Leaf Lamina Research Articles

Non-invasive laser bio-speckle technique for the study of optical irradiation on plant leaf lamina: Application to monitor salicylic acid modulated response in Zamioculcas zamiifolia

The intensity of light is one of the major factors influencing the rate of plant physiological activity. For optimization of the agricultural lighting necessary for plant growth, it is vital to understand the plant behavioral response under different light intensities. In the present study, the dynamic activity due to the physiological phenomena in the leaf of a plant when exposed to optical radiation from artificial LED sources is quantified non-destructively. The laser bio-speckle algorithm of obtaining Inertia Moment (IM) values from the Time History of Speckle Patterns (THSP) is utilized as a quantitative measure of the plant leaf dynamic activity. The plant leaf laminas were probed using the laser and the IM values were generated. The dynamic activity variations with the increase in optical intensity were studied on the leaves of Philodendron erubescens, Syngonium podophyllum, Piper nigrum, Plectranthus amboinicus and Epipremnum aureum. The obtained results reveal a unique pattern for each plant leaf and displayed consistent repeatability under fixed experimental conditions. The method was extended to monitor dynamic activity variation with optical irradiation intensity in Zamioculas zamiifolia leaves before and after treatment with salicylic acid, a measure to induce hormonal cross-talks. The obtained results were validated using biochemical estimation techniques and can be useful insights for the development of a non-invasive sensor for analyzing the plant's physiological activity under various light intensity conditions. The present study is the first of its kind to elucidate the viability of conducting a non-invasive analysis of abiotic stress effects on a sample and control plant using laser speckle technique.

Xylem and Phloem in Petioles Are Coordinated With Leaf Gas Exchange in Oaks With Contrasting Anatomical Strategies Depending on Leaf Habit.

As the single link between leaves and the rest of the plant, petioles must develop conductive tissues according to the water influx and sugar outflow of the leaf lamina. A scaling relationship between leaf area and anatomical traits of xylem and phloem is expected to improve the efficiency of these tissues. However, the different constraints compromising the functionality of both tissues (e.g., risk of cavitation) must not be disregarded. Additionally, deciduous and evergreen plants may have different strategies to produce and package their petiole conduits to cope with environmental restrictions. We explored in 33 oak species the relationships between petiole anatomical traits, leaf area, stomatal conductance, and photosynthesis rate. Results showed allometric scaling between anatomical structure of xylem and phloem with leaf area. We also found correlations between photosynthesis rate, stomatal conductance, and anatomical traits in the petiole. The main novelty is how oaks present a different strategy depending on the leaf habit. Deciduous species tend to increase their diameters to achieve greater leaf-specific conductivity. By contrast, evergreen oaks develop larger xylem conductive areas for a given leaf area than deciduous ones. This trade-off between safety-efficiency in petioles has never been attributed to the leaf habit of the species.

Deciphering Regulatory Role of Melatonin in Foliar Nastic Movements of Portulaca oleracea: Visual Insights from Histology and Anatomy

AbstractPlant nastic movements exhibit unique behavioural patterns that synchronize with external cues. Given that the foliar nastic motions of Portulaca species are solely circadian, it is intriguing to investigate whether and how melatonin governs these movements. Analysis of histological traits concurrent with anatomical traits such as stomatal behaviour provides visual data on the plant species' gnosophysiology, offering clues and validation of the influence of multiple external stimuli on hydraulic forces that in turn alter turgor pressure. The current study aims to elucidate how exogenous melatonin modulates foliar nastic movements in Portulaca oleracea. Our findings indicate that melatonin functions as an intracellular hydraulic flux controller, influencing idioblast and crystal densities, as well as stomatal behaviour. Timepoint studies at specific Zeitgebers reveal that abiotic variables such as light and temperature can influence the endogenous melatonin concentration of P. oleracea. Therefore, this hormone potentially serves as an additional internal regulator of turgor pressure, influenced by both light and temperature. Thus, melatonin plays a crucial role in shaping the characteristic foliar nastic movements observed in P. oleracea, inherently tied to the circadian rhythm. Further investigation into idioblast and crystal torques, along with their angular momentum, is warranted to calculate the hydraulic forces at work in the leaf lamina. Thus the study underscores the multifaceted role of melatonin in navigating nastic movement processes through turgor pressure alterations brought about by intracellular depositions. The study in future could unravel melatonin's pleiotropic actions and the underlying mechanisms of foliar idiosyncratic nastic motions in other plant species as well. Moreover, both histology and anatomy play vital roles in the present study as it has provided visual evidence of the underlying mechanisms of foliar nastic movements in P. oleracea. Graphical Abstract

The Replicase Protein of Potato Virus X Is Able to Recognize and Trans-Replicate Its RNA Component.

