Turgor Maintenance in Rosa rugosa Grown at Three Levels of Nitrogen and Subjected to Drought

Abstract The influence of N fertilization on turgor maintenance was determined in leaves from well-watered and droughted Rosa rugosa L. Plants were fertilized for 60 days with a complete fertilizer with N at levels of 0, 200 or 500 ppm and then subjected to several drought cycles for 22 days. Plants receivmg no N were stunted and chlorotic, but had the greatest full saturation turgor pressure and symplastic osmolality, and the lowest full saturation osmotic potential, after drought. These plants also maintained higher turgor across a range of leaf water potentials and relative water contents. Leaf water content at full turgor and relative water content at the turgor loss point were also lower in plants without N. N treatments of 200 and 500 ppm had similar water relations under both well-watered and drought conditions.

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LEAF WATER CONTENT AND POTENTIAL IN CORN, SORGHUM, SOYBEAN, AND SUNFLOWER

Canadian Journal of Plant Science ◽

10.4141/cjps74-028 ◽

1974 ◽

Vol 54 (1) ◽

pp. 185-195 ◽

Cited By ~ 13

Author(s):

H. H. NEUMANN ◽

G. W. THURTELL ◽

K. R. STEVENSON ◽

C. L. BEADLE

Keyword(s):

Water Potential ◽

Water Content ◽

Leaf Water Potential ◽

Leaf Water ◽

Leaf Water Content ◽

Relative Water ◽

Helianthus Annus ◽

Glycine Max L ◽

Water Contents

The Peltier-cooled thermocouple dewpoint hygrometer technique of in situ measurement of leaf water potential was further developed. The observed response of the instrument agreed so well with theoretical analysis that calibration based on theory was within 1% of that obtained using salt solutions of known water potential. Simultaneous measurements with the hygrometer and a beta gauge were made to derive the leaf water content–potential relationships for several crop plants. Results showed relative water contents dropping only to near 0.95 for mature corn (Zea mays L.); sorghum (Sorghum vulgare Pers.); and sunflower (Helianthus annus L.) leaves, and to 0.90 for not quite mature soybean (Glycine max (L.) Merr.) leaves as potentials declined from near −1 bar to the plant wilting point (−8 to −14 bars). Further decline of leaf water potential resulted in relatively much greater loss of leaf water.

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An Equilibrium Model of Leaf Water Potentials Which Separates Intra- and Extracellular Potentials

Functional Plant Biology ◽

10.1071/pp9750253 ◽

1975 ◽

Vol 2 (3) ◽

pp. 253 ◽

Cited By ~ 8

Author(s):

B Acock

Keyword(s):

Water Content ◽

Turgor Pressure ◽

Bound Water ◽

Leaf Tissue ◽

High Water ◽

Leaf Water ◽

High Water Content ◽

Pressure Potential ◽

Matrix Bound ◽

Water Contents

A model is proposed which makes it possible to estimate the intracellular turgor pressure potential, intracellular osmotic plus matric potential, and intra- and extracellular soIution fractions of water in leaf tissue at any water content. The model requires only the data normally collected with a thermocouple psychrometer: total water potential of live and dead (cells ruptured) tissue at various known water contents. The major assumptions are that (1) the total potential of water in the solution fraction in any part of the tissue multiplied by the volume of water is constant; (2) extracellular water experiences no pressure potential; (3) matrix-bound water is held only by matric forces and contains no solute; (4) the solution fraction of the intracellular water is constant at high water content; and (5) matrix-bound water content is constant over the range of leaf water contents normally examined. The models developed to deal with pressure bomb data are examined critically and doubts are cast on the validity of some of their assumptions.

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Leaf water content estimation using top-of-canopy airborne hyperspectral data

International Journal of Applied Earth Observation and Geoinformation ◽

10.1016/j.jag.2021.102393 ◽

2021 ◽

Vol 102 ◽

pp. 102393

Author(s):

Rahul Raj ◽

Jeffrey P. Walker ◽

Vishal Vinod ◽

Rohit Pingale ◽

Balaji Naik ◽

...

Keyword(s):

Water Content ◽

Hyperspectral Data ◽

Leaf Water ◽

Leaf Water Content

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Capability of leaf water content and its threshold values in reflection of soil–plant water status in maize during prolonged drought

Ecological Indicators ◽

10.1016/j.ecolind.2021.107395 ◽

2021 ◽

Vol 124 ◽

pp. 107395

Author(s):

Huailin Zhou ◽

Guangsheng Zhou ◽

Qijin He ◽

Li Zhou ◽

Yuhe Ji ◽

...

