aphids in unsprayed canola (brassica napus linnaeus) fields in isfahan province (central iran) were sampled for two growing seasons, 2011-2013. sampling unit was a whole plant and 20 plants were sampled weekly. in the laboratory, heat-extracting and sub-sampling techniques were used to estimate the density of aphids. to determine the relationship between population growth rate of the aphids and...

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...

given the important role of crop growth indices for explanation of cultivars yield differences in diverse environmental and agronomical circumstances, this experiment was conducted at research field of tarbiat modares university during 2007 growing season. experimental treatments were arranged in split-plot layout based on randomized complete blocks with four replications. in this research, sow...

Climate change affects the demand for energy consumption, especially for heating and cooling buildings. Using daily mean temperature (Tmean) data, this study analyzed the spatiotemporal changes of the starting date for heating (HS), ending date for heating (HE), length (HL) and heating degree day (HDD) of the heating season in central heating zone of China. Over China's central heating zone, re...