3D Lanthanide Neodymium Porphyrin Metal-Organic Framework for Photocatalytic Oxidation of Styrene.

A novel three-dimensional lanthanide porphyrin-based MOF (Nd-PMOFs) was synthesized by using tetracarboxyphenyl porphyrin as the ligand and the lanthanide Nd as the coordination metal. Its specific crystal structure information was obtained by single-crystal diffraction with the space group C2/c and the empirical formula C72H45N6Nd2O15.25. This new Nd porphyrin-based MOF with an organic framework formed by a unique coordination method enables the effective separation of photogenerated electrons and holes under photoluminescence, giving it excellent photocatalytic property which could be verified by the characterization data. The photocatalytic performance was examined by taking tert-butyl hydroperoxide as the oxidant and Nd-PMOFs as the catalyst for photocatalytic oxidation of styrene to benzaldehyde with 91.4% conversion and 81.2% benzaldehyde selectivity under optimal reactions, which surpasses most of the results reported in the literature. Several styrenes with other substituents were screened to explore the general applicability of Nd-PMOF for photocatalysis of styrene, among which Nd-PMOFs also exhibited excellent photocatalytic performance. This work offers the possibility to apply lanthanide organometallic frameworks, which are widely used in fluorescent materials, to photocatalysis. In addition, it also provides a new method for the catalytic generation of benzaldehyde from styrene that is consistent with the needs of modern green development.

Comparative transcriptome analysis of a fan-shaped inflorescence in pineapple using RNA-seq.

Pineapple plant usually has a capitulum. However, a fan-shaped inflorescence was exceptionally evolved in pineapple, having multiple crown buds. In order to reveal the molecular mechanisms of the formation of the fan-shaped inflorescence, fruit traits and the transcriptional differences between the fan-shaped inflorescence and the wild-shaped inflorescence pineapples were analyzed in three tissues, i.e., the flower stem apex, the base of the inflorescence, and the inflorescence axis. The weight (i.e., individual yield) of fan-shaped fruit is 4.5 times that of wild-shaped fruit；and non-significant difference in soluble solids, soluble sugar, titratable acid, and Vitamin C was found. Between the fan-shaped inflorescence and wild-shaped inflorescence, a total of 5370 differentially expressed genes were identified across the three tissues. Of these genes, there were 489 overlapping differentially expressed genes in all three tissue comparisons. Between the two pineapples, functional analysis indicated that 444 transcription factors and 206 inflorescence development-related genes were differentially expressed in at least one tissue comparison, while 45 transcription factors and 21 inflorescence development-related genes were overlapped across three tissues. Among the 489 overlapping differentially expressed genes in the three tissue comparisons, excluding the inflorescence development-related genes and transcription factors, 80 of them revealed a higher percentage of involvement in the biological processes relating to response to auxin, and reproductive processes. RNA-seq value and real-time quantitative PCR analysis exhibited the similar gene expression patterns in the three tissues. Our result provided novel cues for understanding the molecular mechanisms of the formation of the fan-shaped inflorescence in pineapple, making a valuable resource for the study of plant breeding and the speciation of pineapple.

Source-sink manipulations differentially affect carbon and nitrogen dynamics, fruit metabolites and yield of Sacha Inchi plants.

BACKGROUND: Being a promising tropical woody oilseed crop, the evergreen and recurrent plants of Sacha Inchi (Plukenetia volubilis L.) has complex phenology and source-sink interactions. Carbon source-sink manipulations with control and two treatments (reduce source, ca. 10% mature leaf pruning; reduce sink, 10% fruitlet thinning) were conducted on 2.5-year-old field-grown P. volubilis plantation during the early-wet season in a seasonal tropical area. RESULTS: Leaf photosynthetic rate and specific leaf area largely remained unchanged in response to defoliation or defloration. Compared with control, higher N contents on average were observed in both remaining leaves and branches of the defoliated plants, suggesting that N-mobilization was mainly due to the enhanced N uptake from soil. Carbon, but not N, is a source-driven growth process of P. volubilis plants, as defoliation reduced the contents of non-structural carbohydrates (especially sugar) in branches, although temporally, whereas defloration increased available C reserve. The seasonal dynamic pattern of fruit ripening was altered by source-sink regulations. Total seed yield throughout the growing season, which depends on fruit set and retention (i.e., number of matured fruit) rather than individual fruit development (size), was slightly increased by defloration but was significantly decreased by defoliation. Compared with control, defloration did not enrich the KEGG pathway, but defoliation downregulated the TCA cycle and carbohydrate and lipid metabolisms in fruitlets after 24 days of the applications of source-sink manipulation. CONCLUSION: Carbohydrate reserves serve to buffer sink-source imbalances that may result from temporary adjustment in demand for assimilates (e.g., defloration) or shortfalls in carbon assimilation (e.g., defoliation). Defoliation is disadvantageous for the yield and also for carbohydrate and lipid accumulation in fruits of P. volubilis plants. Although more studies are needed, these results provide new insights to the further improvement in seed yield of the strong source-limited P. volubilis plants by source/sink manipulations.

