Effects of Different Treatments on Chilling Injury and Antioxidative Metabolism in Sweet Potato Photosynthetic Characteristics and Antioxidative Metabolism of Flag Leaves in Responses to Shading during Grain Filling in Winter Wheat Cultivars with Different Spike Types Effects of Carbon Monox ide on Va se L ife and Antiox ida tive Metabolism inCut Rose Flower Effects of Carbon Monox ide on Va se L ife and Antiox ida tive Metabolism inCut Rose Flower