RESUMO
Traditional pastures in temperate regions face limitations such as reduced growth and nutritional quality during the summer season. Plantain (P. lanceolata L.) offers advantages like increased yield and decreased nitrogen losses from grazing ruminants. Effective grazing management is essential for pasture health, and defoliation frequency and intensity play a pivotal role. This study aimed to evaluate plantain's regrowth, yield, and morpho-physiological and chemical responses under different defoliation frequencies and intensities, with the goal of enhancing its management in pastures. The study was conducted in pots within a controlled-environment growth chamber, examining the impact of three defoliation frequencies (based on extended leaf length: 15, 25 and 35 cm) and two defoliation intensities (5 and 8 cm of residual heights) with four replicates (24 pots as experimental units). The variables of interest were morphological characteristics, dry matter (DM) accumulation, herbage chemical composition, growth rate traits, and photosynthetic parameters. Defoliation frequency affected plantain's growth and nutritional composition. More frequent cuts (15 cm) resulted in lower DM yield per cut and lower stem content, while less frequent cuts (35 cm) produced higher values. Defoliation intensity influenced the proportion of leaves and stems in the total DM, with 5 cm cuts favoring leaves. Nutrient content was also affected by defoliation frequency, with less frequent cuts (35 cm) showing lower crude protein concentration and metabolizable energy content but higher neutral detergent fiber and water-soluble carbohydrate concentration. Plantain's growth rate variables were mainly influenced by defoliation frequency, with less frequent cuts promoting faster leaf appearance and growth of new leaves. The basal fluorescence variables and chlorophyll content were affected by cutting frequency, being highest when cut less frequently (35 cm), while no differences were found in the actual quantum efficiency among different defoliation frequencies and intensities. The fraction of light dedicated to non-photochemical quenching was highest when cut less frequently and more intensively. Overall, defoliation at 25 cm of extended leaf length balanced plantain forage quality and regrowth capacity.
Assuntos
Folhas de Planta , Plantago , Plantago/crescimento & desenvolvimento , Plantago/fisiologia , Plantago/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Fotossíntese , Estações do AnoRESUMO
Withania (Solanaceae, Solanoideae) is a widespread genus. Comparative macro-, micro-morphological, anatomical, and molecular features of this genus in Egypt were examined using light and scanning electron microscopy to reassess the conflicted taxonomic relationships between the two studied species. The most significant morphological differences that have been found were: the shape of the lamina, apex, anther, and stigma, and the ratio of calyx tube/lobe; anatomical examination of taxonomic interest are as follows: number of vascular bundles, presence of ears and distribution of accessory vascular bundles in petiole and shape of spongy cells, and number of lower parenchyma in the midrib region of the leaf; trichomes of both species showed no significant differences; pollen, and seed characters are of taxonomic significance in differentiation and characterization between them. Protein profiling revealed that W. somnifera has only conserved proteins, while W. obtusifolia possessed both conserved and additional proteins in their SDS-PAGE banding patterns. Eleven starts codon-targeted (ScoT) primers were applied and produced 96 amplicons with an average of 70.83% polymorphism/primer. W. obtusifolia generated more polymorphic bands and maintained monomorphic ones. SDS-PAGE disclosed that both Withania species were 50% related. While Scot-Dendrogram revealed that both Withania species were poorly related. So, protein and molecular analyses showed considerable genetic variations between these two species.
