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Using four Uncariae Cum Uncis materials including Uncaria sinensis (HGT), U. hirsutea (MGT), Jianhe U. rhynchophylla (JHGT) and U. rhynchophylla(GT) as the research objects, the correlations between medicinal materials' yield and photosynthetic ecophysiology-factors in the plant exuberant growth period were studied. Results showed that the Uncaria plants net photosynthetic rate (Pn) changed by unimodal curve. There was not "midday depression" phenomenon. There was a different relationship among the photosynthetic ecophysiology-factors and between photosynthetic ecophysiology-factors and medicinal materials' yield. Pn,Tl,Gs had a significant correlation with medicinal materials' yield（M）and were the most important factors of growth., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Epimedium is a widely used medicinal plants. Due to excessive use of wild resources and resource constraints, artificial cultivation is the only way to achieve sustainable use of resources. E. pseudowushannense is intended to achieve the first cultivated species, but plant production technology is not yet fully mature.The diurnal variation of photosynthetic and eco-physiological characteristics of E. pseudowushannense in different growing age was studied by the CI-340 Portable Photosynthesis System under natural conditions. The net photosynthetic rate (Pn), stomatal conductance (C), intercellular CO2 concentration (Ci), photosynthetically active radiation (PAR), relative humidity (RH), air temperature (Ta), apparent mesophyll conductance (ALMC), transpiration rate (E), leaf temperature (Tl), water use efficiency (WUE) and other photosynthetic physiological factors and environmental factors were measured. The obtained data was analyzed by correlation analysis, path analysis and stepwise multiple-regression analysis to explore the relationship between net photosynthetic rate and physiological and ecological factors. The results show that： ①The daily variation of the Pn, E, ALMC, C of E. pseudowushannense in different growing age took on"two peak type", the Pn was with an obvious midday depression phenomenon at noon.②The Pn, ALMC and C of annuals' were significantly higher than biennial or three-year; but the Ci was basically a three-year > biennial> annual.③The correlation analysis, path analysis and stepwise regression analysis showed that ALMC, Ci, Ta might played important role in the Pn and ranked as ALMC>Ci>Ta., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Objective: To compare the photosynthetic characteristics and medicinal ingredients in different months in order to provide a theoretical basis for cultivation and harvest of Inula nervosa., Methods: The photosynthetic characteristics was measured by using LI-6400 and morphological characteristics were compared in different months, and the contents of total flavonoids and total phenols were determined by UV spectrophotometry., Results: Net photosynthetic rate of Inula nervosa was the highest in June, which showed a single peak curve, and the average of daily change reached to 8.50 μmol/(m2 x s). Light response curve data showed the ability of using the strongest light was in June. Chlorophyll fluorescence parameters values also displayed that, openness of reflect center and photochemical efficiency of leaves' photosystem II were the highest, which also had the fastest rate of electron transfer in June. Morphological indicators showed that the single leaf area and leaf area of Inula nervosa were significantly higher in June than those in other months. The content of total phenols were much higher than that of total flavonoids in Inula nervosa. And the medicinal ingredient content of the underground part was higher than that in the aerial part., Conclusion: The best harvest time of underground part of Inula nervosa should be after autumn, when the weight and active ingredients are accumulated to a considerable level.

Objective: To study the effect of altitudes on the photosynthate accumulation and distribution pattern of Angelic sinensis in Gansu province and provide theontical for its expanding ecological planting region., Methods: Used field test to study the photosynthate accumulation and distribution pattern of Angelic sinensis on three different altitudinal gradients from 2 300 m to 2 800 m., Results: Before September 25, total photosynthate accumulation were decreased with the increasing of elevation, which amaunt was 176 g/plant, 166 g/plant and 128 g/plant, respectively. The total photosynthate of low-altitude and middle-altitude were significantly higher than that of high-altitude (P < 0.05). After September 25, middle-altitude was significantly higher than the other two altitudes (P < 0.05), respectively, by 13.9% and 11.1%. The photosynthate accumulation rate existed the altitude effects, there was no significant difference between high-altitude (46.7%) and middle-altitude (43.7%), but they were even significantly higher than that of low-altitude (33.1%). The root distribution proportion (> 30%) existed the difference, that of high-altitude was 10 days earlier than the other two altitudes, and later that of high-altitude (about 54%) was higher than the other two altitudes (49.8% - 50.9%), it laid the foundation for yield formation. Yield of Angelic sinensis was as follows: middle-altitude (28.4 g/ plant), high-altitude (26.6 g/plant) and low-altitude (21.8 g/plant). Yield of Angelic sinensis middle-altitude and high-altitude were higher than that of low-altitude, respectively, by 30.2% and 22.2%, and it had a significant difference (P < 0.05), this result was consistent with the photosynthate accumulation rate., Conclusion: Altitudinal gradients affect yield formation of Angelic sinensis by changing the photosynthate distribution pattern and dry matter accumulation rate. So by appropriately increasing altitude, the root distribution proportion and yield are improved, this provides theoretical reference for expanding Angelic sinensis planting ecological region.

