Stomata Density Research Articles

Beneficial Effect of Exogenously Applied Calcium Chloride on the Anatomy and Fast Chlorophyll Fluorescence in Rhododendron × pulchrum Leaves Following Short-Term Heat Stress Treatment

The heat tolerance of plants can be improved by using exogenous calcium chloride (CaCl2) to cope with temperature fluctuations. Since global climates continue to warm, it is important to further explore the way in which plants respond to heat stress with the use of CaCl2. We aimed to explore the effect of exogenous CaCl2 on the leaf microstructure, leaf epidermal ultrastructure, and chlorophyll a fluorescence of Rhododendron × pulchrum (R. × pulchrum) under heat stress. In the leaves of R. × pulchrum treated with exogenous CaCl2, compared to the control, the thickness of the epidermis, spongy tissues, and stomatal aperture increased, whereas the stomata density and ratio of closed/open stomata decreased. In the leaves of R. × pulchrum under heat stress conditions, compared to the control, the values of the maximal photochemical efficiency of photosystem II (Fv/Fm), the performance index on an absorption basis (PIABS), the quantum yield for the reduction of terminal electron acceptors on the acceptor side of PSI (φRo), and the energy absorbed per unit cross-section of a photosynthesizing object at the moment of achieving the fluorescence maximum (ABS/CSM) all decreased, whereas the quantum yield of the energy dissipation (φDo) increased significantly. However, these differences disappeared when R. × pulchrum was treated with exogenous CaCl2. This suggests that exogenous CaCl2 can improve the heat tolerance in R. × pulchrum by regulating the leaf anatomical structure and the behavior of epidermal cells and stomata in leaves, protecting the stability of photosystems I and II and improving the electron transfer from QA to QB. Our study could provide a theoretical basis for the breeding, further research, and utilization of Rhododendron in the context of global warming.

Ameliorative effects of foliar potassium nitrate on the growth, physiological, and stomatal properties of lettuce plants under salinity stress

The restorative effects of foliar potassium nitrate spraying on morphological, physiological, and stomata properties of salt-affected lettuce (Lactuca sativa L.) cv. Yedikule plants were investigated. Lettuce seedlings grown under saline irrigation water constituted by NaCl levels with 50, 100, 150, and 200 mM were sprayed with foliar KNO3 at 500 mg L−1 after 30-day-old plants. Salinity stress adversely influenced plant growth and physiological parameters. Fresh plant biomass, leaf area per plant, and leaf number were limited at 100 mM NaCl and above. Leaf temperature, chlorophyll content, dry matter, turgor loss, and electrolyte leakage were enhanced under saline conditions; however, salinity diminished leaf relative water content. Foliar KNO3 spraying improved the physiologic and stomata traits of salt-affected lettuce plants rather than plant growth. The electrolyte leakage was increased by increasing salinity and KNO3 spraying, whereas the relative injury was lower in the plants treated with foliar KNO3. An increase in stomata density was detected up to 100 mM NaCl, while stomata length and width were gradually decreased. Salinity and foliar KNO3 resulted in more frequent stomata number up to 100 mM NaCl, but it was surprisingly reduced at higher NaCl levels. Lettuce plants could grow up with irrigation water salinity of 100 mM and foliar KNO3 with 500 mg L−1 could regulate the adverse effects of salinity on the physiological characteristics up to 100 mM NaCl.

Diverse mangroves deviate from other angiosperms in their genome size, leaf cell size and cell packing density relationships.

While genome size limits the minimum sizes and maximum numbers of cells that can be packed into a given leaf volume, mature cell sizes can be substantially larger than their meristematic precursors and vary in response to abiotic conditions. Mangroves are iconic examples of how abiotic conditions can influence the evolution of plant phenotypes. Here, we examined the coordination between genome size, leaf cell sizes, cell packing densities and leaf size in 13 mangrove species across four sites in China. Four of these species occurred at more than one site, allowing us to test the effect of climate on leaf anatomy. We found that genome sizes of mangroves were very small compared to other angiosperms, but, like other angiosperms, mangrove cells were always larger than the minimum size defined by genome size. Increasing mean annual temperature of a growth site led to higher packing densities of veins (Dv) and stomata (Ds) and smaller epidermal cells but had no effect on stomatal size. In contrast to other angiosperms, mangroves exhibited (1) a negative relationship between guard cell size and genome size; (2) epidermal cells that were smaller than stomata; and (3) coordination between Dv and Ds that was not mediated by epidermal cell size. Furthermore, mangrove epidermal cell sizes and packing densities covaried with leaf size. While mangroves exhibited coordination between veins and stomata and attained a maximum theoretical stomatal conductance similar to that of other angiosperms, the tissue-level tradeoffs underlying these similar relationships across species and environments were markedly different, perhaps indicative of the unique structural and physiological adaptations of mangroves to their stressful environments.