Assuntos
Withania , Egito , Withania/genética , Withania/classificação , Withania/metabolismo , Filogenia , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Microscopia Eletrônica de Varredura , Proteínas de Plantas/genéticaRESUMO
KEY MESSAGE: High-throughput next-generation sequencing of 161 olive germplas. 33 samples were selected as core olive germplasm and Fingerprints were constructed. After GWAS analysis of olive leaf shape, 14 candidate genes were localized. Olive (Olea europaea L.) has been introduced to China since the 1960s. After a prolonged period of variation and domestication, there is a lack of comprehensive research on its genetics. The olive oil directly extracted from Olea europaea L. is recognized as 'liquid gold', nevertheless, people constantly overlook the valuable wealth of olive leaves. High-throughput next-generation sequencing was performed on 161 olive germplasm to analyze the kinship, genetic structure and diversity of olives, and the core germplasm of olives were selected and fingerprints were constructed. Meanwhile, Genome-wide association analysis (GWAS) was performed to locate the gene for regulating olive leaf shape. Herein, the results parsed that most of the Chinese olive germplasm was more closely related to the Italian germplasm. A wealth of hybridized germplasm possessed high genetic diversity and had the potential to be used as superior parental material for olive germplasm. A total of 33 samples were selected and characterized as core germplasm of olive and Fingerprints were also constructed. A total of 14 candidate genes were localized after GWAS analysis of four olive leaf shape phenotypes, including leaf shape, leaf curvature shape, leaf tip and leaf base shape. Collectively, this study revealed the genetic basis of olives in China and also succeeded in constructing the core germplasm that stands for the genetic diversity of olives, which can contribute to the scientific and effective collection and preservation of olive germplasm resources, and provide a scientific basis for the in-depth excavation and utilization of genes regulating olive leaf shape.
Assuntos
Estudo de Associação Genômica Ampla , Olea , Folhas de Planta , Olea/genética , Folhas de Planta/genética , Folhas de Planta/anatomia & histologia , Sequenciamento de Nucleotídeos em Larga Escala , Variação Genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Melhoramento Vegetal/métodos , ChinaRESUMO
Leaves play a crucial role as ornamental organs in Spathiphyllum, exhibiting distinct differences across various Spathiphyllum varieties. Leaf development is intricately linked to processes of cell proliferation and expansion, with cell morphology often regulated by plant cell walls, primarily composed of cellulose. Alterations in cellulose content can impact cell morphology, subsequently influencing the overall shape of plant organs. Although cellulases have been shown to affect cellulose levels in plant cells, genetic evidence linking them to the regulation of leaf shape remains limited. This study took the leaves of Spathiphyllum 'Mojo' and its somatic variants as the research objects. We screened four cellulase gene family members from the transcriptome and then measured the leaf cellulose content, cellulase activity, and expression levels of cellulase-related genes. Correlation analysis pinpointed the gene SpGH9A3 as closely associated with leaf shape variations in the mutant. Green fluorescent fusion protein assays revealed that the SpGH9A3 protein was localized to the cell membrane. Notably, the expression of the SpGH9A3 gene in mutant leaves peaked during the early spread stage, resulting in smaller overall leaf size and reduced cellulose content upon overexpression in Arabidopsis.
Assuntos
Arabidopsis , Celulose , Regulação da Expressão Gênica de Plantas , Folhas de Planta , Proteínas de Plantas , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Celulose/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Celulase/genética , Celulase/metabolismoRESUMO
MAIN CONCLUSION: The leaf color asymmetry found in the reciprocal hybrids C. hystrix × C. sativus (HC) and C. sativus × C. hystrix (CH) could be influenced by the CsPPR gene (CsaV3_1G038250.1). Most angiosperm organelles are maternally inherited; thus, the reciprocal hybrids usually exhibit asymmetric phenotypes that are associated with the maternal parent. However, there are two sets of organelle genomes in the plant cytoplasm, and the mechanism of reciprocal differences are more complex and largely unknown, because the chloroplast genes are involved besides mitochondrial genes. Cucumis spp. contains the species, i.e., cucumber and melon, which chloroplasts and mitochondria are maternally inherited and paternally inherited, respectively, serving as good materials for the study of reciprocal differences. In this study, leaf color asymmetry was observed in the reciprocal hybrids (HC and CH) derived from C. sativus (2n = 14, CC) and C. hystrix (2n = 24, HH), where the leaves of HC were found to have reduced chlorophyll content, abnormal chloroplast structure and lower photosynthetic capacity. Transcriptomic analysis revealed that the chloroplast development-related genes were differentially expressed in leaf color asymmetry. Genetic analysis showed that leaf color asymmetry was caused by the maternal chloroplast genome. Comparative analysis of chloroplast genomes revealed that there was no mutation in the chloroplast genome during interspecific hybridization. Moreover, a PPR gene (CsaV3_1G038250.1) with RNA-editing function was found to be involved in the regulation of leaf color asymmetry. These findings provide new insights into the regulatory mechanisms of asymmetric phenotypes in plant reciprocal crosses.
