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961.
Qiuxia Wang Congcong Liu Lili Xu Fangzhou Zhuang Bo Guan Guangcan Lin Chengdong Peng 《Zeitschrift fur angewandte Ichthyologie》2020,36(4):542-544
Parameters of the length-weight relationship (LWR) were estimated for four fish species [Beaufortia szechuanensis (Fang, 1930), Claea dabryi (Sauvage, 1874), Percocypris pingi (Tchang, 1930), and Yunnanilus sichuanensis Ding, 1995] from the Yalong River. Samples were collected seasonally from June 2018 to July 2019, using various fishing gears [set nets (mesh: 1.5 × 2.0 cm), hook, drift gill nets (three mesh sizes: 1.0; 2.0; 3.0 cm) and electro fishing]. Two new maximum standard length were recorded for C. dabryi and P. pingi. 相似文献
962.
963.
Xishuai Tong Roman R. Ganta Zongping Liu 《Biology of the cell / under the auspices of the European Cell Biology Organization》2020,112(9):251-264
Osteoclasts are multinucleated giant cells, responsible for bone resorption. Osteoclast differentiation and function requires a series of cytokines to remove the old bone, which coordinates with the induction of bone remodelling by osteoblast-mediated bone formation. Studies have demonstrated that AMP-activated protein kinase (AMPK) play a negative regulatory role in osteoclast differentiation and function. Research involving AMPK, a nutrient and energy sensor, has primarily focused on osteoclast differentiation and function; thus, its role in autophagy, inflammation and immunity remains poorly understood. Autophagy is a conservative homoeostatic mechanism of eukaryotic cells, and response to osteoclast differentiation and function; however, how it interacts with inflammation remains unclear. Additionally, based on the regulatory function of different AMPK subunits for osteoclast differentiation and function, its activation is regulated by upstream factors to perform bone metabolism. This review summarises the critical role of AMPK-mediated autophagy, inflammation and immunity by upstream and downstream signalling during receptor activator of nuclear factor kappa-B ligand-induced osteoclast differentiation and function. This pathway may provide therapeutic targets for bone-related diseases, as well as function as a biomarker for bone homoeostasis. 相似文献
964.
965.
966.
Huiyun Li Ye Liu Sumei Chen Jiafu Jiang Aiping Song Weimin Fang Fadi Chen 《Phyton》2020,89(4):851-859
Black spot disease, caused by the necrotrophic fungus Alternaria
tenuissima (Fr.) Wiltsh (A. tenuissima), is considered a highly destructive disease
of Chrysanthemum (Chrysanthemum morifolium Ramat.). A set of 17 accessions
of commercial chrysanthemum cultivars were evaluated for resistance to A.
tenuissima by seedling artificial inoculation. It was found that the reaction of
the accessions to artificial inoculation ranged from resistant to highly susceptible.
Five varieties of chrysanthemum (‘Zhongshan Taogui’, ‘Jinba’, ‘Zhongshan Jinguan’, ‘Jinling Wanhuang’ and ‘Jinling Yangguang’) were resistant; two varieties
of chrysanthemum (‘Zhongshan Xinggui’ and ‘Zhongshan Jinkui’) were moderately resistant; and others were susceptible to various degrees, four varieties of
chrysanthemum (‘Zhongshan Zihe’, ‘Zhongshan Jiuhong’, ‘Zaoyihong’ and ‘Jinling Jiaohuang’) were highly susceptible, especially. Some leaf morphological features of two resistant and two highly susceptible cultivars were further researched.
Trichome density, length, height, gland size and stomata density were found to be
associated with plant passive resistance. Resistant varieties that were identified in
present study will be promising germplasm for exploitation of breeding programmes aimed at developing A. tenuissima-resistant cultivars and increasing
genetic diversity. 相似文献
967.
