Aflibercept combined with triamcinolone acetonide in the treatment of diabetic macular edema: optical coherence tomography and optical coherence tomography angiography.

AIM: To analyze the relationship between optical coherence tomography (OCT) and OCT angiography (OCTA) imaging in patients with diabetic macular edema (DME) who are treated with a combination of aflibercept and triamcinolone acetonide (TA). METHODS: A total of 76 eyes newly diagnosed DME were included in this study. They were randomly assigned to receive either aflibercept or a combination of aflibercept and TA. Injections once a month for a total of three injections. Central macular thickness (CMT), number of hyperreflective foci (HRF), height of subretinal fluid (SRF), and area of foveal avascular zone (FAZ) were evaluated using OCT and OCTA at baseline and after each monthly treatment. RESULTS: Both groups showed improvement in best corrected visual acuity (BCVA) and reduction in macular edema after treatment, and the difference in BCVA between the two groups was statistically significant after each treatment (P<0.05). The difference in CMT between the two groups was statistically significant after the first two injections (P<0.01), but not after the third injection (P=0.875). The number of HRF (1mo: 7.41±8.25 vs 10.86±7.22, P=0.027; 2mo: 5.33±6.13 vs 9.12±8.61, P=0.034; 3mo: 3.58±3.00 vs 6.37±5.97, P=0.007) and height of SRF (1mo: 82.39±39.12 vs 105.77±42.26 µm, P=0.011; 2mo: 36.84±10.02 vs 83.59±37.78 µm, P<0.01; 3mo: 11.57±3.29 vs 45.43±12.60 µm, P<0.01) in combined group were statistically significant less than aflibercept group after each injection, while the area of FAZ showed no significant change before and after treatment in both groups. CONCLUSION: The combination therapy of aflibercept and TA shows more significant effects on DME eyes with decreased HRF and SRF. However, both aflibercept and combination therapy show no significant change in the area of FAZ.

PdmIRD: missense variants pathogenicity prediction for inherited retinal diseases in a disease-specific manner.

Accurate discrimination of pathogenic and nonpathogenic variation remains an enormous challenge in clinical genetic testing of inherited retinal diseases (IRDs) patients. Computational methods for predicting variant pathogenicity are the main solutions for this dilemma. The majority of the state-of-the-art variant pathogenicity prediction tools disregard the differences in characteristics among different genes and treat all types of mutations equally. Since missense variants are the most common type of variation in the coding region of the human genome, we developed a novel missense mutation pathogenicity prediction tool, named Prediction of Deleterious Missense Mutation for IRDs (PdmIRD) in this study. PdmIRD was tailored for IRDs-related genes and constructed with the conditional random forest model. Population frequencies and a newly available prediction tool were incorporated into PdmIRD to improve the performance of the model. The evaluation of PdmIRD demonstrated its superior performance over nonspecific tools (areas under the curves, 0.984 and 0.910) and an existing eye abnormalities-specific tool (areas under the curves, 0.975 and 0.891). We also demonstrated the submodel that used a smaller gene panel further slightly improved performance. Our study provides evidence that a disease-specific model can enhance the prediction of missense mutation pathogenicity, especially when new and important features are considered. Additionally, this study provides guidance for exploring the characteristics and functions of the mutated proteins in a greater number of Mendelian disorders.

High preseason temperature variability drives convergence of xylem phenology in the Northern Hemisphere conifers.

Wood growth is key to understanding the feedback of forest ecosystems to the ongoing climate warming. An increase in spatial synchrony (i.e., coincident changes in distant populations) of spring phenology is one of the most prominent climate responses of forest trees. However, whether temperature variability contributes to an increase in the spatial synchrony of spring phenology and its underlying mechanisms remains largely unknown. Here, we analyzed an extensive dataset of xylem phenology observations of 20 conifer species from 75 sites over the Northern Hemisphere. Along the gradient of increase in temperature variability in the 75 sites, we observed a convergence in the onset of cell enlargement roughly toward the 5th of June, with a convergence in the onset of cell wall thickening toward the summer solstice. The increase in rainfall since the 5th of June is favorable for cell division and expansion, and as the most hours of sunlight are received around the summer solstice, it allows the optimization of carbon assimilation for cell wall thickening. Hence, the convergences can be considered as the result of matching xylem phenological activities to favorable conditions in regions with high temperature variability. Yet, forest trees relying on such consistent seasonal cues for xylem growth could constrain their ability to respond to climate warming, with consequences for the potential growing season length and, ultimately, forest productivity and survival in the future.

