Leaf Anatomical Characteristics Research Articles

Comprehensive evaluation of 17 tea germplasm resources in Jiangxi based on leaf anatomical structure characteristics

Comprehensive evaluation of 17 tea germplasm resources in Jiangxi based on leaf anatomical structure characteristics

Niche and phenotypic differentiation in fern hybrid speciation, a case study of Pteris fauriei (Pteridaceae).

Niche differentiation is a critical issue in speciation. Although it has a well-known role in adaptive processes of hybrid angiosperms, it is less understood in hybrid ferns. Here we investigate whether an intermediate ecological niche of a fern hybrid is a novel adaptation that provides insights into fern hybrid speciation. Pteris fauriei (Pteridaceae) is a natural hybrid fern, occurring environments between its parent species. The maternal P. minor is found in sunny areas, but the habitat of the paternal P. latipinna is shady. We combined data from morphology, leaf anatomy, and photosynthetic traits to explore adaptation and differentiation, along with measuring the environmental features of their niches. We also performed experiments in a common garden to understand ecological plasticity. The hybrid P. fauriei is intermediate between the parent species in stomatal density, leaf anatomical features, and photosynthetic characteristics in both natural habitats and a common garden. Interestingly, the maternal P. minor showed significant environmental plasticity and was more similar to the hybrid P. fauriei in the common garden, suggesting that the maternal species experiences stress in its natural habitats but thrives in the environments similar to the hybrid's. Based on the similar niche preferences of the hybrid and parents, we propose hybrid superiority. Our results indicate that the hybrid P. fauriei exhibits greater fitness and can compete with and occupy the initial niches of the maternal P. minor. Consequently, we suggest that the maternal P. minor has experienced a niche shift, elucidating the pattern of niche differentiation in this hybrid group. These findings offer a potential explanation for the frequent occurrence of hybridization in ferns and provide novel insights into fern hybrid speciation, enhancing our understanding of fern diversity.

Determining Formaldehyde Phytoremediation Efficacy of Selected Ornamental Plants

In the recent past, deterioration of indoor air quality has become a serious concern due to the increased energy efficiency and reduced air exchange rate inside urban buildings. Volatile organic compounds (VOCs) are a major category of indoor air pollutants that can lead to adverse health outcomes such as headaches, allergies and asthma in those exposed for prolonged periods. Formaldehyde, the VOC used in the present study is a common contaminant of indoor air which originates from particle board, plywood, paper products, certain adhesives, tobacco smoke and other sources. The use of plants for the mitigation of indoor air pollution is viewed as a cost effective and eco-friendly method with untapped potential. The main objective of the present study was to determine the formaldehyde removal efficacy of selected plant species while investigating the mechanisms used by these plants in the removal process. The selected plant species were Zamioculcas zamiifolia, Hedera helix, Dracaena sanderiana and Ficus sp. Plants of the same age were used with three replicates from each species. Phytoremediation potential was assessed by exposing the plants for 24 hours to gaseous formaldehyde (2.0 μL L-1) in air tight chambers made of Plexiglass (an inert material for VOCs) with dimensions of 0.9 m height×0.58 m length×0.55 m width. Formaldehyde removal was measured using GC-MS and the result was expressed as removal percentages. Several leaf anatomical characters (cuticle thickness, epidermal thickness and mesophyll layer thickness), stomatal characters (stomatal density, stomatal index, guard cell length and potential conductance index) and physiological characters (stomatal conductance and photosynthetic rate) were measured to study the possible mechanisms involved in the formaldehyde removal process. The data were subjected to ANOVA and Pearson correlation test. According to the results obtained, Ficus sp. had the highest formaldehyde removal percentage (92.80%) while Hedera helix had the lowest (56.86%). The study further showed that stomatal density and stomatal conductance play a major role in formaldehyde removal by these plants while cuticle and epidermal thickness act as hindrances to this process. This conclusion was further confirmed by Pearson‘s correlation values in correlation analysis. The current study was carried out for 24 hours of exposure and it would be of interest to explore, the long term behavior of the plants through further studies. Overall, the results justify future studies on a cross-section of diverse plant species for formaldehyde removal efficiency to determine species with superior removal efficiencies for a better phytoremediation process. 
 Keywords: Phytoremediation, VOCs, Formaldehyde, GC-MS technology

