The effect of climatic parameters on technology according to the degree of day in Gonabad city

In agricultural climate, it is important to know the climatic characteristics of each region in order to adapt it to the cultivation of each plant and increase production. In the present study, the time of occurrence and temperature thresholds of pistachio tree phenological stages at BBCH scale were determined in the field. Then, using non-parametric Mann-Kendall method and Sense slope test, the trend of changes in the elements of average humidity on the day of completion of each stage, average humidity, average maximum and minimum temperature, average temperature on the day of completion of each stage, average soil temperature, average wind speed, rainfall And sundial at Gonabad station during the statistical period of 1398-1398 on pistachio growth. Findings of this study showed that depending on the degree of day at different possible levels, the length of pistachio biological activity in this region varies from 163 to 198 days and the minimum and maximum total hours of sunshine are required to be 177.57 and 1261. The climatic element limiting the biological activity of pistachio plant as well as other climatic parameters were identified. In the next step, Mann Kendall test was used to examine the trend of climatic elements in different stages of pistachio crop phenology. The results of this study showed that among the climatic parameters of pistachio cultivation, average relative humidity, maximum and minimum temperature, average temperature, wind speed and sundial have a significant increasing trend at the level of 5%.