abstract plants growth and development and physiological activities occur in a certain air temperature range. spit of this fact that zero temperature named as a freezing temperature, in agriculture meteorology, freezing happen in lower temperature which is different for plants that lead to their tissues damage. early autumn freezing cause damage to harvesting of cotton and sugar beet and affect...

Insects that tolerate severe cold during winter may either supercool or tolerate ice forming within the tissues of the body. To compare the relative advantages of freezing and supercooling, we measured rates of CO(2) production and water loss in frozen and supercooled goldenrod gall fly larvae (Eurosta solidaginis). As an important first step, we measured the time required for ice content and m...

OJIP analysis, which explores changes in photosystem II (PSII) photochemical performance, has been used as a measure of plant susceptibility to stress. However, in the case of freezing tolerance and winter hardiness, which are highly environmentally variable, the use of this method can give ambiguous results depending on the species as well as the sampling year and time. To clarify this issue, ...

The insects and microarthropods that vary seasonally in susceptibility to cross-cuticular inoculation by external ice (inoculative freezing) represent a phylogenetically diverse group; however, few studies have explored possible mechanisms experimentally. This study documents seasonally variable inoculative freezing resistance in Dendroides canadensis beetle larvae and combines immunofluorescen...

The various precipitation types formed within winter storms (such as snow, wet snow and freezing rain) often lead to very hazardous weather conditions. These types of precipitation often occur during the passage of a warm front as a warm air mass ascends over a cold air mass. To address this issue further, we used a one-dimensional kinematic cloud model to simulate this gentle ascent (≤10 cm/s)...

Freezing sensitivity of leaves and xylem was examined in four co-occurring Mediterranean oaks (Quercus spp.) grown in a common garden to determine whether freezing responses of leaves and xylem were coordinated and could be predicted by leaf lifespan. Freezing-induced embolism and loss of photosynthetic function were measured after overnight exposure to a range of subzero temperatures in both s...

In deciduous trees, measurement of stem water potential can be difficult during the leafless period in winter. By using thermocouple psychrometry, osmotic water potentials (Ψo; actual Ψo: Ψo(act); Ψo at full saturation: Ψo(sat)) of expressed sap of bark and bud tissue were measured in order to test if the severity of winter desiccation in apple stems could be sufficiently assessed with Ψo. Wate...

Wheat (Triticum aestivum L.) plants change their metabolic state in response to low non-freezing temperatures adjusting the cellular homeostasis for upcoming winter season. The induction of oxidative stress during cold hardening as well as in response to freezing stress and recovery was under investigation in this work. Here we present data about the performance of some enzymes involved in plan...

We compared physiological characteristics and responses to experimental freezing and thawing in winter and spring samples of the wood frog, Rana sylvatica, indigenous to Interior Alaska, USA. Whereas winter frogs can survive freezing at temperatures at least as low as −16C, the lower limit of tolerance for spring frogs was between −2.5C and −5C. Spring frogs had comparatively low levels of the ...

During winter, trees have to cope with harsh conditions, including extreme freeze-thaw stress. This study focused on ice nucleation and propagation, related water shifts and xylem cavitation, as well as cell damage and was based on in situ monitoring of xylem (thermocouples) and surface temperatures (infrared imaging), ultrasonic emissions, and dendrometer analysis. Field experiments during lat...