Characterization of anatomical characters of Peperomia (Piperaceae) from Asia for taxonomy

Abstract The flowers of Peperomia (Piperaceae) are simple, minute, and unique structures within the angiosperms consisting of a rounded bract, two stamens and an ovary, but generally lack taxonomic value at species level. Because of this, morphological characters of vegetative parts have been mainly used for species level taxonomy. There is a need to supplement these vegetative characters with anatomical characters. We selected 17 native Thai species representatives of South East Asian Peperomia to investigate the utility of vegetative anatomical characters for species delimitation, taxon identification, and classification. Stem, petiole, and leaf anatomical characters were studied using standard microscopic techniques. The anatomical characters demonstrated high diversity and supported species identification. Unweighted Pair Group Method with Arithmetic Mean (UPGMA) culstering, Principal Coordinates analysis (PCoA), and Principal Component Anaysis (PCA) were used to investigate patterns in the multivariate anatomical data and identify groupings of value to species classification. Four broad groupings were retrieved and some subgroupings identified. The most important characters that differentiated the species in the multivariate analysis included stem shape (roundness and ridges), petiole indumentum and trichome type, vascular bundle pattern and number, stem pith cavity, mucilage canals, and stem cortex sclerenchyma. These data were further used to prepare anatomical descriptions at generic and species levels and to provide a key to species.

Leaf anatomy of seven endemic species of Glicophyllum (Malpighiaceae) in Brazil.

Glicophyllum is well supported, presenting four homoplasies, easily differentiated from the other genera of the clade due to characteristics related to the reproductive organs, which can make the identification of their species difficult when they are not in the reproductive phase. Therefore, there are provided the leaf anatomical and morphological description of the leaf glands of seven species of Glicophyllum to assist in the identification of their species. The samples for the study were obtained from several national and international herbaria, sectioned freehand, stained with basic fuchsin - astra blue and compared through a binary matrix using the Sorensen's coefficient in the MVSP software. Among the leaf anatomical characters found, the following stand out: presence/absence of trichomes; petiole contour; contour of the main vein; organization of the mesophyll, presence/absence of bundle sheath extension and the surface of the glands. In this study, an identification key with leaf anatomical data is presented for the first time, demonstrating the applicability of leaf anatomy for the taxonomy of Glicophyllum. In the multivariate analysis, it is observed that the characteristics of leaf venation and topology of the glands are more representative to differentiate the taxa. Therefore, the data obtained can support future taxonomic and phylogenetic studies of the genus.

COMPARATIVE LEAF ANATOMY AND MICROMORPHOLOGY OF ASYSTASIA GANGETICA T.ANDERSON SUBSP. MICRANTHA (NEES) ENSERMU AND RHINACANTHUS NASUTUS (L.) KURZ (JUSTICIINAE, ACANTHACEAE) FROM PENINSULAR MALAYSIA

Acanthaceae family has been used traditionally for medicinal purposes, especially amongst the native communities in Peninsular Malaysia. Nowadays, many taxonomists have difficulties in the identification of the Acanthaceae species due to its morphological similarities and when there is an incomplete part of plants obtained from the field sampling. But until now, there is no comprehensive study that has been documented especially on the Acanthaceae family, specifically for A. gangetica subsp. micrantha and R. nasutus. To avoid incorrect species identification, a systematic study that involved the leaf anatomy and micromorphology parts is being used for the identification and classification of plants in the Acanthaceae. Therefore, the main objective of this present study is to identify the leaf anatomical and micromorphological characteristics that can be used in plant identification and for supportive data in plant classification. The leaf anatomical and micromorphological studies that are conducted on species studied involve several procedures such as cross-section using a sliding microtome, and observation under a light microscope and scanning electron microscope. The anatomical and micromorphological characteristics observed that have been used to identify each species studied include patterns of petiole and midrib vascular bundles, leaf margin, leaf lamina, presence of cuticular striae, and the presence of trichomes. The results of this study showed that the cystolith cells can be found only in midrib of A. gangetica subsp. micrantha while it also recorded in petiole, midrib, and the leaf lamina of R. nasutus. Observation under the light microscope revealed nine types of trichomes in R. nasutus meanwhile seven trichomes were recorded in A. gangetica subsp. micrantha. Other than that, the present of cuticular striae only recorded at the abaxial epidermis of A. gangetica subsp. micrantha. In conclusion, results showed that anatomical and micromorphological characteristics have taxonomic significance that can be used in the identification and classification, especially at the species level

