Microtubules (MTs) are an essential component of the cytoskeleton in eukaryotic cells. Similar to other living organisms, for MTs, the organization and dynamics are critical for the normal growth and development of plants but are also responsible for environmental responses. Recently, Chinese scientists have made groundbreaking discoveries in illustrating the underlying mechanisms of MTs in precise regulating the dynamic organization of cortical arrays in plants.

In angiosperms, DELLA proteins (DELLAs) have emerged as the master transcriptional regulators responsible for repressing all aspects of gibberellin (GA)-dependent growth and development. Previous investigations have demonstrated that DELLAs are involved in almost all processes of plant development. The evidences indicate that DELLA ex- pressed in male reproductive organs, female reproductive organs and embryos in flowering plants and play a major role in diverse key events in the process of sexual reproduction of angiosperms. Here, we try to summarize the knowledge of DELLAs concerning the structural components, characteristics, expression and function in reproductive tissues during the process of plant sexual reproduction. The problems and perspectives are also discussed.

As a wide-spread stress adaption in plants, proline accumulation is thought to result from increased biosynthesis and decreased degradation. However, accumulating reports showed that proline transport also plays a role in stress-induced proline accumulation. In plants, several amino acid transporter protein families, such as AAPs, LHTs and ProTs, can transport proline. In this review, we summarize the expression pattern, function and expression regulation of these families in terms of proline transport, with an aim to provide some useful information on proline transport and accumulation research in plants.

Polychlorinated biphenyls (PCBs) pose serious harm to humans and the environment. PCBs have a hormesis effect, but the inner mechanism still remains unknown. In this paper, we used Populous tomentosa seedlings to investigate the effect of treatment with a PCB compound, Aroclor1254 (3 mg·L^-1), on the differentiation of adventitious roots, phytohormone content and the expression of P009g125900, P006g142600, and P002g222700 genes related to auxin expression as well as P005g2489 and P005g2376 genes related to cytokinin expression. Aroclor1254 could promote the differentiation of adventitious roots, shorten the initial root formation time of adventitious roots, and enhance the adventitious root number. During adventitious root differentiation, Aroclor1254 treatment alone had a similar effect as IBA alone on IAA/(ZR+dhZR) content and the gene expression of P006g142600, P002g222700, P009g125900, P005g2489, and P005g2376. To further verify the auxin effect of Aroclor1254, we used Zea mays and transgenic Arabidopsis thaliana modified with a DR5::GUS auxin reporter gene to investigate the growth of coleoptiles or the response pattern of DR5::GUS to Aroclor1254 exposure. Aroclor1254 at a suitable concentration range could induce DR5::GUS gene expression but had no effect on the growth of coleoptiles. Thus, Aroclor1254 has a biological effect of auxin and can positively affect the differentiation of adventitious roots of P. tomentosa seedlings; a phenomenon called hormesis, but is not a plant growth regulator.

This study aimed to reveal the characteristics of photosynthetic carbon assimilation and the change regulation in different internodes of Phyllostachys edulis stems during their rapid growth stage. We analyzed the photosynthetic pigment content and activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), phosphoenolpyruvate carboxylase (PEPC), NADP-malate dehydrogenase (NADP-MDH), NADP-malic enzyme (NADP-ME), phosphoenolpyruvate carboxykinase (PEPCK) and pyruvate, and orthophosphate dikinase (PPDK) in stems with different internodes. With increasing internode number of P. edulis stems, the content of chlorophyll a, chlorophyll b and carotenoid was all significantly reduced and the ratio of chlorophyll a/b showed a gradual upward trend. The activities of Rubisco, PEPC and PPDK in stems of P. edulis decreased significantly from the 1^st to the 10^th internode, then the rate of decrease gradually slowed down. The activities of NADP-ME declined significantly from the 1^st to the 13^th internode; after the 13^th internode, the enzyme activities tended to be stable. The activities of NADP-MDH decreased markedly from 1^st to the 25^th internode of stems. The ratio of PEPC/Rubisco increased gradually and the range was between 18.37 and 65.09, which was significantly larger than that in typical C₃ plants. The research showed that the assimilating capacity with carbon differed in different internodes, and the middle and lower stems grew relatively fast. The result of many C₄ enzymes and activities being significantly high provided strong evidence for the existence of a C₄ photosynthetic pathway in the stems of P. edulis.