Interguild fungal competition in litter and soil inversely modulate microbial necromass accumulation during Loess Plateau forest succession.

Microbial interactions determine ecosystem carbon (C) and nutrient cycling, yet it remains unclear how interguild fungal interactions modulate microbial residue contribution to soil C pools (SOC) during forest succession. Here, we present a region-wide investigation of the relative dominance of saprophytic versus symbiotic fungi in litter and soil compartments, exploring their linkages to soil microbial residue pools and potential drivers along a chronosequence of secondary Chinese pine (Pinus tabulaeformis) forests on the Loess Plateau. Despite minor changes in C and nitrogen (N) stocks in the litter or soil layers across successional stages, we found significantly lower soil phosphorus (P) stocks, higher ratios of soil C: N, soil N: P and soil C: P but lower ratios of litter C: N and litter C: P in old (>75 years) than young stands (<30 years). Pine stand development altered the saprotroph: symbiotroph ratios of fungal communities to favor the soil symbiotrophs versus the litter saprotrophs. The dominance of saprotrophs in litter is positively related to microbial necromass contribution to SOC, which is negatively related to the dominance of symbiotrophs in soils. Antagonistic interguild fungal competition in litter and soil layers, in conjunction with increased fungal but decreased bacterial necromass contribution to SOC, jointly contribute to unchanged total necromass contribution to SOC with stand development. The saprotroph: symbiotroph ratios in litter and soil layers are mainly driven by soil P stocks and stand parameters (e.g., stand age and slope), respectively, while substrate stoichiometries primarily regulate microbial necromass accumulation and fungal: bacterial necromass ratios. These results provide novel insights into how microbial interactions at local spatial scales modulate temporal changes in SOC pools, with management implications for mitigating regional land degradation.

VS-Cambium-Developer: A New Predictive Model of Cambium Functioning under the Influence of Environmental Factors.

Climate changes influence seasonal tree-ring formation. The result is a specific cell structure dependent on internal processes and external environmental factors. One way to investigate and analyze these relationships is to apply diverse simulation models of tree-ring growth. Here, we have proposed a new version of the VS-Cambium-Developer model (VS-CD model), which simulates the cambial activity process in conifers. The VS-CD model does not require the manual year-to-year calibration of parameters over a long-term cell production reconstruction or forecast. Instead, it estimates cell production and simulates the dynamics of radial cell development within the growing seasons. Thus, a new software based on R programming technology, able to efficiently adapt to the VS model online platform, has been developed. The model was tested on indirect observations of the cambium functioning in Larix sibirica trees from southern Siberia, namely on the measured annual cell production from 1963 to 2011. The VS-CD model proves to simulate cell production accurately. The results highlighted the efficiency of the presented model and contributed to filling the gap in the simulations of cambial activity, which is critical to predicting the potential impacts of changing environmental conditions on tree growth.

Mismatch between primary and secondary growth and its consequences on wood formation in Qinghai spruce.

The connections between the primary and secondary growth of trees allows better understanding of the dynamics of carbon sequestration in forest ecosystems. The relationship between primary and secondary growth of trees could change due to the diverging responses of meristems to climate warming. In this study, the bud phenology and radial growth dynamics of Qinghai spruce (Picea crassifolia) in arid and semi-arid areas of China in 2019 and 2020 were weekly monitored to analyze their response to different weather conditions and their links with carbon sink. Xylem anatomical traits (i.e. lumen radial diameter and cell wall thickness) were quantified along cell radial files after the end of xylem lignification to calculate the early-to-latewood transition date. Winter and early spring (January-March) were warmer in 2020 with a colder April compared with 2019. Precipitation in April-June was lower in 2020 than in 2019. In 2019, bud phenology occurred earlier, while the onset of xylem formation and the early-to-latewood transition date were delayed. The duration from the beginning of split bud and exposed shoot to the early-to-latewood transition date was positively correlated with the radial width of earlywood (accounting for ~80% of xylem width) and total xylem width. The longer duration of xylem cell division did not increase xylem cell production and radial width. Moreover, the duration from bud burst to the early-to-latewood transition date in 2020 was negatively linked with early phloem cell production as compared with 2019. Our findings suggest that warm conditions in winter and early spring promote the xylogenesis of Qinghai spruce, but might delay bud burst. However, the xylem width increments largely depend on the duration from bud burst to the start of latewood cell division rather than on the earlier xylogenesis and longer duration of xylem cell differentiation induced by warm conditions.