The trans-replication system explores the concept of separating the viral RNA involved in the translation of the replicase protein from the replication of the viral genome and has been successfully used to study the replication mechanisms of alphaviruses. We tested the feasibility of this system with potato virus X (PVX), an alpha-like virus, in planta. A viral RNA template was designed which does not produce the replicase and prevents virion formation but remains recognizable by the replicase. The replicase construct encodes for the replicase protein, while lacking other virus-specific recognition sequences. Both the constructs were delivered into Nicotiana benthamiana leaves via Agrobacterium-mediated infiltration. Templates of various lengths were tested, with the longer templates not replicating at 4 and 6 days post inoculation, when the replicase protein was provided in trans. Co-expression of helper component proteinase with the short template led to its trans-replication. The cells where replication had been initiated were observed to be scattered across the leaf lamina. This study established that PVX is capable of trans-replicating and can likely be further optimized, and that the experimental freedom offered by the system can be utilized to delve deeper into understanding the replication mechanism of the virus.

Genetic Transformation of Triticum dicoccum and Triticum aestivum with Genes of Jasmonate Biosynthesis Pathway Affects Growth and Productivity Characteristics.

The transformation protocol based on the dual selection approach (fluorescent protein and herbicide resistance) has been applied here to produce transgenic plants of two cereal species, emmer wheat and bread wheat, with the goal of activating the synthesis of the stress hormone jasmonates by overexpressing ALLENE OXIDE SYNTHASE from Arabidopsis thaliana (AtAOS) and bread wheat (TaAOS) and OXOPHYTODIENOATE REDUCTASE 3 from A. thaliana (AtOPR3) under the strong constitutive promoter (ZmUbi1), either individually or both genes simultaneously. The delivery of the expression cassette encoding AOS was found to affect morphogenesis in both wheat species negatively. The effect of transgene expression on the accumulation of individual jasmonates in hexaploid and tetraploid wheat was observed. Among the introduced genes, overexpression of TaAOS was the most successful in increasing stress-inducible phytohormone levels in transgenic plants, resulting in higher accumulations of JA and JA-Ile in emmer wheat and 12-OPDA in bread wheat. In general, overexpression of AOS, alone or together with AtOPR3, negatively affected leaf lamina length and grain numbers per spike in both wheat species. Double (AtAOS + AtOPR3) transgenic wheat plants were characterized by significantly reduced plant height and seed numbers, especially in emmer wheat, where several primary plants failed to produce seeds.

A new endemic Begonia species (sect. Knesebeckia, Begoniaceae) from the south-western montane forest remnants of Ecuador

Begonia jocotocoi is a new species described from the Buenaventura Reserve in El Oro Province, south-west Ecuador. The new species morphologically resembles Begonia serotina, but differs by its minutely bullate leaf lamina (vs. smooth), the dense red long trichomes that cover the petioles and the lower surface of the leaf lamina, the latter of which distinctly become purple at maturity (vs. usually glabrous or occasionally with an indument of minute glandular white hairs and pale green below), presence of a pair of bracteoles directly beneath the pistillate flowers (vs. bracteoles absent), and the pedicels and also sometimes the abaxial surfaces of most floral whorls having a sparse cover of glandular hairs (vs. glabrous to puberulous). Photos of the new species and a distribution map are provided. Relationships with other species are discussed and the species’ preliminary conservation status is assigned as critically endangered (CR).

