Infl uence of altitude and tree class on climate-growth relationships in a larch plantation in subtropical China

Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest management.However,whether diff erences in the response of growth to climate at diff erent altitudes remains unclear.To answer this,264 trees of Larix kaempferi from 88 plots,representing diff erent altitudinal ranges(1000-2100 m)and tree classes were sampled and used to develop tree-ring chronologies.Tree-ring growth(TRG)was either positively(dominant)or negatively(intermediate and suppressed)correlated with climate in diff erent tree classes at diff erent altitudes.TRG was strongly correlated with growing season at low altitudes,but was less sensitive to climate at middle altitudes.It was mainly limited by precipitation and was highly sensitive to climate at low altitudes.Climate-growth relationships at high altitudes were opposite compared to those at low altitudes.TRG of dominant trees was more sensitive to climate change compared to intermediate and suppressed trees.Climate factors(annual temperatures;moisture,the number of frost-free days)had diff erent eff ects on tree-ring growth of diff erent tree classes along altitudinal gradients.It was concluded that the increase in summer temperatures decreased water availability,resulting in a signifi cant decline in growth rates after 2005 at lower altitudes.L.kaempferi is suitable for planting in middle altitudes and dominant trees were the best sampling choice for accurately assessing climate-growth relationships.

Altitude shape genetic and phenotypic variations in growth curve parameters of Larix kaempferi

To study the effects of geoclimatic variables of provenances on growth phenotypes and selected plus provenances,over 3000 trees of 22-year-old Larix kaempferi were evaluated from trials established in two climate zones for provenance selection and to explore the influence of climate variables on provenance performance.The material was replicated plantings of 84 open pollinated families from six provenances distributed in the mountains of central Japan.Provenance variation was observed in most age groups and the heritability of growth traits showed large differences.The phenotypic maximum value of height and diameter were significantly positive with altitude,and mean annual precipitation being important factors.Diameter at breast height growth was significantly negative with altitude and spring rainfall.The Ina provenance of relatively high altitudes,was well adapted to a variety of climates.Altitude might be the driving force for phenotypic and genetic variations and local adaptation.

Isolation,expression and single nucleotide polymorphisms(SNPs) analysis of LACCASE gene(LkLAC8) from Japanese larch(Larix kaempferi)

Nucleotide diversity(π) and linkage disequilibrium(LD) analysis based on SNP marker could provide a sound basis for choosing an association analysis method.Japanese larch(Larix kaempferi) is an important timber coniferous tree species for pulping and papermaking,but its high lignin content has significantly restricted it application potential.In this study,the LACCASE gene,that plays an important regulatory role for lignin biosynthesis,was selected as research target.The full-length c DNA and genomic sequences of the encoding Lk LAC8 gene were isolated from the LACCASE expressed sequence tags of the Japanese larch transcriptome database using the rapid amplification of c DNA ends-polymerase chain reaction(RACE-PCR).The c DNA was determined to be 1940 bp,with an open reading frame(ORF,1734 bp) that encoded a protein of 577 AA.This protein contains four highly specific Cu^(2+) binding sites and 11 glycosylation sites,thus belonging to the LACCASE family.The deduced protein sequence shared an 89% identity with the Pta LAC from Pinus taeda.A real-time PCR analysis showed that the Lk LAC8 transcript was expressed predominantly in mature xylem,with moderate levels in the immature xylem,cambium and mature leaves,the lowest in the roots.Lastly,the genomic sequences of Lk LAC8 in 40 individuals from six naturally distributed populations of Japanese larch were amplified,and a total of 201 SNPs(103 and 98 mutation types of transition and transversion,respectively) were detected;the frequency of the SNPs was 1/19 bp.Nucleotide diversity among the six populations ranged from 0.0034 to 0.0053,which suggested that there were no significant differences among the populations.The LD analysis showed that the LD level decayed rapidly within the increasing length of the Lk LAC8 gene.These results implied that LD mapping and association analysis based on candidate gene may be feasible for the marker-assisted breeding of new germplasms with low lignin in Japanese larch.