Precipitation regulates the responses of xylem phenology of two dominant tree species to temperature in arid and semi-arid forest of the southern Altai Mountains.

Arid and semi-arid forests are important carbon sinks, with implications for the global carbon balance. However, the impacts of climate warming on the growth of arid and semi-arid forest tree species and ecosystem carbon sink dynamics remain uncertain because the effects of the complex interactions between precipitation and temperature on xylem phenology are not clearly understood. Here, we monitored xylem formation over two years in two dominant tree species (Siberian larch, Larix sibirica Ledeb.; Siberian spruce, Picea obovata Ledeb.) along the arid and semi-arid southern Altai Mountains of Central Asia. We determined that temperature interaction with precipitation plays a key role in regulating xylem phenology of these two species, with differences between species. Under rising mean annual temperatures, the growth of L. sibirica advanced as the onset of xylem formation was not limited by early season water availability. However, the earlier cessation of cell enlargement, likely due to legacy effects, compensated for such advancement. In contrast, water stress constrained the advancement of xylem formation under rising temperatures in P. obovata. Nevertheless, water stress was seemingly relieved later in the growing season and consequently did not lead to the earlier cessation of xylem formation. Our results demonstrate that precipitation drives species-specific response to rising temperatures and thus is a key driver of growing season length and carbon sink dynamics in arid and semi-arid forests under climate warming. Integrating the effects of temperature and precipitation on xylem phenology in climate models may improve estimates of climate-carbon feedback in arid and semi-arid forests under future warming scenarios.

Application of Ceriporia lacerata HG2011 as biocontrol agent against multiple phytopathogenic fungi and oomycetes.

Overuse of fungicides to control crop diseases results in ecological damage, environmental pollution, and human health risks. Biocontrol is an increasingly popular alternative in plant disease management due to sustainability and environmental friendliness. Herein, antagonistic tests and greenhouse experiments were conducted to investigate the antagonism of a self-isolated white-rot fungus Ceriporia lacerata HG2011 against phytopathogens in vitro, the underlying mechanism exerted by this fungus, and disease control efficiency in the greenhouse. The results demonstrated that both soluble and volatile substances produced by this fungus suppressed the growth of all test phytopathogen fungi and oomycetes in vitro, with the inhibitory rates of 10.4-60.6% for soluble metabolites and 30.3-52.9% for volatiles. C. lacerata HG2011 could grow in and gradually spread on living phytopathogenic colonies, concurrently deformed and lysed pathogenic hyphae in dual culture, which were associated with the release of hydrolase (cellulose, chitinase, ß-glucanase, and protease) from this biocontrol fungus for the use of the pathogens as nutrient sources. The chitinolytic and cellulolytic production by C. lacerata HG2011 presents the specific response to the cell wall of pathogenic fungi and oomycetes, and ß-glucanase was triggered by carbon competition. Consequently, C. lacerata HG2011 successfully controlled eggplant stem blight and cucumber vine blight (control efficacy 67.9-70.9%) in the greenhouse experiments. C. lacerata HG2011 showed multiple antagonistic mechanisms against the phytopathogenic fungi and oomycetes concurrently. Our results provided information about a new potential use of this fungus as a biocontrol agent to control plant diseases in modern agriculture beyond medical purposes, wastewater treatment, and biofuel production.

A critical thermal transition driving spring phenology of Northern Hemisphere conifers.

