EFFECTS OF DIFFERENT WATER STRESS LEVELS ON BIOMASS YIELD AND AGRONOMIC TRAITS OF SWITCHGRASS (Panicum virgatum L.) CULTIVARS UNDER ARID AND SEMI-ARID CONDITIONS

The objective of this study was to investigate the influence of water stress conditioning on the photosynthesis response of switchgrass (Panicum virgatum L.) and tall fescue (Festuca arundinacea Schreb.) to moisture deficiency. Tillers of the two species were grown in the same, controlled, environment and were subjected to three conditioning water stress cycles, or were kept well watered. After drought conditioning all plants were subjected to moisture deficiency while photosynthesis and leaf water potential were monitored. Measurements were taken between –0.8 and –4.0 MPa and the rate of water stress was 0.49 MPa/day. The conditioning of switchgrass produced a 26% reduction in the photosynthesis rate during drought, while that of tall fescue produced a 57% reduction in photosynthesis. Both species maintained elongation and photosynthesis down to lower leaf water potentials after drought conditioning than before conditioning. The conditioning water stress cycles decreased the leaf conductance, mesophyll resistance and transpiration of tall fescue plants after rewatering. The leaf water potential of conditioned switchgrass plants was lower upon rewatering after three conditioning water stress cycles than the leaf water potential of non-conditioned plants, while the leaf conductance, mesophyll resistance and transpiration of conditioned and non-conditioned tillers were equal. These data indicate an improvement in the drought tolerance of tall fescue and switchgrass plants, emphasize the importance of knowing the previous water stress history of the plants in moisture deficiency experiments, and help to choose proper irrigation management for switchgrass and tall fescue.

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The Water Relations of Barley Grown Continually or After Fallow Under Semi-Arid Conditions

Experimental Agriculture ◽

10.1017/s0014479700024674 ◽

1994 ◽

Vol 30 (4) ◽

pp. 431-439 ◽

Cited By ~ 6

Author(s):

P. I. Orphanos ◽

C. Metochis

Keyword(s):

Water Stress ◽

Grain Yield ◽

Water Relations ◽

Experimental Period ◽

Water Requirement ◽

Annual Rainfall ◽

Arid Conditions ◽

Semi Arid

SUMMARYGrain barley was grown either continually or in rotation with fallow in a 12-year experiment. Annual rainfall ranged from 120 to 297 mm. As the water requirement of the crop is 240 mm, growth in most seasons occurred under water stress. The amount of water conserved under fallow was only significant (75–100 mm) in three of the 12 years and only once did the water conserved increase barley yield in the following year. The total grain yield over the experimental period was twice as high in the barley–barley sequence as in the barley–fallow sequence.Cultiuo continuo de cebada o después de barbecho

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Cover crop evapotranspiration under semi-arid conditions using FAO dual crop coefficient method with water stress compensation

Agricultural Water Management ◽

10.1016/j.agwat.2007.06.010 ◽

2007 ◽

Vol 93 (3) ◽

pp. 85-98 ◽

Cited By ~ 65

Author(s):

G. Bodner ◽

W. Loiskandl ◽

H.-P. Kaul

Keyword(s):

Water Stress ◽

Cover Crop ◽

Crop Coefficient ◽

Crop Evapotranspiration ◽

Arid Conditions ◽

Stress Compensation ◽

Coefficient Method ◽

Semi Arid

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Intercomparison of four remote-sensing-based energy balance methods to retrieve surface evapotranspiration and water stress of irrigated fields in semi-arid climate

Hydrology and Earth System Sciences ◽

10.5194/hess-18-1165-2014 ◽

2014 ◽

Vol 18 (3) ◽

pp. 1165-1188 ◽

Cited By ~ 54

Author(s):

J. Chirouze ◽

G. Boulet ◽

L. Jarlan ◽

R. Fieuzal ◽

J. C. Rodriguez ◽

...

