The Research Of Drought Resistance To Annual Ryegrass,tall Fescue And Hybrid Festuloium

Summary:The germination characteristics of perennial ryegrass"festuloium (festucoid type) Hykor","festuloium(Italian ryegrass type) Perny","annual ryegrass Surrey","annual ryegrass Angus"," tall fescue fawn"under the osmotic of polyethylene glycol 6000(PEG-6000) are researched to evaluate the seed drought resistance in the morphological changes,physiological responsibilities under the continuous drought stress. The index relationships under the irrigation and drought stress were analysed and a comprehensive evaluation on physiological indexes of five plants was tried to provide the theoretical basis of germplasm characteristics and breeding for grass or turf grass. The results were as follows:(1) Vagermination rate of all varieties fall expect festuloium Perny, tall fescue fawn and annual ryegrass Angus, theirs raised in low-grade(5%) intimidation, seminal vagermination rate descend with intimidate degree's aggravation in some drought degree.(2) The growths of radicel and plumule were inhibited to some extent. The relative length of radicel and plumule are both decreased with the increase of the osmotic stress. The relationships among stress intensity and relative radicel length, relative plumule length were significant.(3) The chlorophyll content and the rate of green leaf of the five plants were decreased with the stress of continuous soil drought.(4) The proline, soluble sugar and membrane permeability increased comparing with antitheses, meanwhile, increased with the intensive drought degree and time. The content change of praline could be the physical index of drought resistance capacity.(5) The relative water contents of leaves in 5varieties fell with aggravation of drought resistance. Five leaves were treated in different stress phrases in twenty eight days with a seven-day interval, and the water loss rate of leaves without body increased with time when past 2 hours, 4 hours and 6 hours, and the biggest variation was on the 14th day of drought together with 2 hours leave time.(6) The soil water content declined because of the soil evaporation and plants transpiration.