Importance of oxygen-containing functionalities and pore structures of biochar in catalyzing pyrolysis of homologous poplar

Biochar and bio-oil are produced simultaneously in one pyrolysis process,and they inevitably contact and may interact,influencing the composition of bio-oil and modifying the structure of biochar.In this sense,biochar is an inherent catalyst for pyrolysis.In this study,in order to investigate the influence of functionalities and pore structures of biochar on its capability for catalyzing the conversion of homologous volatiles in bio-oil,three char catalysts(600C,800C,and 800AC)produced via pyrolysis of poplar wood at 600 or 800℃or activated at 800℃,were used for catalyzing pyrolysis of homologous poplar wood at 600℃,respectively.The results indicated that the 600C catalyst was more active than 800C and 800AC for catalyzing cracking of volatiles to form more gas(yield increase by 40.2%)and aromatization of volatiles to form more light or heavy phenolics,due to its abundant oxygen-containing functionalities acting as active sites.The developed pores of the 800AC showed no such catalytic effect but could trap some volatiles and allow their further conversion via sufficient aromatization.Nevertheless,the interaction with the volatiles consumed oxygen on 600C(decrease by 50%),enhancing the aromatic degree and increasing thermal stability.The dominance of deposition of carbonaceous material of a very aromatic nature over 800C and 800AC resulted in net weight gain and blocked micropores but formed additional macropores.The in situ diffuse reflectance infrared Fourier transform spectroscopy characterization of the catalytic pyrolysis indicated superior activity of 600C for removal of -OH,while conversion of the intermediates bearing C=O was enhanced over all the char catalysts.

The glutamate receptor gene GLR3.3:A bridge of calciummediated root development in poplar

Poplar is one of the fastest-growing temperate trees in the world and is widely used in ornamental horticulture for shade.The root is essential for tree growth and development and its utilization potential is huge.Calcium(Ca),as a signaling molecule,is involved in the regulation of plant root development.However,the detailed underlying regulatory mechanism is elusive.In this study,we analyzed the morphological and transcriptomic variations of 84K poplar(Populus alba×P.glandulosa)in response to different calcium concentrations and found that low Ca^(2+)(1 mmol·L^(-1))promoted lateral root development,while deficiency(0.1 mmol·L^(-1)Ca^(2+))inhibited lateral root development.Co-expression analysis showed that Ca^(2+)channel glutamate receptors(GLRs)were present in various modules with significance for root development.Two GLR paralogous genes,PagGLR3.3a and Pag GLR3.3b,were mainly expressed in roots and up-regulated under Ca^(2+)deficiency.The CRISPR/Cas9-mediated signal gene(crispr-PagGLR3.3a,PagGLR3.3b)and double gene(crispr-PagGLR3.3ab)mutants presented more and longer lateral roots.Anatomical analysis showed that crispr-PagGLR3.3ab plants had more xylem cells and promoted the development of secondary vascular tissues.Further transcriptomic analysis suggested that knockout of PagGLR3.3a and PagGLR3.3b led to the up-regulation of several genes related to protein phosphorylation,auxin efflux,lignin and hemicellulose biosynthesis as well as transcriptional regulation,which might contribute to lateral root growth.This study not only provides novel insight into how the Ca^(2+)channels mediated root growth and development in trees,but also provides a directive breeding of new poplar species for biofuel and bioenergy production.

