عنوان مقاله [English]
Parameters recognize different area weather and climatic and effect on the plants one of the best important effect elements is increase products yield. Agro climatic study can state area ability and maximum exploit its. The aim of this research is, recognizing of the ability ecologic potential in different areas for cultivating Brassica napus In Regard To climatic temperature Needs in khorasan provinces. For the purport of general recognizing the region, climatic zoning was done by advanced Demarton method. The date of planting was determined with regard to suitable temperature (mean daily 15 - 20 centigrade) and Wibool formula (with 75 percent probability). The date of various phonological phases was estimated according to growth effected degree day. Climatic needs, optimum and limited temperatures in various phonological phases extracted from different sources and probability of occurrence calculated in the following studied areas. Relationship between main production and optimum and limited temperatures in various phonological phases. Then arrange and constitute temperature layer with used regressions formula. Planting regions classified in to four parts: very favorable (Torbat Haidarie, Ghoochan, Bojnord and Kholmakan), favorable (Birjand, Ghaen, Mashhad, Nishaboor and Ferdoos), relatively favorable (Sarakhs, Kashmar, Khonabad, Torbat Jam and sabzevar) and unfavorable (Boshrooye and Nehbandan).