Lidong Liu Xiuyun Zhao Yong Huang Luxin Ke Rui Wang Gaofu Qi 《Physiologia plantarum》2020,170(2):158-171
Plant growth-promoting rhizobacteria (PGPRs) confer benefits to crops by producing volatile organic compounds (VOCs) to trigger induced systemic tolerance (IST). Here we show that Bacillus velezensis GJ11, a kind of PGPRs, produce VOCs such as 2,3-butanediol and acetoin to trigger IST and cause stomatal closure against O3 injury in tobacco plants. Compared to 2,3-butanediol, acetoin was more effective on triggering IST against O3 injury. The bdh-knockout strain GJ11Δbdh with a blocked metabolic pathway from acetoin to 2,3-butanediol produced more acetoin triggering stronger IST against O3 injury than GJ11. Both acetoin and GJ11Δbdh effectively enhance the antioxidant enzymes activity (e.g. superoxide dismutase and catalases) that is favorable for scavenging the reactive oxygen species like H2O2 in leaves after exposure to O3. Consequently, less H2O2 accumulation was observed, and reasonably less chlorophylls and proteins were damaged by H2O2 in the tobacco leaves treated with acetoin or GJ11Δbdh. The field experiment also showed that both acetoin and GJ11Δbdh could protect tobacco plants from O3 injury after application by root-drench. This study provides new insights into the role of rhizobacterial B. velezensis and its volatile component of acetoin in triggering defense responses against stresses such as O3 in plants. 相似文献
968.
Rui Li Liu Wang Yujing Li Ruirui Zhao Yuelin Zhang Jiping Sheng Peihua Ma Lin Shen 《Physiologia plantarum》2020,170(4):569-579
Tomato is one of the most popular horticultural crops, and many commercial tomato cultivars are particularly susceptible to Botrytis cinerea. Non-expressor of pathogenesis-related gene 1 (NPR1) is a critical component of the plant defense mechanisms. However, our understanding of how SlNPR1 influences disease resistance in tomato is still limited. In this study, two independent slnpr1 mutants were used to study the role of SlNPR1 in tomato resistance against B. cinerea. Compared to (WT), slnpr1 leaves exhibited enhanced resistance against B. cinerea with smaller lesion sizes, higher activities of chitinase (CHI), β-1, 3-glucanases (GLU) and phenylalanine ammonia-lyase (PAL), and significantly increased expressions of pathogenesis-related genes (PRs). The increased activities of peroxidase (POD), ascorbate peroxidase (APX) and decreased catalase (CAT) activities collectively regulated reactive oxygen species (ROS) homeostasis in slnpr1 mutants. The integrity of the cell wall in slnpr1 mutants was maintained. Moreover, the enhanced resistance was further reflected by induction of defense genes involved in jasmonic acid (JA) and ethylene (ET) signaling pathways. Taken together, these findings revealed that knocking out SlNPR1 resulted in increased activities of defense enzymes, changes in ROS homeostasis and integrity of cell walls, and activation of JA and ET pathways, which confers resistance against B. cinerea in tomato plants. 相似文献
969.
Plant and Soil - Although the linkages between aboveground photosynthates production and belowground respiration processes have been well studied, doubts remain as to the extent that photosynthate... 相似文献
970.
Jing Zhang Mingjian Zhou Zhenglin Ge Jie Shen Can Zhou Cecilia Gotor Luis C. Romero Xingliang Duan Xin Liu Deliang Wu Xianchao Yin Yanjie Xie 《Plant, cell & environment》2020,43(3):624-636
Recent studies have demonstrated that hydrogen sulfide (H2S) produced through the activity of l -cysteine desulfhydrase (DES1) is an important gaseous signaling molecule in plants that could participate in abscisic acid (ABA)-induced stomatal closure. However, the coupling of the DES1/H2S signaling pathways to guard cell movement has not been thoroughly elucidated. The results presented here provide genetic evidence for a physiologically relevant signaling pathway that governs guard cell in situ DES1/H2S function in stomatal closure. We discovered that ABA-activated DES1 produces H2S in guard cells. The impaired guard cell ABA phenotype of the des1 mutant can be fully complemented when DES1/H2S function has been specifically rescued in guard cells and epidermal cells, but not mesophyll cells. This research further characterized DES1/H2S function in the regulation of LONG HYPOCOTYL1 (HY1, a member of the heme oxygenase family) signaling. ABA-induced DES1 expression and H2S production are hyper-activated in the hy1 mutant, both of which can be fully abolished by the addition of H2S scavenger. Impaired guard cell ABA phenotype of des1/hy1 can be restored by H2S donors. Taken together, this research indicated that guard cell in situ DES1 function is involved in ABA-induced stomatal closure, which also acts as a pivotal hub in regulating HY1 signaling. 相似文献