Comparative physiological and biochemical mechanisms of salt tolerance in five contrasting highland quinoa cultivars.

BACKGROUND: Chenopodium quinoa Willd., a halophytic crop, shows great variability among different genotypes in response to salt. To investigate the salinity tolerance mechanisms, five contrasting quinoa cultivars belonging to highland ecotype were compared for their seed germination (under 0, 100 and 400 mM NaCl) and seedling's responses under five salinity levels (0, 100, 200, 300 and 400 mM NaCl). RESULTS: Substantial variations were found in plant size (biomass) and overall salinity tolerance (plant biomass in salt treatment as % of control) among the different quinoa cultivars. Plant salinity tolerance was negatively associated with plant size, especially at lower salinity levels (< 300 mM NaCl), but salt tolerance between seed germination and seedling growth was not closely correlated. Except for shoot/root ratio, all measured plant traits responded to salt in a genotype-specific way. Salt stress resulted in decreased plant height, leaf area, root length, and root/shoot ratio in each cultivar. With increasing salinity levels, leaf superoxide dismutase (SOD) activity and lipid peroxidation generally increased, but catalase (CAT) and peroxidase (POD) activities showed non-linear patterns. Organic solutes (soluble sugar, proline and protein) accumulated in leaves, whereas inorganic ion (Na+ and K+) increased but K+/Na+ decreased in both leaves and roots. Across different salinity levels and cultivars, without close relationships with antioxidant enzyme activities (SOD, POD, or CAT), salinity tolerance was significantly negatively correlated with organic solute and malondialdehyde contents in leaves and inorganic ion contents in leaves or roots (except for root K+ content), but positively correlated with K+/Na+ ratio in leaves or roots. CONCLUSION: Our results indicate that leaf osmoregulation, K+ retention, Na+ exclusion, and ion homeostasis are the main physiological mechanisms conferring salinity tolerance of these cultivars, rather than the regulations of leaf antioxidative ability. As an index of salinity tolerance, K+/Na+ ratio in leaves or roots can be used for the selective breeding of highland quinoa cultivars.

The Facile Synthesis of Branch-Trunk Ag Hierarchical Nanostructures and Their Applications for High-Performance H2O2 Electrochemical Sensors.

A novel branch-trunk Ag hierarchical nanostructure was synthesized via a galvanic replacement reaction combined with microwave-assisted synthesis using Te nanowire as a sacrificial template. The Te nanowire was synthesized via a hydrothermal process. We further investigated the potential application of the obtained hierarchical nanostructures in electrochemical sensor analysis. The results showed that the as-prepared sensor exhibited a wide linear range with 0.05 µM to 1.925 mM (R = 0.998) and the detection limit was estimated to be 0.013 µM (S/N = 3). These results indicate the branch-truck Ag hierarchical nanostructures are an excellent candidate material for sensing applications.

Knockdown of Long Noncoding RNA 01124 Inhibits the Malignant Behaviors of Colon Cancer Cells via miR-654-5p/HAX-1.

