Quantitative Evaluation of the Trade-Off Growth Strategies of Maize Leaves under Different Drought Severities

The leaf is one of the most drought-sensitive plant organs. Investigating how leaf traits change and their trade-off growth during a drought would contribute to developing targeted drought-resistance measures. We investigated changes in five key maize leaf traits (leaf area, dry mass, effective number, water content, and specific weight) and their trade-off growth based on a drought simulation experiment. We also developed an indicator (0, 1) to quantitatively evaluate drought severity. The results showed a trade-off growth between different leaf traits of maize plants under drought conditions. Maize maintained relatively high leaf water content to maintain high leaf metabolic activity until drought severity was greater than 0. When drought severity was (0, 0.48), maize tended to adopt rapid growth strategy by maintaining regular leafing intensity and investing more energy into leaf area rather than specific leaf weight so that more energy could be absorbed. When the drought severity exceeded 0.48, maize conserved its resources for survival by maintaining relatively lower metabolic activity and thicker leaves to minimize water loss. The results provide an insight into the acclimation strategies of maize under drought, and contribute to targeted drought prevention and relief measures to reduce drought-induced risks to food security.

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Stem trait spectra underpin multiple functions of temperate gymnosperm and angiosperm tree species

10.21203/rs.3.rs-168427/v1 ◽

2021 ◽

Author(s):

Shanshan Yang ◽

Frank J. Sterck ◽

Ute Sass-Klaassen ◽

J. Hans C. Cornelissen ◽

Richard S.P. van Logtestijn ◽

...

Keyword(s):

Tree Species ◽

Leaf Traits ◽

Fast Growth ◽

Growth Strategy ◽

Trade Off ◽

Plant Strategy ◽

Leaf Habit ◽

Angiosperm Species ◽

Central Paradigm ◽

Diffuse Porous

Abstract A central paradigm in comparative ecology is that species sort out along a global economic strategy spectrum, ranging from slow to fast growth. Many studies evaluated plant strategy spectra for leaf traits, b u t few studies evaluated stem strategy spectra using a comprehensive set of anatomical, chemical and morphological traits, addressing key stem functions of different stem compartments (inner wood, outer wood and bark). This study evaluates how stem traits vary in the wood and bark of temperate tree species, and whether a slow-fast growth strategy spectrum exists and what traits make up this plant strategy spectrum. For 14 temperate gymnosperm and angiosperm species, 20 traits belonging to six key stem functions were measured for three stem compartments. Both across and within gymnosperms and angiosperms, a slow-fast stem strategy spectrum is found. Gymnosperms have slow traits and showed converging stem strategies because of their uniform tracheids. Angiosperms have fast traits and showed diverging stem strategies because of a wider array of tissues (vessels, parenchyma and fibers) and vessel size and arrangements (ring-porous versus diffuse porous). Gymnosperms showed a main trade-off between hydraulic efficiency and safety, and angiosperms showed a main trade-off between ‘slow’ diffuse porous species and ‘fast’ ring porous species. The slow traits of gymnosperms allow for a high hydraulic safety, an evergreen leaf habit and steady but slow growth makes them successful in unproductive habitats whereas the fast traits of angiosperms allow for high conductivity, a deciduous leaf habit and fast growth which makes them successful in productive habitats.

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Relationship between specific leaf area, leaf thickness, leaf water content and SPAD-502 readings in six Amazonian tree species

Photosynthetica ◽

10.1007/s11099-009-0031-6 ◽

2009 ◽

Vol 47 (2) ◽

pp. 184-190 ◽

Cited By ~ 88

Author(s):

R.A. Marenco ◽

S.A. Antezana-Vera ◽

H.C.S. Nascimento

Keyword(s):

Water Content ◽

Leaf Area ◽

Specific Leaf Area ◽

Tree Species ◽

Leaf Water ◽

Leaf Thickness ◽

Leaf Water Content

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Growth strategies of clonal palms (Arecaceae) in a neotropical rainforest, Yasuni, Ecuador

Australian Journal of Botany ◽

10.1071/bt98048 ◽

2000 ◽

Vol 48 (2) ◽

pp. 167 ◽

Cited By ~ 20

Author(s):

Jens-Christian Svenning

Keyword(s):

