drought resistance mechanisms of native and commercial turfgrasses under drought stress: . shoot responses

abstract many uses of landscape and important roll of ground covers aspect turfgrasses caused extensive of this plant in the cities. this study focuses on shoot responses and tolerance of native and commercial turf grasses under drought stress in a factorial experiment based on unbalanced completely random design on the year 2006. the specious that we used in this experiment included (i) commercial tall fescue (festuca arundinacea) (ii) commercial perennial ryegrass (lolium perenne) (iii) native tall fescue population (festuca arundinacea). the drought stress levels included (i) 50%fc (ii) 25% fc (iii) recovery from drought stress and 3 groups of pots that was always in the field capacity condition. the results of this study showed that dry weight decreased 26.4% in 25% fc traits in compare with control traits under severe drought stress. decreased in leaf wide, leaf total area, leaf total length and increase in leaf diameter caused decrease in evaportanspiration under drought stress in festuca genus. parameter of quality change (tq) and decrease in total chlorophyll content was minimum in native tall fescue and maximum in commercial ryegrass, from perfect irrigation to sever drought stress. shoot dry weight, leaf width, total leaf area and total leaf length, visual quality and leaf total chlorophyll content increased 18.2%, 103.3%, 74.4%, 28.8%, 64.1%, 40.8% respectively, and mean leaf diameter decreased 53.2% in compare with sever drought stress condition after 14 days rewatering.