Biobased Furfurylated Poplar Wood for Flame-Retardant Modification with Boric Acid and Ammonium Dihydrogen Phosphate

Furfurylated wood exhibits excellent dimensional stability and corrosion resistance,making it a promising material for constructing buildings,but it is highly flammable.Herein,flame-retardant furfurylated poplar wood was produced via a two-step process utilizing boric acid(BA)and ammonium dihydrogen phosphate(ADP)as flame-retardant components,and biomass-derived furfuryl alcohol(FA)as a modifier.The acidity of BA and ADP allowed them to catalyze the polymerization of FA,which formed a cross-linked network that immobilized BA and ADP inside the wood.The addition of BA/ADP substantially delayed the time to ignition from 10 to 385 s and reduced the total heat release and total smoke release by 58.75%and 77.31%,respectively.Analysis of the pyrolysis process showed that the decomposition products of BA and ADP protected the underlying furfurylated wood and diluted combustible gases.This method significantly improved the fire retardancy and smokeless properties of furfurylated wood,providing promising prospects for its application as an engineering material.

Studies of Transgenic Hybrid Poplar 741 Carrying Two Insect-resistant Genes

Partially modified Bt Cry1Ac gene and the arrowhead proteinase inhibitor (API) gene were used to construct a plant transformation vector pBtiA and this construct was transferred into the genome of the hybrid poplar 741 [ Populus alba L.×( P. davidiana Dode+ P. simonii Carr.)× P. tomentosa Carr.] by Agrobacterium _ mediated transformation. Ten kanamycin resistant plants have been regenerated. Upon insect bioassay using Clostera anachoreta (Fabricius), three of the examined plants were demonstrated to be highly resistant to the testing insects. The mortality of insect larvae on one plant was higher than 90% in 6 days after infestation and the growth of the survival larvae were seriously inhibited. Results of PCR and Southern blot analysis indicated that both Bt Cry1Ac gene and API gene were integrated as a single copy into the genomes of these three plants when Cry1Ac gene fragment was used as the probe. Protein dot blot immunoassay and ELISA analysis revealed that at least the Cry1Ac protein was produced in these three transgenic plants and the expression levels were estimated to be approximately 0.015% of the leaf total soluble protein. This is the first report on insect resistant transgenic hybrid poplar 741 that expresses two insecticidal protein genes.

Analysis of Codon Usage Between Different Poplar Species

Codon usage is the selective and nonrandom use of synonymous codons to encode amino acids in genes for proteins. The analysis of codon usage may improve the understanding of cocion preferences between different species and allow to rebuild the codons of exogenous genes to increase the expression efficiency of exogenous genes, Here, codon DNA sequence （CDS） of four poplar species, including Populus tremuloides Michx., P. tomentosa Carr., P. deltoides Marsh., and P. trichocarpa Torr. ＆ Gray., is used to analyze the relative frequency of synonymous codon （RFSC）. High-frequency codons are selected by high-frequency （HF） codon analysis. The results indicate that the codon usage is common for all four poplar species and the codon preference is quite similar among the four poplar species. However, CCT encoding for Pro, and ACT coding for Thr are the preferred codons in P. tremuloides and P. tomentosa, whereas CCA coding for Pro, and ACA coding for Thr are preferred in P. deltoides and P. trichocarpa The codons such as TGC coding for Cys, TTC coding for Phe, and AAG coding for Lys, are preferred in the poplar species except P trichocarpa. GAG coding for Glu is preferred only in P deltoides, while the other three poplar species prefer to use GAA. The commonness of preferred codon allows exogenous gene designed by the preferred cocion of one of the different poplar species to be used in other poplar species.

Effect of N Fertilization on Yield, N Absorption and Utilization of Two Species of Super High-Yielding Summer Maize

