| Under different light conditions, the effect of different light qualities on the growth, physiological characters, yield and qualities of tomato were studied. The main results were as following: 1. The results showed that under red light the dry matter accumulation, leaf area, chlorophyll content, photosynthetic rate, soluble sugar content and total sugar content were all maximal while the chlorophyll a/b ratio and total nitrogen content were lowest compared with the other treatments. The stem diameter, leaf area, root activity and photosynthetic rate of tomato seedlings with blue light were higher than that of white light. The healthy index of the seedling treated by blue light was maximal, and the red light treatment was the second. It is concluded that blue light or red light treatment could accelerate the growth of tomato seedlings, and benefit the breeding of healthy seedling. 2. The activities of peroxidase, superoxide dismutase and ascorbate peroxidase were all promoted under red light illumination, as well as blue light illumination. But the activity of catalase was not influenced significantly. 3. The seedlings were sensitive to low temperature stress. For instance, such indexes as chilling injury index, leaf electrolytic leakage, MDA content and SOD,POD, CAT activity improved , and such indexes as AQY, photosynthesis rate, Fv/Fm and ФPSⅡdecreased . But the decreased ranges of seedlings treated with blue or red light were slight and their activities still kept at a higher level. 4. The difference of plant growth among the treatments were remarkable when firstly seedling transplanted. Under red light the growth quantum was more higher, both the plant height and leaf area were all obviously higher than white and blue light treatments. For the smaller leaf area and the lower photosynthetic rate, the way corp growing of seedlings was weak, which were treated with green or yellow light. But the difference began diminishing when... |