Despite growing interest in predicting plant phenological shifts, advanced spring phenology by global climate change remains debated. Evidence documenting either small or large advancement of spring phenology to rising temperature over the spatio-temporal scales implies a potential existence of a thermal threshold in the responses of forests to global warming. We collected a unique data set of xylem cell-wall-thickening onset dates in 20 coniferous species covering a broad mean annual temperature (MAT) gradient (-3.05 to 22.9°C) across the Northern Hemisphere (latitudes 23°-66° N). Along the MAT gradient, we identified a threshold temperature (using segmented regression) of 4.9 ± 1.1°C, above which the response of xylem phenology to rising temperatures significantly decline. This threshold separates the Northern Hemisphere conifers into cold and warm thermal niches, with MAT and spring forcing being the primary drivers for the onset dates (estimated by linear and Bayesian mixed-effect models), respectively. The identified thermal threshold should be integrated into the Earth-System-Models for a better understanding of spring phenology in response to global warming and an improved prediction of global climate-carbon feedbacks.

Climate warming leads to advanced fruit development period of temperate woody species but divergent changes in its length.

Climate warming has significantly altered the phenology of plants in recent decades. However, in contrast to the widely reported warming-induced extension of vegetative growing season, the response of fruit development period (FDP) from flowering to fruiting remains largely unexplored, particularly for woody plants. Analyzing >560,000 in situ observations of both flowering and fruiting dates for six temperate woody species across 2958 European phenological observations sites during 1980-2013, we found that in all species both flowering and fruiting phenology, that is, the FDP, advanced with climate warming. However, the advancing rates of the two events were not necessarily equal for any given species, resulting in divergent changes in the length of FDP among species with climate warming. During 1980-2013, not only the temperature during FDP but also the forcing requirement for fruit development increased, both affecting the length of FDP. The shortened FDP was mainly due to elevated temperature, thus accelerating the accumulation of forcing, whereas the prolonged FDP was primarily caused by the substantial increase of the forcing requirement of fruiting, which could be fulfilled only in a longer time and thus slowed down the advance of fruiting. This study provides large-scale empirical evidence of warming-induced advances of FDP but divergent changes in its length in temperate woody species. Our findings demonstrate the contrasting reproductive phenological strategies among temperate woody species under the pressure of warming climate, contrary to the lengthening of vegetative growing season, which is by and largely similar with different woody species.

Environmental factors have a major effect in shaping the gene expression of Siberian larch in the Altai Mountains of China.

The differentiation of gene expression is an important link between genotype and phenotype and has important contributions to species adaptation and ecosystem evolution. As a major component of the world's forests, boreal forests play an important role in regulating the global climate, and the phenology of tree species has been and is undergoing changes during global warming. Here, to understand the impact of global warming on gene expression in boreal forest species, we used PacBio and Illumina sequencing methods to study the transcriptome of natural populations of Siberian larch (Larix sibirica Ledeb.) from the Altai Mountains in Xinjiang, China. We found that populations in this area had low genetic differentiation, but individuals were genetically clustered together when they had close geographic distance. Environmental factors, especially temperature, dominated differential gene expression of Siberian larch, while the contribution of genetic variation is relatively small. We speculate that Siberian larch adapts to changes in temperature and precipitation by altering its own gene expression. These results not only predict the tolerance of boreal forests to higher temperatures in the future, but also inform forest management strategies under global climate change.

Multi-slice spiral computed tomography in diagnosing unstable pelvic fractures in elderly and effect of less invasive stabilization.