Assuntos
Cloroplastos , Cucumis sativus , Folhas de Planta , Edição de RNA , Cucumis sativus/genética , Cucumis sativus/fisiologia , Cucumis sativus/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Cloroplastos/genética , Edição de RNA/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Hibridização Genética , Fotossíntese/genética , Fenótipo , Clorofila/metabolismoRESUMO
Clematis, one of the largest genera of the family Ranunculaceae, has a wide array of morphological variation and is considered the most difficult group of taxa in terms of infrageneric discrimination. This study assessed the leaf micromorphological features of 19 Clematis taxa (16 species and three varieties) found in Korea. The leaf surface features were studied under scanning electron microscopy, and the stomatal counting and measurement were carried out under light microscopy. Clematis are hypostomatic, meaning the stomata are only found on the abaxial surface of the leaf. Observed taxa showed near uniformity in the epidermal cell type, structure, and morphology on both surfaces of the leaf. Differences were observed in the presence and absence and/or abundance of trichomes on both the adaxial and abaxial surfaces, the epidermal cell boundary, and the periclinal and anticlinal wall of the cells. Differences were also observed in the number of the epidermal cells connected with the stomata on the abaxial surface, with small differences noted in epidermal cell shapes. The ANOVA showed a significant variation in the stomata density in the studied taxa (P < 0.0001). The cluster analysis based on 13 leaf micromorphological features generated four major clusters. These results indicated similarities in certain key leaf micromorphological features among taxa from the Tubulosae, Clematis, and Virona sections. In the genus Clematis, as with other morphological characteristics, using leaf micromorphological characters alone, which possess limited taxonomic value, proves inadequate for resolving infrageneric relationships. However, incorporating certain features with other morphological characteristics offers a possible alternative means of determining the infrageneric relationships within the genus.
Assuntos
Clematis , Microscopia Eletrônica de Varredura , Folhas de Planta , Clematis/anatomia & histologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/ultraestrutura , República da Coreia , Estômatos de Plantas/ultraestrutura , Estômatos de Plantas/anatomia & histologia , Epiderme Vegetal/ultraestrutura , Epiderme Vegetal/anatomia & histologia , Epiderme Vegetal/citologia , Análise por ConglomeradosRESUMO
The water relation strategy is a key issue in climate change. Given the difficulty of determining water relations strategy, there is a need for simple traits with a solid theoretical basis to estimate it. Traits associated with resource allocation patterns along a 'fast-slow' plant economics spectrum are particularly compelling, reflecting trade-offs between growth rate and carbon allocation. Avocado (Persea americana ), fig tree (Ficus carica ), mandarin (Citrus reticulata ), olive (Olea europaea ), pomegranate (Punica granatum ), and grapevine (Vitis vinifera ) were characterised in terms of iso-anisohydric strategy through stomatal behaviour, water potential at the turgor loss point (TLP), and hydroscape area. Additionally, the association of these metrics with leaf mass per area (LMA) and wood density (WDen) was explored. We observed high coordination between LMA and WDen, and both traits were related to metrics of water relation strategy. More anisohydric species tended to invest more carbon per unit leaf area or unit stem volume, which has implications for hydraulic efficiency and water stress tolerance. WDen and TLP were the most powerful traits in estimating the water relation strategy for six fruit species. These traits are easy to measure, time-cost efficient, and appear central to coordinating multiple traits and behaviours along the water relations strategies.
