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Stable and efficient grain production has been one of the most important challenges in modern agriculture in recent years. Agricultural planting structure has always been in the dynamic adjustment between "non-grain" and "grain-oriented" in China. The incentive effect of various subsidies on grain production has gradually weakened with market-oriented reforms, as well as the ever-increasing production and operation modes. The cost-effective public investment can be expected to serve as a policy tool for the long-term national food security. The construction of high-standard farmland is of great significance to optimize the agricultural planting structure in the various regions. In this study, a quasi-natural experiment was performed on China's high-standard farmland construction policy that was launched in 2010. China's provincial panel data was selected between 2005 and 2017. A continuous differences-in-differences model was constructed with the interaction of the highstandard farmland construction area. The core explanatory variable was utilized as the dummy variable for the duration of policy implementation. An empirical test was then carried out to determine the impact of the high-standard farmland construction policy on the "grain-oriented" evolution of the planting structure. Furthermore, the mechanism variables were introduced, such as the scale of farmland circulation, the increase of total agricultural machinery power, and the level of grain planting specialization. The inherent mechanism and transmission path were then revealed using a two-stage estimation model. The results showed: 1) The baseline regression analysis showed that the high-standard farmland construction policy posed a positive effect on the "grain-oriented" planting structure, which increased the proportion of grain crop planting by an average of 7.5%. Four methods were used for robustness testing, including placebo testing by changing the policy implementation time point, replacing core explanatory variables, considering the lag in policy implementation effects, and considering interfering policies such as grain subsidies, farmland rights confirmation, and agricultural insurance. 2) A joint hypothesis test was conducted on the coefficients before the policy implementation. The baseline model followed the parallel trend test. Furthermore, the dynamic impact analysis showed that there was an enhanced impact each year, as the scope and scale of highstandard farmland construction expanded. The cumulative effects were coupled with the ever-increasing soil fertility and agricultural infrastructure. 3) The impact mechanism analysis showed that the implementation of policies drove the evolution of planting structure towards "grain-oriented" via three pathways: the scale effect brought by land transfer, the improvement of grain planting revenue under mechanized operations, and the realization of external scale economy by upgrading the specialization level of grain planting. Therefore, high-standard farmland construction planning should be strictly implemented to actively adopt farmland engineering measures, such as field leveling, consolidation, and centralized contiguous management, in order to promote the transformation of low- and medium-yielding fields and comprehensive management of agricultural ecology. At the same time, the farmland transfer market can be expected to steadily develop for the high level of agricultural mechanization and agricultural socialization services, with emphasis on the specialization of grain planting. The policy impact of "storing grain on the ground" can also be realized in the construction of high-standard farmland. [ABSTRACT FROM AUTHOR]

Hydraulic architecture refers to the different morphological structures and water transport strategies acquired during the long-term evolution of plants. In this study, Chinese fir, an important commercial forest species in southern China, was examined, and hydraulic architecture characteristics with respect to ramification rate, canopy height, and ramification direction were studied. The results showed that changes in hydraulic architecture parameters of Chinese fir had pronounced rank effects; the hydraulic conductivity and leaf-specific conductivity were in the following order: main stem＞primary lateral branches＞secondary lateral branches; leaf-specific conductivity and Huber values were higher in primary than in secondary lateral branches. Hydraulic architecture parameters at different ramification rates were significantly affected by canopy height. Hydraulic conductivity and specific conductivity of the main stem decreased significantly with increasing canopy height, and the Huber value of the main stem increased significantly with increasing canopy height. Hydraulic conductivity and specific conductivity of primary and secondary lateral branches were the highest in the middle canopy, leaf-specific conductivity of the primary lateral branches decreased significantly with increasing canopy height, and leaf-specific conductivity of secondary lateral branches