The regeneration niche is commonly partitioned along a gradient from shade-tolerant to shade-intolerant species to explain plant community assembly in forests. We examined the shade tolerance of tree seedlings in a subtropical coastal forest to determine whether the ecological filtering effect of a dominant, synchronously monocarpic herb (Isoglossa woodii) selects for species at either end of the light response continuum during the herb's vegetative and reproductive phases. Photosynthetic characteristics of seedlings of 20 common tree species and the herb were measured. Seedlings were grown in the greenhouse at 12-14% irradiance, and their light compensation points measured using an open-flow gas exchange system. The light compensation points for the tree species were low, falling within a narrow range from 2.1 ± 0.8 μmol m(-2) s(-1) in Celtis africana to 6.4 ± 0.7 μmol m(-2) s(-1) in Allophylus natalensis, indicating general shade tolerance, consistent with a high and narrow range of apparent quantum yield among species (0.078 ± 0.002 mol CO(2) mol(-1) photon). Rates of dark respiration were significantly lower in a generalist pioneer species (Acacia karroo) than in a forest pioneer (C. africana), or in late successional phase forest species. We argue that the general shade tolerance, and phenotypic clustering of shade tolerance, in many tree species from several families in this system, is a result of ecological filtering by the prevailing low light levels beneath the I. woodii understorey, which excludes most light-demanding species from the seedling community.

A pot experiment was conducted to study the effects of water stress on the photosynthetic characteristics, biomass accumulation, and principal medicinal compositions of Tribulus terrestri. Water stress changed the diurnal variation of T. terrestri photosynthesis, decreased the net photosynthetic rate and transpiration rate significantly, weakened the plant photosynthetic and assimilative capability, and accordingly, hindered the dry matter accumulation and decreased the biomass. However, water stress promoted the accumulation of gross saponins in T. terrestri. In the treatments with irrigation amounts 150 and 450 mm, the gross saponins content was 13.26 and 12.47 mg x g(-1), respectively, being significantly different from that in the treatments with irrigation amounts 250 and 350 mm. The dynamic accumulation of gross flavonoids and gross saponins had an opposite tendency with that of biomass, namely, the contents of these principal medicinal compositions were the lowest when the biomass was the maximal. Correlation analysis showed that the biomass accumulation of T. terrestri was significantly correlated with outside environmental factors, while the contents of secondary metabolism products were affected not only by the outside environmental factors, but also by the inside factors such as biomass accumulation.

American CI-340 portable photosynthesis system was applied to compare the response of the net photosyntheitc rate to the light and the CO2 in Schisandra chinensis form different region and growing situation. The result showed the sample plant from Liaoning had higher light compensate point, higher light saturation point, higher maximum Pn value and higher apparent quantum yield than the sample from Jilin, so it can adapt to the changes of the sunlight in a day better. The weak plant from Jilin had lower light compenstate point, higher light saturation point and higher net photosynthetic rate, so it had stronger availability on light. The stronger one was more sensitive to the weak light. The Jilin sample had higher CE and lower CO2 compensate point compared to that from Liaoning, but when the density of CO2 rised to 240 micromol/mol, the Pn of Schisandra chinensis in Liaoning became much higher than that of Jilin. Under the natural CO2 density condition, the plant from Liaoning had higher photosynthesis ability.

Photosynthetic electron transport and light energy allocation were studied in the alpine plants Anisodus tanguticus (Maxim.) Pascher and Rheum tanguticum Maxim. ex Balf on the Qinghai-Tibet Plateau by using gas exchange and chlorophyll fluorescence. The results indicated that apparent quantum yield (AQY) of leaves of A. tanguticus was marginally higher than that of R. tanguticum although it had a lower maximum net photosynthetic rate (Pmax). The net photosynthetic rate (P(n)) of A. tanguticus was higher than R. tanguticum within the range of middle photosynthetic photon flux density (PPFD). However, the P(n) in R. tanguticum increased concomitantly with PPFD and did not appear to show light saturation of P(n) even under 2000 micromol m(-2) s(-1) which is similar to full light in summer (Fig.1). Increasing the PPFD to 1200 micromol m(-2) s(-1) decreased the ratio of carboxylation rate to total photosynthetic electron flow rate (J(C)/J(F)) although increased the ratio of photorespiration (J(O)/J(F)) for both species. Both J(C)/J(F) and J(O)/J(F) stabilized with a PPFD of more than 1200 micromol m(-2) s(-1) (Fig.2). The changes in the ratios of Rubisco oxygenation to carboxylation (V(O)/V(C)) were similar to changes to J(O)/J(F) (Fig.3). The increase of thermal energy dissipation (D) in A. tanguticus was higher than R. tanguticum with increased PPFD (Fig.4). It can be concluded that the two species adopt different mechanisms to cope with increased solar radiation. Increasing the fractions of PSII thermal energy dissipation and electron transport through photorespiration were the main adaptations in A. tanguticus. Enhancement of photosynthetic capacity with increased PPFD to balance the higher light energy absorbed by leaves is considered the main adaptation for R. tanguticum.