Assuntos
Carbono , Folhas de Planta , Caules de Planta , Árvores , Água , Folhas de Planta/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Água/metabolismo , Carbono/metabolismo , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/fisiologia , Caules de Planta/anatomia & histologia , Árvores/crescimento & desenvolvimento , Árvores/fisiologia , Persea/fisiologia , Persea/crescimento & desenvolvimento , Citrus/crescimento & desenvolvimento , Citrus/fisiologia , Citrus/anatomia & histologia , Frutas/crescimento & desenvolvimento , Vitis/crescimento & desenvolvimento , Vitis/fisiologia , Olea/fisiologia , Olea/crescimento & desenvolvimento , Ficus/fisiologia , Ficus/crescimento & desenvolvimento , Punica granatumRESUMO
KEY MESSAGE: Multi-environmental characterization of flag leaf morphology traits in the US winter wheat revealed nine stable genomic regions for different flag leaf-related traits including a major region governing flag leaf angle. Flag leaf in wheat is the primary contributor to accumulating photosynthetic assimilates. Flag leaf morphology (FLM) traits determine the overall canopy structure and capacity to intercept the light, thus influencing photosynthetic efficiency. Hence, understanding the genetic control of these traits could be useful for breeding desirable ideotypes in wheat. We used a panel of 272 accessions from the hard winter wheat (HWW) region of the USA to investigate the genetic architecture of five FLM traits including flag leaf length (FLL), width (FLW), angle (FLANG), length-width ratio, and area using multilocation field experiments. Multi-environment GWAS using 14,537 single-nucleotide polymorphisms identified 36 marker-trait associations for different traits, with nine being stable across environments. A novel and major stable region for FLANG (qFLANG.1A) was identified on chromosome 1A accounting for 9-13% variation. Analysis of spatial distribution for qFLANG.1A in a set of 2354 breeding lines from the HWW region showed a higher frequency of allele associated with narrow leaf angle. A KASP assay was developed for allelic discrimination of qFLANG.1A and was used for its independent validation in a diverse set of spring wheat accessions. Furthermore, candidate gene analysis for two regions associated with FLANG identified seven putative genes of interest for each of the two regions. The present study enhances our understanding of the genetic control of FLM in wheat, particularly FLANG, and these results will be useful for dissecting the genes underlying canopy architecture in wheat facilitating the development of climate-resilient wheat varieties.
Assuntos
Mapeamento Cromossômico , Fenótipo , Melhoramento Vegetal , Folhas de Planta , Polimorfismo de Nucleotídeo Único , Triticum , Triticum/genética , Triticum/crescimento & desenvolvimento , Triticum/anatomia & histologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Locos de Características Quantitativas , Estudos de Associação Genética , Genótipo , Estados Unidos , Genoma de PlantaRESUMO
Transformation of plants using wild strains of agrobacteria is termed natural transformation and is not covered by GMO legislation in e.g. European Union and Japan. In the current study, offspring lines (A11 and B3) of Rhizobium rhizogenes naturally transformed oilseed rape (Brassica napus) were randomly selected to characterize the morphological traits, and analyze the implications of such morphological changes on plant drought resilience. It was found that the introduction of Ri-genes altered the biomass partitioning to above- and under-ground parts of oilseed rape plants. Compared to the wild type (WT), the A11 and B3 lines exhibited 1.2-4.0 folds lower leaf and stem dry weight, leaf area and plant height, but had 1.3-5.8 folds greater root dry weight, root length and root surface area, resulting in a significantly enhanced root: shoot dry mass ratio and root surface area: leaf area ratio. In addition, the introduction of Ri-genes conferred reduced stomatal pore aperture and increased stomatal density in the B3 line, and increased leaf thickness in A11 line, which could benefit plant drought resilience. Finally, the modulations in morphological traits as a consequence of transformation with Ri-genes are discussed concerning resilience in water-limited conditions. These findings reveal the potential of natural transformation with R. rhizogenes for drought-targeted breeding in crops.
Assuntos
Brassica napus , Raízes de Plantas , Brassica napus/genética , Brassica napus/microbiologia , Brassica napus/fisiologia , Brassica napus/anatomia & histologia , Raízes de Plantas/microbiologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia , Raízes de Plantas/genética , Agrobacterium/fisiologia , Agrobacterium/genética , Plantas Geneticamente Modificadas/genética , Secas , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Folhas de Planta/microbiologia , Folhas de Planta/genética , Transformação GenéticaRESUMO
For the Caatinga vegetation, it has not yet been definitively established which adaptive strategies best define the functional groups of woody plants and which syndromes emerge from the relationships between functional traits to achieve success in a semi-arid tropical region. To fill some of these gaps, we analyzed a specific set of characteristics that make up the LHS scheme of the plant ecological strategy (leaf-heigh-seed). The LHS scheme captures the functional niche of plants regarding the functional traits specific leaf area (SLA), plant height (HE), and seed mass (SM). We associate wood density (WD) to this scheme because this trait is a key feature for the identification of functional strategies in seasonally dry vegetation such as the Caatinga. We measured these characteristics in eight woody species and classified them according to their leaf phenology into deciduous and evergreen. The experiment was carried out between December 2017 and November 2018 in Caatinga areas located in the municipality of Barra de Santana, PB, a semiarid region of Brazil. Using cluster analysis, principal component analysis (PCA) and Pearson correlation analyses, we found significant relations between SLA and SM, and HE and WD. The SLA was the main predictor of plant strategy in the Caatinga. According to this characteristic, we identified two functional groups: species with a low SLA and species with a high SLA. We also recognized differences between deciduous and evergreen species based on the same trait. The traits measured, which represent the axes of the plant ecological strategy scheme LHS and wood density, are efficient in the discrimination of functional groups in the Brazilian semiarid. These groups relate to leaf phenology of woody species in this vegetation.