was the highest in the middle canopy. With regard to different ramification directions, hydraulic conductivity, specific conductivity, and leaf-specific conductivity of primary and secondary lateral branches were generally higher in the south and west directions than in the north and east directions. Correlation analyses showed that hydraulic conductivity at different ramification rates was significantly positively（P＜0.01） correlated with the total diameter, sapwood cross-sectional area, and leaf dry weight; specific conductivity of the main stem was significantly positively（P＜0.05） correlated with these factors, whereas the specific conductivity of primary and secondary lateral branches produced a negative correlation with them. Thus, the smaller the diameter of high-level branches of Chinese fir, the lower is the water transport ability. This hydraulic grade effect is beneficial to sacrificing inferior branches in order to maintain the water supply of superior branches when Chinese fir experience drought stress, which is an important adaption to drought acquired during long-term evolution. This study is of great significance for the breeding of drought-tolerant Chinese fir and sustainable plantation management [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】The bioinformatics characteristics of FtCOP1 gene（Fagopyrum tartaricum Gaertn） fromCOP1（Constitutive Photomorphogenic 1） of Fagopyrum tartaricum Gaertn and the expression pattern in anthocyanin biosynthesis of tartary buckwheat are studied, which provides a basis for further studying the molecular mechanism of the involvement of COP1 gene in anthocyanins biosynthesis, and provides reference for improving the quality of tartary buckwheat by using FtCOP1. 【Method】The COP1 gene of tartary buckwheat was cloned by PCR and analyzed by bioinformatics. The physicochemical properties, secondary and tertiary structure, prediction of subcellular localization, conserved domain and evolutionary relationship with COP1 protein of other species were analyzed. RT-qPCR was used to analyze the relationship between the gene and the expression level of anthocyanin biosynthesis structure genes and the anthocyanins content in tartary buckwheat under normal light and dark conditions. 【Result】The complete length of CDS of FtCOP1 gene was 2082 bp, which consisted of 13 exons and 12 introns, encodings 693 amino acids. The theoretical pI value was 6. 23 and the protein size was 75. 876 kD. It was supposed to be hydrophilic, located in the nucleus and contained a transmembrane helical domain without signal peptide. The main components of the secondary and tertiary structures were random coil and α helix. The COP1 protein of tartary buckwheat was most closely genetic related to the COP1 of quinoa. The COP1 protein has similar motif and conserved domains as that of other species, and the gene structure were also similar. The expression level of FtCOP1 in dark cultured sprouts was significantly higher than that in normal light cultured, and was negatively related to the expression of anthocyanin biosynthesis structural genes and anthocyanins accumulation. 【Conclusion】 COP1 proteins of tartary buckwheat and other species in plant evolution is conservative, and it is speculated that FtCOP1 may negatively regulate light-dependent anthocyanin biosynthesis. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a transcription factor first found in plants, WRKY plays an important role in plant growth and development. However, it has not been studied in Physcomitrella patens. By using the WRKY gene family data(accession number is PF03106) in Pfam database, this paper studied the basic information of WRKY in P. patens, which included physicochemical properties, protein secondary structure prediction, chromosome localization, exon and intron distribution and phylogenetic relationship. The results were as follows:(1)The WRKY gene family in P. patens consisted of 38 members which were divided into two major categories ─Ⅰ and Ⅱ, and the conserved domains of some WRKY genes had mutated.(2)The amino acid length of WRKY protein was 216-775 aa and the relative molecular mass was 24.5-82.8 kDa; Subcellular location showed that the proteins of WRKY gene family were distributed in the nucleus.(3)The secondary structure of WRKY protein was composed of four constituent elements: α-helix, extended strand, β-turn, and random coil; Except for PpWRKY11(α-helix dominated), the proportion of random coil was up to 70%.(4)The phylogenetic relationship with Arabidopsis showed that the number of the WRKY family members and the way of their revolution had changed in the process of plants' evolution, the number of exons of WRKY gene family members were 3-7.(5)The members of WRKY gene were randomly dispersed on 21 chromosomes without forming a gene cluster. This study analyzed the basic structure and properties of the WRKY gene family, and it was found that the WRKY gene family of Physcomitrella patens has evolutionary diversity and unique variability in conserved domains, laying the foundation for subsequent research. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objectives] The purpose of this study was to explore the function of BrbHLH49 gene in anthocyanin synthesis of purple tsai-tai. [Methods] Using purple tsai-tai as the material, the full-length BrbHLH49 was cloned by homology cloning method. The amino acid sequence alignment and evolution analysis were performed with other species. To study the subcellular localization of BrbHLH49 protein, the vector pEarlyGate101-BrbHLH49-YFP was constructed, and transformed into the agrobacterium, and then injected into tobacco leaves. Moreover, RT-qPCR was used to analyze the expression of BrbHLH49 gene in different tissues of purple tsai-tai and ‘CX-49’. And the relative expression levels of genes related to anthocyanin synthesis in wild-type and 35S:BrbHLH49-YFP transgenic Arabidopsis thaliana were analyzed by RT-qPCR. [Results] The open reading frame length of BrbHLH49 gene was 1 431 bp, encoding 476 amino acids. Subcellular localization results showed that BrbHLH49 protein was expressed in the nucleus. During plants evolution, the amino acid sequence of BrbHLH49 encoded had a close relationship with those of Brassica napus and Brassica oleracea var. oleracea. RT-qPCR results showed that the relative expression levels of BrbHLH49 in the stalks and leaves of purple tsai-tai were significantly higher than those of ‘CX-49’. Meanwhile, the expression levels of the genes related to anthocyanin synthesis in the transgenic A.thaliana plants were significantly higher than those of the wild-type. [Conclusions] BrbHLH49 was located in the nucleus. The BrbHLH49 gene was highly expressed in the stalks and leaves of purple tsai-tai. And overexpression of BrbHLH49 gene in A.thaliana could significantly increase the synthesis of anthocyanin. [ABSTRACT FROM AUTHOR]

[Objectives] The purpose of this paper was to identify ULT genes, and to analyze the sequence characteristics and expression patterns in several representative fleshy fruit crops, and to lay a foundation for studying the function of ULT genes in fleshy fruit development. [ Methods] The Bioinformatics tools were used to systematically and comprehensively identify ULT genes from 19 crops(including 13 fleshy fruit crops) at genome-wide level. The phylogenetic relationship, protein physicochemical prope1iy, protein conserved motif composition, exon/intron structure and promoter elements were analyzed. Public transcriptome data was used to analyze their expression patterns in the different tissues of different plant species. Specially, the expression of tomato SlULTJ in three non-ripening fruit :mutants was further analyzed. Real-time fluorescence quantitative PCR technology was used to analyze tomato SlULTJ expression in the different tissues and its response to the ethylene treatment. [ Results] Eighteen of 19 selected species contained one to three ULT genes, while Camelina sativa contained five ULT genes. The protein conserved motif composition and exon/intron structure were very similar among different species. The promoter regions of ULT genes contained a large number of light, hormone and abiotic stress responsive elements. ULT genes were expressed in the different tissues of different plant species, especially highly expressed in the fruit of fleshy fruit crops. The expression level of SlULTJ in tomato increased during fruit ripening, and could he induced by the ethylene treatment. Tomato SlULTJ expression was inhibited in three non-ripening fruit :mutants rin, cnr and nor. [Conclusions] ULT genes are relatively conserved in plant evolution. In addition to the function of ULT on roots, sterns, leaves and flowers, ULT genes also play roles in fleshy fruit development and ripening. In tomato, SlULTJ participates in the fruit ripening under the control of RIN, NOR, CNR genes and ethylene. [ABSTRACT FROM AUTHOR]

The evolution of different kinds of vessel molecules is always related to plant evolution. Ranunculaceae(Ranunculales)is a key family which links the basal angiosperm and the core-eudicots in the angiosperm phylogeny group system. Studies on the vessel perforation plates of this important family have great systematic significance, but few studies have been addressed till now. Here, the vessel elements and their perforation plates in the secondary xylem of Ranunculeae, including seven genera and eight species, were observed with the scanning electron microscope and the semithin section, in order to know the relationship betweenthe vessel with their environments in different species in Ranunculaceae of Ranunculeae. The results were as follows: Simple perforation plates were found in seven species, except for the Batrachium bungei; Scalariform perforation plates were found in four species, i.e. Callianthemum taipaicum, Adonis sutchuenensis, Ranunculus sceleratus and Halerpestes cymbalaria, but not for Ranunculus chinensis, Oxygraphis glacialis and Ceratocephalus orthoceras; Perforation plates of vessel elements of Adonis sutchuenensis were diverse, including simple perforation plate, scalariform perforation plate, reticulate perforation plate, gnetum type perforation plate, and scalariform-reticulate