scholarly journals Changes in the distribution of endogenous hormones in Phyllostachys edulis ‘Pachyloen’ during bamboo shooting

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0241806
Author(s):  
Zhan Shen ◽  
Yan-hua Zhang ◽  
Lei Zhang ◽  
Yuan Li ◽  
Ya-dong Sun ◽  
...  
Keyword(s):  
Mass Fraction ◽  
Inverse Relationship ◽  
Shoot Growth ◽  
Zeatin Riboside ◽  
The Other ◽  
Enzyme Linked Immunosorbent Assay ◽  
Endogenous Hormones ◽  
Phyllostachys Edulis ◽  
Mass Fractions ◽  
Indole 3 Acetic Acid

In this study, we investigated the changes in the distribution and regulation of endogenous hormones in Phyllostachys edulis ‘Pachyloen’ during bamboo shooting. Enzyme-linked immunosorbent assay was used to measure the mass fractions of indole-3-acetic acid (IAA), gibberellic acid (GA), zeatin riboside (ZR), and abscisic acid (ABA) in rhizomes, shoots, and maternal bamboo organs during shoot sprouting, shoot growth, and new-bamboo formation. Measurements were compared among bamboo parts and developmental periods. The overall mass fractions of IAA and ABA were significantly higher than those of ZR and GA, driven by differences among bamboo parts and developmental periods. The abundance of each endogenous hormone varied among bamboo parts and developmental periods. During bamboo shooting, ABA had the highest mass fraction in all bamboo parts sampled, followed by IAA, GA, and ZR. Among bamboo parts, rhizomes had more IAA, ZR, and GA than the other parts, but significantly less ABA. Winter shoots had higher ZR: IAA and GA: IAA ratios than rhizomes and maternal bamboo organs. During shoot growth, ABA was the most abundant hormone in rhizomes and maternal bamboo organs, followed by IAA, ZR, and GA. In contrast, IAA was the most abundant hormone in spring shoots, followed by ABA, ZR, and GA. Maternal bamboo organs had a significantly higher ZR: GA ratio, and significantly lower IAA: ABA, ZR: ABA, and GA: ABA ratios than rhizomes. Spring shoots had significantly higher IAA: ABA, ZR: ABA, and GA: ABA ratios than rhizomes and maternal bamboo organs; significantly higher ZR mass fractions, and ZR: GA and ZR: IAA ratios and significantly lower ABA mass fractions than rhizomes; and significantly higher GA: IAA ratio than maternal bamboo organs. During new-bamboo formation, ABA was the most abundant hormone in rhizomes, winter shoots, and maternal bamboo organs, followed by IAA, ZR, and GA. Maternal bamboo organs had significantly lower IAA mass fractions and significantly higher ABA mass fractions than rhizomes and new bamboo tissue. IAA and ABA abundances exhibited an inverse relationship in rhizomes and maternal bamboo organs. GA: ABA and GA: IAA ratios decreased gradually and other hormone ratios exhibited parabolic trends over the bamboo-shooting period, with the highest ratios observed in new bamboo tissues. Overall, the coordination or antagonism among endogenous hormones plays a key regulatory role in bamboo shoot growth. The formation of thick walls in P. edulis ‘Pachyloen’, one of its major traits, may be partially attributed to the relatively high IAA and ZR and low GA mass fractions.

scholarly journals Effects of light and ethylene on endogenous hormones and development of Catasetum fimbriatum (Orchidaceae)

2006 ◽  
Vol 18 (3) ◽  
pp. 359-365 ◽  
Author(s):  
Rogério M. Suzuki ◽  
Gilberto B. Kerbauy
Keyword(s):  
Leaf Growth ◽  
Shoot Elongation ◽  
Zeatin Riboside ◽  
Endogenous Hormones ◽  
Light Conditions ◽  
Active Growth ◽  
Dark Light ◽  
The Difference ◽  
Catasetum Fimbriatum ◽  
Indole 3 Acetic Acid