Background: Previous studies have shown that long noncoding RNAs (lncRNAs) play a key role in cancer, including colon cancer (CC). However, the exact role of long noncoding RNA 01124 (LINC01124) in CC and its mechanisms of action remain unknown. In this study, we investigated the functional effects and the possible mechanism of LINC01124 in CC. Methods: We first determined the expression of LINC01124 in CC tissues (The Cancer Genome Atlas (TCGA) database) and cell lines (quantitative real-time polymerase chain reaction (qRT-PCR)). Functional analysis via Cell Counting Kit-8 (CCK-8), colony formation, cell cycle, wound healing and Transwell assays were performed, and a mechanistic experiment was performed with the western blotting. The function of LINC01124 was also determined in vivo using nude BALB/c mice. Results: The results showed that LINC01124 was upregulated in CC tissues and cell lines. Functional studies showed that knockdown of LINC01124 significantly suppressed the proliferation, migration, and invasion of colon cancer cells in vitro and in vivo. Subsequent mechanistic experiments indicated that LINC01124 acted as a sponge to suppress microRNA 654-5p, which targeted HAX-1. Downregulation of LINC01124 decreased the expression of HAX-1, and overexpression of the miR-654-5p inhibitor attenuated the sh-LINC01124-induced inhibition of CC cell proliferation, migration, and invasion. Conclusion: Collectively, this study revealed that the knockdown of LINC01124 inhibited the malignant behaviors of CC via the miR-654-5p/HAX-1 axis, suggesting that LINC01124 might be a therapeutic target for CC treatment.

[Effects of nitrogen application rate on the growth traits in seedlings of different quinoa cultivars]. / 施氮量对不同藜麦品种幼苗生长的影响.

Effects of five different nitrogen application rates (i.e., N0, 0 g·kg-1; N1, 0.05 g·kg-1; N2, 0.1 g·kg-1; N3, 0.15 g·kg-1; N4, 0.2 g·kg-1) on the growth of seedlings of eight different quinoa cultivars were investigated in a pot experiment. The results showed that: 1) Across different nitrogen application rates, cultivar GB22 and OY had the highest biomass, but cultivar B2 had the lowest value. The highest flower mass ratio, stem mass ratio, root mass ratio, and leaf mass ratio were found in cultivar B2, GB22, R1, and W23, respectively. 2) The rate of nitrogen application significantly affected seedling growth. Compared with the control (N0), the maximum net photosynthetic rate and biomass accumulation were significantly higher in the lower nitrogen applications (i.e., N1 and N2 treatments), but were lower in the higher nitrogen applications (i.e., N3 and N4 treatments). The significant interactions between cultivar and nitrogen application rate on plant biomass indicated that different quinoa cultivars responded differently to nitrogen rate. The optimum nitrogen application rate (Nopt) required for cultivar R1, MY11, GB22 and OY was 0.05 g·kg-1; while that of cultivar GB11, DB, and B2 was 0.1 g·kg-1; but for cultivar W23, Nopt was less than 0.05 g·kg-1. 3) The interactions between cultivar and nitrogen application rate significantly affected biomass allocation. Below the highest nitrogen rate used (i.e., less than 0.2 g·kg-1), the flower and leaf biomass allocation increased with the increasing nitrogen rates. 4) Across different cultivars and nitrogen application rates, plant biomass was positively correlated to the maximum net photosynthetic rate, plant height, ground diameter, and specific leaf area, respectively. These results provided valuable information for the nutrition management of different quinoa cultivars.

Seasonal differences in leaf-level physiology give lianas a competitive advantage over trees in a tropical seasonal forest.

Lianas are an important component of most tropical forests, where they vary in abundance from high in seasonal forests to low in seasonal forests. We tested the hypothesis that the physiological ability of lianas to fix carbon (and thus grow) during seasonal drought may confer a distinct advantage in seasonal tropical forests, which may explain pan-tropical liana distributions. We compared a range of leaf-level physiological attributes of 18 co-occurring liana and 16 tree species during the wet and dry seasons in a tropical seasonal forest in Xishuangbanna, China. We found that, during the wet season, lianas had significantly higher CO(2) assimilation per unit mass (A(mass)), nitrogen concentration (N(mass)), and delta(13)C values, and lower leaf mass per unit area (LMA) than trees, indicating that lianas have higher assimilation rates per unit leaf mass and higher integrated water-use efficiency (WUE), but lower leaf structural investments. Seasonal variation in CO(2) assimilation per unit area (A(area)), phosphorus concentration per unit mass (P(mass)), and photosynthetic N-use efficiency (PNUE), however, was significantly lower in lianas than in trees. For instance, mean tree A(area) decreased by 30.1% from wet to dry season, compared with only 12.8% for lianas. In contrast, from the wet to dry season mean liana delta(13)C increased four times more than tree delta(13)C, with no reduction in PNUE, whereas trees had a significant reduction in PNUE. Lianas had higher A(mass) than trees throughout the year, regardless of season. Collectively, our findings indicate that lianas fix more carbon and use water and nitrogen more efficiently than trees, particularly during seasonal drought, which may confer a competitive advantage to lianas during the dry season, and thus may explain their high relative abundance in seasonal tropical forests.