Respon Morfofisiologi Tanaman Kelapa Sawit Pre Nursery pada Pemberian Kompos Kotoran Walet dan Bakteri Synechococcus sp.

The purpose of this study was to determine the effect of swallow manure and Synechococcus sp. bacteria on the morphophysiology of oil palm plants in Pre Nursery. The experiment used a factorial Randomized Block Design (RAK) and three replication. The first factor being swallow manure compost, W0 = 0 grams/plant, W1 = 100 grams/plant, W2 = 150 grams/plant, W3 = 200 grams/plant. The second factor was concentration of Synechococcus sp. Bacteria, S1 = concentration 10 ml/L, S2 = concentration 15 ml/L, S3 = concentration 20 ml/L. Parameters observed were plant height, stem diameter, the number of leaves, total chlorophyll, stomata density, stomatal opening width, and transpiration rate. Application of swallow manure compost had a significant effect on the parameters of plant height, number of leaves and total chlorophyll. Concentration of Synechococcus sp. gave a significant effect on the parameters of the transpiration rate while on morphology there was no significant effect on all parameters. The best dose of compost for plant height was 200 g of compost and 10 ml/L of bacterial concentration, while the treatment of 200 g of compost and 15 ml/L of bacterial concentration was the best dose of total chlorophyll and stomatal density parameters. Combination treatment of swallow manure compost and Synechococcus sp. gave a significant effect on the parameters of plant height, total chlorophyll and stomatal density. Keywords: Morphophysiology, Organic Fertilizer, Pre Nursery, Palm Oil, Synechococcus sp

Variations of stomata development in tea plant (Camellia sinensis) leaves in different light and temperature environments and genetic backgrounds.

Stomata perform important functions in plant photosynthesis, respiration, gas exchange, and interactions with environments. However, tea plant stomata development and functions are not known. Here, we show morphological changes during stomata development and genetic dissection of stomata lineage genes regulating stomata formation in tea developing leaves. Different tea plant cultivars displayed clear variations in the stomata development rate, density and size, which are closely related to their tolerance against dehydration capabilities. Whole sets of stomata lineage genes were identified to display predicted functions in regulating stomatal development and formation. The stomata development and lineage genes were tightly regulated by light intensities and high or low temperature stresses, which affected stomata density and function. Furthermore, lower stomatal density and larger size were observed in triploid tea varieties as compared to those in diploid plant. Key stomata lineage genes such as CsSPCHs, CsSCRM, and CsFAMA showed much lower expression levels, whereas negative regulators CsEPF1 and CsYODAs had higher expression levels in triploid than in diploid tea varieties. Our study provides new insight into tea plant stomatal morphological development and the genetic regulatory mechanisms on stomata development under abiotic stresses and genetic backgrounds. The study lays a foundation for future exploring of the genetic improvement of water use efficiency in tea plants for living up to the challenge of global climate change.

Simulated Analysis of Influence of Changes in H+-ATPase Activity and Membrane CO2 Conductance on Parameters of Photosynthetic Assimilation in Leaves.