This study attempted to clarify the effects of dark, light and ethylene on plant growth and endogenous levels of indole-3-acetic acid (IAA), cytokinins and abscisic acid in Catasetum fimbriatum. Dark-incubation fully inhibited root and pseudobulb formation as well as leaf growth, but favored shoot elongation. The results of continuous and active growth in dark-incubated shoots (stolons) were induced by strong apical meristem sink activity and by the significantly increased levels of cytokinins in shoots. In fact, shoot length, cytokinin and IAA levels in dark-incubated shoots were about twice as great as for those grown under light conditions. Moreover, the total cytokinin level in shoots of C. fimbriatum under light conditions without ethylene was significantly higher than that found in roots. High levels of cytokinins in dark-grown stolons may be closely related to the absence of roots in C. fimbriatum. Under light conditions, the increased IAA level in shoots is mediated by ethylene. However, ethylene caused a significant increase of cytokinins in roots of light-treated plants, which may be involved in the retardation of root growth. Since the difference of cytokinins in shoots between ethylene-treated and non-treated plants under light conditions is small, it is concluded that the marked inhibition of leaf growth in ethylene-treated plants can be attributed to ethylene. Zeatin and zeatin riboside are the major cytokinins in C. fimbriatum regardless of the light conditions, ethylene treatment or organ types.

scholarly journals Reduction of Early Fruit Abscission by Main-branch-girdling in Macadamia Is Related to the Favorable Status of Carbohydrates and Endogenous Hormones

HortScience ◽  
2022 ◽  
Vol 57 (1) ◽  
pp. 40-47
Author(s):  
Wei Hai Yang ◽  
Chao Zhong Lu ◽  
Wei Chen ◽  
Huan Yu Xu
Keyword(s):  
Acetic Acid ◽  
Fruit Set ◽  
Physiological Mechanism ◽  
Zeatin Riboside ◽  
Endogenous Hormones ◽  
Fruit Abscission ◽  
Fruit Drop ◽  
Macadamia Integrifolia ◽  
Horticultural Practice ◽  
Indole 3 Acetic Acid

Fruit abscission occurring severely in the early fruit development affects macadamia yield. Developing effective methods to improve fruit retention is a priority for macadamia cultivation and production. Girdling is an important horticultural practice that has been widely used to increase fruit yield. Previous studies have shown that girdling fails to increase macadamia yield despite enhancing the early fruit set, but few have examined the effect of girdling on its related physiological mechanism. The objective of this study was to investigate the effects of main-branch girdling (MBG) on early fruit retention and also on the levels of carbohydrates and endogenous hormones in the leaves, bearing shoots and fruit of macadamia. Herein, MBG was performed at fruit set using a single-blade knife on 9-year-old macadamia trees (Macadamia integrifolia). Results showed that MBG significantly reduced young fruit drop, concurrent with significant increases in the contents of starch in both the leaves and the bearing shoots and in glucose, fructose, and sucrose levels in the husk and seed. It was suggested that the availability of carbohydrate for fruit retention was improved by MBG. Additionally, MBG increased indole-3-acetic acid (IAA), gibberellin (GA3), and zeatin-riboside (ZR, a type of cytokinin) concentrations and decreased abscisic acid (ABA) contents in the husk and the seed, indicating that MBG reduced the early fruit drop by modifying the balance of endogenous hormones. Therefore, a positive interplay between carbohydrates and endogenous hormones induced by MBG was involved in the reduction of early fruit abscission in macadamia.

scholarly journals Leaf Trimming and High Temperature Regulation of Phytohormones and Polyamines in Creeping Bentgrass Leaves

2016 ◽  
Vol 141 (1) ◽  
pp. 66-75 ◽  
Author(s):  
Sanalkumar Krishnan ◽  
Yingmei Ma ◽  
Emily Merewitz
Keyword(s):  
Heat Stress ◽  
High Temperature ◽  
Creeping Bentgrass ◽  
Zeatin Riboside ◽  
Endogenous Hormones ◽  
Leaf Base ◽  
Leaf Tissues ◽  
Stress Susceptibility ◽  
Indole 3 Acetic Acid ◽  
Hormone Analysis

