Locating areas prone to infection with Ivy-leaved morning glory (Ipomoea hederaceae Jacq) in germination stage: a new entrant's weed in arable lands of Golestan Province

Access to weed distribution maps can be very useful in planning their management. Locating areas prone to infection with new entrant weeds is needy to knowledge of ecological characteristics of these plants such as cardinal temperatures, EC and pH. In order to investigate the effects of temperature on germination and determine the main germination temperatures (base temperature, optimum and ceiling for germination) of ivy-leaved morning glory, seeds incubated at 10, 15, 17, 20, 25, 30, 35 and 40 0C. To determine the cardinal temperatures, Original beta, Modified beta, segmented and dent like models were used. The results indicated that the original beta model was superior than the other models and base, optimum and ceiling temperatures for seed germination were 10, 25.91 and 41.22 0C respectively. The results showed that ivy-leaved morning glory has high tolerance ability to soil salinity. So, germination percent of this plant can be reduced by 50% in salinity of 45dS.m-1. In addition, germination present of these plants in acidic pH was higher than the alkaline pH. Distribution maps indicated that there were no limitations regarding temperatures and EC for germination and establishment of this weed through the Golestan Province. But regarding pH, there is a major in increasing distribution extent in the province. So that only a small section of Kalaleh and Galikesh lands are suitable in this regard.