Search Results (4)

Fruit shape is an important quality and yield trait of pear, and the fruit shape of ‘Laiyang Cili’ presents a spindle shape which seriously affects its commercial value. Calyx excision treatment could change the fruit shape, while the underlying genes and their regulatory mechanism remain poorly understood. In this study, we constructed RNA-seq libraries of pear treated with calyx excision to explore underlying regulatory mechanisms. At the early stage of the calyx excision treatment, the numbers of differentially expressed genes (DEGs) between each comparison group were relatively high and gradually decreased along with fruit development. The expression pattern of the DEGs ranked in the top 30 of the six groups had obvious divergence, and DEGs were mainly distributed in the “after calyx excision treatment (0 days)” (AC0d) and AC2d groups. The DEGs were mainly enriched in plant hormone signal transduction and plant defense response. We identified 17 candidate genes related to fruit shape and tested their expression patterns along with fruit development. Among them, nine candidate genes expression trends were consistent with fragments per kilobase of exon model per million mapped fragment (FPKM) values, including MYB62, outer envelope pore protein 62 (OEP62), auxin response factor 3 (ARF3), auxin-responsive protein 50 (SAUR50), protein phosphatase 2C 51 (PP2C 51), major allergen Pyr c 1 (PYRC1), aquaporin TIP1-3 (TIP1-3), transcription factor TGA4 (TGA4) and auxin-responsive protein 17 (IAA17). And then, weighted gene co-expression network analysis (WGCNA) analysis revealed that the OVATE family protein (OFP) and SUN domain-containing protein (SUN) were divided into the MEblue model, which had a positive correlation with calyx excision treatment, and the expression trend of LOC103960706 (OFP8) appeared cohesive with FPKM values. Pbr014104.1 and Pbr016952.1, which were the ortholog genes of LOC103960706, were further identified from the pear genome, and were found to be highly expressed in pear fruit through RT-PCR analysis. Taken together, the key stage determining the development of fruit shape was in the early stage after calyx excision treatment, and fruit shape regulation and development were co-regulated by multiple genes. Full article

The Lower Cretaceous Laiyang Group on Lingshan Island contains typical gas source and clastic reservoir rocks. The densification mechanism of clastic rock and its diagenetic connection have not been systematically studied, which significantly increases the risk associated with hydrocarbon exploration in eastern China. A comprehensive study was conducted on core samples obtained from the Scientific Drilling Borehole LK-1, utilizing core data in conjunction with a range of techniques, including microscopic observation, X-ray diffraction, physical property measurements, and low-temperature nitrogen adsorption. The results indicate that the sandstones are primarily composed of feldspathic litharenite, exhibiting a poorly to moderately sorted texture and a fine-to-medium grain size. The reservoir quality is quite poor, characterized by extremely low porosity and permeability. The reservoir space of tight sandstones is constituted by three main types of pores: residual primary pores, secondary dissolution pores, and intercrystalline pores. Tight sandstone reservoirs experienced notable diagenetic alteration during burial, with calcite, dolomite, quartz, and clay cements identified as the primary diagenetic minerals. Intense compaction and carbonate cementation are the principal mechanisms contributing to the densification of sandstones. Pore-filling clay minerals subdivide macropores into numerous micropores, significantly reducing reservoir permeability. The migration of dissolution products out of the system is a difficult process, which hinders the effectiveness of mineral dissolution in enhancing overall reservoir quality. This study may provide a valuable reference for the effective exploration of Lower Cretaceous clastic reservoirs in eastern Shandong. Full article

The Ri-Qing-Wei basin is located in the central Sulu Orogeny on the eastern side of the Tanlu fault zone in eastern Shandong province. To the north, the Jiaonan uplift separates it from the Jiaolai basin, where drilling in the lower Cretaceous sedimentary rock of the Laiyang group has indicated good oil and gas reserves. Drilling in the Ri-Qing-Wei basin, in contrast, is in the preliminary exploration stage. Lingke 1, the only scientific well, is on Lingshan Island on the basin boundary, and it encountered a large set of source rocks 700 m thick. The two basins were comprehensively compared and analyzed based on comprehensive fieldwork, drilling, core data, seismic profiling, sedimentary filling sequence, tectonic evolution history, basin burial history, geothermal history, and geochemical characteristics of the source rocks. The results showed three things: (1) from the late Jurassic to the early Cretaceous (the Laiyang period), subduction of the paleo-Pacific plate under the Eurasian plate delaminated the lithospheric mantle of the Sulu Orogeny, thus forming a series of passive continental rift basins. Of these, the Ri-Qing-Wei is central and the Jiaolai is its branch. After the active rift stage in the Qingshan period and the depression stage in the Wangshi period, the burial depth of the source rocks in the Ri-Qing-Wei basin was up to 6000 m, while the maximum burial depth in the Jiaolai basin was about 3000 m. The paleogeotemperature of both basins exceeded 125 °C, indicating that the source rocks were very mature. (2) A comprehensive comparison of their geochemical characteristics—organic matter abundance, type, and maturity—showed that both basins have oil-generating potential. It is worth noting that the magmatic activity in the Qingshan period had a positive effect on the evolution of the source rocks but was not the key factor: burial depth was. (3) Oil and gas failed to accumulate in the Jiaolai basin because they were destroyed by the lateral tectonic activities. During the right-lateral strike-slip stage (50 ± 5 Ma) during the late Wangshi, the Jiaolai basin was strongly uplifted over a range of more than 1000 m by the Tanlu and Wulian-Mouji fault zones along the boundary. The Wangshi group, as a cap rock, was eroded, and oil and gas overflowed along the fault that reached the surface. The late Wangshi period uplift of the Ri-Qing-Wei basin was less than 1000 m because the source rock was deeper, and the reverse faults in the basin were sealed well. The uplift did little damage to the oil in the Ri-Qing-Wei basin. Above all, tectonic evolution was the main controlling factor of oil accumulation in the study area, and the layers of the Laiyang group in the Ri-Qing-Wei basin have oil and gas potential, making it a prospective target for unconventional offshore oil and gas exploration. Full article

The establishment of a comprehensive framework to identify village development types is crucial to formulate plans for rural development and promote rural revitalization. This study proposed a natural–socioeconomic framework to identify the types of villages based on field survey, statistical data, and multi-source remote sensing images. The framework was constructed by combining the two-dimensional natural suitability/restriction evaluation and the four-dimensional socioeconomic development level evaluation. Then, the modified multiplication-weighted summation method and the coupling coordination degree algorithm were employed to identify the villages’ development types. A total of 774 villages of the Laiyang County, eastern China were used as the study areas to examine the framework. The results demonstrated the following. (1) There were 243,318 and 151 villages with high, moderate, low natural suitability, and 62 villages with natural restrictions; and 158,366 and 250 villages with high, moderate, and low economic development level, respectively. The distribution characteristic of natural evaluation was “high in the southwest and low in the northeast”, and the socioeconomic development level was generally centered on the urban area, which presented a “high–medium–low” circle-layer distribution structure. (2) There were 247 villages with high-level coupling coordination, 464 villages with intermediate coupling coordination, 1 village with low-level coupling coordination, and 62 villages with disordered coupling. (3) Based on the coupling coordination evaluation results, villages in the study area were grouped into five types: urbanization development (31%), construction development (16%), agglomeration linkage development (27%), decrease and improvement development (18%), and relocation and integration development (8%). The framework of villages’ development types identification established in this study can enrich the theory of rural geography, and the applied research results can provide a basis for rural revitalization and development planning. Full article