[Objective] The aim was to study on effects of N fertilizer on yield, N absorption and utilization of different cultivars of super high-yielding summer maize, in order to provide reference for reasonable N fertilization in accordance with different cultivars. [Method] Field experiment was conducted to study on effects of different N fertilizers on yield, N absorption and use efficiency of Zhengdan 958 and Xundan 20, in order to learn the effect differences at different N fertilizer levels. [Result] After N was applied, yields of the two summer maize increased significantly. Zhengdan 958 achieved the highest in yield and proceeds at 12 051.18 kg/hm2 and 1 722.40 yuan/hm2, respectively in low N level. In contrast, Xundan 20 achieved the highest at 13 166.00 kg/hm2 and 1 343.92 yuan/hm2 in the above two aspects in high N level. Compared with Zhengdan 958, Xundan 20 increased by 9.90%, 5.20% and 12.00% in N levels of 0, 240, and 450 kg/hm2, respectively. When N fertilizers were applied, protein yield of Xundan 20 was significantly higher than that of Zhengdan 958, so that higher N fertilizers contributed higher protein yield for Xundan 20. In high N level, N efficiency, N-fertilizer utilization and partial productivity of Xundan 20 were significantly higher than that of Zhengdan 958. [Conclusion] Lower N-fertilizer was suitable for Zhengdan 958 and Xundan 20 would get a good harvest if more N-fertilizers were applied. The results provided references for reasonable N fertilization.

Cloning of cDNA Encoding COMT from Chinese White Poplar ( Populus tomentosa ), Sequence Analysis and Specific Expression

The cDNA fragment encoding caffeic acid 3_O_methyltransferase (COMT) in Chinese white poplar ( Populus tomentosa Carr.) was isolated and cloned by RT_PCR technique. The size of the cDNA fragment is 1 080 bp, which almost covers the whole cDNA_encoding region. Authors’ cDNA fragment in P. tomentosa shares 98.7% homology with the reported corresponding cDNA in the P. tremuloids at nucleotide level, 99.4% homology at amino acid level, respectively. The analysis of Northern dot hybridization showed that COMT is expressed specifically in the developing secondary xylem of stem during the season of xylem differentiation, which means the linkage between the gene expression for a monolignol biosynthetic enzyme and seasonal regulation of xylem development in woody plant.

Variation of microfibril angle and its correlation to wood properties in poplars

The microfibril angle of seven poplar clones was determined by using X-ray diffraction technique. Microfibril angle, wood basic density, fiber length, fiber width and cellulose content were assessed for every growth ring at breast height for all sample trees. Significant variation in microfibril angle was observed among growth rings. Mean microfibril angle (MFA) at breast height varied from 7.8?to 28?between growth rings with cambial age and showed a consistent pith-to-bark trend of decline an-gles. Analysis of variance also indicated that there were significant differences in wood basic density, fiber length, fiber width and cellulose content between the growth rings, which had an increasing tendency from pith to bark. Correlations between MFA and examined wood properties were predominantly large and significant negative (?0.01), and the coefficients were -0.660 for cellulose content, -0.586 for fiber length, -0.516 for fiber width and -0.450 for wood basic density, respectively. Regression analysis with linear and curve estimation indicated that a quadratic function showed the largest R2 and the least standard error for describing the relationships between microfibril angle and measured wood properties, and the correlation coefficients were over -0.45 (n=125). The results from this study suggested that microfibril angle would be a good characteristic for improvement in the future breeding program of poplars.

Effects of two kinds of transgenic poplar on protective enzymes system in the midgut of larvae of American white moth

The leaves of Bt (Bacillus thuringiensis) transgenic poplar (Populus nigra L.) and CpTI (Cowpea trypsin inhibitor) transgenic poplar ((P. tomentosa×P. bolleana)×P. Tomentosa) were taken to feed the 4th-5th-instar larvae of American white moth (Hyphantria cunea (Drury)) for determination of the activities of the protective enzyme system inside larvae’s body. The physiological and biochemical effects of the transgenic poplars on the larvae were studied. The results showed that the two kinds of transgenic poplars had similar effects on the protective enzyme system in the midgut of larvae. The activities of superoxide dismutase, catalase, and peroxidase in midgut of the larvae increased gradually, reached the highest value at a certain time, and then decreased suddenly. For the larvae that were fed with the leaves of Bt transgenic poplar, the peak value of superoxide dismutase and catalase presented at the time of 24-h feeding, while the peak of peroxidase took place at the time of 12-h feeding. The activities of these protective enzymes for the larvae that were fed with leaves of CpTI transgenic poplar peaked 12 h later than that of those fed with leaves of Bt transgenic poplar. The comparison of activities of the protective enzymes was also carried out between the larvae with different levels of intoxication. It was found that the activities of protective enzyme of the seriously intoxicant larvae were higher than that of the lightly intoxicant larvae. This difference was more obvious in the group treated with CpTI transgenic poplar.

