| Lily (Lilium spp.) is pepoles'favorite flower because of its beautiful types of flower ind its wonderful meanings. However, different lily cultivars have different adaptabilities, including upper leaf necroses (ULN) after planting5-7weeks (rapid growth period) in the low temperature and weak light conditions in the north. The ULN of lilies has already become one of the main implications of the quality of cut flowers and potted flowers of lily all over the world at present. But the disease mechanism hasn't been unified view. So, three different ULN sensitive oriental lily hybrids cultivars were screened in the different environmental conditions. Different ULN indexes and physiological indicators in the three lily cultivars were compared and associated analyzed to explore the mechanism of ULN. On this basis, the aquaporin was combined to verify the mechanism of ULN. Finally, different fertilizations were treated on lilies and effectively prevented ULN. It was important for the theoretical and practical value of the occurrence and control of ULN in lilies. The results were as follows:1. It was built for the10screening indexes for oriental hybrids lilies, Asian lilies and'OT' hybrid lilies in the facility planting in the low temperature and weak light condition. According to the ten indexes, sixteen oriental hybrids lilies cultivars were evaluated. The research showed that'Legend','Siberia','Crystal Blanca','Montezuma'and'Sorbonne' and'Red empire'had been selected as tolerent low temperature and weak light lily cultivars. thirteen Asian lilies cultivars were screened. The result showed that'Prato','Tresor','Renoir','Elite'and'Detroit'had been selected as tolerent low temperature and weak light lily cultivars. Twelve'OT'hybrid lilies cultivars were evaluated. The research showed that 'Cocossa','Yelloween','Rexona'and'Conca D.Or' had been chosed as facility Lily Cultivars.2. Three different ULN sensitive oriental lily hybrids cultivars, including Sorbonne'(susceptible),'Montezuma'(moderate resistant) and'the Siberia'(resistant) were screened in the three environmental conditions (S1-S3). Their morphological indexes, the ULN index, physiological indexes and photosynthetic indexes were comparised in4-9weeks after planting to explore the mechanism of ULN. The result showed that the height, leaves area, stem-root length, the distribution of dry matter and the content of calcium in different leaves parts of lilies were decreased significantly in the condition which temperature and humidity changed dramatically (S3). And in the S3, the ULN index of lilies was obviously increased. At the same time, the MDA, soluble sugar, soluble protein, enzyme activity of SOD, CAT and GR of three lily cultivars were significantly increased. In addional, the content of leaf chlorophyll increases slowly, and the stem-root activity reduced. The result showed that environmental conditions which changed dramatically in the temperature and humidity had stressed on the three oriental lily cultivars in the physiological, with different levels'Sorbonne'＞'Montezuma'＞'Siberia'.The correlation analysis result showed that the ULN index of three lily cultivars was very significantly negatively correlated with root activity, chlorophyll (a+b), net photosynthesis (Pn) and water use efficiency (WUE)(P＜0.01), and was significantly negatively correlated with transpiration(Tr) and significantly positively correlated with transpiration intercellular concentration of carbonoxide (Ci)(P＜0.05). The ULN index of three lily cultivars was not significantly correlated with Malondialdehyde (MDA), stomatal conductance (Gs), Chlorophyll fluorescence of photosynthetic system Ⅱ (ΦPs Ⅱ) and photochemical efficiency of PS Ⅱ (Fv/Fm). According to the result, root activity, chlorophyll (a+b), Pn and WUE could become rapid screening indicators to evaluate ULN resistances among different lily cultivars in greenhouse in winter.3. In order to explore the close relationship between the UNL index and aquaporin, it was set different concentration of HgCl2stress on different ULN sensitivity of lilies, including'Sorbonne'and'Siberia'. Their morphological indexes, root growth, the ULN index, physiological indexes and photosynthetic indexes were comparised in4-9weeks after planting to explore the mechanism of ULN. The result showed that the height, leaves area, stem-length, Pn, Tr and WUE were decreased significantly and the ULN index of lilies was obviously increased in the three concentrations of HgCl2. The homologous cloning method was used. PIP1gene of water channel proteins had been cloned by the lily leaves. The importance of the aquaporin was analysed in the water transporting process. The direct relationship of the ULN index and plant aquaporin was found.4. Different fertilizations were treated on oriental lily hybrids. The calcium nitrate (0.2mM) with the biological fertilizer (0.3%) was screened to prevent effectively the ULN. Through different concentrations of rooting powder and media were used. The most suitable concentration was selected. The most suitable media and root-growing paste for 'Sorbonne'which are cultivated in greenhouse are soil.grass carbon,cow dropping,straw (4:1:1:1) and "Zhen gen"(5.0ml L-1). The research provided a theoretical basis for the production of lilies.
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