Genetic variation of height growth rhythm between clones of Larix kaempferi × L. gmelini based on logistic models

Fifty-three larch interspecific hybrid clones(Larix kaempferi × L.gmelini) and their parent clones were used for growth curve analysis of height variations.The growth curves of the 55 clones were 'S'-shaped and 36 exhibited similar curves as the male parent.The coefficients of the logistic models were higher than 0.943,indicating that our results were effective in the simulation of the growth curves.ANOVA analysis showed significant differences in height of different clones (P\0.01).Average date of maximum height growth was Day 173,and average duration of rapid growth lasted for 50 days.Annual average increase in height was 9.7cm d^(-1) and daily average increase was 0.2 cm.The ratio of GR to the total annual increase in height ranged from 51.2 to 68.8%,with the average being 59.8%.There was a positive correlation between k values and plant heights which benefited from the evaluation of early plant height.There was also a positive correlation between GR(growth stage),GD(plant height) and annual increase in height.These results are informative to the evaluation of the elite clone selection and provide a theoretical basis for breeding and management.

不同品系杜洛克后代商品猪胴体性状的比较分析

为研究不同品系杜洛克作为终端父本对其后代商品猪胴体性状的影响,选取214和108头分别由美系和加系杜洛克公猪配种、出生时间相近(±2 d)和体重相近(35±5 kg)的后代三元商品猪进行育肥饲养,结束饲养后开展屠宰试验,测定背膘厚度、眼肌厚度、瘦肉率和肋骨数。结果显示:加系杜洛克商品后代的背膘厚度、眼肌厚度显著(P<0.05)高于美系杜洛克后代商品猪;加系杜洛克后代商品猪的瘦肉率、肋骨数显著(P<0.05)低于美系杜洛克。同一品系不同性别间背膘厚度、眼肌厚度、瘦肉率均不显著(P>0.05),加系商品公猪肋骨数极显著低于母猪肋骨数(P<0.01)。结论:美系杜洛克后代商品猪的胴体性状优于加系杜洛克后代商品猪。

Comparative transcriptome analyses reveal candidate genes regulating wood quality in Japanese larch(Larix kaempferi)

We studied the molecular mechanism of the quality traits of wood formation in larch.We used the immature latewood cells of two Japanese larch(Larix kaempferi)clones with significant differences in density and in microfibrillar angle(MFA)as materials to analyze their gene expression profiles.A total of 1735 differentially expressed genes were detected in immature latewood cells of the two clones,among which,971 were up-regulated and 764 were down-regulated.Digital gene expression profiling analysis revealed that genes encoding transcription factor members NAC66 and R2R3-MYB4,microtubule-associated protein,actin-related protein,cell wall protein members,arabinogalactan protein,Fasciclin-like arabinogalactan protein and glycine-rich protein,and several cell-wall-synthesis genes affected wood density and MFA by regulating latewood formation at transcriptional level.Our study results represent a basis for selection of quality traits and genetic improvement of larch wood.

Optimization of Factors Influencing Adventitious Rooting in Hybrid Larch

Optimization of in vitro adventitious root induction contributes to the development of a large-scale production system of hybrid clone seedlings of larch(Larix spp.).We used orthogonal testing to investigate the factors that affect the rooting of hybrid larch shoots-activated carbon,vitamin B1,sucrose,glycine,glutamic acid(Glu),cysteine,pH,and induction time in the dark and indole-3-butyric acid(IBA).Variance analysis showed that the effects of sucrose concentration on rooting rate,survival rate,and average root number,pH on the average number of roots;and Glu on survival rate were all significant(p<0.05)when compared to the mock treatments.Among all of the 45 treatments,the highest rooting rate was 90%,the highest survival rate was 100%,and the highest average root number was 11.8.The theoretically optimal procedure of in vitro root induction of hybrid larch shoots is shoot induction on L9 modified medium(pH 6.7)containing 2 mg.L^(-1)naphthalene acetic acid,0.25 mg.L^(-1)IBA,1/3 macroelements,7.5 g.L^(-1)sucrose,and 5 mg.L^(-1)Glu for 8 days,and then root induction on L9 modified medium without auxin.