Status and Advances of Molecular Genetic Improvement of Poplar Species in China

Poplars are among the most important deciduous tree species in China. China is replete with natural resources of poplars. Poplars have a number of good characteristics, including fast growth rate, high yield, many uses, easiness of tissue culture and small gene group that make them well suited as a model system for the application of genetic engineering in forest trees. In the last decade, much progress has been made in genetic improvement of poplar species in China. Modern biotechnology is an important tool for genetic improvement in forest trees, and its applications to genetic improvement in poplars, which covers genetic transformation, gene expression, construction of genetic linkage map, QTLs (quantitative trait loci) identification and molecular assisted selection are reviewed in this paper. At the same time, the existing problems and outlook about the application of modern biotechnology to genetic improvement in forest trees are also discussed.

Evaluation of soil nutrient status in poplar forest soil by soil nutrient systematic approach

A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in laboratory through collection soil samples of study site. Ten treatments of application different fertilizers were designed such as CK, optimum treatment (N, P, K, Zn), N(P, K, Zn), P(N, K, Zn), K(N, P, Zn), +Mg(N, P, K, Zn, Mg), Zn (N,P,K), +2P(N, 2P, K, Zn), +2K(N, P, 2K, Zn), and 2N+2P+2K(2N, 2P, 2K, Zn) for field experiment to test the effect on tree height, diameter (DBH) growth, and dry weight of poplar. The results showed that there was no significant difference in tree heights between treatments with different fertilizers, diameter growth of poplar trees in treatments of lack of N and Zn was significantly slower than that of trees in optimum treatment, and dry weight of poplar dropped significantly for treatment of CK as well as treatments without application N and Zn. It is concluded that N and Zn were main limiting factor for poplar growth. Results from laboratory analysis and field experiment were uniform per-fectly, which proved that SNSA was reliable in evaluating soil nutrient status of poplar plantation.

Effect of Continuous Cropping on Leaf Nutrient and Growth of Different Species of Poplar Plantation

[Objective]The paper was to study the effect of continuous cropping on leaf nutrient and growth of different species of poplar plantation.[Method] The tree height,diameter at breast height（DBH）,volume of different generations and species of poplar plantation in poplar production area in northern Jiangsu Province,as well as TN,TP and TK content in their leaves were determined through field investigation and indoor experiment.[Result] With the increasing generation,the changes of TN,TP and TK content in the leaves of different ages of two varieties of forest stand were also different.However,with the increasing tree ages,TN,TP and TK contents in leaves showed decrease trend.With the increasing generation,the changes of tree height of I-69 and I-72 poplar showed the similar trend.The effect of increasing generation on tree height of 7-year-old and 10-year-old poplar was relatively stable,showing decrease trend from generation to generation.The tree height of 4-year-old poplar first increased and then decreased with the increasing generation.The changes of DBH along with different generations were basically consistent with the changes of tree height.With the increasing cultivation generations,the volume of 7-year-old and 10-year-old poplar decreased with significant difference.[Conclusion ] The result provided basis for rational fertilization and management of poplar plantation,improvement of productivity of poplar plantation,and achievement of sustainable management of plantation.

