| AbstractBased on muskmelon (Cucumis melo. L) provided by Horticultural Constitute, Xinjiang Agricultural Constitute as experimental materials, through field and inside experiments, the effects of root-zone volume, growing media pH and porosity feature, and concentration of nutrient solution on tray seedling building of muskmelon were studied from leaf ultrastructure, forming and physiological characters. Combined with the correlation analysis, the technical parameters of muskmelon nursery were determined. The main results were as following:1.The effect of root-zone volume on the construction of muskmelon seedling1.1 Effects of root-zone volume on tray seedling of muskmelon were related to seedling age. Under the condition of energy-saving nursery in winter, the effect of root-zone volume was not significant on seedling less than 32 days, but on more than 32 days, there were significantly decreased for the number of leaf, leaf area, root and shoot dry matter per seedling.1.2 The photosynthetic character was also affected by root-zone volume. When it was reduced to the volume 16 ml, chloroplast ultrastructure of the second leaf tended to be broken down, and starch grains were neormously deposited, and the concentration of chlorophyll increased, the transient value of net photosynthetic rate greatly decreased in a day, but the coming time of peak value was 2 hours earlier than other treatments.1.3 Root-zone volume influenced the physiological characters of muskmelon seedling. The N concentration of root and root activity was decreased with reduction of volume from 470ml to 37ml, but the one of shoot was stable. When to volume 16ml, the concentration of these two was increased conversely. The osmotic substances such as proline, soluble protein and sugar were increased with the root-zone volume from 470ml to 16ml.2. The effect of growing media pH on the construction of muskmelon seedling2.1 Growth: The growth was significantly influenced by growing media pH. In the range of pH 5.0 to 5.5 and 7.5 to 8.0, leaf area per leaf, leaf area, root and shoot dry matter, the height and stem diameter per seedling all reduced, especially for seedlings grown in more acidy media. In severe acidy media, tray seedlings showed the growing condition with leaf deep green, and height shorter.2.2 Structure: The acidy media made it to decrease for the cell number of bast, moreover, it was more serious compared with alkaline media. The acidy and alkaline media destroyed the microstructure of chloroplast, and made seedlings aging.2.3 Acidy media caused chlorophyll aggravated in leaf, the total concentration of which was increased, and Ca/Cb decreased, but in alkaline media, the concentration was reduced. The leaf net photosynthetic rate showed the trend of increasing, stable and decreasing with pH rise from 5.0→6.0→7.0→8.0, but it was less serious for alkaline than acidy media. The concentrations of total N and K of shoot were not affected by media pH, but not for ones of the total Fe and Ca. The concentration of total Fe increased, one of total Ca fell in acidy media. Though concentration of POD was increased, MDA was still increased in leaves. The root activity was sensitive to media pH, which was enhanced shortly during the early growth of seedling, but significantly reduced during the late period of growth in acidy media compared to other pH media.3. The study of porosity feature on the construction of muskmelon seedling3.1 The bulk density had correlation to media density, total and air porosity degree, and water- holding content, the correlation of which with healthy index of different stages was more superior to other feathers, therefore, the bulk density was reasonable as the first index of porosity features.3.2 Media temperature was slightly affected by media bulk density, but the transient value of water content in a day was greatly influenced, especially for the treatment with larger bulk density 0.68 g/cm3. 3.3 The proper bulk density was benefit to seedling growing. With the range of bulk d...
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