| Illicium lanceolatum is a traditional and proper medicinal plant in China. The shikimic acid that is contained in I. lanceolatum has strong functions of anti-inflammatory, analgesic and inhibiting platelet aggregation, arterial and venous thrombosis and cerebral thrombosis, but also as is the intermediates for anti-virus and anti-cancer drugs. This discovery makes I. lanceolatum and other genuses of Illicium L. have been given the unprecedented attentions, and its prospects for the development and utilization are more great. Although I. lanceolatum has broader ecological amplitude, but its wild resources are scattered, the current predatory use and increasing scarcity of wild resources is more strong, which makes the protection and cultivation of its is increasingly urgent. Based on 1-year-old cultivated and potted seedlings of 4 provenances, the 4-year-old cultivations of seedlings of I. lanceolatum growthing under 5 different nature light conditions, through field and laboratory tests research, this study discusses the adaptable difference of ecophysiological responses of 4 different provenances of I. lanceolatum and LA provenance growthing under 5 natural light conditons to environment from two aspects of photosynthetic ecophysiology and water ecophysiology. The results as follows:(1) The obvious diversities of photosynthetic characteristics of 4 provenances seedlings are existed in provenances and different growth stages. LA provenance seedlings have lowest use efficiency of low-light and more higher use efficiency of high-light during the initial and later phase, but with the higher use efficiency of low-light during prosperous phase. WN provenance has middle use efficiency for using low-light and high-light in the whole growth phase, and KH provenance has highest use efficiency for low-light during the prosperous and later phase. Whereas, NP provenance has higher use efficiency of low-light during initial phase, but of high-light during prosperous phase. The photosynthetic characteristics with highest LSPin prosperous phase and lowest LCP in later phase indicate that WN provenance is a good provenance with a widest range of adaptability to illumination. The correlation analysis between Net photosynthetic rate (Pn) and the major environmental factors show that the photosynthetic active radiation (PAR) in the early and prosperous period is not a restricted factor, but in the later period has become a major factor.(2) The diurnal variation of photosynthesis and photosynthetic characteristics of 4-year-old I. lanceolatum seedlings under different light conditions are measured and the results show that they have obvious differences not only because of light conditions variation, there is also a seasonal differences. This difference reflects the photosynthetic physiological adaptation of seedlings to growth environment.The lower mean diurnal value of WUE and SUE of A light treatment shows that the shading is essential during prosperous stage. The more higher mean diurnal value of SUE and more lower its of WUE embody that D light treatment is adaptable to low-light environment. The order of diurnal mean value of Pn for I. lanceolatum seedlings under 5 different light conditions is positively correlative to its of PAR.The comparation of photosynthetic parameters reflect that D light treatment has the lowest LCP, higher AQY and LSP, highest Pmax in initial stage, which illuminates that seedlings under D environment have better light energy utilization efficiency. Whereas, it has the lowest LCP, lower LSP, lower Pmax and higher AQY in prosperous stage, which show that it is greatly adaptable to low-light environment in this stage. For A light treatment, it has lowest LSP, lower LCP and highest AQY in initial stage and has lowest AQY and LSP and highest LCP in prosperous stage, which reveal that seedlings of I. lanceolatum haven't adaptable to entire light environment. So D light treatment is most better cultivation pattern of I. lanceolatum.(3) The pertinency between chlorophyll content, leaf mass per area, leaf nitrogen content and photosynthetic capacity of seedlings of 4 provenance and those under 5 different light conditions is greatly affected by growing season. The seedlings of I. lanceolatum have strong morphological plasticity and are adaptable to low-light conditions by reducing the leaf mass per area.(4) The drought stress test for 4 provenances shows that seedlings of WN provenance have strongest adaptability to water and light conditions, followed by NP provenance. Whereas, the seedlings of LA and KH provenances are more greatly restricted by water condition. The short-time drought stress can improve the value of WUE and SUE at a certain extent. In low-light range (0-200 umol·m-2·s-1), the photosynthetic light-response of seedlings of 4 provenances is mainly affected by soil moisture conditions, and when the photosynthetic active radiation continues to enhancing, the photosynthetic response to light will have been more negatively impacted by the light than water.(5) The illumination cultivation and drought stress tests show that under normal water condition, the seedlings of LA provenance are growing better in a light range of 0-50 umol·m-2·s-1, those of WN provenance are adaptable to the range of 50-75 umol·m-2·s-1, those of KH provenance are growing better above 25 umol·m-2·s-1, and those of NP provenance aren't adaptable to the range of 0-25 umol·m-2·s-1. It also shows that under drought stress, seedlings of WN provenance have widest range of lighting needs, and those of LA provenance can't tolerate drought.In a word, from the viewpoint of photosynthetic ecophysiology and water ecophysiology, WN provenance of I. lanceolatum is a good provenance with strongest adaptability and widest range of light and water conditions, followed by LA provenance. The other important result is that the cultivation mode of inter-planting with 80% canopy density is the most suitable mode for I. lanceolatum, followed by 50% canopy density model of inter-planting.
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