Effects of Ratio of Row Spacing to Intrarow Spacing on Yield and Top Three Leaves of Super High-yielding Early and Late Rice

Using a split plot design, super high-yielding early rice ＆quot;Zhongjiazao 17＆quot;and ＆quot;Ganxin 203＆quot; and super high-yielding late rice ＆quot;Ganxin 688＆quot; and ＆quot;Wufengy-ouT025＆quot; were taken as materials with planting density the same at 312 000 hil s/hm2, to explore the effects of RS/IS （Ratio of row spacing to intrarow row spacing） on yield, top three leaves morphological features and its relationship of them in 2011 and 2012. The results showed that, whether early or late rice, biomass, accumula-tion and apparent utilizing rate of nitrogen were lower in RS/IS5.0 （40.0 cm ＆#215;8.0 cm） treatment, but yield of rice was higher in RS/IS2.0 （25.0 cm ＆#215;12.8 cm） treatment;grain numbers per spike of rice was more in RS/IS2.8 （30.0 cm＆#215;10.7 cm） treatment, and thousand-grain weight of rice was higher in RS/IS1.3 （20.0 cm＆#215;16.0 cm） treat-ment. For 4 varieties of early or late rice aforementioned, basal angle, opening an-gle and leaf area of 2nd leaf from top were larger in RS/IS5.0 treatment, and basal angle and opening angle were smal er in RS/IS2.0 treatment and leaf area smal er in RS/IS1.3 treatment.

Regional epidemic laws of poplar Ice Nucleation Active bacterial canker

Through the methods of correlation analysis and main factor analysis, the relationship between the poplar INA bacte-rial canker and circumstances was analyzed and 9 main factors for affecting the disease were selected. Based on the compre-hensive analysis of main factors and induced factors, the standard for risk grades of this disease was promoted and northeast region of China was divided into 4 districts with different risk grades: seriously occurring district, commonly occurring district, occasionally occurring district, and un-occurring district. Nonlinear regression analysis for six model curves showed that the Richard growth model was suitable for describing the temporal dynamics of poplar INA bacterial canker. By stepwise variable selection method, the multi-variable linear regression forecasting equation was set up to predict the next year抯 disease index, and the GM (1,1) model was also set up by grey method to submit middle or long period forecast.

Structure Parameters and Physiological Indices Research of High-quality and High-yield Apple Orchards

In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of apple tree and community, and some physiological indices in fields and by room measurements. The results showed that tree height of high-quality orchard was in the range of 260 to 290 cm, branch angle in 70°-75°, and orchard coverage rate in 75%-94%, and the connec-tion rates between rows and trees were lower. Furthermore, the total branches of mature orchard reached 1.04 ×106 per hm2, while the young orchard was 8.79 ×105 per hm2; the leaves were thick and chlorophyl content was high, with SPAD value at 58.22. Additional y, the photosynthesis of the orchard was strong, and net photo-synthetic rate was 17.48-21.8 μmolCO2/（m2·s）. The proportions of lateral shoot of bearing part were 81% and 75% respectively.

Studies on adaptability of Populus bolleana and other Poplar trees in northwest Shanxi Province

Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana, P. ( eurameri cana and P. simonii, which were planted in loess hilly land in northwest Shanxi Province, were tested under different planting densities and site conditions. A randomized block design and three times repetition were adopted in the test. Bas ed on the test results in arid and cold area of the northwest Shanxi, the hybrid poplar trees taking Populus cathaysna as their female parent could be selected for afforestation, such as P. popularis and P. opera, and the growing space of s ingle plant should be larger than 20 m2. P. bolleana as an introduced tree speci es grows well in this area, but its growth is likely affected by ground water co ndition. On the site with relatively abundant soil water, P. bolleana usually su ffer from frost crack at its trunk base. As a result, P. bolleara is suited to p lanting in the site where is short of soil water. P. x euramericana is not suita ble for large-scale afforestation, especially in arid slopes and ridges of loess hilly land .