Yield and resource use efficiency of Plukenetia volubilis plants at two distinct growth stages as affected by irrigation and fertilization.

This study is to test how seedlings (vegetative) and large plants (reproductive) of an oilseed crop (Plukenetia volubilis) responded to regulated deficit irrigation techniques (conventional deficit irrigation, DI; alternative partial root-zone irrigation, APRI) in a tropical humid monsoon area. Seedlings were more sensitive to water deficit than large plants. Although APRI did better than DI in saving water for both seedlings and large plants at the same amount of irrigation, full irrigation (FI) is optimal for faster seedling growth at the expense of water-use efficiency (WUE). The seed number per unit area was responsible for the total seed oil yield, largely depending on the active process of carbon and nitrogen storages at the whole-plant level. The magnitude of the increase in total seed and seed oil yield by fertilization was similar under different irrigation regimes. Compared with FI, DI can save water, but reduced the total seed yield and had lower agronomic nutrient-use efficiency (NUEagr); whereas APRI had similar total seed yield and NUEagr, but reduced water use greatly. Although the dual goal of increasing the yield and saving water was not compatible, maintaining a high yield and NUEagr at the cost of WUE is recommended for P. volubilis plantation in t he water-rich areas.

[Variation patterns of Coptis teeta biomass and its major active compounds along an altitude gradient].

An investigation was made on the biomass and major active compounds of wild and cultivated Coptis teeta along an altitude gradient in Nujiang of Yunnan. The results showed that the rhizome and root biomass of wild C. teeta increased from the altitude 2100 m to 2700 m, but the difference was not significant. The rhizome biomass of cultivated C. teeta was 87.5 kg x hm(-2) at 2600 m and 97.0 kg x hm(-2) at 2700 m, being much higher than 34.8 kg x hm(-2) at 2300 m (P < 0.05). At the same altitudes (2300 m, 2600 m, and 2700 m), cultivated C. teeta had higher rhizome and root biomass than wild C. teeta, but the difference was not significant. There was a significant positive correlation between the rhizome and root biomass and the whole plant biomass of wild C. teeta. Wild C. teeta had the highest content of berberine in rhizome (4.60%) and root (1.93%) at 2700 m, plamatinein in rhizome, and jatrorrhizine in rhizome and root at 2600-2700 m, and plamatinein in root at 2 300 m; while cultivated C. teeta had the highest content of berberine in rhizome (4.41%) and root (1.90%) at 2600 m, plamatinein in rhizome and root, and berberine and jatrorrhizine in root at 2600-2700 m, and jatrorrhizine in rhizome at 2300 m. The content of major active compounds in wild C. teeta rhizome and root were significantly higher at 2600 m and 2700 m than at 2100 m and 2300 m (P < 0.05), and the rhizome biomass, root biomass, leaf biomass, total biomass, height, and canopy diameter of wild C. teeta ramet increased first and decreased then from the altitude 2100 m to 2700 m. Increasing planting density and enhancing artificial management could improve the biomass of C. teeta and its major active compounds concentrations.

Seedling growth strategies in Bauhinia species: comparing lianas and trees.