Mowing frequencies are associated with differences in disease susceptibility of turfgrasses, but how hormones respond to mowing practices are not fully understood. Two independent growth chamber experiments were conducted to determine how leaf trimming and heat stress play a role in modulating endogenous hormones within creeping bentgrass (Agrostis stolonifera) leaf tissues. The study also aimed to evaluate whether there are hormone changes at 0, 15, and 30 minutes after leaf trimming (wounding). The effects of trimming and temperature on sod plugs of creeping bentgrass ‘Penncross’ and ‘Penn-G2’ were investigated under optimal conditions (23/20 °C day/night) and heat stress (30/25 °C day/night). Plants were 1) untrimmed and sampled by plucking at the leaf base, 2) untrimmed and sampled by cutting at 0, 15, and 30 minutes, or 3) trimmed once every 3 days. Salicylic acid (SA), jasmonic acid (JA), abscisic acid (ABA), and indole-3-acetic acid (IAA) were generally greater in untrimmed plants compared with plants trimmed every 3 days under high temperature conditions. Zeatin riboside (ZR) was lower in untrimmed plants compared with plants trimmed every 3 days. JA and gibberellic acid (GA) accumulated to greater levels in the plants after 15 and 30 minutes of sampling. Polyamines (PAs) exhibited a transient increase in putrescine (Put) due to wounding. The results demonstrate the importance of research practices that consider the timing of sampling turfgrass plants for hormone analysis, help elucidate why mowing practices may play a role in stress susceptibility, and may be applicable to various studies related to leaf wounding.

scholarly journals Dynamic Changes in Endogenous Hormones in Terminal Buds from Different Crown Positions in Sequoia sempervirens (Lamb.) Endl

HortScience ◽  
2021 ◽  
pp. 1-5
Author(s):  
Shuming Ju ◽  
Lingzhen Ji ◽  
Delan Xu
Keyword(s):  
Indole Acetic Acid ◽  
Zeatin Riboside ◽  
Sequoia Sempervirens ◽  
Enzyme Linked Immunosorbent Assay ◽  
Endogenous Hormones ◽  
Dynamic Changes ◽  
Terminal Bud ◽  
Change Trend ◽  
Terminal Buds ◽  
Lateral Branches

Endogenous hormones can improve plant resistance and regulate growth and development. To obtain the basis of chemical control technology for improving Sequoia sempervirens resistance in Xuzhou, China, the current study probed the dynamic changes of endogenous hormones in terminal buds from different crown positions in S. sempervirens. Enzyme-linked immunosorbent assay (ELISA) was used to measure changes in the contents of endogenous hormones in terminal buds from the upper, middle, and lower lateral branches. The results were as follows: Indole acetic acid (IAA) in all terminal positions had a similar change trend of “rise–drop–rise.” Gibberellic acid (GA) in the upper and middle terminal buds showed similar trends of “drop–rise,” but GA in the lower lateral branches presented a “rise–drop” trend. Zeatin–riboside (ZR) in all terminal positions had similar change trends of “drop–rise.” Abscisic acid (ABA) in all terminal positions had similar change trends of “drop–rise–drop.” the trend of (IAA + GA + ZR)/ABA in all terminal positions was the same as that of IAA. Our results confirmed that, in autumn, the high content and ratio of stimulatory endogenous hormones in the terminal bud of S. sempervirens induced the terminal bud cells to continue to divide and grow, and the new branches could not be fully lignified and deeply dormant before the onset of low temperatures in winter, which led to a decrease in cold resistance and even the death of the terminal buds.

A technique for uranium and plutonium determination using coulometric potentiostatic facility UPK-19 for analysis of mixed-oxide fuel

2020 ◽  
Vol 86 (12) ◽  
pp. 15-22
Author(s):  
N. A. Bulayev ◽  
E. V. Chukhlantseva ◽  
O. V. Starovoytova ◽  
A. A. Tarasenko
Keyword(s):  
Acid Solution ◽  
Mass Fraction ◽  
Background Electrolyte ◽  
Stable State ◽  
Sulfamic Acid ◽  
Oxide Fuel ◽  
Oxidation Current ◽  
Mox Fuel ◽  
Mass Fractions ◽  
Uranium Plutonium