Relationship between trophic component of different poplar strains and occurrence of Saperda poplnea

An experimental area of poplar was established in Songyuan of Jilin Province in 1999 for testing the resistance of different poplar stains to Saperda poplnea. Incidence of S. poplnea on ten poplar strains were investigated, and the main trophic component of branches of these poplar trees were measured and analyzed in April 2001. The results showed that there existed significant difference in population size of S. poplnea on different poplar strains, and the branches of these poplar strains have significant difference in nutrient component and content of amino acids. The population size of this pest had a significantly positive correlation with dissolvable total sugar and water content but had no significant correlation with content of total nitrogen and protein nitrogen.

Field test of new poplar clone in Shangdong Province

Poplar is one of the dominant tree species for the establishment of fast growing plantations in Shandong Province. Eighteen poplar clones belonging to Populus aigeiros section were introduced from Italy, Turkey and domestic regions. Populus deltoides cv. 慙ux?I-69/55 (I-69), which was widely used in Shandong Province, China, was taken as control clone (I-69). Following a randomized complete block design, seedling test and controlled afforestation trials were carried out at Juxian County, Caoxian County and Laiyang City. The results showed that the poplar clone (Populus ?euramericana cv. ?02/74?, namely 102/74, performed well both in terms of adaptability and growth rate. The mean height of 13.9 m (H), diameter at breast height of 18.0 cm (DBH) and volume growth of 0.1445 m3 (V) were 2.2 %, 21.6% and 52.9 % higher than those of I-69 (CK), respectively, at the age of 5 years at three experimental sites. Moreover, the clone can be propagated easily and showed high resistance to poplar disease, pest as well as salinity and had longer growing period. Furthermore, wood basic density and fiber length of new poplar clone (102/74) were as same as I-69 (CK). It was concluded that the selected clone (102/74) was ideal for the estab-lishment of fast-growing poplar plantations, especially for the pulpwood plantations in Shandong Province.

Simplified High-yielding Cultivation Technology of Rice

[Objective] The aim was to select simplified high-yielding cultivation technology of rice. [Method] The research explored three methods of farmland prepara- tion, transplanting, and fertilization including shallow rotary tillage and deep ploughing, mechanical transplanting and hand transplanting, controlled-release fertilizer and quantitative fertilization in order to investigate effects of different treatment groups on rice characteristics, economic characteristics, as well as labor saving, yield increasing and profit improving. [Result] Rice increased by 596.4-809.55 kg/hm2, labor saving reached 120-135 per hm2, and profit improved in the range from 5 521.39 to 8 727.48 yuan/hm2 in the treatment groups by combinations of shallow rotary tillage, mechanical transplanting, and controlled-release fertilizer, of shallow rotary tillage, mechanical transplanting, and quantitative fertilization, and of deep ploughing, mechanical transplanting, and controlled release fertilizer. [Conclusion] The three models are of promising prospects in production.

High-yield Characteristics of Summer Sowing Soybean Varieties

[Objective] This study aimed to investigate the characteristics of high-yield soybean varieties.[Method] The agronomic traits of six high-yield soybean varieties and other 57 summer sowing ones were investigated from 2007 to 2010.[Result] The higher-yield summer sowing soybean varieties should have higher plants （R=0.551 6＊）,more effective pods （R=0.739 7＊）,more seeds per pod （R=0.318 9）,more flowers per plant （＞130）,higher pod setting rate （＞52％）,smaller ratio of aborted pods （＜40％）,longer tap roots （more than 20 cm） and lateral roots （more than 15 cm）,shorter bottom nodes （the length of six bottom nodes should be less than 25 cm）,lower center of gravity of the plant （＜40 cm）,greater stem dry weight,higher dry matter transformation rate and continuously increasing seed weight in late seed filling stage.The ideal growth stage model for summer sowing soybean was that the durations between adjacent stages of sowing,seedling emergence,flowering,seed setting and maturity stage were 5,29-33,29-33,32-36 d,respectively.[Conclusion] This pattern could not only satisfy the ecological conditions for double cropping system,but also balance the full development of vegetative and reproductive growth,promote the yield formation of summer sowing soybean.