Net primary productivity of Betula platyphylla woodland and the response of current-year shoots to vegetation degradation in Mongolian forest steppe

At the southern margin of forest steppe vegetation in Mongolia, Betula platyphylla woodlands occur on north-facing slopes and hilltops, where congeneric shrub Betula fusca often coexists. Woodland degradation results in B. fusca scrub with scattered B. platyphylla trees. We studied the structure and productivity of a B. platyphylla woodland and the current-year shoot allometry in the Hustai National Park of central Mongolia. For the B. platyphylla woodland examined, stand basal area and estimated aboveground biomass for stems ≥ 3 cm diameter were 3.9 m2 ha–1 and 13.3 Mg dry mass ha–1, respectively. Leaf area index was 0.93 indicating open canopy layer. Aboveground net primary productivity as the sum of coarse wood production and current-year shoot mass amounted to 1.89 Mg dry mass ha–1 year–1, which was high relative to small aboveground biomass. Analysis of current-year shoot allometry demonstrated that B. platyphylla had more xeromorphic shoots in the scrub, with smaller specific leaf area, lower mass ratio of leaf laminae to supporting parts, and smaller lamina mass against the sum of petiole basal area, than in the woodland. Our results indicate that current-year shoot allometry characterizes tree response to woodland degradation at the dry margin of forest steppe.

Micromorphological and Phytochemical Evaluation of Heliotropium rariflorum Stocks From Karak, Pakistan.

Micromorphological and phytochemical studies play a major role in quality control and standardization of traditional or herbal medications. In the present research, micromorphological assessment of Heliotropium rarifloum stocks was performed through light and scanning electron microscopies (LM & SEM). The anatomy of leaves, stem and root showed salient histological features. Both surfaces of the leaves had setose glandular trichomes measuring 20-38 × 6-15 µm. The lower epidermis had comparatively a maximum anomocytic stomata (16-35) and stomatal index (12-33). The mature pollen grains were small (74 µm) and spheroidal shaped, with psilate exine (2 μm) sculpturing. Vein termination and vein islet number of the upper epidermis were 5-20 and 5-15, respectively. The palisade ratio of the leaf lamina for the upper and lower epidermis was 2-10 and 2-8. LM and SEM of the powdered samples displayed crystals, phloem fibers, xylem, vessels, sieve tube elements, companion cells, and tracheids. Extractive values determination, fluorescence, and phytochemical analysis were employed for quality control according to the World Health Organization (WHO) guidelines. Phytochemical screening revealed various secondary metabolites. It is suggested that H. rariflorum might be a reliable source of nutrients and secondary metabolites and might be more medically effective. The current findings confirm its standardization and validation.

Evaluation of Acid Lime (Citrus aurantifolia Swingle) Genotypes for Growth, Yield and Quality Traits

A study on evaluation of acid lime genotypes for growth, yield and quality traits was carried out at Citrus Research Station, Vannikonenthal, Manur Taluk and Tirunelveli district, Tamil Nadu during the year 2021–2023. Twenty five acid lime genotypes were selected for the experiment. Observation on quantitative traits such as tree height (m), tree spread (m), canopy spread (m2), tree girth (cm), leaf lamina length (mm), number of fruits/tree, mean fruit weight (g), fruit length (cm), fruit girth (cm), fruit volume (cc), number of seeds per fruit, yield/tree (kg) and qualitative traits such as total soluble solids (°Brix), acidity (%), juice content (ml), fruit juice percentage (%) and ascorbic acid content (mg/100g) were recorded. The present study results revealed that genotype SCA 19 recorded the highest values for the traits such as tree height (3.49 m), tree spread (3.58 m2 E-W; 3.74 m2 N-S), canopy spread (6.57 m3), leaf lamina length (58.40 mm) and tree girth (13.66 cm). However, genotype SCA 06 registered the lowest tree spread character. In the case of yield traits, genotype SCA 19 registered the highest values in number of fruits per tree (1080), mean fruit weight (58.75 g), yield per tree (57.89 kg per tree), number of seeds (9.10), fruit length (8.50 cm), fruit girth (4.90 cm) and fruit volume (54.81 cc). Regarding quality traits, SCA 19 observed the highest values viz., TSS (6.71˚Brix), acidity (6.78 %), ascorbic acid content (26.50 mg/100 g), fruit juice percentage (52.1 %) and juice content (46.0 ml). Hence, acid lime genotype SCA 19 recommended for further evaluation in different parts of Tamil Nadu.