Assuntos
Madeira , Brasil , Madeira/classificação , Estações do Ano , Folhas de Planta/anatomia & histologia , Folhas de Planta/classificação , Folhas de Planta/fisiologia , Árvores/classificação , Sementes/classificação , Sementes/anatomia & histologia , Sementes/crescimento & desenvolvimento , Ecossistema , Clima TropicalRESUMO
Corn, as one of the three major grain crops in China, plays a crucial role in ensuring national food security through its yield and quality. With the advancement of agricultural intelligence, agricultural robot technology has gained significant attention. High-precision navigation is the basis for realizing various operations of agricultural robots in corn fields and is closely related to the quality of operations. Corn leaf and stalk recognition and ranging are the prerequisites for achieving high-precision navigation and have attracted much attention. This paper proposes a corn leaf and stalk recognition and ranging algorithm based on multi-sensor fusion. First, YOLOv8 is used to identify corn leaves and stalks. Considering the large differences in leaf morphology and the large changes in field illumination that lead to discontinuous identification, an equidistant expansion polygon algorithm is proposed to post-process the leaves, thereby increasing the average recognition completeness of the leaves to 86.4%. Secondly, after eliminating redundant point clouds, the IMU data are used to calculate the confidence of the LiDAR and depth camera ranging point clouds, and point cloud fusion is performed based on this to achieve high-precision ranging of corn leaves. The average ranging error is 2.9 cm, which is lower than the measurement error of a single sensor. Finally, the stalk point cloud is processed and clustered using the FILL-DBSCAN algorithm to identify and measure the distance of the same corn stalk. The algorithm combines recognition accuracy and ranging accuracy to meet the needs of robot navigation or phenotypic measurement in corn fields, ensuring the stable and efficient operation of the robot in the corn field.
Assuntos
Algoritmos , Folhas de Planta , Zea mays , Zea mays/anatomia & histologia , Folhas de Planta/anatomia & histologia , Robótica , Agricultura/métodos , Produtos Agrícolas , ChinaRESUMO
The highly invasive Impatiens glandulifera (Himalayan balsam) is one of the most prolific and widespread invasive plants in the British Isles. Introduced in the early nineteenth century, it has now been reported in almost every vice county across the UK and is a fierce competitor that has adverse effects on the local community structure. Despite the negative impacts that invaders like I. glandulifera have on local communities, there have been very few studies which address the morphological changes that invasive plant populations have undergone since their initial introduction. This is the first study of its kind to investigate the morphological changes that have occurred in I. glandulifera. 315 herbarium specimens dating from 1865 to 2017 were used to measure changes in morphological traits such as leaf size, flower length and stomatal characteristics. We found that since 1865, there has been a significant reduction in overall leaf size, a significant reduction in stomatal density and a significant increase in the overall flower length. These results highlight the importance of monitoring the evolutionary change in prolific alien species over the course of their invasion, providing useful insights into changes in competitive ability which may prove useful in managing dispersal and providing options for potential management.