Keyword(s):

Water Content ◽

Water Status ◽

Leaf Water ◽

Plant Water Status ◽

Leaf Water Content ◽

Plant Water ◽

Threshold Values ◽

Prolonged Drought

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Simulating Heat Stress of Coal Gangue Spontaneous Combustion on Vegetation Using Alfalfa Leaf Water Content Spectral Features as Indicators

Remote Sensing ◽

10.3390/rs13132634 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2634

Author(s):

Qiyuan Wang ◽

Yanling Zhao ◽

Feifei Yang ◽

Tao Liu ◽

Wu Xiao ◽

...

Keyword(s):

Heat Stress ◽

Water Content ◽

Spontaneous Combustion ◽

Leaf Water ◽

Coal Gangue ◽

Leaf Water Content ◽

Spectral Features ◽

Lasso Regression ◽

Stress Assessment ◽

First Derivative

Vegetation heat-stress assessment in the reclamation areas of coal gangue dumps is of great significance in controlling spontaneous combustion; through a temperature gradient experiment, we collected leaf spectra and water content data on alfalfa. We then obtained the optimal spectral features of appropriate leaf water content indicators through time series analysis, correlation analysis, and Lasso regression analysis. A spectral feature-based long short-term memory (SF-LSTM) model is proposed to estimate alfalfa’s heat stress level; the live fuel moisture content (LFMC) varies significantly with time and has high regularity. Correlation analysis of the raw spectrum, first-derivative spectrum, spectral reflectance indices, and leaf water content data shows that LFMC and spectral data were the most strongly correlated. Combined with Lasso regression analysis, the optimal spectral features were the first-derivative spectral value at 1661 nm (abbreviated as FDS (1661)), RVI (1525,1771), DVI (1412,740), and NDVI (1447,1803). When the classification strategies were divided into three categories and the time sequence length of the spectral features was set to five consecutive monitoring dates, the SF-LSTM model had the highest accuracy in estimating the heat stress level in alfalfa; the results provide an important theoretical basis and technical support for vegetation heat-stress assessment in coal gangue dump reclamation areas.

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Spectral assessments of wheat plants grown in pots and containers under saline conditions

Functional Plant Biology ◽

10.1071/fp12208 ◽

2013 ◽

Vol 40 (4) ◽

pp. 409 ◽

Cited By ~ 16

Author(s):

Harald Hackl ◽

Bodo Mistele ◽

Yuncai Hu ◽

Urs Schmidhalter

Keyword(s):

Water Potential ◽

Water Content ◽

Aboveground Biomass ◽

Leaf Water ◽

Leaf Water Content ◽

Spectral Indices ◽

Fresh Weight ◽

Normalised Difference Vegetation Index ◽

Spectral Sensing ◽

Reflectance Ratio

Spectral measurements allow fast nondestructive assessment of plant traits under controlled greenhouse and close-to-field conditions. Field crop stands differ from pot-grown plants, which may affect the ability to assess stress-related traits by nondestructive high-throughput measurements. This study analysed the potential to detect salt stress-related traits of spring wheat (Triticum aestivum L.) cultivars grown in pots or in a close-to-field container platform. In two experiments, selected spectral indices assessed by active and passive spectral sensing were related to the fresh weight of the aboveground biomass, the water content of the aboveground biomass, the leaf water potential and the relative leaf water content of two cultivars with different salt tolerance. The traits were better ascertained by spectral sensing of container-grown plants compared with pot-grown plants. This may be due to a decreased match between the sensors’ footprint and the plant area of the pot-grown plants, which was further characterised by enhanced senescence of lower leaves. The reflectance ratio R760 : R670, the normalised difference vegetation index and the reflectance ratio R780 : R550 spectral indices were the best indices and were significantly related to the fresh weight, the water content of the aboveground biomass and the water potential of the youngest fully developed leaf. Passive sensors delivered similar relationships to active sensors. Across all treatments, both cultivars were successfully differentiated using either destructively or nondestructively assessed parameters. Although spectral sensors provide fast and qualitatively good assessments of the traits of salt-stressed plants, further research is required to describe the potential and limitations of spectral sensing.

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Effect of dust deposition on spectrum-based estimation of leaf water content in urban plant

Ecological Indicators ◽

10.1016/j.ecolind.2019.04.074 ◽

2019 ◽

Vol 104 ◽

pp. 41-47 ◽

Cited By ~ 4

Author(s):

Wenpeng Lin ◽

Yuan Li ◽

Shiqiang Du ◽

Yuanfan Zheng ◽

Jun Gao ◽

...