Photosynthesis is an important process in plants which influences their development and productivity. Many factors can control the efficiency of photosynthesis, including CO2 conductance of leaf mesophyll, which affects the CO2 availability for Rubisco. It is known that electrical stress signals can decrease this conductance, and the response is probably caused by inactivation of H+-ATPase in the plasma membrane. In the current work, we analyzed the influence of both CO2 conductance in the plasma membrane, and chloroplast envelopes and H+-ATPase activity on photosynthetic CO2 assimilation, using a two-dimensional mathematical model of photosynthesis in leaves. The model included a description of assimilation on the basis of the Farquhar-von Caemmerer-Berry model, ion transport through the plasma membrane, diffusion of CO2 in the apoplast, and transport of CO2 through the plasma membrane and chloroplast envelope. The model showed that the photosynthetic CO2 assimilation rate was mainly dependent on the plasma membrane and chloroplast envelope conductance; direct influence of the H+-ATPase activity (through changes in pH and CO2/HCO3- concentration ratio) on this rate was weak. In contrast, both changes in CO2 conductance of the plasma membrane and chloroplast envelopes and changes in the H+-ATPase activity influenced spatial heterogeneity of the CO2 assimilation on the leaf surface in the simulated two-dimensional system. These effects were also observed under simultaneous changes in the CO2 conductance of the plasma membrane and H+-ATPase activity. Qualitatively similar influence of changes in the CO2 conductance of the plasma membrane and chloroplast envelopes, and changes in the H+-ATPase activity on photosynthesis were shown for two different densities of stomata in the simulated leaf; however, lowering the density of stomata decreased the assimilation rate and increased the heterogeneity of assimilation. The results of the model analysis clarify the potential influence of H+-ATPase inactivation on photosynthesis, and can be the basis for development of new methods for remote sensing of the influence of electrical signals.

Variation in leaf characters and agronomical traits of Yard-long bean genotypes between Dimocarpus longan and Psidium guajava stand

Abstract. Putra FP, Kusmiyati F, Anwar S, Widaryati, Sas MGA. 2022. Variation in leaf characters and agronomical traits of Yard-long bean genotypes between Dimocarpus longan and Psidium guajava stand. Biodiversitas 23: 5752-5758. Yard-long bean (Vigna unguiculata subs. sesquipedalis) is one of the most familiar horticulture crops. Leaf characteristics such as trichomes, stomata, and chlorophyll content correlated to other traits that influenced tolerance under sub-optimum conditions and component production traits. This study aimed to evaluate the leaf characters and agronomical traits variations of the Yard-long bean genotypes. The study was conducted by Split-plot design, with the primary factor were shading between Psidium guajava and Dimocarpus longan Lour. stand. The sub-plot was seven genotypes of Yard-long beans. Analyses were performed of multiple components, including the density of trichome, density of stomata, chlorophylls, carotenoids, nitrate reductase activity, flowering times, harvesting times, and production components under shading conditions between D. longan and P. guajava stands. The density of trichome, density of stomata, total chlorophyll, carotenoid, and Nitrate reductase activity showed the variability responses for each genotype in different shading conditions. One genotype showed early flowering in shaded conditions between D. longan than in shaded conditions between P. guajava. Two genotypes have the potential to adapt under shade conditions between D. longan. The morpho-agronomic characters that have been characterized may be used as potential donors for future hybridization programs to develop superior yard-long bean varieties.

Compositional variances in cuticular lipids of wild and domesticated barley leaves and their impact on plant-environment interactions

One of the oldest cereal crops, barley is thought to have been domesticated ∼ 8000 years ago, in the Fertile Crescent. In this study, we explored the overlooked contribution of cuticular lipid metabolism to barley domestication by comparatively characterizing wild and domesticated barley variants. We revealed substantial phenotypic variances in plants’ overall morphology and in vegetative and reproductive tissues. Multiple microscopic approaches combined with gas chromatography-mass spectrometry (GC-MS) metabolite profiling indicated that wild barley leaves are more densely covered with epicuticular waxes compared to domesticated leaves with distinct compositions, but both variants contain a similar cuticle ultrastructure. Gene expression assays corroborated these observations showing higher transcript expression of key epicuticular wax biosynthetic genes in wild barley leaves, but similar expression patterns of cutin biosynthetic genes in leaves of both cultivars. Wild barley leaves also transpired water at higher rates apparently due to higher stomata density and conductance. Previous evidence claimed that barley leaf epicuticular waxes shape the interactions with Blumeria graminis f.sp. hordei (Bgh), the causal agent of powdery mildew in barely. However, in-vivo and in-vitro inoculation assays inferred that the disparate wax content and composition in wild and domesticated leaves had no apparent effect on Bgh pre-penetration processes. Altogether, our data provide novel insight into the compositional variances in cuticular lipids of wild and domesticated barley leaves and their impact on plant-environment interactions.