TAXONOMIC STUDY OF SOME EUPHORBIA L. SPECIES BY LEAF ANATOMICAL AND MOLECULAR CHARACTERISTICS USING RBCL AND MATK GENES

A current study assessed the leaf anatomical and molecular characteristics of eight species of the genus Euphorbia (Euphorbiaceae), i.e., E. craspedia Boiss, E. denticulate Lam., E. falcate L., E. hirta L., E. helioscopia L., E. peplus L., E. kansuensis L., and E. macroclada Boiss ,collected from several districts of the Middle and Northern Iraq. The anatomical result refers to a uniseriate epidermis (single layer), except for the species E. kansuensis and E. peplus, wherein the upper epidermis recorded a variable thickness among the species. The highest epidermis thickness (28 μm) was visible in the species E. falcata, while the mean decreased to 17 μm in the species E. helioscopia. Based on the anatomical attributes, further species groupings resulted in two. In the first group, the leaf’s crosssection was unifacial, with the palisade tissues on both sides of the blade. This group included E. hirta, E. peplus, E. macroclada?, and E. denticulata. Contrastingly, the second group has a bifacial leaf, with the mesophyll distinguished as palisade and spongy. The said group comprised the E. craspedia and E. helioscopia species. In the genus Euphorbia species, the study of the genetic relationship continued according to the sequencing method of rbcl and matk genes. The results revealed that most species samples showed light bands, characterized by their intensity ranging from 800 to 1000 bp. The highest recorded genetic affinity through the rbcl gene emerged in E. denticulata and E. kansuensis, whereas the lowest was in E. macroclada and E. hirta. Based on matk gene results, the highest genetic affinity observed resulted in the species E. kansuensis and E. denticulata with an average value of 0.0160, with the lowest recorded in the species E. helioscopia and E. peplus with a value of 0.1307.

COMPARISONS OF ANATOMICAL TRAITS IN DIFFERENT LEAF POSITIONS OF DIVERSE SETS OF SUGARCANE GENOTYPES

Research on appropriate leaf positions in diverse sugarcane genotypes is crucial due to the significance of leaf anatomical characteristics in determining plant adaptability. This study aimed to compare the anatomical traits among the varied leaf positions within a tiller and tillers under normal conditions. A randomized complete block design (RCBD) setup used four replications. Four commercial canes, two wild types, and three F1 interspecific hybrids underwent examination on leaf thickness (LT), cuticle thickness percentage (CT%), vertical length bulliform cell percentage (VBC%), and stomatal crypt depth percentage (SCD%) across 1st to 5th leaf positions on main, first, and second tillers. The 1st to 5th leaf positions had no differences when compared within the tiller in commercial and wild cultivars for LT, CT%, VBC%, and SCD% traits, and F1 hybrids demonstrated no variation in CT% and VBC% traits. The LT, SCD, and CT of commercial canes had a high proportion, and VBC had a slender shape and a large size. Inversely, the wild type had a low LT but high SCD and CT and a circular shape with a small size VBC. Leaf anatomy in the F1 hybrid resembled the wild type, and leaf positions 1st to 3rd were not different among tillers, but the 4th and 5th leaf positions differed. Therefore, anatomical trait collection should continue among 1st to 3rd leaf positions for all sugarcane types. Moreover, the 1st to 3rd leaf positions within the 1st and 2nd tillers can represent the anatomical performance of the main tiller in commercial cane cultivars

Comparative anatomical and morphological studies on leaves of some Citrus species and their systematic implications

In this study, leaf micromorphological features of 42 accessions of 12 species of the genus Citrus were assessed through light microscopy and scanning electron microscopy, to evaluate phylogenetically significant characters that delineate species. Morphometrical analyses were carried out using the leaf anatomical and micromorphological characters of at least five samples collected from different localities. Some leaflet anatomical traits (cuticle ornamentation, cyclocytic and tetracytic stomata, isobilateral mesophyll arrangement, number of palisade layers, shape of the midrib, sheath around vascular tissue) clearly support various clades defined by previous DNA-based phylogenetic work. Anatomical features of C. limetta and C. aurantifolia were identical, thus supporting the synonimisation of these two species. Leaf anatomy and morphology in the studied taxa reveal many characters high value for infrageneric classification of Citrus. This work provides useful background for further molecular and anatomical studies of Citrus.