BACKGROUND AND AIMS: Lianas are expected to differ from trees in their growth strategies. As a result these two groups of woody species will have different spatial distributions: lianas are more common in high light environments. This study determines the differences in growth patterns, biomass allocation and leaf traits in five closely related liana and tree species of the genus Bauhinia. METHODS: Seedlings of two light-demanding lianas (Bauhinia tenuiflora and B. claviflora), one shade-tolerant liana (B. aurea), and two light-demanding trees (B. purpurea and B. monandra) were grown in a shadehouse at 25% of full sunlight. A range of physiological, morphological and biomass parameters at the leaf and whole plant level were compared among these five species. KEY RESULTS: The two light-demanding liana species had higher relative growth rate (RGR), allocated more biomass to leaf production [higher leaf mass fraction (LMF) and higher leaf area ratio (LAR)] and stem mass fraction (SMF), and less biomass to the roots [root mass fraction (RMF)] than the two tree species. The shade-tolerant liana had the lowest RGR of all five species, and had a higher RMF, lower SMF and similar LMF than the two light-demanding liana species. The two light-demanding lianas had lower photosynthetic rates per unit area (A(area)) and similar photosynthetic rates per unit mass (A(mass)) than the trees. Across species, RGR was positively related to SLA, but not to LAR and A(area). CONCLUSIONS: It is concluded that the faster growth of light-demanding lianas compared with light-demanding trees is based on morphological parameters (SLA, LMF and LAR), and cannot be attributed to higher photosynthetic rates at the leaf level. The shade-tolerant liana exhibited a slow-growth strategy, compared with the light-demanding species.

[Response of stomatal characteristics and its plasticity to different light intensities in leaves of seven tropical woody seedlings].

Stomatal characteristics and its plasticity in leaves of four canopy species, Shorea chinensis, Pometia tomentosa, Anthocephalus chinensis, Calophyllun polyanthum and three middle-layer species, Barringtonia pendula, Garcinia hanburyi, Horsfieldia tetratepala acclimated to different light conditions (8%, 25%, 50% and 100% of full sunlight) for more than one year were surveyed. All plant's stomata were distributed on the abaxial of leaves. Pometia tomentosa and Barringtonia pendula had higher stomatal density, and the guard cell length of Anthocephalus chinensis and Calophyllun polyanthum were much greater than others'. Stomatal density and stomatal index (ratio of stomatal numbers to epidermal cell number) were increased with growth irradiance increased, while numbers of stomata per leaf were higher in the low than the high relative PFD, and stomatal conductance of leaves was the highest in the 50% of sunlight except for Anthocephalus chinensis. The relative PFD had little effects on the guard cell length of all seven plants. There was a significant negative correlation between stomatal density and leaf area, but the stomatal conductance was not significantly positive with the stomatal conductance in some degree. The analysis of phenotypic plasticity of stomatal characteristics showed that plasticity index for stomatal index and numbers of stomatal per leaf were similar for canopy and middle-layer species, while the plasticity index of stomatal density and stomatal conductance were significantly greater for canopy species than middle-layer species. The high plasticity of canopy species was consistent with the hypothesis that specialization in a more favorable environment increases plasticity.

[Effect of low nocturnal temperature stress on fluorescence characteristics and active oxygen metabolism in leaves of Garcinia hanburyi seedlings grown under two levels of irradiance].

The fluorescence characteristics and active oxygen metabolism in leaves in Garcinia hanburyi seedlings grown under two irradiance levels (50% and 8% of full natural sunlight) and nocturnal low temperature (4 degrees C) were studied in Xishuangbanna. The results showed that the photochemical efficiency of PS II (Fv/Fm), the quantum yield of PS II linear electron transport (phi PS II) and non-photochemical quenching (NPQ) were decreased, but the initial fluorescence yield (F0) were increased with prolonged stress time of low temperature in leaves of Garcinia hanburyi grown under the two different irradiance levels. After three days of recovery treatment, the Fv/Fm and F0 of Garcinia hanburyi grown under 50% natural irradiance were not recovered completely, while those of the seedlings grown in 8% natural irradiance were recovered almost completely, which indicated that the photosynthetic apparatus of Garcinia hanburyi grown under 50% irradiance was injured by photooxidation, but that of seedlings grown in 8% irradiance was only reversibly inactivated by the nocturnal low temperature stress. In the mean time, although the activities of protective enzymes (SOD, CAT, and APX) increased, the O2-. production rate and H2O2 content also increased with the duration of the stress. The MDA also accumulated in leaves of Garcinia hanburyi grown under two different irradiance levels. After three day's recovery, much less active oxygen was produced in leaves of Garcinia hanburyi grown under 8% than that under 50% irradiance. The implication of the results for practice were also discussed.