Assuntos
Flores , Impatiens , Espécies Introduzidas , Folhas de Planta , Impatiens/anatomia & histologia , Reino Unido , Folhas de Planta/anatomia & histologia , Flores/anatomia & histologia , Estômatos de Plantas/anatomia & histologiaRESUMO
Various attributes are hypothesized to facilitate the dominance of an invasive species in non-native geographical and ecological regimes. To explore the characteristic invasive attributes of the family Asteraceae, a comparative study was conducted among nine species of this family, co-occurring in the western Himalayan region. Based on their nativity and invasion status, the species were categorized as "Invasive", "Naturalized", and "Native". Fifteen plant functional traits, strongly linked with invasion, were examined in the test species. The analyses revealed a strong dissimilarity between all the plant functional traits (except leaf carbon [Leaf C]) represented by "Invasive" and "Native" categories and most of the traits (except leaf area [LA], leaf nitrogen [Leaf N], Leaf C, and leaf carbon-nitrogen ratio [C: N]) represented by the "Naturalized" and "Native" categories. Similarly, "Invasive" and "Naturalized" categories also varied significantly for most of the traits (except Leaf N, Leaf C, capitula per m² population [Cm²], seeds per capitula [Scapitula], and seed mass). Invasive species are characterized by high LA, specific leaf area [SLA] and germination, and low C:N and leaf construction costs [LCC]. Most of the traits represented by native species justify their non-invasive behavior; whereas the naturalized species, despite having better size metrics (plant height), resource investment strategy (aboveground non-reproductive biomass [BNR], and aboveground reproductive biomass [BR]), and reproductive output (capitula per individual plant [Cplant], and seeds per individual plant [Splant]) failed to invade, which implies that the role of these functional aspects in imparting invasion potential to a species is not consistent in all the ecosystems and/or phylogenetic groups. Results of PCA revealed that trait divergence plays a more imperative role in invasion success than naturalization in the species of the family Asteraceae. The present study is intended to refine the pre-generalized invasion concepts associated with family Asteraceae to ensure more accurate identification of the potential invaders and better management of the existing ones.
Assuntos
Asteraceae , Espécies Introduzidas , Asteraceae/fisiologia , Asteraceae/genética , Folhas de Planta/fisiologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Carbono/metabolismo , Especificidade da EspécieRESUMO
MAIN CONCLUSION: Stomatal traits in rice genotypes affect water use efficiency. Low-frequency small-size stomata correlate with whole plant efficiency, while low-frequency large-size stomata show intrinsic efficiency and responsiveness to vapour pressure deficit. Leaf surface and the patterning of the epidermal layer play a vital role in determining plant growth. While the surface helps in determining radiation interception, epidermal pattern of stomatal factors strongly regulate gas exchange and water use efficiency (WUE). This study focuses on identifying distinct stomatal traits among rice genotypes to comprehend their influence on WUE. Stomatal frequency ranged from 353 to 687 per mm2 and the size varied between 128.31 and 339.01 µm2 among 150 rice germplasm with significant variability in abaxial and adaxial surfaces. The cumulative water transpired and WUE determined at the outdoor phenomics platform, over the entire crop growth period as well as during specific hours of a 24 h-day did not correlate with stomatal frequency nor size. However, genotypes with low-frequency and large-size stomata recorded higher intrinsic water use efficiency (67.04 µmol CO2 mol-1 H2O) and showed a quicker response to varying vapour pressure deficit that diurnally ranged between 0.03 and 2.17 kPa. The study demonstrated the role of stomatal factors in determining physiological subcomponents of WUE both at single leaf and whole plant levels. Differential expression patterns of stomatal regulatory genes among the contrasting groups explained variations in the epidermal patterning. Increased expression of ERECTA, TMM and YODA genes appear to contribute to decreased stomatal frequency in low stomatal frequency genotypes. These findings underscore the significance of stomatal traits in breeding programs and strongly support the importance of these genes that govern variability in stomatal architecture in future crop improvement programs.