Anatomical and micromorphological characteristics of Pogostemon heyneanus Benth. (Lamiaceae)

Foliar micromorphological and anatomical characteristics of Pogostemon heyneanus Benth. (Lamiaceae) was investigated in order to describe its comprehensive characterization and its association with the presence of essential oils. The methods used in this study involved several methods such as cross-section using a sliding microtome and epidermal peeling that were observed under light microscope, and foliar micromorphological characteristics that were observed under scanning electron microscope (SEM). Results showed leaf anatomical and micromorphological characteristics that could be useful in species identification and the localization of chemical properties. The leaf epidermal surfaces were characterized by curved to sinuous anticlinal walls (adaxial side) and sinuous anticlinal walls (abaxial side). The diacytic and anisocytic types of stomata were present only on the abaxial surface. The features of the stem is quadrangular and the well-developed collenchyma function. The sclerenchyma cells are present as clusters at the outer layer of vascular bundles and continuously surround the vascular tissue. Then, there were three forms of crystals found, namely star shaped crystals, prismatic crystals and raphides in the pith area. Eight types of trichomes were observed: simple unicellular, simple multicellular, peltate, short-stalked capitate (unicellular head), short-stalked capitate (bicellular head), short-swollen multistalked (unicellular acute head), long-stalked capitate, and long-swollen stalked capitate (disk head) trichomes. The presence of various glandular trichomes on the leaf surfaces may serve as secretory sites where secondary metabolites or essential oils are produced. The findings on the foliar and stem anatomical and micromorphological characteristics are very useful for the medicinal herbs industry as well as being of taxonomic value.

Türkiye'de Yetişen Beş Artemisia L. Türünün Gövde Ve Yaprak Anatomisinin İncelenmesia

In this study, it is aimed to make anatomical analysis of five different Artemisia L. species (A. absinthium L., A. annua L., A. abrotanum L., A. incana (L.) Druce, A. tournefortiana Rchb.) grown in Turkey and contribute to the definition of this genus, which has some taxonomic problems. The materials for anatomical study were preserved in 70% alcohol. Free hand cross sections were taken using sharp razor blades, stained and mounted in Sartur Reagent and Chloralhydrate (50%) solution. Anatomical structures of the stem and leaf of selected species were examined under the light microscope. Their detailed structures were illustrated with photographs. Results have shown that stem and leaf anatomical features of the Asteraceae family are mostly shared by all species. However, some characters could be considered species-specific. In cross- sections, the stems of all studied species have more or less irregular rounded shapes, but prominent ribs containing collenchyma tissue could be noticed only in A. annua stem. The leaves of A. absinthium and A. incana were covered by glandular and densely T-shaped non--glandular trichomes on both sides however, A. tournefortiana had no hair at all. There were highly apparent secretory canals located in both the stem (next to the endodermal cells) and the leaf (near to xylem) of A. tournefortiana. The anatomical structure of leaves and stems of A. tournefortiana and A. incana growing in Turkey was demonstrated for the first time. Our results revealed that the studied species are anatomically distinguishable from each other and also provided valuable features for better species identification and contribute to the anatomy of the genus Artemisia.

MICROMORPHOLOGICAL AND ANATOMICAL RESPONSES OF NATIVE DICOTS TO INDUSTRIAL EFFLUENTS RELEASED FROM CONTAMINATED REGION OF THE CHENAB RIVER IN PAKISTAN

Faisalabad industrial units discharge effluents and associated toxic chemicals into the environment, deteriorating ecological conditions and ecosystem health. Morphoanatomical changes in some medicinally important native species (Calotropis procera, Eclipta alba, Phyla nodiflora, and Ranunculus sceleratus) exposed to heavy industrial pollution gained evaluation. These species of choice were due to their widespread distribution in the area. Ten sites selected in the River Chenab, Chiniot, had three near point source pollution of Faisalabad industries within the 500-m radius (polluted) at three drains and two sites inside the river after each drain point source with the control site at 14 km after from the first industrial drain point source. The general response of all plants to effluents was growth retardation. Plant height increased significantly in all species from river sites. An increase in tallness was more prominent in species like C. procera and P. nodiflora. An increase in stem sclerification in C. procera and E. alba from polluted sites occurred, which indicated a better ability to tolerate industrial pollution. Remarkable increases in stem and leaf epidermis, intensive stem sclerenchyma, and closely packed stem vascular bundles in C. procera appeared, which could increase resistance to industrial pollution. Most of the morphoanatomical parameters notably attained a decrease in E. alba, the most vulnerable species. Plant survival depends on particular structural changes in dermal, mechanical, parenchymatous, and vascular tissues. Overall, industrial pollution adversely impacts plant morphological and micromorphological features, although the reaction of specific species to industrial contamination varies. The study determined that stem and leaf anatomical features, such as, epidermis size and storage tissue thickness, are suitable morphoanatomical markers for industrial pollution biomonitoring. Internal modifications of plants vegetating different industrial contaminated sites played a significant role in high tolerance levels.