Does Domestication Affect Structural and Functional Leaf Epidermal Traits? A Comparison between Wild and Cultivated Mexican Chili Peppers (Capsicum annuum).

During domestication, lineages diverge phenotypically and genetically from wild relatives, particularly in preferred traits. In addition to evolutionary divergence in selected traits, other fitness-related traits that are unselected may change in concert. For instance, the selection of chili pepper fruits was not intended to change the structure and function of the leaf epidermis. Leaf stomata and trichome densities play a prominent role in regulating stomatal conductance and resistance to herbivores. Here, we assessed whether domestication affected leaf epidermis structure and function in Capsicum annuum. To do this, we compared leaf stomata and trichome densities in six cultivated varieties of Mexican Capsicum annuum and their wild relative. We measured stomatal conductance and resistance to herbivores. Resistance to (defense against) herbivores was measured as variation in the herbivory rate and larvae mortality of Spodoptera frugiperda fed with leaves of wild and cultivated plants. As expected, the different varieties displayed low divergence in stomatal density and conductance. Leaf trichome density was higher in the wild relative, but variation was not correlated with the herbivory rate. In contrast, a higher mortality rate of S. frugiperda larvae was recorded when fed with the wild relative and two varieties than larvae fed with four other varieties. Overall, although domestication did not aim at resistance to herbivores, this evolutionary process produced concerted changes in defensive traits.

Paclobutrazol Improves The Agronomic Performance and Micromorphological Profile of Five Local Black Rice ( Oryza sativa L.) Varieties in Central Java Indonesia

Local black rice (Oryza sativa L.) is one of the biodiversity of rice in Indonesia, which has tall stature and long cultivation period, easy to lodge, and requires more intensive care. Paclobutrazol (PBZ) is a plant growth inhibitor compound that could reduce plant height and accelerate plants entering the generative phase. This study aimed to determine the effects of PBZ concentration on the agronomic character and micromorphological profile of five local black rice varieties. This research was conducted experimentally using a completely randomized factorial design. The first factor was the local black rice variety (Brebes, Klaten, Magelang, Pati, and Pekalongan ), while the second was PBZ concentration (0, 100, 200, and 300 ppm) with three replications. PBZ spraying was conducted in the fourth week after planting. The data obtained were analyzed using ANOVA and HSD test (α=5%). The results showed that the concentrations of PBZ 300 ppm produced the heaviest 100 grains. The Klaten variety had wide abaxial stomata, the Magelang variety had high abaxial stomata density, while the Pati variety had long abaxial stomata and heaviest 100 grains. The interaction between Brebes variety and PBZ 0 ppm produced high adaxial stomatal density, Klaten variety, and PBZ 100 ppm have vast adaxial stomatal and high abaxial trichome density. Pati variety and PBZ 0 ppm had the most tillers, while Pati variety and PBZ 100 ppm had long adaxial stomata and the most grains per panicle. The study's critical findings are that PBZ gives different micromorphology improvements and increases agronomic performance in local black rice.

Saussurea involucrata PIP2;4 improves growth and drought tolerance in Nicotiana tabacum by increasing stomatal density and sensitivity

Aquaporins, the major facilitators of water transport across membranes, are involved in growth and development and adaptation to drought stress in plants. In this study, a plasma membrane intrinsic protein (SiPIP2;4) was cloned from Saussurea involucrata, a cold-tolerant hardy herb. The expression of SiPIP2;4 increased the stomatal density and sensitivity of tobacco (Nicotiana tabacum), thus, affecting the plant’s growth and resistance to the diverse water environment. The higher stomatal density under well-watered conditions effectively promoted the photosynthetic rate, which led to the rapid growth of transgenic lines. The stomata in the transgenic lines responded more sensitively to the vapor pressure deficit than the wild-type under different levels of ambient humidity. Their stomatal apertures positively correlated with the ambient humidity. Under drought conditions, the overexpression of SiPIP2;4 promoted rapid stomatal closure, reduced water dissipation, and enhanced drought tolerance. These results indicate that SiPIP2;4 regulates the density and sensitivity of plant stomata, thus, playing an important role in balancing plant growth and stress tolerance. This suggests that SiPIP2;4 has the potential to serve as a genetic resource for crop improvement.