Keyword(s):

Water Stress ◽

Energy Balance ◽

Surface Energy ◽

Surface Energy Balance ◽

In Situ Data ◽

Stress Levels ◽

Single Pixel ◽

Semi Arid ◽

Svat Model

Abstract. Instantaneous evapotranspiration rates and surface water stress levels can be deduced from remotely sensed surface temperature data through the surface energy budget. Two families of methods can be defined: the contextual methods, where stress levels are scaled on a given image between hot/dry and cool/wet pixels for a particular vegetation cover, and single-pixel methods, which evaluate latent heat as the residual of the surface energy balance for one pixel independently from the others. Four models, two contextual (S-SEBI and a modified triangle method, named VIT) and two single-pixel (TSEB, SEBS) are applied over one growing season (December–May) for a 4 km × 4 km irrigated agricultural area in the semi-arid northern Mexico. Their performance, both at local and spatial standpoints, are compared relatively to energy balance data acquired at seven locations within the area, as well as an uncalibrated soil–vegetation–atmosphere transfer (SVAT) model forced with local in situ data including observed irrigation and rainfall amounts. Stress levels are not always well retrieved by most models, but S-SEBI as well as TSEB, although slightly biased, show good performance. The drop in model performance is observed for all models when vegetation is senescent, mostly due to a poor partitioning both between turbulent fluxes and between the soil/plant components of the latent heat flux and the available energy. As expected, contextual methods perform well when contrasted soil moisture and vegetation conditions are encountered in the same image (therefore, especially in spring and early summer) while they tend to exaggerate the spread in water status in more homogeneous conditions (especially in winter). Surface energy balance models run with available remotely sensed products prove to be nearly as accurate as the uncalibrated SVAT model forced with in situ data.

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Variance components and heritability of biomass yield in switchgrass (Panicum virgatum L.) grown in the Southern Great Plains

Field Crops Research ◽

10.1016/j.fcr.2014.07.016 ◽

2014 ◽

Vol 168 ◽

pp. 148-155 ◽

Cited By ~ 6

Author(s):

Qingzhen Jiang ◽

Stephen L. Webb ◽

Charles R. Yesudas ◽

Hem S. Bhandari ◽

Brindha Narasimhamoorthy ◽

...

Keyword(s):

Great Plains ◽

Variance Components ◽

Panicum Virgatum ◽

Biomass Yield ◽

Southern Great Plains ◽

Panicum Virgatum L

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Impact of Growing Environment on Anthracnose Severity of Switchgrass Cultivars and Clones

Plant Disease ◽

10.1094/pdis-01-16-0006-re ◽

2016 ◽

Vol 100 (10) ◽

pp. 2034-2042

Author(s):

Lindsey Hoffman ◽

Laura M. Chaves ◽

Eric N. Weibel ◽

Hilary S. Mayton ◽

Stacy A. Bonos

Keyword(s):

Panicum Virgatum ◽

Biomass Yield ◽

Limited Information ◽

Panicum Virgatum L ◽

Growing Environment ◽

Selection For ◽

The Impact ◽

Clonal Repeatability ◽

Plant Basis ◽

Marginal Soil

Anthracnose (caused by Colletotrichum navitas) has the potential to significantly reduce biomass yield of switchgrass (Panicum virgatum L.); however, limited information is available on the impact of growing environment on tolerance of switchgrass to anthracnose. Therefore, the major objectives of this study were to (i) examine genotype–environment (G × E) effects on anthracnose severity in populations of switchgrass cultivars and individual genotypes and (ii) determine clonal repeatability estimates and stability analysis of anthracnose tolerance on individual switchgrass genotypes. Two experiments were conducted at one prime and two marginal soil locations in New Jersey. In all, 14 switchgrass cultivars were established from seed in 2008 for experiment 1 and 50 replicated switchgrass clones were planted in 2009 for experiment 2 at all three locations. Anthracnose was rated visually in 2010 for experiment 1 and in 2010 and 2011 for experiment 2. Significant G × E interactions were detected for both experiments (P ≤ 0.05) and anthracnose severity varied by location and cultivar. Clonal repeatability estimates for disease tolerance among clones was 0.78 on a clonal basis and 0.32 on a single-plant basis. Lowland ecotypes exhibited less disease overall than upland ecotypes. Results from this study indicate that selection for improved tolerance to anthracnose should be conducted after evaluation across several environments over multiple years.

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