Assuntos
Genótipo , Oryza , Folhas de Planta , Estômatos de Plantas , Transpiração Vegetal , Água , Oryza/genética , Oryza/fisiologia , Oryza/crescimento & desenvolvimento , Estômatos de Plantas/fisiologia , Estômatos de Plantas/genética , Água/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Transpiração Vegetal/fisiologia , Pressão de VaporRESUMO
PREMISE: Light is essential for plants, and local populations exhibit adaptive photosynthetic traits depending on their habitats. Although plastic responses in morphological and/or physiological characteristics to different light intensities are well known, adaptive divergence with genetic variation remains to be explored. This study focused on Saxifraga fortunei (Saxifragaceae) growing in sun-exposed and shaded habitats. METHODS: We measured the leaf anatomical structure and photosynthetic rate of plants grown in their natural habitats and in a common greenhouse (high- and low-intensity light experimental sites). To assess differences in ecophysiological tolerance to high-intensity light between the sun and shade types, we evaluated the level of photoinhibition of photosystem II and the leaf mortality rate under high-intensity light conditions. In addition, population genetic analysis was conducted to investigate phylogenetic origins. RESULTS: Clear phenotypic differences were found between the sun and shade types despite their recent phylogenetic origin. The leaf anatomical structure and photosynthetic rate showed plastic changes in response to growing conditions. Moreover, the sun type had a well-developed palisade parenchyma and a higher photosynthetic rate, which were genetically fixed, and a lower level of photoinhibition under high-intensity light. CONCLUSIONS: Our findings demonstrate that light intensity is a selective pressure that can rapidly promote phenotypic divergence between the sun and shade types. While phenotypic changes in multiple photosynthetic traits were plastic, genetic divergence in specific traits related to adaptation to high-intensity light would be fundamental for ecotypic divergence to different light regimes.
Assuntos
Adaptação Fisiológica , Fotossíntese , Saxifragaceae , Saxifragaceae/genética , Saxifragaceae/fisiologia , Sistema Solar , Ecossistema , Variação Genética , Microclima , Genética Populacional , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologiaRESUMO
Characterizing physiological and anatomical changes that underlie rapid evolution following climatic perturbation can broaden our understanding of how climate change is affecting biodiversity. It can also provide evidence of cryptic adaptation despite stasis at higher levels of biological organization. Here, we compared evolutionary changes in populations of Mimulus cardinalis from historically different climates in the north and south of the species' range following an exceptional drought. We grew seeds produced from predrought ancestral plants alongside peak-drought descendants in a common glasshouse and exposed them to wet and dry conditions. Before the drought, northern ancestral populations expressed traits contributing to drought escape, while southern ancestral populations expressed drought avoidance. Following the drought, both regions evolved to reduce water loss and maintain photosynthesis in dry treatments (drought avoidance), but via different anatomical alterations in stomata, trichomes, and palisade mesophyll. Additionally, southern populations lost the ability to take advantage of wet conditions. These results reveal rapid evolution towards drought avoidance at an anatomical level following an exceptional drought, but suggest that differences in the mechanisms between regions incur different trade-offs. This sheds light on the importance of characterizing underlying mechanisms for downstream life-history and macromorphological traits.
Assuntos
Evolução Biológica , Secas , Fotossíntese , Folhas de Planta , Folhas de Planta/fisiologia , Folhas de Planta/anatomia & histologia , Mimulus/fisiologia , Mimulus/genética , Mimulus/anatomia & histologia , Água/fisiologia , Estômatos de Plantas/fisiologia , Estômatos de Plantas/anatomia & histologiaRESUMO
A taxonomic revision of Rhizophora L. (Rhizophoraceae) in Thailand is presented. Two species, R. apiculata Blume and R. mucronata Poir., are enumerated with updated morphological descriptions, illustrations and a taxonomic identification key, together with notes on distributions, habitats and ecology, phenology, conservation assessments, etymology, vernacular names, uses, and specimens examined. Three names in Rhizophora, are lectotypified: R. apiculata and two associated synonyms of R. mucronata (i.e., R. latifolia Miq. and R. macrorrhiza Griff.). R. longissima Blanco, a synonym of R. mucronata, is neotypified. All two Rhizophora species have a conservation assessment of Least Concern (LC). Based on the morphological identification, these two species can be distinguished from one another by the shape and width of the leaf laminae and the length of a terminal stiff point of the leaf laminae; the type and position of the inflorescences and the number of flowers per inflorescence; the character and color of the bracteoles; the presence or absence of the flower pedicels; the shape of the mature flower buds; the shape, color, and texture of the sepals; the shape, character, and the presence or absence of hairs of the petals; the number of stamens per flower; the size of the fruits; the color and size of the hypocotyls; the color and diameter of the cotyledonous cylindrical tubes; and the color of the colleters and exudate. The thick cuticles, sunken stomata, large hypodermal cells, and cork warts are adaptive anatomical features of leaves in Rhizophora that live in the mangrove environments. The pollen grains of Thai Rhizophora species are tricolporate, prolate spheroidal or oblate spheroidal shapes, small-sized, and reticulate exine sculpturing.