Stomatal and epidermal characteristics of Zingiberaceae in Serang District, Banten, Indonesia

Abstract. Windarsih G, Riastiwi I, Dewi AP. Yuriyah S. 2022. Stomatal and epidermal characteristics of Zingiberaceae in Serang District, Banten, Indonesia. Biodiversitas 23: 5373-5386. The stomatal and epidermal characteristics can be used as additional evidence in plant taxonomy activity. The aim of the study was to identify the stomatal and epidermal characteristics of Zingiberaceae in Serang District, Banten, Indonesia. The samples used were 11 species of Zingiberaceae in Serang District region. The stomatal and epidermal collection was carried out using the replica technique. Based on the results, all species has brachyparatetracytic type of stomata, on both adaxial and abaxial surfaces of the leaf. The densities of stomata of all species observed on abaxial were higher than adaxial surface of the leaf. The stomatal density on adaxial surface of leaf between 1.71-4.43 stomata per unit leaf area of 171,602 µm2, while on abaxial 10.46-42.22 stomata per unit leaf area. The stomatal index on adaxial surface is between 1.34-6.97%, while on abaxial 7.54-30.25%. The length of guard cells on adaxial surface is between 30.30-47.85 µm, while on abaxial 29.86-50.68 µm. The width of guard cells on adaxial surface between 18.67-31.73 µm, while on abaxial 19.97-31.95 µm. The adaxial epidermal cells have a column, polygonal, or rectangular shapes, while the abaxial has poligonal or rectangular-shaped epidermal cells. The epidermal cells that are over leaf veins have polygonal or rectangular-shaped cells.

Stomatal and epidermal characteristics of Zingiberaceae in Serang District, Banten, Indonesia

Abstract. Windarsih G, Riastiwi I, Dewi AP. Yuriyah S. 2022. Stomatal and epidermal characteristics of Zingiberaceae in Serang District, Banten, Indonesia. Biodiversitas 23: 5373-5386. The stomatal and epidermal characteristics can be used as additional evidence in plant taxonomy activity. The aim of the study was to identify the stomatal and epidermal characteristics of Zingiberaceae in Serang District, Banten, Indonesia. The samples used were 11 species of Zingiberaceae in Serang District region. The stomatal and epidermal collection was carried out using the replica technique. Based on the results, all species has brachyparatetracytic type of stomata, on both adaxial and abaxial surfaces of the leaf. The densities of stomata of all species observed on abaxial were higher than adaxial surface of the leaf. The stomatal density on adaxial surface of leaf between 1.71-4.43 stomata per unit leaf area of 171,602 µm2, while on abaxial 10.46-42.22 stomata per unit leaf area. The stomatal index on adaxial surface is between 1.34-6.97%, while on abaxial 7.54-30.25%. The length of guard cells on adaxial surface is between 30.30-47.85 µm, while on abaxial 29.86-50.68 µm. The width of guard cells on adaxial surface between 18.67-31.73 µm, while on abaxial 19.97-31.95 µm. The adaxial epidermal cells have a column, polygonal, or rectangular shapes, while the abaxial has poligonal or rectangular-shaped epidermal cells. The epidermal cells that are over leaf veins have polygonal or rectangular-shaped cells.

Characterization of anatomical features, developmental roadmaps, and key genes of bamboo leaf epidermis.

The exact developmental roadmaps of bamboo leaf epidermis and the regulating genes are largely unknown. In this study, we comprehensively investigated the morphological features of the leaf epidermis of bamboo, Pseudosasa japonica. We also established the developmental roadmaps of the abaxial epidermis along the linearly growing leaf. A variant of P. japonica, P. japonica var. tsutsumiana, with smaller stomata and higher stomata density, was identified. Further analysis revealed that the higher stomata density of the variant was due to the abnormal increase in stomata columns within the single stomata band. This abnormal development of stomata bands was observed as early as the guard mother cell stage in the leaf division zone (DZ). Interestingly, the developmental pattern of the single stomata was similar in P. japonica and the variant. Molecular data showed that PjDLT (Dwarf and Low Tillering) was significantly downregulated in leaves DZ of the variant. Overexpression of PjDLT in Arabidopsis and rice results in smaller plants with lower stomata density, whereas downregulation or mutation of OsDLT results in increased stomata density. Our results highlight the morphological features and developmental schedule of the leaf epidermis of bamboo and provide evidence that DLT plays an important role in regulating stomata in bamboo and rice.

