The geographical distribution of growing degree-days (GDDs) within Iran was studied using GIS-based maps. GDDs were calculated using daily thermal parameters (daily maximum and minimum air temperature). Based on the purpose of the study and climatic conditions of Iran, the average value of 5?C was chosen for GDD calculation. The calculations were carried out using daily weather data of 113 mete...

to assess required growing degree days (gdd) for phenological stages of four clover species in different planting dates a field experiment was conducted in 2010-11 and 2011-12 cropping seasons in seed and plant improvement institute in karaj, iran. three planting dates (14 september, 28 september and 13 october) and six clover varieties were assigned to main plots and sub-plots, respectively, a...

Development of wheat (Triticum spp.) is primary driven by temperature, but is also affected by other factors such as vernalization and photoperiod. Crop growth and development are often described in terms of calendar days. However, determining the development in terms of thermal time or physiological time is more accurate because it is an accumulation of the caloric energy needed for the o...

Wheat (Triticum aestivum) production in the rainfed area of Pothwar Pakistan is extremely vulnerable to high temperature. The expected increase in temperature due to global warming should result in shorter crop life cycles, and thus lower biomass and grain yield. Two major factors control wheat phenological development: temperature and photoperiod. To evaluate wheat development in response to t...

Stems or roots + stems of potted, 2-year-old paper birch (Betula papyrifera L.) were subjected to simulated winter thaws of various durations in climate-controlled chambers. The simulated thaws induced dieback of shoots of the treated plants. Although the stem thaw treatment did not significantly increase dieback, there were significant (P < 0.05) correlations between growing degree days above ...

the geographical distribution of growing degree-days (gdds) within iran was studied using gis-based maps. gdds were calculated using daily thermal parameters (daily maximum and minimum air temperature). based on the purpose of the study and climatic conditions of iran, the average value of 5?c was chosen for gdd calculation. the calculations were carried out using daily weather data of 113 mete...

Irrigated agriculture is facing a serious problem of water scarcity, which could be mitigated by optimizing the application regulated deficit irrigation (RDI) strategies. For this reason, aim our study was to determine thresholds based on direct status indicators apricot trees under RDI maximize productivity. Three treatments were tested: (i) Control (CTL), irrigated at 100% crop evapotranspira...