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Auxin is one of the major endogenous hormones that regulate the spike morphology in crops. In order to explore the auxin pathway genes involving spike type in wheat, the line SY95-71 with spindle spike and line CH7034 with compacted spike were selected to detect the endogenous auxin content in their young spikes. The results showed that the tryptophan content in SY95-71's young spikes was significantly higher than that in CH7034. RNA-seq results showed that four specific auxin-related GO items were enriched in SY95-71 young spikes within the high confidence interval (P<0.01), and the relative expression levels of Tryptophan Decarboxylase genes (responsible for transforming tryptophan into tryptamine) and Auxin Response Factor genes (ARFs) in SY95-71 were significantly higher than those in CH7034. Further analysis of two highly expressed ARF genes (TraesCS7A02G475600 and TraesCS7A02G475700) in SY95-71 revealed that they were a pair of tandem repeat genes located on the long arm of chromosome 7A and named TaARF23-A1 and TaARF23-A2 based on the IDs of ARF family member in wheat, respectively. The qRT-PCR results confirmed that the relative expression levels of TaARF23-A1 and TaARF23-A2 in SY95-71 young spikes were significantly higher than those in CH7034. The sequencing results showed that the exon of TaARF23-A had two SNPs and one InDel site between SY95-71 and CH7034. A molecular marker was developed based on the InDel site and then used to associated with the spike phenotypes of the recombinant inbred lines population derived by the cross of SY95-71 and CH7034 in six field environments. The results showed that TaARF23-A was significant correlation with spikelet number (P<0.0001), and its CH7034 allele increased by 1.67 spikelets compared with the SY95-71 allele. The results of this study provide the reference for the understanding of the development mechanism of spikelet and molecular marker for the improvement of ideal spike type in wheat. [ABSTRACT FROM AUTHOR]

This paper presents an improved version of the firefly algorithm (FA) by which a maximum power point (MPP) tracker was developed to track down the global maximum power point (GMPP) of a partially shaded photovoltaic module array (PVMA). As the first step, our team developed a high-voltage step-up converter where a coupled inductor was used to store the energy so that the duty cycle can be reduced so as to raise the voltage gain. The single-peaked P-V output characteristic curve of a PV array turns out to contain multiple peaks when the array is partially shaded. As a consequence, conventional MPP trackers occasionally track down a local maximum power point (LMPP), instead of the desired GMPP, and the output power of the array falls accordingly. Therefore, an improved version of the FA is proposed as a way to ensure that the GMPP can be tracked down in a more efficient way. Using the Matlab software, the MPP tracking performance of the proposed tracker was finally simulated in five scenarios. As it turned out, the proposed converter provided a high voltage gain at a relatively low duty cycle, and the improved version of the FA outperformed the original in terms of tracking time. [ABSTRACT FROM AUTHOR]

Flag leaf is the main photosynthetic organ in wheat. The chlorophyll content is not only the major photosynthetic pigment in flag leaf but also an important phenotypic indicator in crop breeding. Therefore, the identification of major loci/genes related to chlorophyll content in the flag leaf play an important role in breeding wheat varieties with higher grain yields and stability. In this study, we constructed a double haploid (DH) population from a cross of two cultivars with significant difference in chlorophyll content, and the chlorophyll contents of DH lines were detected under five environments. A total of 20 QTLs associated with chlorophyll content were detected using Wheat 90K single-nucleotide polymorphism (SNP) array, with contributions to phenotypic variation explained (PVE) from 4.10% to 27.16%. Three QTLs (Qchl.saw-2D.1, Qchl.saw-4D.2, and Qchl.saw-6A) were identified under multiple environmental conditions, in which Qchl.saw-2D.1 with the strongest genetic effect was different from previous studies and identified as a novel major QTL. Furthermore, Qchl.saw-2D.1 was validated by a tightly linked kompetitive allele specific PCR (KASP) marker in a recombinant inbred line (RIL) population containing the co-parent Jinmai 919. Those lines with the favorable allele of Qchl.saw-2D.1 revealed significantly higher chlorophyll content than other lines under multiple environments. Moreover, a total of 12 candidate genes controlling chlorophyll content were identified in the three QTL regions. Based on gene annotation, three genes were involved in the binding process of metal iron, such as magnesium. Five genes were regulated the structural composition of chloroplasts, and four genes were engaged in the regulation of electron transfer activities during the photosynthetic process. In conclusion, this study will broaden the understanding of the genetic mechanism and provide a molecular basis for the marker-assisted breeding (MAS) of chlorophyll content in the flag leaf of wheat. [ABSTRACT FROM AUTHOR]

A sonography image processing system for tumour segmentation is implemented by using the active contour model based on level set formulation. To achieve extraction of weak edges in speckle noisy images, the level set model called Edge Attraction Force on Chan and Vese model is developed. The cell competition algorithm is modified by adding the information of the cells' edges. Calculus of variation is taken to derive the evolution equation of the active contour. Experiments demonstrate that the boundaries of tumours extracted by the proposed active contour are more accurate for conquering the drawbacks coming from weak edges. Experiments demonstrate that the boundaries of tumors extracted by the proposed active contour are accurate and the results avoid the drawbacks of the weak edges. [ABSTRACT FROM AUTHOR]

The red stigmas of saffron are one of the most expensive spices in the world and serve as a traditional Chinese medicine. More saffron has been cultivated in China, and different drying technologies have been studied. However, a comprehensive and comparative analysis of different drying approaches has not been well studied. In this study, we compared electric oven and vacuum oven drying approaches on saffron. We found saffron was dried quicker under high vacuum drying mode with high temperature and the quicker drying rate provided, the more open microstructural interstices on the saffron surface. Both methods were best fit to Midilli and Kucuk model. Besides, the coloring, aroma and bitterness strength after drying showed the similar results. In sum, our data suggested the optimal drying temperature was 100 °C for 20 min for two evaluated methods, however considering the machine cost, the electric oven drying would be the first choice. [ABSTRACT FROM AUTHOR]