Parkia biglobosa</span></i><span style="font-family:Verdana;">.</span>
文摘The rapid rate of deforestation in Cote d’Ivoire has led to loss of plant species diversity and also threatens some commercial tree species with extinction.Some reforestation and aff orestation has been completed.However,for some species,the numbers of surviving transplants has declined.Hence,it is necessary to develop properly adapted and resilient genotypes that can eff ectively support the programs of forest restoration.In this context we evaluated the eff ects of the provenances of seeds and of various treatments on the germination rates and on plant growth of four commercial trees species(Pycnanthus angolensis,Terminalia superba,Mansonia altissima and Pterygota macrocarpa).We analyzed these parameters for seeds of three provenances(Daloa,Akoupéand Daoukro)of four species and for thirty plants aged 6 months per provenance.Time to begin germination and time to reach maximum germination were similar among species,and were not infl uenced by either treatment or provenance.Untreated seeds and those soaked for 24 and 48 h in water at room temperature yielded the highest germination rates,irrespective of species or provenance.The one exception was P.angolensis,for which no germination was recorded.Within species,some provenances produced higher germination percentages than did others.No clear relationship was computed between the germination rate and the morphometric characteristics of the seeds which varied signifi cantly between provenances.Plant growth and morphological variability also depended greatly on provenance.Genetic factors might be implicated,therefore provenance trials should be undertaken and evaluated.Furthermore,molecular analysis should be undertaken to confi rm the implications of genetic factors and allow for genetic selection.
文摘<i>Khaya senegalensis</i><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> is one of the largest and most majestic trees in Africa. Overexploited for its precious wood and medicinal values, the natural stands of this species are in danger of extinction in Cote d’Ivoire. Its sustainable management through regeneration techniques and assessment of its degree of adaptation to the changing climate is necessary. </span><span style="font-family:Verdana;">The aim of this study is</span><span style="font-family:Verdana;"> to evaluate the effect of different environments on seedling germination and development in </span><span style="font-family:Verdana;"><i>Khaya senegalensis</i></span><span style="font-family:Verdana;">. A total of 2160 seeds from different mother plants and 540 individuals from seed germination were selected and evaluated. The trials were conducted on three sites that were distinct by their microclimate (two nurseries in Cote d’Ivoire and one greenhouse in France). Analysis of variance showed that germination and morphology parameters were not influenced by the characteristics of the mother plants used (p > 0.05), but rather by the study sites (P < 0.05). The stable and controlled greenhouse climate was more advantageous for latency time (12.66 ± 0.80 days), germination delay (16.96 96 ± 0.54 days), germination speed (19.66 ± 2.95 days), germination duration (10.83 ± 2.27 days) and germination rate (88.88 ± 7.97) with more vigorous sowing than the other two sites. The results showed in general that the higher the height of the seedlings, the thicker the diameter of the seedlings (r = 0.796) and the higher the number of leaves (r = 0.946). This savannah species is native to the arid zones of Africa, but this study highlighted its adaptive potential to changing and different climates. These results are decision support tools for the regeneration of native pioneer forest species with high agroforestry potential and socio-economic importance such as </span><span style="font-family:Verdana;"><i>Khaya senegalensis</i></span><span style="font-family:Verdana;">. This study could be extended to other species </span><span style="font-family:Verdana;">in order to</span><span style="font-family:Verdana;"> restore disturbed ecosystems.</span></span></span></span>
文摘The present study was carried out to verify the statistical relationships between the characteristic parameters in terms of vegetative aerial architecture of the date palms for simulating realistic 3D models. The vegetal material was composed of two Tunisian varieties of Phoenix dactylifera L., ＂Barhi＂ and ＂Rochdi＂. The observations are taken place in Gabes and on one pair of palms per main stem and offshoot for each cultivar. The analysis of the characteristic dimensions of the pinnae and rachis allowed the determination of a minimum sample. The geometrical analysis confirmed the existence of a strong correlation between rotation angles and radial angles. The architectural analysis of the two Tunisian cultivars revealed that the distribution of characteristic parameter values of pinnae was the outcome ofa regionalized variable along the rachis. This statistical study of relationships between the characteristic parameters in terms of vegetative aerial architecture of the two varieties allows executing a new measurement protocol for computing and simulating realistic 3D models.
