Establishment of High-efficiency Regeneration System of Leaf Explants of Eucalyptus grandis Clone EG5 Preparation of curcumin-(oleic acid)2 loaded mPEG5000-PLGA nanoparticles by modified solvent evaporation method Regulatory effects of salicylic acid on protease Deg5 and PSⅡfunction of wheat chloroplasts under heat and high light stress