BACKGROUND: Older people are more likely to experience pelvic fractures than younger people. Multi-slice spiral computed tomography (CT) uses three-dimensional (3D) reconstruction technology to generate 3D images that can clearly demonstrate the 3D space of fractures and detect fractures at a higher rate. AIM: To investigate the clinical value of multi-slice spiral CT 3D reconstruction in the diagnosis of unstable pelvic fractures in the elderly as well as the effect of less invasive stabilization. METHODS: A total of 86 patients with unstable pelvic fractures treated between March 2016 and March 2019 underwent femoral supracondylar bone traction before surgery. Pelvic radiography and multi-row spiral CT were performed successively once the patient's vital signs and hemodynamic indices were stable. Secondary processing of the original data was performed to obtain 3D reconstruction images and determine the vertical displacement of the pelvis. After basic or complete reduction, minimally invasive internal fixation using hollow lag screws was performed. The detection rates of fracture location and classification by X-ray and CT reconstruction were compared. Patients were divided into two groups according to the presence or absence of preoperative 3D reconstruction to compare postoperative reduction, wound healing time, fracture healing time, hospitalization time, visual analog scale (VAS) score, poor internal fixation, and functional recovery. RESULTS: The diagnostic coincidence rates of X-rays for pubic symphysis, ilium wing, sacroiliac periarticular, and sacral fractures were lower than those of CT reconstruction. The coincidence rate of CT reconstruction in the clinical classification of pelvic fractures was 100%, whereas 11 cases were misdiagnosed by X-ray; the total coincidence rate was 87.21%. The total excellent and good rates of postoperative reduction were significantly higher in the study group than in the control group (P < 0.05). The wound healing, fracture healing, and hospitalization times were significantly shorter in the study group than in the control group (P < 0.05). The VAS scores decreased in both groups postoperatively and were lower in the study group than in the control group (P < 0.05). The total incidence of poor postoperative internal fixation was significantly lower in the study group than in the control group (P < 0.05). The overall rate of postoperative functional recovery was significantly higher in the study group than in the control group (P < 0.05). CONCLUSION: Multi-slice spiral CT has high guiding significance for the diagnosis, classification, and treatment of unstable pelvic fractures in the elderly. Preoperative 3D reconstruction can effectively shorten the operation time and promote fracture healing, while minimally invasive internal fixation can effectively reduce pain and promote functional recovery of fracture sites, making it worthy of clinical application.

Effects of nitrogen addition and increased precipitation on xylem growth of Quercus acutissima Caruth. in central China.

Atmospheric nitrogen (N) deposition and increasing precipitation affect carbon sequestration in terrestrial ecosystems, but how these two concurrent global change variables affect xylem growth in trees (i.e., independently or interactively) remains unclear. We conducted novel experiments in central China to monitor the xylem growth in a dominant species (Quercus acutissima Caruth.) in response to N addition (CN), supplemental precipitation (CW) or both treatments (CNW), compared with untreated controls (C). Measurements were made at weekly intervals during 2014-15. We found that supplemental precipitation significantly enhanced xylem growth in the dry spring of 2015, indicating a time-varying effect of increased precipitation on intra-annual xylem growth. Elevated N had no significant effect on xylem increment, xylem growth rate, and lumen diameters and potential hydraulic conductivity (Ks) of earlywood vessels, but Ks with elevated N was significantly negatively related to xylem increment. The combination of additional N and supplemental precipitation suppressed the positive effect of supplemental precipitation on xylem increment in the dry spring of 2015. These findings indicated that xylem width was more responsive to supplemental precipitation than to increasing N in a dry early growing season; the positive effect of supplemental precipitation on xylem growth could be offset by elevated N resources. The negative interactive effect of N addition and supplemental precipitation also suggested that increasing N deposition and precipitation in the future might potentially affect carbon sequestration of Q. acutissima during the early growing season in central China. The effects of N addition and supplemental precipitation on tree growth are complex and might vary depending on the growth period and local climatic conditions. Therefore, future models of tree growth need to consider multiple-time scales and local climatic conditions when simulating and projecting global change.

Auxin concentration and xylem production of Pinus massoniana in a subtropical forest in south China.

Auxin is involved in various developmental processes of plants, including cell division in cambium and xylem differentiation. However, most studies linking auxin and xylem cell production are performed in environments with a strong seasonality (i.e., temperate and boreal climates). The temporal dynamics of auxin and cambial activity of subtropical trees remain basically unknown. In this study, we sampled four microcores weekly in three individuals of Chinese red pine (Pinus massoniana Lamb.) from February to December 2015-16 to compare xylem formation with auxin concentration in subtropical China. During the entire period of sampling, the number of cambial cells varied from 2 to 7, while the number of cells in the enlarging zone ranged from 1 to 4 and from 1 to 5 in the wall-thickening zone. In 2015, the average auxin concentration was 3.46 ng g-1, with 33 xylem cells being produced at the end of the year. In 2016, a lower auxin concentration (2.59 ng g-1) corresponded to a reduced annual xylem production (13.7 cells). No significant relationship between auxin concentration and number of xylem cells in differentiation was found at the weekly scale. Unlike in boreal and temperate forests, the lack of wood formation seasonality in subtropical forests makes it more difficult to reveal the relationship between auxin concentration and number of xylem cells in differentiation at the intra-annual scale. The frequent and repeated samplings might have reduced auxin concentration in the developing cambium and xylem, resulting in a lower xylem cell production.

