| Seedling production plays an important role in the industrialized production of peony, which is greatly demanded both in China and abroad. However, peony seedlings have traditionally always been cultivated just in great farmland and been coarsely managed, as a result, the fibre roots of these seedlings were relatively sparse and grew quite slowly, which has leaded to problems such as low quality, long cultivation cycles and different specification of peony seedlings, furthermore, the bad weather resistance ability was low, all these factors above have seriously restricted the export scale of peony seedlings. Good nutrition conditions, easily controlled environment, fine management, high quality of seedlings and relatively uniform specification can be provided by container seedlings cultivation, however, on the other hand, the problems of intertwist of main roots and malformation of root system resulted from container cultivation have seriously affected the absorption of seedlings after they were planted. As the most advanced method of seedling cultivation, root control technology can exactly overcome these defects.In this research, seed-seedlings and grafted seedlings of peony were cultivated through two sorts of root control technology, i.e., air root-control and chemical root-control, in order to find out suitable root-control technology for container seedlings of peony and then provide technology support for industrialized production of peony seedlings.The main results are stated as below:1. Air-rooted pruning containers including net bags (Height 25cm×Diameter 10cm) and "rocket pots" (Height 35cm×diameter 30cm) were respectively used to promote the growth of current-grew seed-seedlings and current-grew grafted seedlings. It was found that root agglomerates were well formed earlier, there were no great changes on the number of the first and second class of lateral roots, but the number of the third class lateral roots was obviously increased, the ramification and thickness of root system were also increased. Through the observation on physiological indexes (chlorophyll, dissoluble sugar of roots and leaves, dissoluble albumen of root and leaves) of seedlings cultivated by rocket pots during May to September, Cultivation in rocket pots can obviously promote the quality of seedlings. 2. Different thickness (0,30,60,120,240mg/L) of cuprum root-control reagents ,i.e., CuAC2 and Cu(OH)2, were used to treat current-grew peony seedlings, from measure of shape indexes (Height, number of leaves, area of leaves, number of root tips, dry weight of over ground part and underground part, ratio of root to shoot),it was found that reagents whose thickness were between 0-120 mg/L can increase root tips and shorten the length of main roots and increase biomass of the plants. Additionally, effects of root control became more obvious along the increasing of thickness of reagents. Chemical root-control reagents with thickness equals or over 240mg/L deterred the growth of plants. In terms of root-control effects:CuAC2 120g/L > Cu(OH)2 120g/L > CuAC2 60g/L > Cu(OH)2 60g/L> CuAC2 30g/L > Cu(OH)2 30g/L > Cu(OH)2 240g/L > CuAC2 240g/L3. Different thickness (0, 0.5, 5,10, 50, 100, 200, 600mg/L) of IBA were used to soak the roots of peony seeds for 24h, and then these soaked seeds were planted into tile pots filled with river sand, after 30 days; and 50 days through respective observation on these indexes including number of lateral roots, the length of lateral roots, livingness of root system, height, weight of dry roots and dry seedlings, it was found that IBA with thickness of 100m/L is optimal to promote the: growth of lateral roots of peony seedlings. Root-pruning together with 100mg/L IBA treatment have accumulative effects on peony lateral roots, but at the same time it was found that effect of IBA treatment and root-pruning on lateral roots have time constraints, therefore, it has not solved the problem of intertwist of root system once for all.
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