Biological effects of some Colchicum autumnale L. extracts on tissue development of two varieties of Ocimum basilicum L.

Colchicum autumnale L. is a perennial herb from the Colchicaceae family with an unusual life cycle, and it is characterized by an underground corm and hypogynous flowers that appear in autumn; its medicinal importance is represented by its primary alkaloid, colchicine, which has been studied for its anti-inflammatory and antimitotic properties and used in the treatment of some diseases and artificial polyploidy induction in plants. This study aims to determine and evaluate the biological effects induced by treatment with C. autumnale extracts on tissue development in test plants, represented by two Ocimum basilicum L. varieties: ‘Italiano Classico’ and ‘Aromat de Buzău’. Morpho-anatomical observations and some biochemical and physiological analyses were employed. Results show unusual shapes of leaves, differences in stomata size and density, and heteromorphic cells in leaves and epicotyl’s structure in both studied varieties of treated basil test plants.

Effects of Shading on Anatomical Aspects and Chlorophyll and Carotenoid Contents in Paricá

Paricá (Schizolobium parahyba variety amazonicum) is an important species for reforestation programs in the Amazon; nevertheless, the anatomical and physiological parameters of the seedlings of this species under shading are not yet fully understood. This study evaluated the chlorophyll and carotenoid contents, the stomatal structure, and the stomatal position in the leaf epidermis under shading of paricá seedlings. The experiment comprised a randomized block design in a subdivided plot scheme, with two sources (Belterra and Urupá) and different shading levels (full sun, 30%, 50%, and 70%). At 100 days after sowing, we performed the analyses of photosynthetic pigment concentration and leaf anatomy. We found that the leaf is hypoestomatic with paracitic stomata and unicellular filiform trichomes on both sides. Higher levels of shading increased the contents of chlorophyll a and b and reduced the stomata density and carotenoid contents in the leaves of young paricá, showing that paricá has phenotypic plasticity to shading.

Tetraploidy induction enhances morphological, physiological and biochemical characteristics of wallflower (Erysimum cheiri (L.) Crantz)

Wallflower (Erysimum cheiri (L.) Crantz is one of the most important bedding flowers and potted plants in the floriculture industry. Its widespread cultivation is hindered due to self-incompatibility and limited breeding. The present study was conducted to investigate the effects of polyploidy induction on different characteristics of wallflower. Seeds were treated with colchicine (0, 0.5, 0.75 and 1%) (w/v) and oryzalin (0, 50, 100 and 150 mgl−1) along various exposure times (24, 36 and 48 h). The highest tetraploidy induction (53%) was seen in 150 mgl−1 oryzalin treatment for 36 h. The chromosome doubled plants indicated increase in trichome number, pollen size, stomata size and number of chloroplasts in the stomata guard cells, while stomata density and pollen number were decreased. The new tetraploid induced wallflowers showed compact growth habit with shorter internodes and roots, while leaves were bigger (60%) and purplish, flowering period was prolonged (65%), and flowers showed greater longevity (41%), diameter (47%) and number (78%), compared to diploid controls. Their anthocyanin and total soluble solids contents were increased by 56% and 140%, respectively. UPLC-MS analysis indicated that phytohormone contents of Ze, SA, JA and ABA were significantly increased in the tetraploid induced plants than diploid controls, while IAA, GA3 and BR were less accumulated. The new ornamental features developed for the first time in wallflower proves that polyploidization is a promising tool to introduce a commercial flowering pot plant cultivar and a new genetic resource for future breeding programs.

