Juglandaceae
Lawsonia Plant
Calendula
Coupling sap flow velocity and amino acid concentrations as an alternative method to (15)N labeling for quantifying nitrogen remobilization by walnut trees. (1/72)
The temporal dynamics of N remobilization was studied in walnut (Juglans nigra x regia) trees growing in sand culture. Trees were fed with labeled N ((15)N) during 1999 and unlabeled N in 2000. Total N and (15)N contents in different tree compartments were measured during 80 d after bud burst and were used to estimate N remobilization for spring growth. The seasonal (and occasionally diurnal) dynamics of the concentration and (15)N enrichment of the major amino acids in xylem sap were determined concurrently. Sap flow velocity was also measured for sample trees. A new approach coupling amino acid concentrations to sap flow velocity for quantifying N remobilization was tested. A decrease of the labeled N contents of medium roots, tap roots, and trunk was observed concurrently to the increase in the labeled N content of new shoots. Remobilized N represented from previous year storage 54% of N recovered in new shoots. Arginine, citruline, gamma-amino butyric acid, glutamic acid, and aspartic acid always represented around 80% of total amino acid and amide N in xylem sap and exhibited specific seasonal trends and significant diurnal trends. N translocation was mainly insured by arginine during the first 15 d after bud burst, and then by glutamic acid and citruline. The pattern of N remobilization estimated by the new approach was consistent with that measured by the classical labeling technique. Implications for quantifying N remobilization for large, field-growing trees are discussed. (+info)Effect of local irradiance on CO(2) transfer conductance of mesophyll in walnut. (2/72)
The acclimation responses of walnut leaf photosynthesis to the irradiance microclimate were investigated by characterizing the photosynthetic properties of the leaves sampled on young trees (Juglans nigraxregia) grown in simulated sun and shade environments, and within a mature walnut tree crown (Juglans regia) in the field. In the young trees, the CO(2) compensation point in the absence of mitochondrial respiration (Gamma*), which probes the CO(2) versus O(2) specificity of Rubisco, was not significantly different in sun and shade leaves. The maximal net assimilation rates and stomatal and mesophyll conductances to CO(2) transfer were markedly lower in shade than in sun leaves. Dark respiration rates were also lower in shade leaves. However, the percentage inhibition of respiration by light during photosynthesis was similar in both sun and shade leaves. The extent of the changes in photosynthetic capacity and mesophyll conductance between sun and shade leaves under simulated conditions was similar to that observed between sun and shade leaves collected within the mature tree crown. Moreover, mesophyll conductance was strongly correlated with maximal net assimilation and the relationships were not significantly different between the two experiments, despite marked differences in leaf anatomy. These results suggest that photosynthetic capacity is a valuable parameter for modelling within-canopies variations of mesophyll conductance due to leaf acclimation to light. (+info)Four new diarylheptanoids from the roots of Juglans mandshurica. (3/72)
Four new diarylheptanoids (1-4), along with two known tetralones (5, 6), were isolated from the roots of Juglans mandshurica and their structures were elucidated on the basis of spectroscopic studies. (+info)Periods of organogenesis in mono- and bicyclic annual shoots of Juglans regia L. (Juglandaceae). (4/72)
The organogenetic cycle of shoots on main branches of 4-year-old Juglans regia trees was studied. Mono- and bicyclic floriferous and vegetative annual shoots were analysed. Five parent annual shoot types were sampled between October 1992 and August 1993. Organogenesis of summer growth units was monitored between 16 Jun. and 3 Aug. 1993. Variations over time in the number of nodes, cataphylls and embryonic green leaves of terminal buds were studied. The number of nodes of parent shoot buds was compared with the number of nodes of shoots derived from parent shoot buds. The spring growth units of mono- and bicyclic shoots consist exclusively of preformed leaves which were differentiated, respectively, during the spring flush of growth (mid-April until mid-May) or the summer flush of growth (mid-June until early August) in the previous growing season. Thus, winter buds may consist of flower and leaf primordia differentiated in two different periods during annual shoot extension. The summer growth units of bicyclic shoots consist of preformed leaves that were differentiated in spring buds during the spring flush of growth in the current growing season. Bud morphology is compared between spring and summer shoots. (+info)Genotypic differences in branching pattern and fruiting habit in common walnut (Juglans regia L.). (5/72)