Influence of air dust on anatomo-morphological and biochemical parameters of Plantago Major L

Pollution has a great impact on the environment. Plants being the representatives of autotrophic organisms are the first to face it. The photosynthesis suppression, water exchange violation, transpiration reduction, growth general oppression and plants’ development are exposed to pollutants. This causes changes in leaf coloration, necroses, premature leaf fall, changes in growth form. The effect of air dust on anatomo-morphological parameters of plantain and the effect of dust pollution on plantain’s (Plantago major L.) production processes have been studied, the dust-holding capacity of plantain leaves has been estimated. The correlation between the dust pollution level and the stomata density in the leaves’ epidermis of model species has been found out. Mass of aboveground organs (g) and leaf lamina area (cm2), the number of stomata on the leaf surface (pcs./mm2), the dust accumulation level on the leaf surface (g) have been analyzed in model species. Weighing was carried out with an accuracy of 0.001 g on electronic scales. According to the performed analysis, we have come to the conclusions: species of the plantain have 10 to 50 mg of dust particles deposited on the leaf surface, the size of leaf plates and the mass of plantain's terrestrial organs decrease as the level of air pollution increases. It should be underlined that air pollution causes an increase in the density of stomata in plantain associated with a reduction in the area of the assimilating apparatus and it can be viewed as one of the compensatory mechanisms.

Pharmacognostic, physicochemical and phytochemical profiles of Euclea divinorum (Ebenaceae)

Background: Euclea divinorum, belonging to the family Ebeneceae, has extensive traditional medicinal use in Africa. However, it lacks sufficient published data on its pharmacognostic, physicochemical, and phytochemical properties. Aims and Objectives: Thus, this study aimed at comprehensively evaluating the pharmacognostic, physicochemical, and phytochemical properties of E. divinorum using established techniques. Materials and Methods: The evaluation included assessing organoleptic properties, macroscopy, and microscopy of leaves, stems, and roots. Various physicochemical parameters, such as loss on drying and extractive values via hot and cold maceration, were determined. Phytochemical screening was also conducted on root aqueous extracts. Results and Conclusion: Results revealed specific characteristics of E. divinorum leaves, including light green coloration, distinct odor, and bitterness. Macroscopic examination highlighted opposite phyllotaxy, simple leaf types with lamina length range of 71.09 - 93.89 mm and a width range of 6.05 - 17.59 mm, obtuse leaf apexes, cuneate leaf bases, entire leaf margins, and smooth leaf surfaces. Venation displayed a reticulate pattern, with the midrib prominently visible on the lower surface. Microscopic analysis of the lower leaf epidermis showed an average of stomatal density of 3.75±0.67, epidermal density of 35.75±2.16 and stomatal index of 10.47±1.11. Microscopic examination of the leaf lamina across the midrib revealed cortical parenchymal cells containing calcium oxalate crystals, lignified xylem, and non-lignified phloem. Stem cross-sections displayed single-layered cells comprising the epidermis, secondary phloem, secondary xylem, and pith. Similar structures were observed in root cross-sections. The plant's moisture content was found to be 44.8±1.962%, with water and alcohol-soluble extractive values of 7.27±0.17 and 1.13±0.05 g/100g, respectively, through cold maceration, and 14.77±0.28 and 11.43±0.39 g/100g, respectively through hot maceration. The total ash content was measured at 3.03± 0.103%. Phytochemical screening detected various compounds, with anthraquinone glycosides, coumarine glycosides, saponin glycosides, flavonoids, proteins, and tannins being abundant. Alkaloids, cardiac glycosides, and steroids were absent. This research contributes to standardizing E. divinorum, aiding in its identification, preventing adulteration, and ensuring therapeutic efficacy.

