Diversity in nonlinear responses to soil moisture shapes evolutionary constraints in Brachypodium

Abstract Water availability is perhaps the greatest environmental determinant of plant yield and fitness. However, our understanding of plant-water relations is limited because—like many studies of organism-environment interaction—it is primarily informed by experiments considering performance at two discrete levels—wet and dry—rather than as a continuously varying environmental gradient. Here, we used experimental and statistical methods based on function-valued traits to explore genetic variation in responses to a continuous soil moisture gradient in physiological and morphological traits among 10 genotypes across two species of the model grass genus Brachypodium. We find that most traits exhibit significant genetic variation and nonlinear responses to soil moisture variability. We also observe differences in the shape of these nonlinear responses between traits and genotypes. Emergent phenomena arise from this variation including changes in trait correlations and evolutionary constraints as a function of soil moisture. Our results point to the importance of considering diversity in nonlinear organism-environment relationships to understand plastic and evolutionary responses to changing climates.

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Trait plasticity and covariance along a continuous soil moisture gradient

10.1101/2020.02.17.952853 ◽

2020 ◽

Author(s):

J. Grey Monroe ◽

Haoran Cai ◽

David L. Des Marais

Keyword(s):

Soil Moisture ◽

Water Relations ◽

Moisture Gradient ◽

Plant Water Relations ◽

Plant Water ◽

Soil Moisture Gradient ◽

Non Linear ◽

Model Grass ◽

Soil Moisture Variability ◽

Moisture Variability

Water availality is perhaps the greatest environmental determinant of plant yield and fitness. Yet our understanding of plant-water relations is limited because it is primarily informed by experiments considering soil moisture variability at two discrete levels - wet and dry - rather than as a continually varying environmental gradient. Here we used experimental and statistical methods based on function-valued traits to explore responses to continuously varying soil moisture gradient in physiological and morphological traits in two species and five genotypes each of the model grass Brachypodium. We find that most traits exhibit non-linear responses to soil moisture variability. We also observe differences in the shape of these non-linear responses between traits, species, and genotypes. Emergent phenomena arise from this variation including changes in trait correlations and evolutionary constraints as a function of soil moisture. These results point to the importance of considering non-linearity in plant-water relations to understand plastic and evolutionary responses to changing climates.

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Family variation in photosynthesis of 22-year-old black spruce: a test of two models of physiological response to water stress

Canadian Journal of Forest Research ◽

10.1139/x26-217 ◽

1996 ◽

Vol 26 (11) ◽

pp. 1922-1933 ◽

Cited By ~ 32

Author(s):

John E. Major ◽

Kurt H. Johnsen

Keyword(s):

Genetic Variation ◽

Soil Moisture ◽

Water Potential ◽

Black Spruce ◽

Alternative Hypothesis ◽

Genetic Differences ◽

Environment Interaction ◽

Physiological Measurement ◽

Genotype Environment Interaction ◽

Moisture Conditions

Gas exchange and water potential were measured in 22-year-old black spruce (Piceamariana (Mill.) BSP) trees from four full-sib families on two sites (one drier and one wetter) at the Petawawa National Forestry Institute, Ontario. Based on an observed genotype × environment interaction and earlier work with seedlings, a hypothesis was formed that at high soil moisture availability, no genetic differences in net photosynthesis (Pn) would exist and as soil moisture decreases, genetic differences in Pn would increase. From results of initial research with mature trees we formed an alternative hypothesis that genetic differences in Pn are constantly maintained under an array of soil moisture conditions. The two models were rigorously tested over a range of soil moisture conditions using two physiological measurement crews who switched sites throughout the day. Second-year foliage Pn of mature black spruce was more affected by nonstomatal limitations than by stomatal limitations. Progeny of one female had 12.5% and 7.4% higher Pn than progeny of another female on the dry and wet site, respectively. Genetic variation in Pn was consistent over a range of soil water potential. Thus, the first hypothesis was rejected in favor of the alternative hypothesis. Genetic variation in Pn appeared to be due to differential response to vapor pressure deficit. Suggestions as to how to reconcile the observed genotype × environment interaction in growth with the genetic differences in Pn are discussed.