perforation plate; Simple perforation plate, scalariform perforation plate, and reticulate perforation plate were found in Halerpestes cymbalaria. In this study, we did not found vessel elements by dissociation the root and stem of Batrachium bungei. On the contrary, we found that there were annular vessels by semithin section. We also found that the side walls, and the pit membranes were unbroken or residual. The length diversities of those vessel elements of Ranunculeae were very high. There were significant differences in the average length of vessel elements in different species of Ranunculeae. At the same time, the differences were conspicious among different types of vessel elements even in the same species. We also discussed the adaptive significance of different types of vessel elements and the systematic position of Ranunculeae in the family Ranuculaceae. The results indicate that micro-structures of the vessel elements are also adapted to their growing environments. The vessel elements of Callianthemum taipaicum, Adonis sutchuenensis and Oxygraphis glacialis were related to their cold environments and those of Ceratocephalus orthoceras and Batrachium bungei were related to xerophytic and aquatic environment, respectively [ABSTRACT FROM AUTHOR]

Floral structure co-evolution with pollinators is a key factor of the success of evolution in flowering plants. In Annonaceae, pollination chamber is a characteristic feature of floral structure. Diversity of the flowers size, perianth whorls, the number of petals per whorl and the connecting pattern between petals, lead to annonaceous morphology of pollination chamber hightly diversity. The floral structures of 68 of total 107 genera in Annonaceae were reported to date. According to the closed degree of the pollination chamber during anthesis, pollination chambers of the 68 genera were classified into three types: open type, partially closed type and tightly closed type to research the evolution of pollination chambers in Annonaceae. The results were as follows:(1)24 genera existing the open type pollination chamber; 38 genera existing the partially closed type and 26 genera existing the tightly closed type. Approximately 17 genera contain two or three types of pollination chamber.(2)Different pollination chamber types had correspondent relationships with different pollinators. The bees and flies mainly pollinated for the species with open pollination chamber, as well as for the species that had partially closed and tightly closed chambers with larger space of chamber. The thrips mainly pollinated partially closed and tightly closed species.(3)Old-tropics and Neotropics were the distribution center of Anno-naceae. The species distributed in Old-tropics were very abundant but the types of chambers and pollinators were very unitary. The species distributed in Neotropics were fewer, but the types of chambers and pollinators were various. Previous studies have suggested that Africa is the origin center of Annonaceae. Open pollination chamber mainly distributed in African tropics, and commonly existed in earlier differentiate genera, which pollinated by small beetles. It was considered that open pollination chamber was the ancestral trait in Annonaceae; partially closed type distributed in African tropics, Asian tropics and American tropics; and tightly closed type mainly distributed in Asian tropics. Pollinators of the both had diversities. Therefore, the chambers of partially closed and tightly closed are more derived in Annonaceae. [ABSTRACT FROM AUTHOR]

Three-dimensional printing(3D printing)is a technique to manufacture objectives layer by layer with the powder metal or plastic adhesive materials based on the digital model. Due to its flexibility and accuracy, 3D printing plays an important role in military, aerospace and other manufacturing industries. Because of the unique advantages of 3D printing, the application of three-dimensional printing technology in plant reproductive ecology is promising, but is still at an initial stage. This paper summarizes the development of 3D printing technology and floral traits evolution in plant reproductive ecology, and reviews the latest applications of 3D printing technology in researches of plant productive ecology. We also discuss the potential application and direction in the future researches of plant reproductive ecology. [ABSTRACT FROM AUTHOR]

Mycorrhizal fungi are an important member of soil microorganisms, not only rich in genetic diversity and species diversity, but also in functional diversity, which mainly manifest in: 1) affecting the origin, evolution, and distribution of terrestrial plants, 2) promoting plant growth and development, 3) enhancing plant tolerance against environmental stress, 4) remedying polluted and degraded soils, 5) promoting agricultural, forestry, and animal husbandry production, and 6) maintaining ecological equilibrium and stabilizing ecosystem and its sustainable productivity. With the development of technique and research, more functions contributed by mycorrhizal fungi would be discovered. [ABSTRACT FROM AUTHOR]