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estimates of plant and soil water content are critical for maximizing irrigation efficiency in turfgrass management. However, laboratory assessment of leaf relative water content is a time-consuming process, especially when a large number of samples are

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Leaf water potential (LWP). relative water content (RWC), gas exchange rates and 4th-derivative spectra were measured in water-stressed and normally Irrigated plank of Totem' strawberry (Fragaria × ananassa) grown in a growth chamber. CO2 assimilation rate (A) dropped sharply when LWP decreased from -0.5 to -1.2 MPa and almost ceased as LWP fell below -1.5 MPa. There was a significant but more gradual decline of A as RWC decreased form 90% to 55%. An exponential relationship with A was observed across a wide range of LWP and RWC (Rz= 0.64, 0.86, respectively). LWP was more closely related with transpiration and leaf and stomatal conductances than with A and water use efficiency. RWC was highly correlated with all gas exchange parameters.

Under moderate water stress, younger leaves maintain higher RWC and A than older leaves. There was no relationship between LWP and leaf age.

RWC and A were both negatively correlated with peak amplitudes of Ca 684 and Ca 697 and positively correlated with Ca 693 in their 4th-derivative spectra of chlorophyll. LWP had a negative correlation with Cb 640.

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Air temperature and photosynthetically active radiation (PAR) effects on relative water content (RWC), rooting percentage, root count, and root mass of unmisted, subirrigated stem cuttings of two taxa were determined. Leaf RWC of `Charm' chrysanthemum [Dendranthema ×grandiflorum (Ramat.) Kitamura] decreased until roots initiated and then increased, was lower for cuttings at 23 °C photoperiod/14 °C dark than for cuttings at 31 °C photoperiod/22 °C dark, and was lower at 193 than at 69 μmol·m–2·s–1 PAR. Neither temperature nor PAR affected leaf RWC of `Dollar Princess' fuchsia (Fuchsia ×hybrida Hort. ex Vilm.), which increased linearly before and after root initiation. Rooting percentage and root count were higher with photoperiods at 31 °C than at 23 °C for chrysanthemum after 7 days and for fuchsia after 10 days. Although all cuttings of both taxa had rooted after 14 days, root dry mass was higher with photoperiods at 31 °C than at 23 °C regardless of PAR for fuchsia and at 69 μmol·m–2·s–1 PAR for chrysanthemum. Propagators wishing to use subirrigation instead of mist, fog, or enclosure can minimize the decline in leaf RWC before root initiation and increase the number and dry mass of roots of chrysanthemum by using 69 μmol·m–2·s–1 PAR and a 31 °C photoperiod/22 °C dark cycle. Root dry mass of fuchsia also can be increased by the use of high temperature, but differences in rooting were independent of changes in leaf RWC.

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Abbreviations: A, apoplastic water percentage; ∈ avg , average elastic modulus; E max , maximum value of elastic modulus; PV, pressure-volume; RDW, relative dry weight; ROWC, relative osmotic (or symplastic) water content; ROWC 0 , relative osmotic

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≈80 °C for analysis of proline, IAA, cytokinin, and ABA contents. Turfgrass quality, relative leaf water content, leaf wilting, and root growth. Turfgrass quality was rated on a visual scale of 1 to 9 with 9 indicating the best quality (very dark green

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application of distillation water from wild bergamot (bee balm) ( Monarda fistulosa L.) increased the essential oil content, whereas the distillation water of absinthe wormwood ( Artemisia absinthium L.), lavender ( Lavandula vera DC), and wild bergamot

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English walnuts during storage ( Gama et al., 2018 ; Labuza, 1980 ); however, depending on the relative humidity of the storage air, the moisture content and water activity of the English walnuts can increase. Water activity is a ratio of the vapor

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emerged when TRs were stored under increasing relative humidity ( Fig. 3 ); however, the lowest relative humidity imposed was 20%, which is in the upper region of Zone I water binding in seed moisture isotherms ( Priestley, 1986 ). Moisture content of TRs

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acceptable TQ level, and a rating of 9 representing healthy plants with dark green, turgid leaf blades and a dense turf canopy ( Turgeon, 1996 ). Leaf relative water content (RWC) was measured to assess the level of leaf dehydration or water deficit. Leaf RWC

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