Features of the anatomical structure of leaves depending on the high-altitude growth of apricot in Dagestan

Background. The adaptive changes during the distribution of Prunus armeniaca L. in Dagestan are important for understanding microevolution, structural and functional differentiation processes of populations along environmental gradients based on the organism’s reaction norm. They can be examined by studying leaf anatomical features, having ecologically differentiating significance in natural populations with contrasting growth conditions. Materials and methods. The material for the study of leaf anatomical features was taken from 7 apricot trees in 3 growing areas of Mountainous Dagestan. Comparative analysis was carried out for 42 morphological, anatomical and index parameters of the lamina and petiole. Results. The anocytic structure type of the stomatal apparatus was found in all apricot samples. The differences were determined by the degree of stomata submergence depending on the cuticle’s development. Trees from greater heights had more trichomes on the leaf’s upper side than on its underside. Significant differences between the extreme height reference points were recorded for the number of stomata, cells of the lower epidermis, layers of the sclerenchyma, and xylem thickness. Most of the traits of the lamina decreased, and those of the petiole increased with the altitude. Conclusion. The traits corresponding to the lower and upper altitude limits of P. armeniaca were identified on the basis of the lamina and petiole anatomical features. More xerophytic leaf traits were recorded for the altitudes of 550 m and 1900 m, and mesophytic ones for 1700 m and 1800 m. Endoderm thickness, number of endosperm layers, petiole index, and stomatal index were identified as stable indicators according to the reaction norm within the scope of altitudes: The differences were proved for more plastic traits (number of cells of the upper and lower epidermis, number of stomata, thickness of the lamina and cuticle, and the petiole’s long axis diameter).

Response of Carex breviculmis to phosphorus deficiency and drought stress.

The drought and phosphorus deficiency have inevitably become environmental issues globally in the future. The analysis of plants functional trait variation and response strategies under the stress of phosphorus deficiency and drought is important to explore their ability to respond to potential ecological stress. In this study, Carex breviculmis was selected as the research object, and a 14-week pot experiment was conducted in a greenhouse, with two phosphorus treatment (add 0.5mmol/L or 0.05μmol/L phosphorus) and four drought treatment (add 0-5%PEG6000), totaling eight treatments. Biomass allocation characteristics, leaf anatomical characteristics, biochemical parameters, root morphology, chemical element content, and photosynthetic parameters were measured. The results showed that the anatomical characteristics, chemical elements, and photosynthetic parameters of Carex breviculmis responded more significantly to main effect of phosphorus deficiency. Stomatal width, leaf phosphorus content and maximum net photosynthetic rate decreased by 11.38%, 59.39%, 38.18% significantly (p<0.05), while the change in biomass was not significant (p>0.05). Biomass allocation characteristics and root morphology responded more significantly to main effect of drought. Severe drought significantly decreased leaf fresh weight by 61% and increased root shoot ratio by 223.3% compared to the control group (p<0.05). The combined effect of severe drought and phosphorus deficiency produced the highest leaf N/P ratio (291.1% of the control) and MDA concentration (243.6% of the control). Correlation analysis and redundancy analysis showed that the contributions of phosphorus and drought to functional trait variation were similar. Lower epidermal cell thickness was positively correlated with maximum net photosynthetic rate, leaf phosphorus, chlorophyll ab, and leaf fresh weight (p<0.05). In terms of response strategy, Carex breviculmis was affected at the microscopic level under phosphorus deficiency stress, but could maintain the aboveground and underground biomass well through a series of mechanisms. When affected by drought, it adopted the strategy of reducing leaf yield and improving root efficiency to maintain life activities. Carex breviculmis could maintain its traits well under low phosphorus and moderate drought, or better conditions. So it may have good ecological service potential in corresponding areas if promoted. This study also provided a reference for plant response to combined drought and phosphorus deficiency stresses.