A circular RNA, circUSP36, accelerates endothelial cell dysfunction in atherosclerosis by adsorbing miR-637 to enhance WNT4 expression.

Atherosclerosis is a fatal disorder that is fundamental to various cardiovascular diseases and severely threatens people's health worldwide. Several studies have demonstrated the role of circular RNAs (circRNAs) in the pathogenesis of atherosclerosis. circUSP36 acts as a key modulator in the progression of atherosclerosis, but the molecular mechanism underlying this role is as yet unclear. This study aimed to elucidate the mechanism by which circUSP36 exerts its function in an in vitro cell model of endothelial cell dysfunction, which is one of pathological features of atherosclerosis. The circRNA traits of circUSP36 were confirmed, and we observed high expression of circUSP36 in endothelial cells exposed to oxidized low-density lipoprotein (ox-LDL). Functional assays revealed that overexpression of circUSP36 suppressed proliferation and migration of ox-LDL-treated endothelial cells. In terms of its mechanism, circUSP36 adsorbed miR-637 by acting as an miRNA sponge. Moreover, enhanced expression of miR-637 abated the impact of circUSP36 on ox-LDL-treated endothelial cell dysregulation. Subsequently, the targeting relationship between miR-637 and WNT4 was predicted using bioinformatics tools and was confirmed via luciferase reporter and RNA pull-down assays. Notably, depletion of WNT4 rescued circUSP36-mediated inhibition of endothelial cell proliferation and migration. In conclusion, circUSP36 regulated WNT4 to aggravate endothelial cell injury caused by ox-LDL by competitively binding to miR-637; this finding indicates circUSP36 to be a promising biomarker for the diagnosis and therapy of atherosclerosis.

Photoperiod and temperature as dominant environmental drivers triggering secondary growth resumption in Northern Hemisphere conifers.

Wood formation consumes around 15% of the anthropogenic CO2 emissions per year and plays a critical role in long-term sequestration of carbon on Earth. However, the exogenous factors driving wood formation onset and the underlying cellular mechanisms are still poorly understood and quantified, and this hampers an effective assessment of terrestrial forest productivity and carbon budget under global warming. Here, we used an extensive collection of unique datasets of weekly xylem tissue formation (wood formation) from 21 coniferous species across the Northern Hemisphere (latitudes 23 to 67°N) to present a quantitative demonstration that the onset of wood formation in Northern Hemisphere conifers is primarily driven by photoperiod and mean annual temperature (MAT), and only secondarily by spring forcing, winter chilling, and moisture availability. Photoperiod interacts with MAT and plays the dominant role in regulating the onset of secondary meristem growth, contrary to its as-yet-unquantified role in affecting the springtime phenology of primary meristems. The unique relationships between exogenous factors and wood formation could help to predict how forest ecosystems respond and adapt to climate warming and could provide a better understanding of the feedback occurring between vegetation and climate that is mediated by phenology. Our study quantifies the role of major environmental drivers for incorporation into state-of-the-art Earth system models (ESMs), thereby providing an improved assessment of long-term and high-resolution observations of biogeochemical cycles across terrestrial biomes.

[Effect of different fertilization treatments on growth,secondary metabolites,and seed yield and quality of Perilla frutescens].