Light Availability ◽

Common Species ◽

Clonal Reproduction ◽

Growth Strategy ◽

Stem Diameter ◽

Growth Strategies ◽

Strong Constraint ◽

Trade Off ◽

Stem Bending ◽

Neotropical Rainforest

Growth strategies of clonal palms were studied in old-growth tropical rainforest in Yasuní, Amazonian Ecuador. Genet structure, clonal and sexual fecundity, and light availability were investigated for 188 genets totalling 1256 ramets and 10 species. Negative relationships between risk of stem bending and stem diameter and between stem diameter and number of large ramets per genet were found. Recruitment of thick-stemmed species occurred in better-lit microsites than where the smaller species occurred. The three most common species were studied in more detail. Clonal and sexual fecundity were only related to light availability in one species each. No general trade-off between sexual and clonal reproduction was found. Sexual fecundity was related to size in all three species, while clonal fecundity was so only in one species. Overall, the results suggest that light availability poses a strong constraint on the evolution of growth strategies in clonal understorey palms, while the resource cost of sexual reproduction is not high enough to result in a general trade-off between sexual and clonal reproduction. It is also concluded that in understorey palms clonal growth is more a growth strategy than a dispersion-propagation strategy.

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Leaf Area and Absolute Leaf Water Content

Annals of Botany ◽

10.1093/oxfordjournals.aob.a084366 ◽

1970 ◽

Vol 34 (2) ◽

pp. 259-266 ◽

Cited By ~ 15

Author(s):

A. P. HUGHES ◽

K. E. COCKSHULL ◽

O. V. S. HEATH

Keyword(s):

Water Content ◽

Leaf Area ◽

Leaf Water ◽

Leaf Water Content

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Growth strategies as determinants of CO2 sequestration and response to nitrogen fertilisation in C4 grasses in South American natural grasslands

Crop and Pasture Science ◽

10.1071/cp19301 ◽

2020 ◽

Vol 71 (8) ◽

pp. 776

Author(s):

Anderson Cesar Ramos Marques ◽

Leandro Bittencourt de Oliveira ◽

Raíssa Schwalbert ◽

Bianca Knebel Del Frari ◽

Gustavo Brunetto ◽

...

Keyword(s):

Leaf Area ◽

Resource Conservation ◽

Co2 Assimilation ◽

Growth Strategy ◽

Grass Species ◽

South American ◽

N Addition ◽

Growth Strategies ◽

Resource Capture ◽

Natural Grasslands

Grass species grown in South American natural grasslands present different growth strategies related to variations in specific leaf area (SLA), leaf dry matter content (LDMC) and possible nitrogen (N) allocation. Nitrogen fertilisation can have effects on physiological processes such as CO2 assimilation; however, these responses can change depending on the growth strategy adopted by each species. The aim of the present study is to determine the effects of N fertilisation on SLA, LDMC and CO2 assimilation in eight C4 grass species: Axonopus affinis, Paspalum pumilum, P. notatum, P. urvillei, P. plicatulum, Andropogon lateralis, Saccharum angustifolium and Aristida laevis. These species were cultivated in pots filled with soil subjected to two conditions of N availability: nil (control) and 200 mg N kg–1 soil. The SLA of Axonopus affinis was 5.4 times higher than that of Aristida laevis. Axonopus affinis and P. pumilum recorded the lowest LDMC, their leaves showed 53% lower LDMC than observed for Aristida laevis, on average. Resource-capture species showed variation in leaf area with N addition to values 20% higher than the control, whereas species characterised by a resource-conservation growth strategy recorded variation in leaf area with N addition to values only 8% higher than the control. With N addition, the CO2 assimilation of resource-capture species represented variation (increase) nine times that of resource-conservation species compared with their respective controls. Resource-capture species have greater CO2 capture potential than resource-conservation species, mainly a result of N addition.

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Increase in Absolute Leaf Water Content Tends to Keep Pace with That of Leaf Dry Mass—Evidence from Bamboo Plants

Symmetry ◽

10.3390/sym12081345 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1345

Author(s):

Weiwei Huang ◽

Gadi V. P. Reddy ◽

Yueyi Li ◽

Jørgen Bo Larsen ◽

Peijian Shi

Keyword(s):