Palynology is an important method to solve the micro-morphological differentiation of species in some complex groups. With the development of molecular phylogeny, combining the advantages of these two subjects may effectively solve the taxonomic issues in plants. Microlepia (Dennstaedtiaceae) is one of the most difficult genera in ferns in terms of taxonomy. In the present study, based on palynology matched with phylogeny and population sampling, we constructed the phylogeny of 280 samples by using both Maximum Likelihood and Bayesian methods with four plastid markers (rbcL, trnL-F, psbA-trnH and rps4). The spore morphology of 100 samples was observed and analyzed. Our results of comprehensive molecular phylogeny and palynology showed that (1) 15 species widely accepted based on plant morphology were strongly supported, and this complex group of Microlepia has been further clarified; (2) There may be crytic species in the populations of M. marginata; (3) M. yaoshanica Ching, M. lofoushanensis Ching, M. szechuanica Ching and M. subspeluncae Ching, treated as synonyms in previous studies, should be restored as independent species; (4) Many hybridization events of Microlepia were found; and (5) A complete infrageneric taxonomy of Microlepia was proposed.

Calculating the number of species on earth has always been an issue of extreme concern, and suspicious species are among the most important obstacles to solve. Presently, the type specimen is the only criteria for identifying the suspicious species but is difficult to observe and study effectively because of its special taxonomic position. Therefore, the mostly effective way is to search the original information for suspicious species in the type locality. As molecular biological method, DNA barcoding, has been widely used in species classification and identification and can be used to identify a suspicious species accurately and quickly. In this study, a suspicious species, Dryopteris yenpingensis, was used as an example. We used DNA barcode analysis with the molecular data for the material from the type locality and combined morphological traits to clarify the doubtful taxonomic status of D. yenpingensis. The results supported D. yenpingensis and D. liboensis as the same species, and D. liboensis should be treated as a synonym. This study provides a reference for clarifying the taxonomic status of other suspicious species.

Taking the Populus euphratica forest in the main stream of the Tarim River as the research object, the two sections of the Puman reservoir and Kanbaierwusitan were selected to analyze the characteristics of the radial growth of P. euphratica in the middle reaches of the upper reaches of the Tarim River. The runoff data from cross sections were selected and the response of the radial growth of P. euphratica to the dynamic change of runoff was studied by wavelet analysis and correlation analysis. In the Puman reservoir-Xinqiman section, the basal area increment (BAI) for P. euphratica and the runoff scale all oscillated in a 15-24 year time, and the year of the runoff concussion was earlier than the BAI oscillation year. In the Kanbaierwusitan-Yingbazha section, the BAI for P. euphratica and the runoff scale all oscillated in a 10-20 year time, and the year of the runoff concussion was earlier than the BAI oscillation year. In the main stream of the Tarim River, runoff was one of the main factors limiting the radial growth of P. euphratica. The BAI for P. euphratica was significantly correlated with runoff from November of the previous year to March of this year. In the midstream of the Tarim River, The BAI for P. euphratica was significantly correlated with the runoff from December of the previous year to March of this year. The sensitivity of P. euphratica BAI to runoff variation in different sections of Tarim River differed. In the upstream sampling area of the Tarim River, a reasonable runoff reached 1.334 0×10⁸ m³, and P. euphratica grew well. The range of optimal radial flow of P. euphratica growth in the sampling area was 0.380 3×10⁸ -1.205 6×10⁸ m³ in the middle reaches of the Tarim River.