Perilla frutescens,an annual plant in Labiatae family,is grown throughout China and can be used for medicine purposes and as food additives. The present field experiment was carried out to study the effects of different fertilizer treatments on the concentrations and accumulations of antioxidant components,including flavonoids and polyphenols,growth,seed yields and qualities of this plant.The main aim of this study is to provide farmers some advice for improving the yields and qualities of P. frutescens in theory and practice.Five treatments were set up,including a no fertilizer control(CK),chemical fertilizers(CF),organic fertilizers(M),organic fertilizers plus chemical fertilizers at the rates of 1 ∶1 and 1 ∶3 in terms of nitrogen(50 M,25 M). Plant growth parameters were recorded and total flavonoids and polyphenols were determined in three key growth stages of P. frutescens. At the fast growth period,samples of roots,leaves,and stems were collected for determining a total of flavonoids and polyphenols as well as DPPH removal rate of ethanol extracts. Seed yields and qualities were also recorded at harvest. The results showed fertilization enhanced growth and seed yields although no significant difference was observed in growth and seed yields in inorganic-organic fertilizer treatments. The total flavonoids,polyphenols,and DPPH removal rate of ethanol extracts followed the sequence leaves>stems>roots,indicating synthesis of these metabolites in the leaves. DPPH removal rate showed a positive linear correlation with total flavonoid and polyphenol concentrations. In addition,organic-inorganic fertilization significantly increased the numbers of both effective panicles and paniclegrains. Fertilizer treatments had no effect on seed qualities of P. frutescens,while 50 M achieved the highest yield,which increased by 14. 73% compared to CF alone. In general,50 M increased antioxidant components,biomass,and seed yield of P. frutescens,meriting advocate in cultivation.

Responses of bud-break phenology to daily-asymmetric warming: daytime warming intensifies the advancement of bud break.

There is evidence that the ongoing climate change is happening through nighttime rather than daytime warming. How such a daily-asymmetric warming modifies plant phenology is still unclear. We investigated the effects of asymmetric warming on bud break by daily monitoring seedlings belonging to 26 black spruce [Picea mariana (Mill.) BSP.] and 15 balsam fir [Abies balsamea (L.) Mill.] provenances from the native range in Canada. Seedlings were subjected to either daytime or nighttime warming in three growth chambers at temperatures ranging between 10 and 24 °C. On average, a warming of 4 °C advanced the timings of bud break in both species by 2.4 days, with the later phases being more sensitive to the treatment. Bud break of both species responded more strongly to daytime warming, with the bud break occurred 1.2 and 3.2 days earlier under daytime than nighttime warming in black spruce and balsam fir, respectively. A marked ecotypic differentiation was only observed in black spruce that originated from provenances distributed broadly across Canada, with seedlings from the warmest provenance completing bud break 8.3 days later than those from the coldest one. However, no significant effect of provenance was observed for balsam fir, the narrowly distributed species. Overall, the above results suggest that a higher temporal resolution such as temperatures during daytime and nighttime, and higher spatial resolution should be taken into account to improve the accuracy of phenological model predictions under global change scenarios. Phenological models based on daily average temperature should take into account the diverging impacts of asymmetric warming on plant phenology. Our findings may indicate that the influence of warming on plant phenology may be less dramatic than expected.

Chilling and forcing temperatures interact to predict the onset of wood formation in Northern Hemisphere conifers.

The phenology of wood formation is a critical process to consider for predicting how trees from the temperate and boreal zones may react to climate change. Compared to leaf phenology, however, the determinism of wood phenology is still poorly known. Here, we compared for the first time three alternative ecophysiological model classes (threshold models, heat-sum models and chilling-influenced heat-sum models) and an empirical model in their ability to predict the starting date of xylem cell enlargement in spring, for four major Northern Hemisphere conifers (Larix decidua, Pinus sylvestris, Picea abies and Picea mariana). We fitted models with Bayesian inference to wood phenological data collected for 220 site-years over Europe and Canada. The chilling-influenced heat-sum model received most support for all the four studied species, predicting validation data with a 7.7-day error, which is within one day of the observed data resolution. We conclude that both chilling and forcing temperatures determine the onset of wood formation in Northern Hemisphere conifers. Importantly, the chilling-influenced heat-sum model showed virtually no spatial bias whichever the species, despite the large environmental gradients considered. This suggests that the spring onset of wood formation is far less affected by local adaptation than by environmentally driven plasticity. In a context of climate change, we therefore expect rising winter-spring temperature to exert ambivalent effects on the spring onset of wood formation, tending to hasten it through the accumulation of forcing temperature, but imposing a higher forcing temperature requirement through the lower accumulation of chilling.