[Effects of fertilization on the growth, photosynthetic characteristics and yield of Coffea arabica].

Coffea arabica is a major economic plant in agriculture plantation in tropical and subtropical areas in the world. This paper reports the experimental results on the fertilization strategy in Yunnan, China. Effects of varied levels of nitrogen (N), phosphorus (P), potassium (K) nutrients on the growth, photosynthetic characteristics and yield in three-year old saplings of C. arabica with the density of 4500 individuals per hectare were measured. In general, N is the most important factor influencing the growth, photosynthetic capacity and yield of C. arabica, followed by K and P, respectively. The yield can be improved through spraying appropriate amount of trace elements in the leaves. The optimum matching experiments in fertilization level of N:P2O5: K2O is at the ratio of 1:0.5:1. The high yield of C. arabica need high nutrient demands, but the optimum amount of fertilizer of N, P2O5, K2O is 100, 50, 100 g per individual according to the cost-benefits analysis. The yield of C. arabica was closely related with the numbers of branch, total leaf areas and maximum rate of net photosynthesis (Amax) among different treatments. Different fertilization strategy had no significantly effects on the photochemical efficiency in dawn, but all indicators showed that the higher-fertilized plants could significantly alleviate diurnal photoinhibition.

[Acclimation of foliar photosynthetic apparatus of three tropical woody species to growth irradiance].

The photosynthetic characteristics and protective role of leaf antioxidant systems were studied for seedlings of three woody species, Anthocephalus chinensis, Barringtonia pendala, Garcinia hanburyi, acclimated to 8%, 25%, 50% of natural sunlight for four months. As growth irradiance increased, the saturation points, the light compensation points of photosynthesis, the maximum net photosynthetic rate, and the non-photochemical quenching efficiency of three species were increased, while the apparent quantum yield (AQY), the effective quantum efficiency (Fv'/Fm'), and the photochemical quenching efficiency (qP) were decreased. In protective enzymes systems, SOD and APX activities increased with increasing growth irradiance, but CAT activity was not consistent with PFD. AsA exhibited the most dramatic increase in response to growth irradiance. It could be concluded that besides the increase in xanthophyll cycle-dependent energy dissipation, the enhancement of leaf antioxidants was also a protective pathway against high light intensity.

[Growth and photosynthetic characteristics of field-grown Coffea arabica under different watering and fertilization managements].

Straw mulching and drip irrigation have been widely used for coffee production. In order to know if these techniques are suitable in Yunnan, five-year-old coffee plants were separated into 8 groups to grow in the field under 2 fertilization rates (low and high) and 4 watering regimes: dry straw mulching (M), drip irrigation (I), drip irrigation + straw mulching (MI) and control treatment (CK), and the effects of various watering and fertilization treatments on the growth and photosynthetic characteristics of Coffea arabica with the density of 4500 individuals per hectare were measured. The results showed that during one year's growth period, the coffee plants had two growth peaks, one was in May when the rainy season just begun, and the another was in August to September, the middle of rainy season. Higher fertilization promoted the relative height and length growth rates of the branches, but watering treatments hadn't significant effects on them. In dry season, watering significantly promoted the Pn, gs, Tr and WUE, while water status had no significant influence on the internal fluorescence features of PSII. In wet season, high-fertilized plants had a higher leaf nitrogen content and Pn than low-fertilized plants, and Pn was positively correlated with leaf nitrogen content. In both seasons, higher fertilization increased the WUE regardless of the watering treatments. At the same time, the high-fertilization treatment significantly alleviated diurnal photoinhibition, companying with a higher energy utilization through photochemistry and a higher energy dissipation through xanthophyll cycle, which appears that high-fertilized coffee plants have the mechanism to acclimate to strong light environment. All the results indicated that wet season is the optimum time for the photosynthesis and growth of C. arabica, and C. arabica needs a high fertilization investment and fine watering managements during its whole growth period. Among the three man-made watering treatments, MI was the best, M and I had the nearly same effects but the former was more practical than the latter.