Evapotranspiration Rates of Eleven Zoysia Genotypes

We compared evapotranspiration (ET) rates for 11 Zoysia genotypes, encompassing two species and their hybrid, maintained at nonlimiting soil moisture under field conditions and in an environmental chamber of high evaporative potential. ET rate relationships to leaf area [leaf extension rate (LER)], canopy resistance [shoot density (SHD)], and internal resistance [abaxial (AB) and adaxial (AD) leaf blade stomatal densities] characteristics were determined. Three-year ET rate means were not significantly different among genotypes in the field study, but ET rates among genotypes differed significantly under the higher evaporative potential of an environmental-chamber study. ET rate was not significantly correlated with LER for either the data from the field or the chamber. ET rates of both types of tests also were not significantly correlated with SHD or AB or AD leaf blade stomatal density. Data from field and environmental-chamber research suggest that differences of individual morphological traits among the 11 zoysiagrasses do not influence the ET rate when measured from minilysimeters maintained at nonlimiting soil moisture.

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Effects of Flurprimidol, Mefluidide, and Soil Moisture on St. Augustinegrass Evapotranspiration Rate

HortScience ◽

10.21273/hortsci.25.4.439 ◽

1990 ◽

Vol 25 (4) ◽

pp. 439-441 ◽

Cited By ~ 6

Author(s):

Robert L. Green ◽

Ki S. Kim ◽

James B. Beard

Keyword(s):

Soil Moisture ◽

Plant Growth ◽

Extension Rate ◽

Stenotaphrum Secundatum ◽

Evapotranspiration Rate ◽

Negative Effect ◽

Turfgrass Quality ◽

Black Plastic ◽

Leaf Extension

The objective of this study was to determine the effects of two plant growth regulators (PGR) and two soil moisture levels (SML) on the evapotranspiration (ET) rate, leaf extension rate (LER), and visual turfgrass quality of `Texas Common' St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] grown under glasshouse conditions in black plastic minilysimeters. Treatments included mefluidide at 0.42 kg·ha-1, flurprimidol at 0.84 kg·ha-1, and no PGR, each grown under optimal (– 0.01 MPa) or suboptimal (– 0.8 MPa) SML. Both flurprimidol and mefluidide significantly affected ET rate, LER, and turfgrass quality, whereas the durations of the responses to both PGR treatments were affected by SML. For both SML, the durations of significant reduction in ET rate, LER, and turfgrass quality were longer for flurprimidol than for mefluidide. Application of either PGR at either SML caused a significant reduction in ET rate averaging 18% and a significant reduction in LER averaging 83%. Flurprimidol was more effective than metluidide in terms of ET rate and LER reduction. However, the considerably longer duration of reduced turfgrass quality of flurprimidol-treated turf was a negative effect. Chemical names used: α-(1 -methylethyl)- α -[4-trifluoromethoxy)phenyl]-5-pyrimidinemethanol (flurprimidol) and N- [2,4-dimethyl-5-[[(trifluoromethyl) sulfonyl]amino]phenyI] acetamide (mefluidide).

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Leaf Blade Stomatal Characterizations and Evapotranspiration Rates of 12 Cool-season Perennial Grasses

HortScience ◽

10.21273/hortsci.25.7.760 ◽

1990 ◽

Vol 25 (7) ◽

pp. 760-761 ◽

Cited By ~ 7

Author(s):

R.L. Green ◽

J.B. Beard ◽

D.M. Casnoff

Keyword(s):

Soil Moisture ◽

Environmental Conditions ◽

Leaf Blade ◽

Stomatal Density ◽

Kentucky Bluegrass ◽

Perennial Grasses ◽

Festuca Rubra ◽

Cool Season ◽

Leaf Surfaces ◽

Moisture Conditions

The objectives of this investigation were to determine the stomatal frequencies of 12 perennial cool-season turfgrasses, encompassing nine species, and their associated evapotranspiration (ET) rates under nonlimiting soil moisture and controlled environmental conditions. Significant differences in stomatal density were found among the 12 cool-season turfgrasses on both the abaxial (P > F = 0.0008) and adaxial (P > F = 0.0009) leaf surfaces. Significant differences (P > F = 0.0007) in ET rates also were found among the 12 cool-season turfgrasses. The Kentucky bluegrass (Pea pratensis L.) cultivars exhibited the highest ET rates, while the fine-leafed fescues (Festuca rubra and longifolia L.) exhibited the lowest rates, except for `Big Horn' sheep fescue (Festuca ovina L.), which exhibited an intermediate ET rate. No significant correlation was found between ET rate and either adaxial or abaxial stomatal density. It was concluded that, under nonlimiting soil moisture conditions, stomatal density was not reliably associated with ET rate.