The polar glycerolipidome of the model algal strain Chlamydomonas reinhardtii was analyzed qualitatively and quantitatively by using liquid chromatography coupled with mass spectrometry (LC-MS). Based on UPLC-ESI-Q-Trap/MS and UPLC-ESI-Orbitrap/MS², MS scanning, including neutral loss or precursor ion scanning, and MS/MS scanning were used to identify 109 molecular species possessing distinct mass-to-charge ratios and acyl chains. Targeted quantitative analyses based on external standards with UPLC-ESI-Q-Trap/MS in multiple reactions monitoring (MRM) mode was used to analyze individual molecular species. The results indicated that the glycerolipids of C. reinhardtii mainly included glycolipids (i.e., MGDG and DGDG) and betaine lipid, DGTS. In addition, analysis of fatty acyl constituents of all polar membrane lipids revealed that DGDG, SQDG, DGTS and PI acted as carriers for desaturation of C18 fatty acids. This study established a platform for characterizing the structure spectra and quantitative analysis with LC-MS techniques for C. reinhardtii, which provides a useful tool for studies of the biological function of polar membrane lipids and lipid metabolism in microalgae.

In this study, root, shoot, leaf, flower, fruit, peel and cambium tissue of Neolamarckia cadamba was sampled to analyze the expression of 43 candidate reference genes in 21 housekeeping gene families, such as ACT, CAC, CYP, and EF1α, by RT-qPCR. The software geNorm, NormFinder and BestKeeper were used to analyze expression stability of these candidate reference genes in the seven different tissues. geNorm analysis revealed that the stability of the UPL gene was the highest (M=0.443) and the stability of UBQ was the lowest (M=2.859). NormFinder analysis revealed that the stability of UPL was the highest (E=0.223), UBQ was the lowest (M=4.759). BestKeeper analysis revealed that the standard deviation of UPL (SD=0.513) was the lowest. These findings suggest that UPL has the highest stability, and UBQ has the lowest stability. UPL gene could be selected as an internal reference gene for analysis of gene expression among different tissues of N. cadamba.

We studied the effectiveness of different combinations of plant growth regulators and the light/dark condition on callus induction, proliferation and differentiation of bulb scales in Lilium martagon and established a high-frequency regeneration system. The optimal medium for callus induction was MS+0.2 mg?L^-1 TDZ+0.5 mg?L^-1 NAA, with embryogenic callus induced from 77.14% bulb scales. For callus proliferation, MS medium containing TDZ and NAA produced a browning appearance with the callus lost embryogenic ability quickly; therefore, 6-BA was applied instead of TDZ. Generation of buds from callus was reduced with 6-BA concentration increasing, which indicates that 6-BA plays a key role in keeping meristematic cells of callus from differentiating. The optimal medium for callus proliferation was MS+0.5 mg?L^-1 6-BA+0.1 mg?L^-1 NAA, with the proliferation coefficient 2.93. Dark treatment led to the highest callus induction rate, proliferation coefficient and number of buds/callus (77.14%, 2.93 and 5.43, respectively); callus showed good growth and the buds could grow roots and develop complete plants, which suggests that the dark condition is more appropriate for in vitro regeneration than the light condition. The rapid propagation system of L. martagon established in this study offers insights into germplasm protection, genetic transformation and application of L. martagon in China.

Leaf rolling is one of the important traits for breeding rice (Oryza sativa). Moderate leaf rolling plays a key role in plant photosynthesis, architecture and high yield. This paper reviews the research advances in rice leaf rolling, especially the cytological and molecular mechanisms of genes related to leaf rolling. These findings can facilitate a further understanding of the mechanisms and promote the use of the leaf rolling trait in rice breeding.

Tomato is one of the most widely cultivated and the most popular vegetable crops. It is also an important model plant of Solanaceae. The development of tomato fruit can be divided into early fruit development and fruit ripening, but fruit morphological structure and size are mainly determined by the early stage of fruit development. This review focuses on the early development of tomato fruit, including the molecular mechanism of plant hormones, cell cycle, epigenetics, and source-sink metabolism, to understand the basic biological problems of plant growth and development, as well as promoting the application of basic theoretical research results in production.