Architectural analysis of 840 Slovenian walnut (Juglans regia L.) genotypes was performed to determine the most typical and frequent morphological types and to evaluate their vegetative and generative potential. Four branching and fruiting patterns (I-IV) were detected. A 3-year-old fruiting branch, consisting of a 3-year-old shoot plus corresponding 2-year-old and 1-year-old shoots, was used as a structural unit for quantitative analysis. In the intermediate fruit-bearing types with mesotonic and acrotonic branching pattern (types II and III), the total lengths of 3-, 2- and 1-year-old shoots were 385 and 380 cm, respectively, compared with 275 and 253 cm in the terminal and lateral-fruiting types (types I and IV). In type I, 1-year-old shoots had significantly fewer nodes than in other types. In addition, they had a thinner basal diameter than types III and IV, and their angles were the most erect (39 degrees ). Only 0.4 out of 3.6 1-year-old shoots were flowering with one mixed bud with 1.9 female flowers. In type IV, 2-year-old shoots had significantly more nodes and a larger basal diameter than other types. One-year-old shoots in type IV are thicker than those in other types. Ratios between the number of flowering and the total number of 1-year-old shoots were 0.7 in type IV, 0.6 in type III, 0.5 in type II and 0.1 in type I. On 1-year-old shoots in type IV, 1.7 mixed buds with a mean of three female inflorescences per bud were counted. Consequently, the generative potential is highest in type IV and lowest in type I. In types II and III, growth and the ability to bear fruits are more balanced. (+info)Anti-complement activity of constituents from the stem-bark of Juglans mandshurica. (6/72)
Four known flavonoids and two galloyl glucoses isolated from the stem-bark of Juglans mandshurica (Juglandaceae), namely taxifolin (1), afzelin (2), quercitrin (3), myricitrin (4), 1,2,6-trigalloylglucose (5), and 1,2,3,6-tetragalloylglucose (6), were evaluated for their anti-complement activity against complement system. Afzelin (2) and quercitrin (3) showed inhibitory activity against complement system with 50% inhibitory concentrations (IC(50)) values of 258 and 440 microM. 1,2,6-Trigalloylglucose (5) and 1,2,3,6-tetragalloylglucose (6) exhibited anti-complement activity with IC(50) values of 136 and 34 microM. In terms of the evaluation of the structure-activity relationship of 3,5,7-trihydroxyflavone, compounds 2, 3, and 4 were hydrolyzed with naringinase to give kaempferol (2a), quercetin (3a), and myricetin (4a) as their aglycones, and these were also tested for their anti-complement activity. Of the three aglycones, kaempferol (2a) exhibited weak anti-complement activity with an IC(50) value of 730 microM, while quercetin (3a) and myricetin (4a) were inactive in this assay system. Among the compounds tested, 1,2,3,6-tetragalloylglucose (6) showed the most potent anticomplement activity (IC(50), 34 microM). (+info)Plasma membrane aquaporins are involved in winter embolism recovery in walnut tree. (7/72)
In perennial plants, freeze-thaw cycles during the winter months can induce the formation of air bubbles in xylem vessels, leading to changes in their hydraulic conductivity. Refilling of embolized xylem vessels requires an osmotic force that is created by the accumulation of soluble sugars in the vessels. Low water potential leads to water movement from the parenchyma cells into the xylem vessels. The water flux gives rise to a positive pressure essential for the recovery of xylem hydraulic conductivity. We investigated the possible role of plasma membrane aquaporins in winter embolism recovery in walnut (Juglans regia). First, we established that xylem parenchyma starch is converted to sucrose in the winter months. Then, from a xylem-derived cDNA library, we isolated two PIP2 aquaporin genes (JrPIP2,1 and JrPIP2,2) that encode nearly identical proteins. The water channel activity of the JrPIP2,1 protein was demonstrated by its expression in Xenopus laevis oocytes. The expression of the two PIP2 isoforms was investigated throughout the autumn-winter period. In the winter period, high levels of PIP2 mRNA and corresponding protein occurred simultaneously with the rise in sucrose. Furthermore, immunolocalization studies in the winter period show that PIP2 aquaporins were mainly localized in vessel-associated cells, which play a major role in controlling solute flux between parenchyma cells and xylem vessels. Taken together, our data suggest that PIP2 aquaporins could play a role in water transport between xylem parenchyma cells and embolized vessels. (+info)A simple method to estimate photosynthetic radiation use efficiency of canopies. (8/72)
