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Indole acetic acid (IAA) was believed to be an important regulator in xylem formation in conifers. However, few studies have been done on the endogenous amount of IAA in cambial region tissues in sugi (Cryptomeria japonica) trees. In this study, we report the IAA amounts in the lower and upper trunk of mature sugi cultivars (Kumotoshi, Yaichi and Obiaka) in September, and the effects of growth traits on the IAA amounts. The effect of height position (lower or upper trunk) on IAA amounts was found to be larger than that of genetic variation (Kumotoshi, Yaichi or Obiaka) by two-way ANOVA. There was no significant interaction effect (genetic variation × height position). The IAA amounts of all trees varied from 3 to 42 ng/cm2 at the lower trunk and 9 to 47 ng/cm2 at the upper trunk. Crown length and distance from crown base had significant positive and negative effects on IAA amounts in the trunk of sugi cultivars, respectively. Distance from crown base had a larger effect on IAA amounts than crown length. In Yaichi, taller trees had larger IAA amounts at both the lower and upper trunk.  相似文献   
65.
Trematodes of the genus Dicrocoelium are one of the most common parasites in ruminant animals; however, their life cycles in Japan are unclear. To find the sporocysts of D. chinensis in the natural field, we sampled 269 land snails (14 species) at a location with high level infection of sika deer in Gifu Prefecture, Honshu Island, Japan in autumn between 2017 and 2019. During the sampling period, we found mother sporocysts in the hepatopancreas of Aegista vulgivaga and Cyclophorus herklotsi. DNA barcoding based on the sequences of cytochrome c oxidase subunit 1 showed that the sporocysts from A. vulgivaga belonged to D. chinensis, indicating that this snail has potential as the first intermediate host of D. chinensis at this location.  相似文献   
66.
The mammalian forelimb is adapted to different functions including postural, locomotor, feeding, exploratory, grooming and defence. Comparative studies on morphology of the mammalian scapula have been performed in an attempt to establish the functional differences in the use of the forelimb. In this study, a total of 102 scapulae collected from 66 species of animals, representatives of all major taxa from rodents, sirenians, marsupials, pilosa, cetaceans, carnivores, ungulates, primates and apes, were analysed. Parameters measured included scapular length, width, position, thickness, area, angles and index. Structures included supraspinous and infraspinous fossae, scapular spine, glenoid cavity, acromium and coracoid processes. Images were taken using computed tomographic (CT) scanning technology (CT‐Aquarium, Toshiba and micro CT‐LaTheta, Hotachi, Japan), and measurement values were acquired and processed using Avizo computer software and CanvasTM 11 ACD systems. Statistical analysis was performed using Microsoft Excel 2013. Results obtained showed that there were differences in morphological characteristics of scapula between mammals with arboreal locomotion and living in forest and mountainous areas and those with leaping and terrestrial locomotion living in open habitat or savannah. Differences were seen in the ratio of maximum length and maximum width, the orientation of scapular spine and the horizontal length of acromion and coracoid processes. The cause for the statistical grouping of the animals and the way the scapular shape covaries with habitat and to the type of locomotion and speed are discussed in detail.  相似文献   
67.
Tripitaka Koreana is a collection of over 80,000 Buddhist texts carved on wooden blocks. In this study, we investigated whether six hardwood species used as blocks could be recognized by image recognition. An image data set comprising stereograms in transverse section was acquired at 10×?magnification. After auto-rotation, cropping, and filtering processes, the data set was analyzed by an image recognition system, which comprised a gray-level co-occurrence matrix method for feature extraction and a weighted neighbor distance algorithm for classification. The estimated accuracy obtained by leave-one-out cross-validation was up to 100% after optimizing the pretreatments and parameters, thereby indicating that the proposed system may be useful for the non-destructive analysis of all wooden carvings. We also examined the specific anatomical features represented by textures in the images. Many of the texture features were apparently related to the density of vessels, and others were associated with the ray intervals. However, some anatomical features that are helpful for visual inspection were ignored by the proposed system despite its perfect accuracy. In addition to the high analytical accuracy of this system, a deeper understanding of the relationships between the calculated and actual features is essential for the further development of automated recognition.  相似文献   
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探讨了新时代数字农业政策性金融服务体系的建设和推进,以促进经济高质量发展。研究指出,建设该体系对于将发展红利通过金融手段普及给广大人民群众至关重要。此外,本文还探讨了数字农业政策性金融服务与乡村振兴、城镇化建设之间的关联,强调了提高服务质量和效率的策略。在保障服务质量方面,本文提出了建立透明严格的监管制度的必要性,以应对金融风险。最后,为推进地区间数字农业政策性金融服务的融合交流,促进金融服务与经济发展的协调,呼吁加强区域合作和支持中西部地区的发展,为新时代数字农业政策性金融服务体系的发展提供参考。  相似文献   
69.
Some intergeneric hybrids produced by the crosses among several colchicaceous ornamentals, Gloriosa superba ??Lutea?? (2n = 2x = 22), G. ??Marron Gold?? (2n = 4x = 44), G. ??Verschild?? (2n = 7x = 77), Littonia modesta Hook. (2n = 2x = 22), and Sandersonia aurantiaca Hook. (2n = 2x = 24), were subjected to genomic in situ hybridization (GISH) analysis in order to clarify their genome constitutions. Chromosome preparation was made from root tip cells of L. modesta × G. superba ??Lutea??, L. modesta × S. aurantiaca, S. aurantiaca × G. superba ??Lutea??, L. modesta × G. ??Marron Gold??, S. aurantiaca × G. ??Marron Gold?? and G. ??Verschild?? × S. aurantiaca. Total DNA of one parent was labeled with digoxigenin or biotin and used as probe, and chromosomes were counterstained with 4??-6-diamidono-2-phenylindole (DAPI). For all the nine intergeneric hybrids, chromosomes from each parent could be clearly distinguished by GISH analysis. Thus GISH analysis is a powerful tool for identifying the genome constitution of intergeneric hybrids in colchicaceous ornamentals. The results obtained by GISH analysis study may be important for further progress in breeding of colchicaceous ornamentals.  相似文献   
70.
An experiment was conducted to identify the main nitrogenous compound transported in the xylem sap of soybean plants nodulated with Rhizobium fredii. Soybean (Glycine max L. Merr.) cultivars, wild type Bragg (nod+, fix+) and its nitrate tolerant, hypernodulating mutant ntsll16 (nod++, fix+) were used for this experiment. These soybean plants were inoculated with a slowgrowing rhizobium, Bradyrhizobium japonicum USDAllO or fast-growing rhizobia consisting of a mixture of R. fredii USDA191, USDA193, and USDA-194 and grown in a phytotron under natural light and controlled temperature conditions. Xylem sap was collected from Bragg and ntsll16 plants at the flowering and pod elongation stages. Acetylene reduction activity per plant or per nodule weight was not different between soybean lines and inoculums. The composition of the nitrogenous compounds in the xylem sap was compared between the symbionts, with B. japonicum and R. fredii. At the flowering stage, ureide-N and amide-N accounted for 53 to 70% and 20 to 27% respectively of the total N in the sap collected from the plants inoculated either with B. japonicum or R. fredii. At the pod elongation stage, ureide-N and amide-N accounted for 74 to 85%, and 7 to 19% of total sap N. With the growth of the soybean plants, the ratio of ureide-N in the xylem sap increased. These results suggest that in the case of wild soybean and the hypernodulating mutant line nodulated by R. fredii, ureide is transported as the main nitrogenous compound of fixed nitrogen in the xylem sap in the same way as in plants nodulated with B. japonicum.  相似文献   
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