Young stem and leaf anatomy of 15 Malagasy-endemic Diospyros species (Ebenaceae): taxonomic implications

Abstract Eighty-eight of the 255 Diospyros species from Madagascar are potential sources of ebony wood. Unfortunately, several species are currently threatened with extinction due in part to illegal and unsustainable logging. Reliable identification of living Diospyros species is necessary prior to any sustainable exploitation, so as not to compromise those species threatened with extinction. This study aims to identify features that might contribute to supporting taxonomic studies and to provide a complementary tool for the identification of standing trees. Fifteen species of Diospyros endemic to Madagascar were studied using standard anatomical methods. Each species showed a different shape of the leaf midrib and some have distinctive leaf anatomical characteristics, such as the presence of extrafloral nectaries in the distal part of the petiole in Diospyros baronii and filiform sclerenchyma in the mesophyll in Diospyros lewisiae. Statistical analysis showed that petiole and midrib vascular patterns, spongy parenchyma structure, the presence of papillae, thickness of epidermis, presence of extrafloral nectaries, stratification of epidermis, and presence of a cuticle are useful to distinguish species groups and even some species. The anatomy of young stems and leaves of Diospyros species from Madagascar is examined for the first time; the study will be extended to other potentially exploitable species.

Diurnal Variations of Photosynthesis and Leaf Anatomical Characteristics of Cornus Walteri Wanger Seedlings Under Different Light Regimes

Diurnal variations of photosynthesis and leaf anatomical structure characteristics of Cornus walteri seedlings under three light conditions, including L0 (under full light radiation), L1 (under natural tree shade), L2 (under one layer of shading) were studied. Results showed that, Pn under different light regimes showed asymmetric convex linear changes. The variation of Pn under L0 was the strongest; the maximum of Pn appeared at 12:00 AM, that of Gs was so. Photosynthetic Active Radiation (PAR) under L2 was insufficient, so Pn decreased significantly, and the peak was at 10:00 AM. Pn and Gs under L1 changed gently.The daily average sequence of Pn was L0＞L2＞L1 and Ci showed the reverse sequence. Shading had a significant effect on photosynthetic response parameters of Cornus walteri seedlings, which caused a significant decrease of LCP, LSP, and decline of Pnmax，AQY and Rd was so. Under shading, leaves of Cornus walteri seedlings became thinner, thickness of epidermal cells (EP) decreased significantly, thickness of both PT and ST reduced. Cornus walteri was intolerant tree species, which has certain physiological regulation ability to weak light, but severe shading will hinder seedling growing. So it was suggested to raise seedlings under full light, and create a favorable condition for seedlings growing. Bangladesh J. Bot. 52(2): 395-402, 2023 (June)

Morpho-anatomical determinants of yield potential in Olea europaea L. cultivars belonging to diversified origin grown in semi-arid environments.

Plant performance is mainly estimated based on plant architecture, leaf features and internal microstructural changes. Olive (Olea europaea L.) is a drought tolerant, oil yielding, and medium sized woody tree that shows specific structural and functional modifications under changing environment. This study was aimed to know the microstructural alteration involving in growth and yield responses of different Olive cultivars. Eleven cultivars were collected all over the world and were planted at Olive germplasm unit, Barani Agricultural Research Institute, Chakwal (Punjab) Pakistan, during September to November 2017. Plant material was collected to correlate morpho-anatomical traits with yield contributing characteristics. Overall, the studied morphological characters, yield and yield parameters, and root, stem and leaf anatomical features varied highly significantly in all olive cultivars. The most promising cultivar regarding yield was Erlik, in which plant height seed weight and root anatomical characteristics, i.e., epidermal thickness and phloem thickness, stem features like collenchymatous thickness, phloem thickness and metaxylem vessel diameter, and leaf traits like midrib thickness, palisade cell thickness a phloem thickness were the maximum. The second best Hamdi showed the maximum plant height, fruit length, weight and diameter and seed length and weight. It also showed maximum stem phloem thickness, midrib and lamina thicknesses, palisade cell thickness. Fruit yield in the studied olive cultivars can be more closely linked to high proportion of storage parenchyma, broader xylem vessels and phloem proportion, dermal tissue, and high proportion of collenchyma.

