Effects of Water Deficit on Fluorescence Parameters of Different Wheats Ploids Influence of water turbidity on growth of the seedlings of Potamogeton cripus Effects of Seawater Stress on Photosynthetic and Antioxidant Characteristics in Portulaca oleracea Effects of Exogenous Salicylic Acid on Seedling Growth,Photosynthetic and Chlorophyll Fluorescent Parameters in Melon Seedlings under Cadmium Stress LATE-GROWTH PHOTOSYNTHETIC CHARACTERISTICS AND GRAIN YIELD OF DIFFERENT WHEAT EVOLUTIONARY MATERIALS