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Quantitative genetic variation and natural selection in Cleome serrulata growing along a mild soil moisture gradient

Canadian Journal of Botany ◽

10.1139/b88-255 ◽

1988 ◽

Vol 66 (9) ◽

pp. 1870-1876 ◽

Cited By ~ 15

Author(s):

Michael A. Farris

Keyword(s):

Genetic Variation ◽

Soil Moisture ◽

Growth Rates ◽

Moisture Gradient ◽

Height Growth ◽

Directional Selection ◽

Leaf Number ◽

Selection Pressures ◽

Quantitative Genetic ◽

Soil Moisture Gradient

The purpose of this study was to determine the potential for evolutionary change for several growth characters in a natural population of the annual plant Cleome serrulata Pursh by measuring directional selection pressures and quantitative genetic variation. The population grew along a mild soil moisture gradient, which allowed changes in selection pressures along the environmental gradient to be assessed. Directional selection pressures were calculated for initial height, height growth rate, initial leaf number, and leaf production rate for the wet and dry halves of the population separately. Narrow-sense heritabilities and genetic correlation estimates for these four variables, along with seed mass and emergence time, were estimated in the greenhouse from the offspring of controlled crosses. Selection pressures varied among phenotypic characters for different fitness components and subpopulations. Viability selection on the four characters was similar in the wet and dry subpopulations, with faster height growth rates being favored. Fecundity selection on all four characters was quite different in the wet and dry subpopulations. Overall, there was significant net positive selection on height characters in the dry subpopulation and on leaf number characters in the wet subpopulation. Height characters had lower heritabilities than leaf number characters but showed stronger maternal effects. Initial size measures showed negative genetic correlations with growth rates. The results suggested that these morphological characters had a greater impact on fitness in wetter areas, while physiological characters were more important in the drier areas.

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Screening Marker Varieties with Drought Resistance in Cultivated Rice (Oryza sativa L.) Using Identification Method with Soil Moisture Gradient

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1006.2008.02026 ◽

2009 ◽

Vol 34 (11) ◽

pp. 2026-2032 ◽

Cited By ~ 1

Author(s):

An-Ning ZHANG

Keyword(s):

Oryza Sativa ◽

Soil Moisture ◽

Drought Resistance ◽

Moisture Gradient ◽

Cultivated Rice ◽

Identification Method ◽

Soil Moisture Gradient ◽

Screening Marker

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A geospatial method for estimating soil moisture variability in prehistoric agricultural landscapes

PLoS ONE ◽

10.1371/journal.pone.0220457 ◽

2019 ◽

Vol 14 (8) ◽

pp. e0220457 ◽

Cited By ~ 2

Author(s):

Andrew Gillreath-Brown ◽

Lisa Nagaoka ◽

Steve Wolverton

Keyword(s):

Soil Moisture ◽

Agricultural Landscapes ◽

Soil Moisture Variability ◽

Moisture Variability

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Genotype by environment interaction for yearling weight in Nellore cattle applying reaction norms models

Animal Production Science ◽

10.1071/an17048 ◽

2018 ◽

Vol 58 (11) ◽

pp. 1996

Author(s):

S. Ribeiro ◽

J. P. Eler ◽

V. B. Pedrosa ◽

G. J. M. Rosa ◽

J. B. S. Ferraz ◽

...

Keyword(s):

Genetic Correlation ◽

Environmental Gradient ◽

Genotype By Environment Interaction ◽

Reaction Norms ◽

Breeding Value ◽

Environment Interaction ◽

Genotype By Environment ◽

Genotype Environment Interaction ◽

Nellore Cattle ◽

Gradient Variation

In the present study, a possible existence of genotype × environment interaction was verified for yearling weight in Nellore cattle, utilising a reaction norms model. Therefore, possible changes in the breeding value were evaluated for 46 032 animals, from three distinct herds, according to the environmental gradient variation of the different contemporary groups. Under a Bayesian approach, analyses were carried out utilising INTERGEN software resulting in solutions of contemporary groups dispersed in the environmental gradient from –90 to +100 kg. The estimates of heritability coefficients ranged from 0.19 to 0.63 through the environmental gradient and the genetic correlation between intercept and slope of the reaction norms was 0.76. The genetic correlation considering all animals of the herds in the environmental gradient ranged from 0.83 to 1.0, and the correlation between breeding values of bulls in different environments ranged from 0.79 to 1.0. The results showed no effect of genotype × environment interaction on yearling weight in the herds of this study. However, it is important to verify a possible influence of the genotype × environment in the genetic evaluation of beef cattle, as different environments might cause interference in gene expression and consequently difference in phenotypic response.