Water Content ◽

Leaf Area ◽

Dry Mass ◽

Leaf Water ◽

Fresh Mass ◽

Leaf Water Content ◽

Scaling Exponent ◽

Venation Pattern ◽

Leaf Dry Mass ◽

Scaling Relationship

Leaves, as the most important photosynthetic organ of plants, are intimately associated with plant function and adaptation to environmental changes. The scaling relationship of the leaf dry mass (or the fresh mass) vs. leaf surface area has been referred to as “diminishing returns”, suggesting that the leaf area fails to increase in proportion to leaf dry mass (or fresh mass). However, previous studies used materials across different families, and there is lack of studies testing whether leaf fresh mass is proportional to the leaf dry mass for the species in the same family, and examining the influence of the scaling of leaf dry mass vs. fresh mass on two kinds of diminishing returns based on leaf dry mass and fresh mass. Bamboo plants (Poaceae: Bambusoideae) are good materials for doing such a study, which have astonishingly similar leaf shapes across species. Bamboo leaves have a typical parallel venation pattern. In general, a parallel venation pattern tends to produce a more stable symmetrical leaf shape than the pinnate and palmate venation patterns. The symmetrical parallel veins enable leaves to more regularly hold water, which is more likely to result in a proportional relationship between the leaf dry mass and absolute water content, which consequently determines whether the scaling exponent of the leaf dry mass vs. area is significantly different from (or the same as) that of the leaf fresh mass vs. area. In the present study, we used the data of 101 bamboo species, cultivars, forms and varieties (referred to as 101 (bamboo) taxa below for convenience) to analyze the scaling relationships between the leaf dry mass and area, and between leaf fresh mass and area. We found that the confidence intervals of the scaling exponents of the leaf fresh mass vs. dry mass of 68 out of the 101 taxa included unity, which indicates that for most bamboo species (67.3%), the increase in leaf water mass keeps pace with that of leaf dry mass. There was a significant scaling relationship between either leaf dry mass or fresh mass, and the leaf surface area for each studied species. We found that there was no significant difference between the scaling exponent of the leaf dry mass vs. leaf area and that of the leaf fresh mass vs. leaf area when the leaf dry mass was proportional to the leaf fresh mass. The goodness of fit to the linearized scaling relationship of the leaf fresh mass vs. area was better than that of the leaf dry mass vs. area for each of the 101 bamboo taxa. In addition, there were significant differences in the normalized constants of the leaf dry mass vs. fresh mass among the taxa (i.e., the differences in leaf water content), which implies the difference in the adaptabilities to different environments across the taxa.

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MITIGATION OF EXCESSIVE SOLAR RADIATION AND WATER STRESS ON ‘KEITT’ MANGO Mangifera indica TREES THROUGH SHADING

Acta Scientiarum Polonorum Hortorum Cultus ◽

10.24326/asphc.2021.4.7 ◽

2021 ◽

Vol 20 (4) ◽

pp. 77-88

Author(s):

Ayman E.A. Shaban ◽

Ahmed A. Rashedy ◽

Mohammed I.M. El-Banna

Keyword(s):

Powdery Mildew ◽

Solar Radiation ◽

Water Content ◽

Leaf Area ◽

Chlorophyll Content ◽

Fruit Set ◽

Proline Content ◽

Leaf Water Content ◽

Irrigation Level ◽

Relative Water

Excessive solar radiation “global warming” and water scarcity are consider the main environmental constraints for plant growth and production under arid and semi-arid regions. The current research was aimed to study the effect of irrigation levels (100%, 85%, 70% of irrigation requirements), and shading levels (60%, 40%, 0%) on the growth and productivity of ‘Keitt’ mango trees. This experiment was conducted during two growing seasons (2016/2017 and 2017/2018) at El Behera Governorate, Egypt. Decreasing irrigation level (IR) decreased leaf area, malformed panicle, powdery mildew infection, final fruit set, fruit numbers, yield but it increased chlorophyll content, proline content, leaf water content. While, increasing shading levels (SH) increased leaves number, leaf area, fruit set, powdery mildew infection, malformed panicle but it decreased fruit sunburn damage, proline content, chlorophyll content and relative water content. Moreover, accumulative effects of 85% IR + 40% SH significantly increased leaf area, fruit set, fruit number, yield, chlorophyll content, WUE, proline content, relative water content, leaf water content while decreasing powdery mildew and sunburn damage. Results suggest that shading at 40% increased the yield up to 20% and decreased sunburn damage up to 0% under irrigation level of 70%. Shading may be a new technique to alleviate the adverse effects of water stress beside their role in avoiding excessive solar radiation on ‘Keitt’ mango trees.

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