Objective: To study the effect of changing source-sink ratio on dry matter accumulation yield, distribution and interrelated physiological index of Cynanchum bungei., Method: Bud, fruit or side tress of C. bungei were picked artificially in the development stage. LAI, chlorophyll content, photosynthesis of single leaf, accumulation and distribution of dry matter at different and treatments were measured. The untreated plant was used as the control., Result: Although leaf decrease can be compensated by the increasing photosynthesis rate of single leaf, the LAI was small, chlorophyll decomposes quickly and these leaves showed the signs of early ageing. The matter accumulation was lower than that of control. Picking bud and fruit made photosynthesis rate of single leaf descend, chlorophyll decomposes slowly and its content keeps high, that inhibited ageing of the plant obviously. The LAI keeps larger, photosynthate was abundant. Dry matter accumulation and distribution to the root were higher than that of control and that of side tress picked. So, the yield with this treatment increased., Conclusion: Picking bud can increase LAI, postpone the decomposition of chlorophyll, and protract the functional leaves. Consequently, picking bud can add the accumulation of dry matter, increase proportion to radix and improve the yield and economy benefit.

Objective: To study the shade-endurance property of Glycyrrhiza uralensis and provide rationale for the practice of inter-cropping G. uralensis with trees., Method: Black shading nets were used to provide five different environments of light intensities (light penetration rates of 100%, 75%, 65%, 50% and 25%, respectively). To assess the shade-endurance capacity of G. uralensis, several aspects were evaluated, including growth characters, physiological and ecological characters, biomass, and chemical contents., Result and Conclusion: G. uralensis is a light-favored plant. The growth indices such as plant height, stem diameter, leaves number, root diameter, biomass, and daily average photosynthetic rate (Pn) are highest when light permeation rate is 100%. All these indices decrease when light intensity decreases. However, G. uralensis possesses shade-endurance capacity to some degree; it adapts to the shading environment by increasing the leaf area and chlorophyll contents. Shading has no obvious effect on the absolute light energy utilization rate (Eu) or Fv/Fm ratio. The influence of shading on the chemical contents of G. uralensis is obvious.

Objective: To compare and explore the physiological and biochemical index of virus-free seedling and common seedling of Chrysanthemum morifolium., Method: Leaves of virus-free seedling and common seedling were cut down and the contents of chlorophyll a and b, MDA, and the activity of SOD, POD, CAT, and the net photosynthetic rate (Pn) were measured., Result and Conclusion: The contents of chlorophyll and Pn of virus-free seedling were higher than those of common seedling. But were measured, the contents of MDA and the activity of SOD, POD, CAT related to the physiological resistance were lower than the latter. These could explain the phenomenon of virus-free seedling grow better than the common seedling under the same condition.

With LiCor-6400 Portable Photosynthesis System, carbon dioxide exchange pattern for leaves of Dendrobium nobile during 24 hours were studied in sunny day and rainy day, and the variation of CO2 exchange rate to light intensity was analysed. The results showed that in sunny day D. nobile absorbed CO2 in all day except at midday, at noon photorespiration took place. The CO2 exchange pattern was similar to Crassulacean Acid Metabolism(CAM). In rainy day CO2 uptake was in all day, at night CO2 uptake was monitored at 21:00, then CO2 released from 23:00 to dawn. Light saturation point was 1000 mumol/m2s. Over light saturation point photosynthesis, photoinhibition of photosynthesis will be induced by high-light. Exposed to high-light, the light saturation point and the CO2 uptake velocity would be decreased. With variation of environmental factors, photosynthetic pathway in D. nobile could change from CAM to C3 photosynthetic metabolism. It may be one of main reasons for D. nobile to adapt to the shade-requiring environment, the slow growth and rareness in nature.