Biochemical and gene expression profiling of oxalate biosynthesis in cherry tomato (Solanum lycopersicum var. cerasiforme) in Indo-Gangetic Plains of India

The oxalate content was assessed in nine diverse genotypes of cherry tomato in ripened fruit, leaf and root tissues. The maximum oxalate accumulation was found in leaf lamina followed by mature fruit and root tissues among all genotypes where the lowest oxalate content was found in the genotype FB-3-5 and the highest content was recorded in the genotype RSC-4. Examining the leaf and root of nine cherry tomato genotypes at three developmental stages, the investigation into the biosynthesis of oxalates focused on the study of two enzymes, glycolate oxidase (GLO) and ascorbate peroxidase (APX). A positive correlation was observed between oxalate formation and enzyme specific activity of both enzymes. Examining the relative gene expression of oxalate biosynthesizing genes, SlGLO2 and SlAPX7, indicated that the gene SlGLO2 encoded the GLO enzyme and played a crucial role in oxalate biosynthesis in cherry tomatoes. Understanding oxalate biosynthetic pathways and gene expression will aid in developing mechanisms to enhance cherry tomato nutritional quality and improving breeding programmes.

Antixenosis in Cultivars of Tomato against <i>Helicoverpa armigera</i> (Hubner)

This study on the effect of antixenosis in relation to resistance against Helicoverpa armigera in tomato was carried out at the Entomological Research Farm, LPU, Phagwara during 2020 and 2021. The result showed that the antixenosis effect of four tomato cultivars on plant morphological characters revealed that Rahul cultivar with maximum trichome density in lamina (181 and 183 cm-2), vein (89 and 93 cm), trichome length (132.43 and 136.21 µm) and leaf lamina thickness (0.21 and 0.23 mm). Correlation analysis between morphological character and larval incidence revealed significant negative correlation with trichome density (lamina and vein), trichome length, leaf area and leaf lamina thickness.

STUDY ON ANATOMICAL CHARACTERIZATIONOF EXOTIC SPECIES AMHERSTIA NOBILIS WALL

Amherstia nobilis, known as the Pride of Burma and colloquially referred to as Simshipa-vriksham, is a remarkable and rare tropical tree celebrated in Indian mythology, especially within the context of the epic Ramayana. Often dubbed the Queen of Flowering Trees. The species was named in honour of Lady Sarah Amherst, an early collector of Asian plants, and it stands as the sole representative of its genus. This study involves microscopic examination of various parts of the plant, revealing intricate details about its cellular structure, vascular arrangements, and overall morphology. Mature leaves of A. nobilis, for instance, have been analyzed micro-morphologically, with an average leaf area calculated. The leaves are characterized by numerous rubiaceous stomata, as hypostomatic. In the leaf midrib, the vascular area appears oval and vascular elements are U-shaped. The leaf lamina flanked by highly cutinized upper and lower epidermis layers. The palisade tissue is bi-layered, while the lower leaf lamina features loosely packed spongy layers with numerous vein bundles and large air spaces and contains starch grains. Histological examination of the rachis reveals an oval shape with a slightly thick-walled epidermis and hypodermis containing air cavities. The vascular region is well-differentiated withxylem elements in linear multiples. The secondary phloem elementspossess numerous prismatic crystals and patches of phloem fibers. In the mature stem, periderm formation, with a highly reduced cortical region containing chlorenchymatous cells. The vascular region comprises phloem tissues with patches of phloem fibers. The xylem is with large vessels arranged in linear multiples. The pith is highly reduced with included phloem elements. Wood anatomy reveals the vessels displaying paratracheal parenchyma distribution, appearing as aliform or eyelet type. The vessel elements are arranged in linear multiples, and the radial longitudinal section shows large vessel elements with bordered pits separated by end plates. The bark showed uni- and multi-seriate ray cells, long and narrow phloem parenchyma, and prismatic crystal deposits in phloem ray-parenchyma cells. The parenchyma cells are traversed by numerous phloem fibers, with starch granules deposited in phloem parenchyma. In conclusion, Amherstia nobilis, the Pride of Burma, exemplifies a unique combination of aesthetic appeal and complex anatomical structure, making it a subject of significant interest in botanical and horticultural research. Detailed histological and anatomical studies provide crucial insights into the species unique adaptations and structural features, underscoring the need for continued conservation efforts to protect this majestic and rare tropical tree.