The content of uranium and plutonium is the main characteristic of mixed uranium-plutonium oxide fuel, which is strictly controlled and has a very narrow range of the permissible values. We focused on developing a technique for measuring mass fractions of uranium and plutonium by controlled potential coulometry using a coulometric unit UPK-19 in set with a R-40Kh potentiostat-galvanostat. Under conditions of sealed enclosures, a special design of the support stand which minimized the effect of fluctuations in ambient conditions on the signal stability was developed. Optimal conditions for coulometric determination of plutonium and uranium mass fractions were specified. The sulfuric acid solution with a molar concentration of 0.5 mol/dm3 was used as a medium. Lead ions were introduced into the background electrolyte to decrease the minimum voltage of hydrogen reduction to –190 mV. The addition of aluminum nitride reduced the effect of fluoride ions participating as a catalyst in dissolving MOX fuel samples, and the interfering effect of nitrite ions was eliminated by introducing a sulfamic acid solution into the cell. The total content of uranium and plutonium was determined by evaluation of the amount of electricity consumed at the stage of uranium and plutonium co-oxidation. Plutonium content was measured at the potentials, at which uranium remains in the stable state, which makes it possible to subtract the contribution of plutonium oxidation current from the total oxidation current. The error characteristics of the developed measurement technique were evaluated using the standard sample method and the real MOX fuel pellets. The error limits match the requirements set out in the specifications for MOX fuel. The technique for measuring mass fractions of uranium and plutonium in uranium-plutonium oxide nuclear fuel was certified. The relative measurement error of the mass fraction of plutonium and uranium was ±0.0070 and ±0.0095, respectively. The relative error of the ratio of the plutonium mass fraction to the sum of mass fractions of uranium and plutonium was ±0.0085.

scholarly journals Numerical Investigation of the Effect of Air Leaking into the Working Fluid on the Performance of a Steam Ejector

2021 ◽  
Vol 11 (13) ◽  
pp. 6111
Author(s):  
He Li ◽  
Xiaodong Wang ◽  
Jiuxin Ning ◽  
Pengfei Zhang ◽  
Hailong Huang
Keyword(s):  
Flow Structure ◽  
Mass Fraction ◽  
Internal Flow ◽  
Working Fluid ◽  
Physical Parameters ◽  
Entrainment Ratio ◽  
Air Mass ◽  
Steam Ejector ◽  
Primary Fluid ◽  
Mass Fractions

This paper investigated the effect of air leaking into the working fluid on the performance of a steam ejector. A simulation of the mixing of air into the primary and secondary fluids was performed using CFD. The effects of air with a 0, 0.1, 0.3 and 0.5 mass fraction on the entrainment ratio and internal flow structure of the steam ejector were studied, and the coefficient distortion rates for the entrainment ratios under these air mass fractions were calculated. The results demonstrated that the air modified the physical parameters of the working fluid, which is the main reason for changes in the entrainment ratio and internal flow structure. The calculation of the coefficient distortion rate of the entrainment ratio illustrated that the air in the primary fluid has a more significant impact on the change in the entrainment ratio than that in the secondary fluid under the same air mass fraction. Therefore, the air mass fraction in the working fluid must be minimized to acquire a precise entrainment ratio. Furthermore, this paper provided a method of inspecting air leakage in the experimental steam ejector refrigeration system.

Numerical and Experimental Investigation Into the Effects of Nanoparticle Mass Fraction and Bubble Size on Boiling Heat Transfer of TiO2–Water Nanofluid

2016 ◽  
Vol 138 (8) ◽  
Author(s):  
Cong Qi ◽  
Yongliang Wan ◽  
Lin Liang ◽  
Zhonghao Rao ◽  
Yimin Li
Keyword(s):  
Heat Transfer ◽  
Bubble Size ◽  
Boiling Heat Transfer ◽  
Mass Fraction ◽  
Experimental Methods ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients ◽  
Mass Fractions ◽  
Boiling Heat Transfer Coefficient ◽  
Bubble Sizes