BACKGROUND AND AIMS: Photosynthetic radiation use efficiency (PhRUE) over the course of a day has been shown to be constant for leaves throughout a general canopy where nitrogen content (and thus photosynthetic properties) of leaves is distributed in relation to the light gradient. It has been suggested that this daily PhRUE can be calculated simply from the photosynthetic properties of a leaf at the top of the canopy and from the PAR incident on the canopy, which can be obtained from weather-station data. The objective of this study was to investigate whether this simple method allows estimation of PhRUE of different crops and with different daily incident PAR, and also during the growing season. METHODS: The PhRUE calculated with this simple method was compared with that calculated with a more detailed model, for different days in May, June and July in California, on almond (Prunus dulcis) and walnut (Juglans regia) trees. Daily net photosynthesis of 50 individual leaves was calculated as the daylight integral of the instantaneous photosynthesis. The latter was estimated for each leaf from its photosynthetic response to PAR and from the PAR incident on the leaf during the day. KEY RESULTS: Daily photosynthesis of individual leaves of both species was linearly related to the daily PAR incident on the leaves (which implies constant PhRUE throughout the canopy), but the slope (i.e. the PhRUE) differed between the species, over the growing season due to changes in photosynthetic properties of the leaves, and with differences in daily incident PAR. When PhRUE was estimated from the photosynthetic light response curve of a leaf at the top of the canopy and from the incident radiation above the canopy, obtained from weather-station data, the values were within 5 % of those calculated with the more detailed model, except in five out of 34 cases. CONCLUSIONS: The simple method of estimating PhRUE is valuable as it simplifies calculation of canopy photosynthesis to a multiplication between the PAR intercepted by the canopy, which can be obtained with remote sensing, and the PhRUE calculated from incident PAR, obtained from standard weather-station data, and from the photosynthetic properties of leaves at the top of the canopy. The latter properties are the sole crop parameters needed. While being simple, this method describes the differences in PhRUE related to crop, season, nutrient status and daily incident PAR. (+info)"Juglans" is a term used in botanical nomenclature, specifically for the genus of plants that includes walnut trees. The Juglans genus belongs to the family Juglandaceae and contains around 21 species of deciduous trees and shrubs, which are native to North and South America, southern Europe, and southern Asia.
The most commonly known species in this genus is Juglans regia, which is the Persian walnut or English walnut. Other notable species include the black walnut (Juglans nigra), the butternut (Juglans cinerea), and the white walnut or butterball (Juglans alba).
The name "Juglans" comes from the Latin words "jugum," meaning yoke, and "lans," meaning lance, which refers to the shape of the seed's kernel. The fruit of Juglans species is a nut that is encased in a hard, thick shell, surrounded by a fleshy husk.
While "Juglans" itself is not a medical term, various parts of Juglans trees have been used in traditional medicine and may have potential health benefits. For example, walnut leaves and bark have been used to treat skin conditions, diarrhea, and inflammation. However, it's important to note that the scientific evidence supporting these uses is limited, and further research is needed before any definitive medical claims can be made.
Juglandaceae is not a medical term, but a taxonomic category in botany. It refers to the family of flowering plants that includes walnuts, pecans, hickories, and wingnuts. These trees and shrubs are characterized by their compound leaves, distinctive fruits, and unique wood anatomy.
While not directly related to medical terminology, some plants in this family have medicinal uses. For example, the bark of black walnut (Juglans nigra) has been used traditionally as a laxative and to treat skin conditions. However, it's important to note that self-treatment with plant extracts can be dangerous and should only be done under the guidance of a healthcare professional.