Keyword(s):

Water Content ◽

Leaf Water ◽

Leaf Water Content ◽

Dust Deposition

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Water stress affects the productivity, growth components, competitiveness and water relations of phalaris and white clover growing in a mixed pasture

Australian Journal of Agricultural Research ◽

10.1071/ar9920659 ◽

1992 ◽

Vol 43 (3) ◽

pp. 659 ◽

Cited By ~ 12

Author(s):

L Guobin ◽

DR Kemp ◽

GB Liu

Keyword(s):

Water Stress ◽

Soil Water ◽

White Clover ◽

Leaf Growth ◽

Leaf Water ◽

Water Potentials ◽

Relative Water ◽

Dry Conditions ◽

Leaf Appearance ◽

Water Contents

The effect of water stress during summer and recovery after rain on herbage accumulation, leaf growth components, stomatal conductance and leaf water relations of white clover (Trifolium repens cv. Haifa) and phalaris (Phalaris aquatica cv. Australian Commercial) was studied in an established mixed pasture under dryland (dry) or irrigated (wet) conditions. Soil water deficits under dry conditions reached 150 mm and soil water potentials in the top 20 cm declined to nearly -2 MPa after 50 days of dry weather. Water stress severely restricted growth of both species but then after rain fell, white clover growth rates exceeded those of phalaris. Under irrigation, white clover produced twice the herbage mass of phalaris but under dry conditions herbage production was similar from both species. Leaf appearance rates per tiller or stolon were slightly higher for white clover than phalaris but were reduced by 20% under water stress in both species. Leaf or petiole extension rates were more sensitive to water stress than leaf appearance rates and declined by 75% in phalaris and 90% in white clover. The ratio of leaf or petiole extension rates on dry/wet treatments was similar for both species in relation to leaf relative water contents, but in relation to leaf water potentials phalaris maintained higher leaf growth rates. Phalaris maintained a higher leaf relative water content in relation to leaf water potentials than did white clover and also maintained higher leaf water potentials in relation to the soil water potential in the top 20 cm. Stomata1 conductances for both species declined by 80-90% with increasing water stress, and both species showed similar stomatal responses to bulk leaf water potentials and leaf relative water contents. It is suggested that the poorer performance of white clover under water stress may be due principally to a shallower root system than phalaris and not due to any underlying major physiological differences. The white clover cultivar used in this study came from the mediterranean region and showed some different responses to water stress than previously published evidence on white clover. This suggests genetic variation in responses to water stress may exist within white clover. To maintain white clover in a pasture under dry conditions it is suggested that grazing practices aim to retain a high proportion of growing points.

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Spatial variation and mechanisms of leaf water content in grassland plants at the biome scale: evidence from three comparative transects

Scientific Reports ◽

10.1038/s41598-021-88678-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ruomeng Wang ◽

Nianpeng He ◽

Shenggong Li ◽

Li Xu ◽

Mingxu Li

Keyword(s):

Spatial Variation ◽

Water Content ◽

Large Scale ◽

Life Forms ◽

Important Variable ◽

Leaf Water ◽

Leaf Water Content ◽

Desert Grassland ◽

Large Spatial Scale ◽

Grassland Plants

AbstractLeaf water content (LWC) has important physiological and ecological significance for plant growth. However, it is still unclear how LWC varies over large spatial scale and with plant adaptation strategies. Here, we measured the LWC of 1365 grassland plants, along three comparative precipitation transects from meadow to desert on the Mongolia Plateau (MP), Loess Plateau, and Tibetan Plateau, respectively, to explore its spatial variation and the underlying mechanisms that determine this variation. The LWC data were normally distributed with an average value of 0.66 g g−1. LWC was not significantly different among the three plateaus, but it differed significantly among different plant life forms. Spatially, LWC in the three plateaus all decreased and then increased from meadow to desert grassland along a precipitation gradient. Unexpectedly, climate and genetic evolution only explained a small proportion of the spatial variation of LWC in all plateaus, and LWC was only weakly correlated with precipitation in the water-limited MP. Overall, the lasso variation in LWC with precipitation in all plateaus represented an underlying trade-off between structural investment and water income in plants, for better survival in various environments. In brief, plants should invest less to thrive in a humid environment (meadow), increase more investment to keep a relatively stable LWC in a drying environment, and have high investment to hold higher LWC in a dry environment (desert). Combined, these results indicate that LWC should be an important variable in future studies of large-scale trait variations.

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