Responses of two strawberry cultivars to NaCl-induced salt stress under the influence of ZnO nanoparticles

Salinity stress is one of the most serious impacts of climate changes on agriculture production, especially in salt sensitive crop plants, like strawberry. Currently, the utilization of nanomolecules in agriculture is thought to be a useful strategy to compact abiotic and biotic stresses. This study aimed to investigate the effect of zinc oxide nanoparticles (ZnO-NPs) on the in vitro growth, ions uptake, biochemical and anatomical responses of two strawberry cvs (Camarosa and Sweet Charlie) under NaCl-induced salt stress. A 2x3x3 factorial experiment was conducted, with three levels of ZnO-NPs (0, 15 and 30 mg 1-l) and three levels of NaCl-induced salt stress (0, 35 and 70 mM). The results showed that increased levels of NaCl in the medium had led to decrease in shoot fresh weight and proliferative potential. The cv Camarosa was found to be relatively more tolerant to salt stress. Additionally, salt stress leads to an accumulation of toxic ions (Na + and Cl-), as well as a decrease in K + uptake. However, application of ZnO-NPs at a concentration of 15 mg 1-l was found to alleviate these effects by increasing or stabilizing growth traits, decreasing the accumulation of toxic ions and the Na+/K + ratio, and increasing K + uptake. Additionally, this treatment led to elevated levels of catalase (CAT), peroxidase (POD) and proline content. The positive impacts of ZnO-NPs application were reflected on the leaf anatomical features, being better adapted to salt stress. The study highlighted the efficiency of utilizing tissue culture technique in screening of strawberry cultivars for salinity tolerance under the influence of NPs.

Variations in leaf anatomical characteristics drive the decrease of mesophyll conductance in poplar under elevated ozone.

Decline in mesophyll conductance (gm ) plays a key role in limiting photosynthesis in plants exposed to elevated ozone (O3 ). Leaf anatomical traits are known to influence gm , but the potential effects of O3 -induced changes in leaf anatomy on gm have not yet been clarified. Here, two poplar clones were exposed to elevated O3 . The effects of O3 on the photosynthetic capacity and anatomical characteristics were assessed to investigate the leaf anatomical properties that potentially affect gm . We also conducted global meta-analysis to explore the general response patterns of gm and leaf anatomy to O3 exposure. We found that the O3 -induced reduction in gm was critical in limiting leaf photosynthesis. Changes in liquid-phase conductance rather than gas-phase conductance drive the decline in gm under elevated O3, and this effect was associated with thicker cell walls and smaller chloroplast sizes. The effects of O3 on palisade and spongy mesophyll cell traits and their contributions to gm were highly genotype-dependent. Our results suggest that, while anatomical adjustments under elevated O3 may contribute to defense against O3 stress, they also cause declines in gm and photosynthesis. These results provide the first evidence of anatomical constraints on gm under elevated O3 .

Foliar micromorphology with emphasis on the trichomes diversity and its taxonomic relevance in selected tribes of Asteraceae from Hainan Island

The Asteraceae is one of the most taxonomically complex, medicinally and economically important family among the angiosperms. Therefore, this study aims to evaluate the leaf anatomical features to correctly identify the Asteraceae species of Hainan Island. Scanning electron microscopy was used to investigate various micro epidermal traits. Leaf micromorphology of all the species was characterized, visualized and compared using UPGMA Cluster analysis (CA), chord diagram and ridgeline plot. Generally, the trichomes were divided into two main categories, glandular trichomes (GTs) and non-glandular trichomes (NGTs). The GTs was further classified into capitate, subsessile and sessile capitate. The NGTs were classified into long falcate, short conical, lipidote and filiform. The stomata were mostly anomocytic and anisocytic sometimes mixed with tetracytic type. However, there are varied assortments of trichomes and stomata with transitions among them especially in their type, frequency and number of cells. The trichomes and stomata can be successfully used for the delimitation of the genera within the family. The statistical analysis can help in better understanding of the results that characterized, visualized and compared the leaf anatomical traits of the Asteraceae taxa. Overall, these traits collectively have a significant taxonomic potential to identify and define species boundaries at the tribe and generic levels and can be used as an additional tool for regrouping taxa within Asteraceae.