Assuntos
Rhizophoraceae , Tailândia , Rhizophoraceae/anatomia & histologia , Ecossistema , Folhas de Planta/anatomia & histologiaRESUMO
Herbivory is a fundamental ecological force in the evolution of plant physiological, morphological, and chemical attributes. In this study, we explored how browsing pressure by local deer populations affected leaf form and function in two California native tree species, Quercus agrifolia (coast live oak) and Umbellularia californica (California bay laurel). Specifically, we investigated how leaf and stem vascular attributes differed between browsed and non-browsed zones of each species. Browsing significantly altered traits such as leaf to phloem ratios and leaf area, but we observed few meaningful differences in leaf and stem anatomy between browsed and non-browsed material. We discuss these results in the context of leaf and stem adaptations to herbivory and water use efficiency and explore future research considerations for investigating leaf and stem vascular trait development with herbivore presence.
Assuntos
Herbivoria , Folhas de Planta , Quercus , Quercus/fisiologia , Herbivoria/fisiologia , Animais , Folhas de Planta/fisiologia , Folhas de Planta/anatomia & histologia , Especificidade da Espécie , Caules de Planta/fisiologia , Caules de Planta/anatomia & histologia , Cervos/fisiologia , CaliforniaRESUMO
BACKGROUND: In plants, the leaf functions as a solar panel, where photosynthesis converts carbon dioxide and water into carbohydrates and oxygen. In soybean, leaf type traits, including leaf shape, leaf area, leaf width, and leaf width so on, are considered to be associated with yield. In this study, we performed morphological characterization, transcriptome analysis, and endogenous hormone analysis of a rolled and narrow leaf mutant line (rl) in soybean. RESULTS: Compared with wild type HX3, mutant line rl showed rolled and narrower leaflet, and smaller leaf, meanwhile rl also performed narrower pod and narrower seed. Anatomical analysis of leaflet demonstrated that cell area of upper epidermis was bigger than the cell area of lower epidermis in rl, which may lead rolled and narrow leaf. Transcriptome analysis revealed that several cytokinin oxidase/dehydrogenase (CKX) genes (Glyma.06G028900, Glyma.09G225400, Glyma.13G104700, Glyma.14G099000, and Glyma.17G054500) were up-regulation dramatically, which may cause lower cytokinin level in rl. Endogenous hormone analysis verified that cytokinin content of rl was lower. Hormone treatment results indicated that 6-BA rescued rolled leaf enough, rescued partly narrow leaf. And after 6-BA treatment, the cell area was similar between upper epidermis and lower epidermis in rl. Although IAA content and ABA content were reduced in rl, but exogenous IAA and ABA didn't affect leaf type of HX3 and rl. CONCLUSIONS: Our results suggest abnormal cytokinin metabolism caused rolled and narrow leaf in rl, and provide valuable clues for further understanding the mechanisms underlying leaf development in soybean.
Assuntos
Perfilação da Expressão Gênica , Glycine max , Folhas de Planta , Glycine max/genética , Glycine max/crescimento & desenvolvimento , Glycine max/anatomia & histologia , Glycine max/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Transcriptoma , Mutação , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Citocininas/metabolismo , FenótipoRESUMO
Leaf Area Index (LAI) is the ratio of ground surface area covered by leaves. LAI plays a significant role in the structural characteristics of forest ecosystems. Therefore, an accurate estimation process is needed. One method for estimating LAI is using Digital Cover Photography. However, most applications for processing LAI using digital photos do not consider the brown color of plant parts. Previous research, which includes brown color as part of the calculation, potentially produced biased results by the increased pixel count from the original photo. This study aims to enhance the accuracy of LAI estimation. The proposed methods consider the brown color while minimizing errors. Image processing is carried out in two stages to separate leaves and non-leaf pixels by using the RGB color model for the first stage and applying the CIELAB color model in the second stage. Proposed methods and existing applications are evaluated against the actual LAI value obtained using Terrestrial Laser Scanning (TLS) as the ground truth. The results demonstrate that the proposed methods effectively identify non-leaf parts and exhibit the lowest error rates compared to other methods. In conclusion, this study provides alternative techniques to enhance the accuracy of LAI estimation in forest ecosystems.