Adsorption of cytochrome c by succinic anhydride-modified peanut shells

A novel adsorbent based on peanut shells modified with glutaraldehyde and succinic anhydride was prepared. Factors affecting the adsorption capacity, such as the pH, temperature, adsorption time, initial cytochrome c (cyt c) concentration and NaCl ionic strength, were extensively investigated. The results showed that the maximum adsorption capacity of the modified peanut shells (MPSs) was 432.6 mg/g when 10 mL of cyt c solution was adsorbed by 20 mg of MPSs at pH 5.0 for 3 h. In contrast, the adsorption capacities of the unmodified peanut shells (PSs), alkaline peanut shells (APSs) and crosslinked peanut shells (CPSs) were only 100.6, 180.3, and 173.0 mg/g, respectively, 4.3-, 2.4-, and 2.5-fold lower, respectively, than that of the modified shells. The desorption rate reached 89.9% with 1.5 mol/L NaCNS as an eluent, because the electrostatic attraction between the positive charges of the protein and the negative charges of the MPSs was reduced when the ionic strength was increasing. The MPSs were used to separate and purify cytochrome c from pig myocardium. A purification of 13.5-fold in a single step with a total enzyme activity recovery of 74.0% was achieved.

两纠缠二能级原子与单模光场相互作用的纠缠动力学过程研究

在光原子相互作用系统中,考虑两二能级原子间的偶极–偶极相互作用对原子间纠缠动力学过程的影响。研究表明:原子间的偶极–偶极相互作用对量子纠缠(共生纠缠度)动力学振荡过程具有抑制作用,当偶极–偶极相互为零时,量子纠缠呈双周期振荡效果,当偶极–偶极相互作用增强时,振荡频率逐渐降低,当偶极–偶极相互作用远大于原子与库环境相互作用强度时,量子纠缠呈明显的余弦振荡,其振荡频率为2πΩ/ ( √6g) . 。

Insights into spin polarization regulated exciton dissociation and charge separation of C_(3)N_(4)for efficient hydrogen evolution and simultaneous benzylamine oxidation

The employment of spin polarization under an external magnetic field holds great potential for the improvements of photocatalytic performance.However,owing to the huge difference in dielectric properties between ferromagnetic oxide and polymers,the photogenerated excitons with spin states are often limited to the ferromagnetic oxide wells,which leads to unsatisfactory activity.In this paper,a single-atom Co-doped C_(3)N_(4)photocatalyst is successfully synthesized for photocatalytic water splitting and simultaneous oxidation of benzylamine.Under a tiny external magnetic field(24.5 mT),the hydrogen production rate could reach at 3979.0μmol·g^(-1)·h^(-1),which is about 340 times that of C_(3)N_(4).Experimental results and theoretical calculations indicate that the interaction of Co d and N p orbital changes the symmetry center of C_(3)N_(4),resulting in an increase in dielectric constant and spin polarization.Moreover,magnetic fields further promote parallel electron spin,and the increased number of charges with the parallel spin-down state is likely to dissociate under the action of an external magnetic field.On the other hand,the Co-N bond provides a huge built-in electric field and active site for strengthening the charge transfer and surface reaction.This work not only deepens the understanding of spin polarization,but also enriches methods to accelerate electron-hole separation.