Tetralones are not a medical term, but rather a chemical classification. They refer to a class of organic compounds that contain a tetralone ring structure, which is a cyclohexanone fused to a benzene ring. These compounds have various applications in the pharmaceutical industry as intermediates in the synthesis of drugs. Some tetralones have been studied for their potential medicinal properties, such as anti-inflammatory and analgesic effects, but they are not themselves approved medical treatments.
I'm sorry for any confusion, but "Plant Bark" is not a term with a specific medical definition. In general, the bark refers to the outermost covering of a tree or other plant, which serves as protection and provides a barrier against external threats. It is composed of layers including the inner bark (phloem), which transports nutrients throughout the plant, and the outer bark (periderm), which is made up of dead cells that form a protective layer.
While some plants or plant parts do have medicinal properties and are used in various forms of traditional or alternative medicine, "Plant Bark" by itself does not have any specific medical connotations. If you're referring to a specific type of plant bark with potential medicinal uses, please provide more details so I can give a more accurate response.
I'm sorry for any confusion, but "Lawsonia plant" is not a recognized medical term. Lawsonia inermis, also known as the henna plant, is sometimes used in traditional medicine and body adornment, but it is not a term that would be found in a standard medical dictionary or resource.
The Lawsonia plant contains lawsone, a natural dye that has been used for centuries to stain skin, hair, nails, and wool a reddish-brown color. In some traditional medicine systems, Lawsonia inermis is used as a remedy for conditions such as headache, fever, burns, and skin diseases. However, it's important to note that the use of Lawsonia inermis as a medical treatment has not been widely studied in clinical trials, and its effectiveness and safety are not established by modern medical research.
If you have any questions about the use of Lawsonia inermis or other natural products in medicine, I would recommend consulting with a qualified healthcare provider who can provide guidance based on your individual health needs and circumstances.
Calendula, also known as pot marigold (Calendula officinalis), is a plant that is part of the Asteraceae/Compositae family. It is often used in herbal medicine and has been utilized for various medicinal purposes due to its anti-inflammatory, antimicrobial, and antioxidant properties. Calendula extracts or ointments are sometimes applied topically to help heal wounds, burns, rashes, and other skin irritations. However, it's essential to consult a healthcare professional before using calendula for medicinal purposes, as it may interact with certain medications or have adverse effects in some individuals.
'Salvia officinalis', also known as garden sage or common sage, is not a medical condition but an herb that has been used in traditional medicine. Here's the botanical definition:
Salvia officinalis, commonly known as sage, garden sage, or common sage, is a perennial, evergreen subshrub, with woody stems, grayish leaves, and blue to purplish flowers. It belongs to the Lamiaceae family, also known as the mint family. The plant is native to the Mediterranean region and has been cultivated throughout the world for its aromatic leaves, which are used in cooking, cosmetics, and medicinal preparations.
In traditional medicine, sage leaves have been used to treat various conditions, such as sore throats, coughs, colds, and digestive issues. However, it is essential to note that the effectiveness of sage for these uses has not been thoroughly studied in clinical trials, and its use should not replace conventional medical care. Always consult with a healthcare professional before starting any new treatment or therapy.
A plant stem is not typically defined in a medical context, but rather in the field of botany. However, I can certainly provide a general biological definition for you.
In plants, stems are organs that serve primarily as support structures, holding leaves, flowers, and fruits aloft where they can receive sunlight and exchange gases. They also act as conduits, transporting water, nutrients, and sugars made during photosynthesis between the roots and shoots of a plant.
The stem is usually composed of three main tissue systems: dermal, vascular, and ground. The dermal tissue system forms the outermost layer(s) of the stem, providing protection and sometimes participating in gas exchange. The vascular tissue system contains the xylem (which transports water and nutrients upward) and phloem (which transports sugars and other organic compounds downward). The ground tissue system, located between the dermal and vascular tissues, is responsible for food storage and support.
While not a direct medical definition, understanding the structure and function of plant stems can be relevant in fields such as nutrition, agriculture, and environmental science, which have implications for human health.