Effect of Organic Matter Fertilizers on the Composition of Volatiles, Morphometrical and Anatomical Parameters of Essential Oil-Bearing Thymus × citriodorus Cultivated in an Open Field Conditions

Thymus × citriodorus (Lamiaceae) is medicinal, essential oil-bearing hybrid, synthesizing significant amounts of geraniol. This hybrid is suitable for cultivation in an open ground in the Baltic region; therefore, increasing the yield and amounts of bioactive compounds by organic matter fertilization during organic farming is realized. The aim of the present study was to evaluate the effect of fertilization with liquid cattle dung and humus on the quantitative and qualitative composition of essential oils as well as on biomass for some morphometrical and anatomical parameters of Thymus × citriodorus that were grown in open ground for two years. Each fertilization treatment was carried out on four replications, and four separate experimental plots were used as control plots. For anatomical investigations, the impress method and light microscopy were used. The essential oils were isolated by hydrodistillation and analyzed by GC-FID and GC-MS. The results showed somewhat different effects of liquid cattle dung and humus on the investigated parameters of hybrid in the first (warmer and drier) and second (rainier and cooler) experimental years. Liquid cattle dung had positive effects on biomass, height and the area covered by plants and on the number and length of inflorescences as well as on the density of stomata in the lower epidermis in the first year, but in the second experimental year, effects were observed on the length of inflorescences only. The effect of humus on the density of glandular trichomes in the upper epidermis of leaves was positive in the first year, but negative in the second experimental year. Moreover, in the second experimental year, humus affected negatively the height of plants and the percentage of the essential oil. The conclusion was that although it is fertilized with the same organic fertilizers, different climatic conditions in different years can influence chemical, anatomical and morphometrical parameters of plants growing in an open ground.

Analogous foliar uptake and leaf-to-root translocation of micelle nanoparticles in two dicot plants of diverse families

Bio-inspired nanoparticles, including metallic, micelles, and polymeric, have been explored as a novel tool in the quest for effective and safe agrochemicals. Although nanoparticles (NPs) are being rapidly investigated for their usefulness in agricultural production and protection, little is known about the behaviour and interaction of oil-in-water micelle nanoparticles or nano-micelles (NM) with plants. We loaded a bio-based resin inherent of tree from the Pinaceae family as active material and produced stable nano-micelles using a natural emulsifier system. Here, we show that foliar-applied nano-micelle can translocate in two dicot plants belonging to diverse families (Coriandrum sativum -Apiaceae and Trigonella foenumgraecum -Fabaceae) via similar mode. Fluorescent-tagged NM (average diameter 11.20nm) showed strong signals and higher intensities as revealed by confocal imaging and exhibited significant adhesion in leaf compared to control. The NM subsequently translocates to other parts of the plants. As observed by SEM, the leaf surface anatomies revealed higher stomata densities and uptake of NM by guard cells; furthermore, larger extracellular spaces in mesophyll cells indicate a possible route of NM translocation. In addition, NM demonstrated improved wetting-spreading as illustrated by contact angle measurement. In a field bioassay, a single spray application of NM offered protection from aphid infestation for at least 9 days. There were no signs of phytotoxicity in plants post-application of NM. We conclude that pine resin-based nano-micelle provides an efficient, safe, and sustainable alternative for agricultural applications.

Induction of mutation by treatment with colchicine and spraying with progesterone for two cultivars of zinnia elegans by using DNA molecular

The study was carried out in the fields of the Department of Horticulture and Landscaping, College of Agriculture and Forestry, University of Mosul, during the agricultural season spring 2021, to study the development of the mutation by treatment with colchicine and spraying with progesterone for two cultivars of zinnia, where two cultivars of zinnia (red and white), and three concentrations of colchicine at 0, 0.05 and 0.1%, and three concentrations of progesterone, which are 0.5, 10 mg / liter. And the study of genetic markers using RAPD technology, where four primers were used. The results obtained are summered up in the occurrence of chromosomal duplication for the two cultivars, and the stomata density was affected as a result of the interaction between cultivars and colchicine, the red cultivar was superior with 0.1% colchicine significantly. And progesterone at 5 mg/L had the highest value in the stomatal area, and the triple interaction treatment between the red variety and 0.1% colchicine and 5 mg/L of progesterone produced the highest value in the stomatal density, and the highest stomatal area resulted when the triple interaction between the white variety and 0% colchicine And 5 mg/L of progesterone.