Species richness loss after nutrient addition as affected by N:C ratios and phytohormone GA_(3)contents in an alpine meadow community

Aims From the light-competition hypothesis,competition for light is asymmetric and the observed increases in plant-size variability with increasingly denser canopies are primarily due to competition for light.Greater plant height provides pre-emptive access to light and produces increased height differences among species.The question is what produces these differences in plant height or height growth response among species in response to fertilization.Methods In 2009,a field experiment of N,P and N+P enrichments at three levels each was initiated in an alpine meadow on the northeast Qinghai-Tibet Plateau.Effects of fertilization on species richness,aboveground net primary production(ANPP),relative light intensity and plant height of different plant functional groups were determined.Festuca ovina(grass),Kobresia humilis(sedge),Oxytropis ochrocephala(legume),Taraxacum lugubre(rosette forb)and Geranium pylzowianum(upright forb)were selected as exemplars of each of the indicated functional groups.The N:C ratios in aboveground biomass,gibberellic acid(GA_(3))concentrations in leaves,plant heights and height relative growth rate(RGR)of these exemplar species were analyzed in detail.Important Findings Species richness of grasses significantly increased with increasing N+P levels.Species richness of legumes and upright forbs decreased after N and N+P additions.P addition had no significant effect on species richness.The effects of N+P addition on species richness and ANPP were consistently stronger than those of the single N or P fertilization.Reductions in species richness caused by nutrient addition paralleled the increases in ANPP and decreases in light intensity under the canopies,indicating indirect effect of nutrient addition on species richness via ANPP-induced light competition.The exemplar species that responded most positively to fertilization in height and RGR also displayed stronger increases in their GA_(3) content and N:C ratios.GA_(3) concentrations and N:C ratios were positively correlated with height RGR when the data were pooled for all species.The tallest and the fastest-growing grass,F.ovina,had the largest increase in N:C ratios and the highest leaf GA_(3) concentrations after nutrient addition.These results indicated that differential responses of GA_(3) concentrations and N:C ratios to fertilization were related to the inequality in plant heights among species.

Mating patterns and pollen dispersal in a Japanese larch(Larix kaempferi) clonal seed orchard： a case study

Pollination dynamics highly determines the genetic quality of seed orchard crops. However, there is less research about the effect of mating patterns on seed productivity of orchard crops. So far, clonal seed orchards have been producing genetically improved seedlings used for most Japanese larch(Larix kaempferi(Lamb.) Carr.) plantations in China. In the present study, a total of 17 highly variable simple sequence repeat(SSR) markers were used for genotyping a progeny trial population consisting of 647 open-pollinated progenies germinated from seeds which were collected from 63 maternal clones with 140 potential paternal clones in a Japanese larch clonal seed orchard in China. Paternity analysis was used in the present case study in order to evaluate the level of paternal gametic contribution, estimate pollen contamination and selfing rates, and investigate pollination patterns,pollen dispersal patterns and the impact of mating patterns on seed productivity of orchard crops. We observed 93.7% of the success rate of the parental assignment, unequal paternal gametic contribution(0–12.4%) with 6.3% of the progenies derived from pollen contamination or unsampled pollen donors, and absence of evidence for selfing. We also found that pollination rate highly depended on the distance between pollen donors and maternal parents, the majority of the identified crossing(65.7%)occurred between clones within a 150-m radius, and large variations in growth performance existed among the paternal halfsiblings. Progeny growth performance(diameter at breast(DBH) and height(HGT)) was measured at Age-20 in order to investigate the impact of mating patterns on timber production of orchard crops. As either the paternal or maternal, two clones(i.e., clones Z38 and Z62) were identified to have produced progenies with higher average stem volume breeding values than that of all of the progenies. Specifically, the genetic gains for volume were 3.53% for the two clones as paternal parents, and 8.26% as the maternal parents at Age-20. Thus, both elite clones were ideal candidates for the construction of next-generation clonal seed orchards due to their synchronous reproductive phenology with greater crossing rate and higher genetic gain. These results improved the pedigree information to provide solid evidence of mating patterns for future design and effective management of seed orchards and for the development of viable long-term breeding strategies for other coniferous species.