文摘The date palm (Phoenix dactylifera L.), a dioecious species, is of particular interest in the Sahel due to its phenological plasticity in relation to climate change and its double-flowering capacity. This article explores local practices and knowledge associated with date palm cultivation in the oasis basins of southeastern Niger, and provides an inventory of local seed propagated varieties, for more effectively guiding agricultural research and the breeding of this species. We carried out a survey of 30 date palm growers in 14 villages of the Manga region. The qualitative data of the survey were processed by a Multiple Correspondence Analysis. We inventoried 19 date palm varieties, for which the main distinctive criterion was fruit colour, but some other criteria such as biology or provenance were also used. The cultural practices and knowledge associated with the date palm in Manga have improved since the 1990s. They also depend on ethnic groups and the importance they assign to farming compared to livestock rearing and trading activities. The type of basin (high, intermediate, or low water table) influences growers’ practices and perceptions. Lastly, the date harvest in the wet season is abundant, but of mediocre quality, whereas it is the opposite for the dry season harvest. To conclude, sustainable development of date palm cultivation in the Sahel zone relies firstly on the selection of varieties that are early fruit producers or that can complete fruit maturation during the raining season and secondly on technical capacity building for producers.
基金support from the Programme Convergence 2007-2013,Région Guyane from the European community(BREGA,ref.32080)an‘Investissement d’Avenir’grant managed by Agence Nationale de la Recherche(CEBA,ref.ANR-10-LABX-0025).
文摘Aims One critical challenge for plants is to maintain an adequate nutrient supply under fluctuating environmental conditions.This is particularly true for epiphytic species that have limited or no access to the pedosphere and often live in harsh climates.Bromeliads have evolved key innovations such as epiphytism,water-absorbing leaf trichomes,tank habit and Crassulacean acid metabolism(CAM)photosynthesis that enable them to survive under various environmental conditions.Bromeliads encompass diverse ecological types that live on different substrates(they can be terrestrial,epilithic or epiphytic)and vary in their ability to retain water(they can be tank-forming or tankless)and photosynthetic pathway(i.e.C3 or CAM).In this review,we outline the nutritional modes and specializations that enable bromeliads to thrive in a wide range of nutrient-poor(mostly nitrogen-depleted)environments.Important FindingsBromeliads have evolved a great diversity of morphologies and functional adaptations leading to the existence of numerous nutritional modes.Focusing on species that have absorptive foliar trichomes,we review evidence that bromeliads have evolved multi-faceted nutritional strategies to respond to fluctuations in the supply of natural nitrogen(N).These plants have developed mutualistic associations with many different and functionally diverse terrestrial and aquatic microorganisms and metazoans that contribute substantially to their mineral nutrition and,thus,their fitness and survival.Bacterial and fungal microbiota-assisted N provisioning,protocarnivory,digestive mutualisms and myrmecotrophic pathways are the main strategies used by bromeliads to acquire nitrogen.The combination of different nutritional pathways in bromeliads represents an important adaptation enabling them to exploit nutrient-poor habitats.Nonetheless,as has been shown for several other vascular plants,multiple partners are involved in nutrient acquisition indicating that there have been convergent adaptations to nutrient scarcity.Finally,we point out some gaps in the current knowledge of bromeliad nutrition that offer fascinating research opportunities.
基金This research work was mainly undertaken within the framework of the Carpeso project(AAPIP 2019 n°19AIP5902),supported by the CASDAR program(The Special Affection Account for Agricultural and Rural Development)funded by the French National Research Agency(ANR)through the grant PI@ntAgroEco 22-PEAE0009.
文摘The cultivation of seed mixtures for local pastures is a traditional mixed cropping technique of cereals and legumes for producing,at a low production cost,a balanced animal feed in energy and protein in livestock systems.By considerably improving the autonomy and safety of agricultural systems,as well as reducing their impact on the environment,it is a type of crop that responds favorably to both the evolution of the European regulations on the use of phytosanitary products and the expectations of consumers who wish to increase their consumption of organic products.However,farmers find it difficult to adopt it because cereals and legumes do not ripen synchronously and the harvested seeds are heterogeneous,making it more difficult to assess their nutritional value.Many efforts therefore remain to be made to acquire and aggregate technical and economical references to evaluate to what extent the cultivation of seed mixtures could positively contribute to securing and reducing the costs of herd feeding.The work presented in this paper proposes new Artificial Intelligence techniques that could be transferred to an online or smartphone application to automatically estimate the nutritional value of harvested seed mixes to help farmers better manage the yield and thus engage them to promote and contribute to a better knowledge of this type of cultivation.For this purpose,an original open image dataset has been built containing 4,749 images of seed mixes,covering 11 seed varieties,with which 2 types of recent deep learning models have been trained.The results highlight the potential of this method and show that the best-performing model is a recent state-of-the-art vision transformer pre-trained with self-supervision(Bidirectional Encoder representation from Image Transformer).It allows an estimation of the nutritional value of seed mixtures with a coefficient of determination R^(2)score of 0.91,which demonstrates the interest of this type of approach,for its possible use on a large scale.