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Two maize cultivars of contrasting leaf size show different leaf elongation rates with identical patterns of extension dynamics and coordination

AoB Plants ◽

10.1093/aobpla/plaa072 ◽

2021 ◽

Author(s):

Tiphaine Vidal ◽

Hafssa Aissaoui ◽

Sabrina Rehali ◽

Bruno Andrieu

Keyword(s):

Genotypic Variation ◽

Leaf Size ◽

High Rate ◽

Time Interval ◽

Extension Rate ◽

Leaf Production ◽

Maize Cultivars ◽

Plant Environment ◽

The Difference ◽

Leaf Extension

Abstract Simulating leaf development from initiation to maturity opens new possibilities to model plant–environment interactions and the plasticity of plant architecture. This study analyses the dynamics of leaf production and extension along a maize (Zea mays) shoot to assess important modelling choices. Maize plants from two cultivars originating from the same inbred line, yet differing in the length of mature leaves were used in this study. We characterised the dynamics of the blade and sheath lengths of all phytomers by dissecting plants every 2–3 days. We analysed how differences in leaf size were built up and we examined the coordination between the emergence of organs and phases of their extension. Leaf extension rates were higher in the cultivar with longer leaves than in the cultivar with shorter leaves; no differences were found in other aspects. We found that (i) first post-embryonic leaves were initiated at a markedly higher rate than upper leaves; (ii) below ear position, sheaths were initiated at a time intermediate between tip emergence and appearance, while above the ear position, sheaths were initiated at a high rate, such that the time interval between the blade and sheath initiations decreased for these leaves; and (iii) ear position also marked a change in the correlation in size between successive phytomers with little correlation of size between upper and lower leaves. Our results identified leaf extension rate as the reason for the difference in size between the two cultivars. The two cultivars shared the same pattern for the timing of initiation events, which was more complex than previously thought. The differences described here may explain some inaccuracies reported in functional-structural plant models. We speculate that genotypic variation in behaviour for leaf and sheath initiation exists, which has been little documented in former studies.

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Early spring and late autumn response to applied nitrogen in four grasses

The Journal of Agricultural Science ◽

10.1017/s0021859600029051 ◽

1980 ◽

Vol 94 (2) ◽

pp. 443-453 ◽

Cited By ~ 11

Author(s):

D. Wilman ◽

A. A. Mohamed

Keyword(s):

Perennial Ryegrass ◽

Leaf Blade ◽

Unit Area ◽

Total Yield ◽

Early Spring ◽

Late Winter ◽

Number Of Leaves ◽

Four Levels ◽

Leaf Extension ◽

Applied Nitrogen

SummaryThe regrowth of Aberystwyth S. 23 perennial ryegrass, S. 24 perennial ryegrass, S. 59 red fescue and S. 170 tall fescue was studied in field swards, comparing four levels of applied nitrogen, for 8 weeks following a clearing cut. The clearing cuts were in mid-October, mid-February and mid-March in each of 3 years, different plots being used on each occasion.The application of N increased the number of leaf primordia, the number of un-emerged leaves, the rate of leaf emergence and death, leaf blade length, width and weight, sheath length, number of leaves per unit area of ground and proportion of green tissue in total yield. The application of N had little effect on the number of leaves per tiller and tended to reduce weight per unit area of leaf blade. The increase in size, weight and number of leaf blades appeared to be major reasons for the positive effect of applied N on yield, previously reported; and the increase in sheath length contributed to the increase in proportion of yield above 4 cm. Rate of leaf extension was not closely related to yield and was more sensitive to temperature than was yield. Changes during regrowth in blade and sheath length helped to explain changes in weight per tiller, previously reported. The effects of improving weather conditions in late winter/early spring were similar to the effects of applied N: larger, heavier leaf blades, longer sheaths, a taller canopy, a lower proportion of dead material, younger leaves. The length of shoot apex per leaf primordium was relatively constant. Leaves continued to emerge, at a slow rate, in the period December–February. S. 170 had the biggest leaves, particularly in May, and the slowest rate of leaf turnover. Rate of leaf extension was increased by applied N more, on average, in the ryegrasses than in the fescues.

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Effects of microhabitat on leaf traits in Digitalis grandiflora L. (Veronicaceae) growing at forest edge and interior

Archives of Biological Sciences ◽

10.2298/abs1402615k ◽

2014 ◽

Vol 66 (2) ◽

pp. 615-627

Author(s):

J. Kołodziejek

Keyword(s):

Soil Moisture ◽

Leaf Area ◽

Stomatal Density ◽

Leaf Traits ◽

Dry Mass ◽

Forest Edge ◽

Leaf Mass Per Area ◽

Forest Interior ◽

The Mean ◽

Shade Leaves

The morphological, anatomical and biochemical traits of the leaves of yellow foxglove (Digitalis grandiflora Mill.) from two microhabitats, forest interior (full shade under oak canopy) and forest edge (half shade near shrubs), were studied. The microhabitats differed in the mean levels of available light, but did not differ in soil moisture. The mean level of light in the forest edge microhabitat was significantly higher than in the forest interior. Multivariate ANOVA was used to test the effects of microhabitat. Comparison of the available light with soil moisture revealed that both factors significantly influenced the morphological and anatomical variables of D. grandiflora. Leaf area, mass, leaf mass per area (LMA), surface area per unit dry mass (SLA), density and thickness varied greatly between leaves exposed to different light regimes. Leaves that developed in the shade were larger and thinner and had a greater SLA than those that developed in the half shade. In contrast, at higher light irradiances, at the forest edge, leaves tended to be thicker, with higher LMA and density. Stomatal density was higher in the half-shade leaves than in the full-shade ones. LMA was correlated with leaf area and mass and to a lesser extent with thickness and density in the forest edge microsite. The considerable variations in leaf density and thickness recorded here confirm the very high variation in cell size and amounts of structural tissue within species. The leaf plasticity index (PI) was the highest for the morphological leaf traits as compared to the anatomical and biochemical ones. The nitrogen content was higher in the ?half-shade leaves? than in the ?shade leaves?. Denser leaves corresponded to lower nitrogen (N) contents. The leaves of plants from the forest edge had more potassium (K) than leaves of plants from the forest interior on an area basis but not on a dry mass basis; the reverse was true for phosphorus.

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