发展基于活细胞的FlexStation3高通量钙荧光方法及筛选TRPV3通道抑制剂(英文)

为了建立高通量筛选TRPV3通道调节剂的方法,本研究利用FlexStation3酶标仪,针对瞬时转染TRPV3通道的HEK293T细胞的密度、Cal-520染料的浓度及染料孵育时间进行了条件优化。结果显示,40 000个细胞/孔、5.0%的Cal-520染料浓度及1.5 h的染料孵育时间为最佳实验条件。应用该筛选方法,筛选并发现来源于睡莲科植物的有效成分甲基莲心碱(neferine)能够抑制TRPV3通道,该抑制作用经全细胞膜片钳实验证实并测得其IC_(50)为24.5±4.1μM(n=6)。对其它TRPV通道成员的选择性电生理学评价结果显示,甲基莲心碱对TRPV1和TRPV4通道无抑制作用。总之,实验数据显示,Flex Station3高通量钙荧光筛选可以用于发现TRPV3以及其他TRP通道的调节剂,筛选发现的天然产物甲基莲心碱可以作为TRPV3通道的工具药研究通道的药理学功能。

Age-related trends in genetic parameters for wood properties in Larix kaempferi clones and implications for early selection

Wood properties are important traits that determine quality of structural wood. With the aim of performing efficient early selection for wood properties we investigated genetic variation in 20 Larix kaempferi clones aged from 4 to 15 years for four quality traits: wood density, wall thickness to lumen area, microfibrillar angle(MFA) and modulus of elasticity(MOE). We observed that age-related trends in overall means varied for differen traits: MFA decreased with the age, while the others generally increased with the age. Phenotypic variance always showed significant differences from the age of 8 years onward, with CVG ranging from 4% to 25%. Also clonal repeatability increased steadily until 9 years old and then kept medium or higher intensity(0.4–0.8). After the age of 6, genetic correlations were generally higher than phenotypic correlations. Estimates of early selection efficiency suggested that the optimal selection age for wood density was at age 5–6 years, while it was 9–10 years for the other traits. In combination with previous results we proposed a comprehensive early selection strategy for larch clonal breeding that involved selection based on nursery rooting ability, phenology, growth traits, and wood properties.

Rapid pattern recognition of different types of sulphur-containing species as well as serum and bacteria discrimination using Au NCs-Cu2+ complexes

Discrimination of different types of sulfur-containing species not only helps us to deeply understand how sulfur affects cellular signaling,but also contribute to the early diagnosis of diseases.However,the current investigation about sulfur-containing species discrimination is mainly concentrated in biothiols,which is relatively limited for practical application.Toward circumventing this limitation,herein,a convenient sensor array consisting of three kinds of Au NCs-Cu2+ for simultaneous and rapid identification of different types of sulfur-containing species is reported.Based on the fingerprint-like fluorescence responses generated by competitive binding between Au NCs-Cu2+ and different sulfurcontaining species,not only ten different types of sulfur-containing species separately but also their binary or ternary randomly selected mixtures can be well discriminated even in human urine and serum samples.It is worth noting that it only takes 2 min to obtain the best response signals for sulfurcontaining species discrimination.Most importantly,serums from cancer patients(such as liver cancer and breast cancer) and healthy people as well as sulfur-oxidizing bacteria(SOB) and sulfur-free bacteria can be both effectively and rapidly identified within 2 min,respectively,making it a promising approach for point-of-care disease diagnostic.

粤港澳大湾区建设背景下的住房支持政策协同机制研究

粤港澳大湾区青年的安居乐业是大湾区深度融合发展的重要基础。当前面向港澳青年的住房支持政策散见于大湾区各地的人才住房和创业政策之中,尚未形成完整、独立的政策体系。政策制定中呈现政府单独发文较多,跨区域、跨部门政策协同较少等现象,政策执行中存在衔接不畅、交叉反复等问题,制约了面向港澳青年住房支持政策的整体效能。基于协同治理体制框架,本文从“领导力-驱动力-参与力”三个维度阐述了优化大湾区住房支持政策的协同机制。本文对于提升粤港澳大湾区青年的居住品质、提高粤港澳大湾区政府间合作水平、改善地方政府基本公共服务等具有政策启示。