Molecular Characterization and Pathogenicity of Groundnut Bud Necrosis Virus (Orthotospovirus arachinecrosis) Inducing Necrosis in Black Gram

Orthotospovirus arachinecrosis commonly known as Groundnut bud necrosis virus (GBNV), is the causal agent for necrosis disease in black gram. GBNV is the second most important challenge to black gram production in major growing areas following yellow mosaic disease. Symptoms of necrosis disease of black gram include severe downward curling and twisting of leaf lamina, veinal necrosis, petiole necrosis, bud necrosis, and necrotic streaks on the stem. Infection at early growth stages of black gram leads to plant death, while surviving plants exhibited stunted growth with a significant reduction in pod yield. The GBNV-BG isolate was maintained in pure form on cowpea cv. C-152, resulted in chlorotic and necrotic local lesions on primary leaves at seven days post-inoculation. The pathogenicity of GBNV on black gram (LBG-645) was further confirmed by artificial sap inoculation. Amplification of the coat protein gene of GBNV was confirmed through RT-PCR using gene-specific primers, producing an amplicon of 800 bp. Sequence analysis of the coat protein gene revealed that the present study isolates OQ683310 and OR295403 shared sequence identity of 98.0 % and 99.3 % respectively at the nucleotide level, with other isolates in the NCBI database. The phylogenetic analysis of the coat protein gene revealed that the isolates under this study were closely linked with the GBNV tomato isolate from Tamil Nadu (MN718651 and MZ505083).

Agronomic biofortification of finger millet for zinc, and its influence on yield and partitioning of zinc, iron, and calcium in the plant

Zinc (Zn) deficiency in humans is the most common, and zinc requirement is catered mainly by cereal food grains which have lower zinc content. Finger millet is one of the staple food crops in Africa and India and has only 25 to 30 µg Zn g−1 of grain. Breeding efforts have improved the grain-Zn content to nearly 40 µg g−1 of grain, which is far below the recommended dietary allowance of 15 mg day−1 adult−1, and such varieties are not suited to all the finger millet cultivation regions. Therefore, the objective of the present studies is to enhance the grain-Zn content of locally adapted varieties through agronomic biofortification, which can be adapted for any variety and region. The easy, promising, and cost-effective approach is the soil or foliar application of zinc to increase the grain-Zn content. Present studies over four years revealed that the foliar application of 0.5% ZnSO4·7H2O solution at flowering and 20 days after flowering (DAF) is apt to increase the grain-Zn significantly to 40 µg g−1 of grain. Whereas the soil application of ZnSO4·7H2O at 12.5 kg ha−1 is appropriate to increase the grain yield to 504 g m−2 from 444 g m−2 in the control. The partitioning of zinc and calcium was higher toward the leaf sheath, leaf lamina, and husk than the other plant parts, whereas iron was toward the root. Therefore, the translocation of zinc from leaves to grain needs to be improved for further increase in grain-zinc of finger millet.

Unraveling space and time variability in maximum water storage among sunflower organs: Implications for wetness duration

Vegetation wetness significantly alters the plant microclimate, thereby influencing plant functionality, growth, and yield. Prolonged wetness periods can exacerbate the risk of attack of various plant diseases. Maximum water storage capacity is a crucial parameter for modeling wetness duration, as it sets the upper limit for free water available for evaporation. This study aimed to achieve three main goals: (i) to investigate the maximum water storage capacity of distinct sunflower organs (leaves, stems, and capitula) and their constituent phytoelements, (ii) to establish relationships between maximum water storage and visible morphological characteristics, and (iii) to assess the impact of maximum water storage on phytoelement wetness duration. Morphological and micrometeorological measurements were conducted within a sunflower field plot. Maximum water storage capacity was determined in the laboratory using phytoelements collected from the field. For the capitula and its constituent phytoelements, this capacity was monitored throughout their development. Phytoelement size and orientation were quantified and correlated with their water storage capacity. The influence of phytoelement maximum water storage on wetness duration was investigated through simulation. Notably, we found that the maximum water storage capacity in leaf axils exceeded those in leaf lamina by 43 times. During the flowering and grain-filling stages, capitula exhibited greater water storage, primarily attributed to the contribution from the capitulum front. The area of leaves, stems, and capitula during the flowering stage had a greater impact on their maximum water storage capacity than their orientation. Simulation results revealed that certain phytoelements (e.g., leaf axils and capitulum disk) could remain wet for up to 20 h after most of the canopy, mainly leaves and stems, had dried. This study underscores the importance of examining variability in maximum water storage capacity and its impact on wetness duration within a sunflower canopy at the phytoelement level.