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EFFECT OF DEFICIT IRRIGATION ON YIELD, RELATIVE LEAF WATER CONTENT, LEAF PROLINE ACCUMULATION AND CHLOROPHYLL STABILITY INDEX OF COTTON–MAIZE CROPPING SEQUENCE

Experimental Agriculture ◽

10.1017/s0014479713000598 ◽

2013 ◽

Vol 50 (3) ◽

pp. 407-425 ◽

Cited By ~ 5

Author(s):

T. SAMPATHKUMAR ◽

B. J. PANDIAN ◽

P. JEYAKUMAR ◽

P. MANICKASUNDARAM

Keyword(s):

Soil Moisture ◽

Water Stress ◽

Water Content ◽

Deficit Irrigation ◽

Stability Index ◽

Moisture Gradient ◽

Proline Content ◽

Leaf Water Content ◽

Chlorophyll Stability Index ◽

Soil Moisture Gradient

SUMMARYWater stress induces some physiological changes in plants and has cumulative effects on crop growth and yield. Field experiments were conducted to study the effect of deficit irrigation (DI) on yield and some physiological parameters in cotton and maize in a sequential cropping system. Creation of soil moisture gradient is indispensable to explore the beneficial effects of partial root zone drying (PRD) irrigation and it could be possible only through alternate deficit irrigation (ADI) practice in paired row system of drip layout that is commonly practiced in India. In the present study, PRD and DI concepts (creation of soil moisture gradient) were implemented through ADI at two levels of irrigation using drip system. Maize was sown after cotton under no till condition without disturbing the raised bed and drip layout. Relative leaf water content (RLWC) and chlorophyll stability index (CSI) of cotton and maize were reduced under water stress. A higher level of leaf proline content was observed under severe water-stressed treatments in cotton and maize. RLWC and CSI were highest and leaf proline content was lowest in mild water deficit (ADI at 100% crop evapotranspiration once in three days) irrigation in cotton and maize. The same treatments registered higher values for crop yields, net income and benefit cost ratio for both the crops.

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Bacterial and fungal community responses to reciprocal soil transfer along a temperature and soil moisture gradient in a glacier forefield

Soil Biology and Biochemistry ◽

10.1016/j.soilbio.2013.02.017 ◽

2013 ◽

Vol 61 ◽

pp. 121-132 ◽

Cited By ~ 52

Author(s):

Anita Zumsteg ◽

Erland Bååth ◽

Beat Stierli ◽

Josef Zeyer ◽

Beat Frey

Keyword(s):

Soil Moisture ◽

Fungal Community ◽

Moisture Gradient ◽

Community Responses ◽

Glacier Forefield ◽

Soil Moisture Gradient ◽

Soil Transfer

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Vegetation of the Witbank Nature Reserve and its importance for conservation of threatened Rocky Highveld Grassland

Koedoe ◽

10.4102/koedoe.v40i2.275 ◽

1997 ◽

Vol 40 (2) ◽

Cited By ~ 10

Author(s):

C.M. Smit ◽

G.J. Bredenkamp ◽

N. Van Rooyen ◽

A.E. Van Wyk ◽

J.M. Combrinck

Keyword(s):

Soil Moisture ◽

Plant Communities ◽

Nature Reserve ◽

Soil Depth ◽

Floristic Composition ◽

Diversity Indices ◽

Moisture Gradient ◽

Negative Effects ◽

Soil Moisture Gradient ◽

Great Escarpment

A vegetation survey of the Witbank Nature Reserve, comprising 847 hectares, was conducted. Phytosociological data were used to identify plant communities, as well as to determine alpha and beta diversities. Eleven plant communities were recognised, two of these are subdivided into sub- communities, resulting in 14 vegetation units. These communities represent four main vegetation types, namely grassland, woodland, wetland and disturbed vegetation. Grassland communities have the highest plant diversity and wetland vegetation the lowest. Floristic composition indicates that the vegetation of the Rocky Highveld Grassland has affinities to the grassland and savanna biomes and also to the Afromontane vegetation of the Great Escarpment. An ordination scatter diagram shows the distribution of the 14 plant communities or sub-communities along a soil moisture gradient, as well as along a soil depth/surface rock gradient. The sequence of communities along the soil moisture gradient is used for calculating beta-diversity indices. It is concluded that the relatively small size of the Witbank Nature Reserve is unlikely to have significant negative effects on the phytodiversity of the various plant communities. This nature reserve is therefore of considerable importance in conserving a representative sample of the Rocky Highveld Grassland.

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