34 research outputs found

    Different yellowing degrees and the industrial utilization of flue-cured tobacco leaves

    Get PDF
    Yellowing is a key stage in the curing of flue-cured tobacco (Nicotiana tobacum L.) as much of the chemical transformation occurs during this period. This study examined the effect of different yellowing degrees on the value of flue-cured tobacco leaves at the farm level for both processing and manufacturing. The study was conducted in the counties of Chuxiong, Dali, and Yuxi in Yunnan, China over two years. Yellowing treatments have been designed to have either a mild or a regular yellowing degree. Yield, value, appearance, suction property, smoking characteristics, and physical resistance to further processing were investigated to evaluate the effect of degree of yellowing on the industrial utilization of flue-cured tobacco leaves. The regular yellowing degree enhanced yield, value, and appearance compared to the mild yellowing degree, regardless of cultivar or location; however, physical resistance to further processing and the suction property of the mild yellowing degree treatment were better than with the regular yellowing degree regardless of cultivar or location. Furthermore, although the regular yellowing degree recorded higher smoking characteristic scores than the mild yellowing degree immediately after flue-curing, the scores of mild yellowing degree leaves could be further augmented by increasing intensity in the re-drying stage. The smoking characteristic score in the regular yellowing degree can only be increased by low intensity re-drying, and significantly decreased by mild and high intensity re-drying. Therefore, in terms of industrial utilization, mild yellowing is the better choice for flue-curing tobacco. This study also suggested that the current regular yellowing stage in Yunnan should be shortened to meet the demands of the traditional tobacco industry

    MiCroKit 3.0: an integrated database of midbody, centrosome and kinetochore

    Get PDF
    During cell division/mitosis, a specific subset of proteins is spatially and temporally assembled into protein super complexes in three distinct regions, i.e. centrosome/spindle pole, kinetochore/centromere and midbody/cleavage furrow/phragmoplast/bud neck, and modulates cell division process faithfully. Although many experimental efforts have been carried out to investigate the characteristics of these proteins, no integrated database was available. Here, we present the MiCroKit database (http://microkit.biocuckoo.org) of proteins that localize in midbody, centrosome and/or kinetochore. We collected into the MiCroKit database experimentally verified microkit proteins from the scientific literature that have unambiguous supportive evidence for subcellular localization under fluorescent microscope. The current version of MiCroKit 3.0 provides detailed information for 1489 microkit proteins from seven model organisms, including Saccharomyces cerevisiae, Schizasaccharomyces pombe, Caenorhabditis elegans, Drosophila melanogaster, Xenopus laevis, Mus musculus and Homo sapiens. Moreover, the orthologous information was provided for these microkit proteins, and could be a useful resource for further experimental identification. The online service of MiCroKit database was implemented in PHP + MySQL + JavaScript, while the local packages were developed in JAVA 1.5 (J2SE 5.0)

    Modeling phenological responses of Inner Mongolia grassland species to regional climate change

    No full text
    Plant phenology is an important indicator of ecosystem dynamics and services. However, little is understood of its responses to climate change, particularly in ecologically sensitive regions such as arid and semi-arid grasslands. In this study, we analyzed a long-term climate and plant phenology dataset of thirteen grassland species in the Inner Mongolia of China, collected during 1981ā€“2011 time period, to understand temporal patterns of plant phenology and then developed a simple chilling-adjusted physiological model to simulate phenological responses of each plant species to climate change. The results of regional climate analysis suggested that the minimum temperature was increasing at a greater rate than mean and maximum temperatures in the region and the climate variability had significant impacts on vegetation phenology. Chilling from an early stage in spring in general slowed down the phenological development in most plant species, although there were some inconsistencies among sites and years. Specifically, we found lower precipitation during green-up resulted in delayed flowering, which may attribute to plant self-adjustment strategy to respond changes in climate. These climate dependent phenologies were characterized by a simple physiological model. Scenario analysis suggested that by 2071ā€“2100 significant shifts in plant phenology are expected in Inner Mongolia, including as much as 6ā€“11 days earlier in green-up time and 8ā€“11 days shorter in growing season due to earlier senescence

    Productivity of strip intercropping systems in agro-pastoral ecotone

    No full text
    Strip intercropping system is not only a technique that achieves high productivity but also an important practice to protect winter and spring wind erosion in Agro-pastoral ecotone. Dry matter accumulation process and yield advantage of intercropping are vital indicators for exploration of intercropping performance and assessing the environmental benefit. This study is aiming to quantify crop growth, yield and land productivity in typical intercropping systems in agro-pastoral ecotone. An expolinear relationship between biomass growth and heat sum of above 0Ā°C temperature was fitted for different crops in the inter-and mono-cropping systems. The regression parameters were used to quantify the delay of crop growth in the intercropping. Land equivalent ratio (LER) was used to explain land productivity and over-yielding of the intercropping systems. The main results showed that sunflower/potato, oats/potato and oats/bean strip intercropping systems with wider width of strips (e.g. 2 m:2 m intercropping) significantly increased land productivity with yield land equivalent ratio (LER) of 1.12, 1.09 and 1.05, respectively, which means 5% to 12% of the land productivity increasing. Intercropping yield advantages were significantly higher in the wider strip intercropping systems than that with narrower ones (1 m:1 m intercropping), and had a less yearly variation. The harvest index (HI) of sunflower was significantly increased in intercropping, while that for other crops were significantly changed. A border row effect was clearly found in the oat based intercropping systems. The border rowers had a significantly higher yield compare to middle rows in the intercrops and sole oats. Strip intercropping decreased the maximum growth rate cm, while the relative growth rate rm stayed as the same as the monoculture. The growth delay of crops in the intercrops was quantified by using the parameter tb, which indicated the thermal time requirement at the time of reaching maximum canopy cover. The growth of five species in the intercropping systems, e.g. sunflower, potato, oats, faba bean and vetch, were delayed 117 to 387 degree days compared to that of monocultures, which resulted 8-26 d of growth delay when we took the daily average temperature (15Ā°C) into accounts. All in all, Strip intercropping systems not only have over-yielding effects and higher economic benefits, especially in intercropping systems with wider strips, but also reduce the agricultural risks in the agro-pastoral ecotone climatically and economically.</p

    Adjusting Sowing Dates Improved Potato Adaptation to Climate Change in Semiarid Region, China

    No full text
    This article examines how potato production can be improved by altering planting date in Chinaā€™s semiarid region, thus improving potato adaptation to climate change

    Structure of a CENP-Aā€“histone H4 heterodimer in complex with chaperone HJURP

    No full text
    In higher eukaryotes, the centromere is epigenetically specified by the histone H3 variant Centromere Protein-A (CENP-A). Deposition of CENP-A to the centromere requires histone chaperone HJURP (Holliday junction recognition protein). The crystal structure of an HJURPā€“CENP-Aā€“histone H4 complex shows that HJURP binds a CENP-Aā€“H4 heterodimer. The C-terminal Ī²-sheet domain of HJURP caps the DNA-binding region of the histone heterodimer, preventing it from spontaneous association with DNA. Our analysis also revealed a novel site in CENP-A that distinguishes it from histone H3 in its ability to bind HJURP. These findings provide key information for specific recognition of CENP-A and mechanistic insights into the process of centromeric chromatin assembly
    corecore