Spring buds of European woody plants have old 14C age

Trees and shrubs maintain carbon reserves to support their functions during periods when metabolic demand exceeds carbon supply, such as during the dormant season. To gain a better understanding of carbon storage and utilisation dynamics of eight woody plant species in temperate Central Europe, bud scale and leaf samples were collected to determine the radiocarbon age of fresh sprouts in trees and shrubs, at three background sites avoiding local emissions that may influence affect the observed 14C/12C ratio. The accelerator mass spectrometry-based bomb-radiocarbon approach, to determine the age of the mobilized carbon in the plant bud samples from storage, was complemented by stable carbon isotope measurements. The bomb-radiocarbon dating technique was used to determine the age of the samples, while a northern hemispheric atmosphere 14CO2 dataset was used to calibrate the radiocarbon ages of the plant samples. The youngest observed calibrated radiocarbon age of the buds was over 4 years, and the oldest was even 9 years old. There was no significant difference between the ages of bud scales and embryonal leaf laminas. Our results show that there is a considerable amount of stored older carbon in the woody stems that can be used to produce buds in spring, which is a complex mixture of stored carbon of different ages, but there is no relationship between the radiocarbon age and the stable carbon isotope composition. The observed results show that not only the tree species, but shrubs also can store and use significantly older carbon pools, the carbon storage intensity is similar for trees with trunks and short-stemmed shrubs branching directly above the ground, i.e. carbon storage starts in young twigs and continues in ageing branches.

Effect of High Salt Stress on Germination and Growth of Some Varieties of Common Beet

Information is provided on soil salinization as the most common abiotic stress that reduces the productivity and quality of agricultural plants. Salt stress is associated with lipid peroxidation in cell membranes, DNA damage, protein denaturation, carbohydrate oxidation, pigment breakdown and disruption of enzymatic activity, as well as metabolic adaptations, including primarily the accumulation of osmolytes. The growth of higher plants in saline soil depends on the salt tolerance of the plant species. Reduced plant growth due to salinity includes a reduction in plant leaf area. A pot experiment plant materials was carried out based on investigate the effect of salt stress on growth and state stomatal of three sugar beet (Beta vulgaris) cultivars, Cooper, Tarifa and Taltos which import from Denmark. Plants were harvested after 30, 45 and 60 days of salt treatment and were separated into leaf lamina, petioles, stem, and roots.

Genetically correlated leaf tensile and morphological traits are driven by growing season length in a widespread perennial grass.

Leaf tensile resistance, a leaf's ability to withstand pulling forces, is an important determinant of plant ecological strategies. One potential driver of leaf tensile resistance is growing season length. When growing seasons are long, strong leaves, which often require more time and resources to construct than weak leaves, may be more advantageous than when growing seasons are short. Growing season length and other ecological conditions may also impact the morphological traits that underlie leaf tensile resistance. To understand variation in leaf tensile resistance, we measured size-dependent leaf strength and size-independent leaf toughness in diverse genotypes of the widespread perennial grass Panicum virgatum (switchgrass) in a common garden. We then used quantitative genetic approaches to estimate the heritability of leaf tensile resistance and whether there were genetic correlations between leaf tensile resistance and other morphological traits. Leaf tensile resistance was positively associated with aboveground biomass (a proxy for fitness). Moreover, both measures of leaf tensile resistance exhibited high heritability and were positively genetically correlated with leaf lamina thickness and leaf mass per area (LMA). Leaf tensile resistance also increased with the growing season length in the habitat of origin, and this effect was mediated by both LMA and leaf thickness. Differences in growing season length may promote selection for different leaf lifespans and may explain existing variation in leaf tensile resistance in P. virgatum. In addition, the high heritability of leaf tensile resistance suggests that P. virgatum will be able to respond to climate change as growing seasons lengthen.