Considering mass transfer and energy transfer between liquid phase and vapor phase, a mixture model for boiling heat transfer of nanofluid is established. In addition, an experimental installation of boiling heat transfer is built. The boiling heat transfer of TiO2–water nanofluid is investigated by numerical and experimental methods, respectively. Thermal conductivity, viscosity, and boiling bubble size of TiO2–water nanofluid are experimentally investigated, and the effects of different nanoparticle mass fractions, bubble sizes and superheat on boiling heat transfer are also discussed. It is found that the boiling bubble size in TiO2–water nanofluid is only one-third of that in de-ionized water. It is also found that there is a critical nanoparticle mass fraction (wt.% = 2%) between enhancement and degradation for TiO2–water nanofluid. Compared with water, nanofluid enhances the boiling heat transfer coefficient by 77.7% when the nanoparticle mass fraction is lower than 2%, while it reduces the boiling heat transfer by 30.3% when the nanoparticle mass fraction is higher than 2%. The boiling heat transfer coefficients increase with the superheat for water and nanofluid. A mathematic correlation between heat flux and superheat is obtained in this paper.

Effect of CeO2 addition on microstructure and tribological characteristics of laser cladded Cu10Al–MoS2 coating under oil lubrication

2021 ◽  
pp. 146442072110309
Author(s):  
Shao Lifan ◽  
Ge Yuan ◽  
Kong Dejun
Keyword(s):  
Abrasive Wear ◽  
Wear Mechanism ◽  
Mass Fraction ◽  
Friction Reduction ◽  
Depth Of Field ◽  
Oil Lubrication ◽  
Wear Properties ◽  
Fatigue Wear ◽  
Wear Rates ◽  
Mass Fractions

In order to improve the friction and wear properties of Cu10Al–MoS2 coating, the addition of CeO2 is one of the present research hot spots. In this work, Cu10Al–MoS2 coatings with different CeO2 mass fractions were successfully fabricated on Q235 steel using a laser cladding. The microstructure and phase compositions of obtained coatings were analyzed using an ultra-depth of field microscope and X-ray diffraction, respectively. The friction-wear test was carried out under oil lubrication using a ball-on-disk wear tester, and the effects of CeO2 mass fraction on the microstructure, hardness, and friction-wear properties were studied, and the wear mechanism was also discussed. The results show that the laser cladded Cu10Al–MoS2 coatings with the different CeO2 mass fractions were mainly composed of Cu9Al4, Cu, AlFe3, Ni, MoS2, and CeO2 phases. The Vickers-hardness (HV) of Cu10Al–8MoS2–3CeO2, Cu10Al–8MoS2–6CeO2, and Cu10Al–8MoS2–9CeO2 coatings was 418, 445, and 457 HV0.3, respectively, which indicates an increase in hardness with the increase of CeO2 mass fraction. The average coefficients of friction (COF) and wear rates decrease with the increase of CeO2 mass fraction, presenting the outstanding friction reduction and wear resistance performances. The wear mechanism of Cu10Al–MoS2 coatings is changed from abrasive wear with slight fatigue wear to abrasive wear with the increase of CeO2 mass fraction.

Movement of Several Herbicides Through Excised Plant Tissue

Weed Science ◽  
1970 ◽  
Vol 18 (1) ◽  
pp. 64-68 ◽  
Author(s):  
T. D. Taylor ◽  
G. F. Warren
Keyword(s):  
Acetic Acid ◽  
Phaseolus Vulgaris ◽  
Plant Tissue ◽  
The Other ◽  
Tissue Orientation ◽  
Chemical Retention ◽  
Dichlorophenoxy Acetic Acid ◽  
Indole 3 Acetic Acid

Uptake and movement of various herbicides and auxins by bean (Phaseolus vulgarisL.) petiole sections were studied. Isopropylm-chlorocarbanilate (chlorpropham) was the most mobile of the compunds studied, followed in order of decreasing mobility by: indole-3-acetic acid (IAA), 3-amino-s-triazole (amitrole), (2,4-dichlorophenoxy)acetic acid (2,4-D), 3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea (linuron), and 3-amino-2,5-dichlorobenzoic acid (amiben). Amiben immobilization may have been due to glucoside formation in the tissues. IAA was rapidly transported through basipetally but not acropetally oriented tissue. Tissue orientation had little effect on the movement of the other compounds. Mobility of the compounds studied, in general, appears to be a function of the amount of uncomplexed parent chemical. Retention is likely the result of conjugation with products in the cells or of physical binding in the cells.

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