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941.
Abrupt drought–flood alternation (T1) is a meteorological disaster that frequently occurs during summer in southern China and the Yangtze river basin, often causing a significant loss of rice production. In this study, the response mechanism of yield decline under abrupt drought–flood alternation stress at the panicle differentiation stage was analyzed by looking at the metabolome, proteome as well as yield and physiological and biochemical indexes. The results showed that drought and flood stress caused a decrease in the yield of rice at the panicle differentiation stage, and abrupt drought–flood alternation stress created a synergistic effect for the reduction of yield. The main reason for the decrease of yield per plant under abrupt drought–flood alternation was the decrease of seed setting rate. Compared with CK0 (no drought and no flood), the net photosynthetic rate and soluble sugar content of T1 decreased significantly and its hydrogen peroxidase, superoxide dismutase, peroxidase activity increased significantly. The identified differential metabolites and differentially expressed proteins indicated that photosynthesis metabolism, energy metabolism pathway and reactive oxygen species response have changed strongly under abrupt drought–flood alteration stress, which are factors that leads to the rice grain yield reduction.  相似文献   
942.
Han  Chao  Ren  Jinghua  Williams  Paul N.  Ke  Fan  Shen  Qiushi  Wang  Zhaode  Xu  Di  Luo  Jun 《Plant and Soil》2019,441(1-2):613-627
Plant and Soil - Radial oxygen loss (ROL) for macrophytes is intimately involved in their survival and growth, thus detailed characterizations of ROL and its implication for geochemical processes...  相似文献   
943.
944.
In this study, the denitrification performance of the mixotrophic biological reactor was investigated under varying Fe(II)/Mn(II) molar ratio conditions. Results indicate that the optimal nitrate removal ratio occurred at an Fe(II)/Mn(II) molar ratio of 9:1, pH of 7, with an HRT of 10?h. When the reactor was performing under optimal conditions, the nitrate removal reached 100.00% at a rate of 0.116?mmol·L?1·h?1. The proportion of oxidized Fe(II) and Mn(II) reached 99.29% and 21.88%, respectively. High-throughput sequencing results show that Pseudomonas was the dominant species in the mixotrophic biological reactor. Furthermore, the relative abundance of Pseudomonas and denitrification performance was significantly influenced by variation in the Fe(II)/Mn(II) molar ratio.  相似文献   
945.
Peng  Wei  Xu  Shangrong  Zhang  Jun  Zhang  Yong 《Biological trace element research》2019,188(1):189-195
Biological Trace Element Research - The thioredoxin-like (Rdx) family proteins contain four selenoproteins (selenoprotein H, SELENOH; selenoprotein T, SELENOT; selenoprotein V, SELENOV;...  相似文献   
946.
Zhou  Yang  Fu  Yu  Bai  Zhendong  Li  Peixin  Zhao  Bo  Han  Yuehua  Xu  Ting  Zhang  Ningyan  Lin  Lin  Cheng  Jian  Zhang  Jun  Zhang  Jing 《Biological trace element research》2019,187(1):172-180
Biological Trace Element Research - The purpose of this study was to evaluate the protective effect of Du-Zhong cortex extract (DZCE) on lead acetate-induced bone loss in rats. Forty female...  相似文献   
947.
Huang  Feiyi  Liu  Tongkun  Tang  Jun  Duan  Weike  Hou  Xilin 《Plant molecular biology》2019,100(1-2):19-32
Key message

BcMAF2 plays a key role in flowering regulation by controlling BcTEM1, BcSOC1 and BCSPL15 in Pak-choi.

Abstract

Flowering is a key event in the life cycle of plants. Flowering time shows an extensive variation from different Pak-choi (Brassica rapa ssp. chinensis) cultivars. However, the regulation mechanism of flowering in Pak-choi remains rarely known. In this study, a systematic identification and functional analysis of a Pak-choi MADS Affecting Flowering (MAF) gene, BcMAF2, was carried out. BcMAF2 encoded a protein containing a conserved MADS-box domain, which was localized in the nucleus. QPCR analysis indicated that the expression of BcMAF2 was higher in the leaves and flowers. Overexpression of BcMAF2 in Arabidopsis showed that BcMAF2 repressed flowering, which was further confirmed by silencing endogenous BcMAF2 in Pak-choi. In addition, Tempranillo 1 (TEM1) expression was up-regulated and MAF2 expression was down-regulated in the BcMAF2-overexpressing Arabidopsis. The expression of BcMAF2 and BcTEM1 was down-regulated in BcMAF2-silencing Pak-choi plants. The yeast one-hybrid, dual luciferase and qPCR results revealed that BcMAF2 protein could directly bind to BcTEM1 promoter and activate its expression, which was not reported in Arabidopsis. Meanwhile, a self-inhibition was found in BcMAF2. Taken together, this work suggested that BcMAF2 could repress flowering by directly activating BcTEM1.

  相似文献   
948.
Photosynthesis Research - Crassulacean acid metabolism (CAM) is a specialized photosynthetic pathway present in a variety of genera including many epiphytic orchids. CAM is under circadian control...  相似文献   
949.
The complete mitogenome of Haliotis iris, an economically important shellfish endemic to New Zealand, was sequenced for the first time. The mitogenome was 17,131?base pairs (bp) in length and contained 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and a control region. All 13 genes were initiated by the start codon ATG, except for nad5 (ATA). Two typical stop codons, TAA and TAG, were present. All of the tRNAs could be folded into typical cloverleaf secondary structures except tRNASer1 and tRNALys, which lacked a DHU stem and complete amino acid acceptor stem, respectively. The control region was 1132?bp in length and contained six AT tandem repeats. According to the gene order of the mitogenome, the 30 analysed Vetigastropoda species could be classified into three types—type I: over half of the studied species were very similar to the gastropod ancestral gene order, and the rearrangements occurred in five tRNAs; type II: eight species were found to be missing several tRNA genes; type III: Fissurellidae, Lepetodrilidae showed a large inverted fragment.  相似文献   
950.
Liu  Wencong  Xu  Yongtao  Li  Zekun  Fan  Jun  Yang  Yi 《Molecular biology reports》2019,46(6):6087-6098
Molecular Biology Reports - The complete genome sequence provides the opportunity for genome-wide and coding region analysis of SSRs in the king cobra and for cross-species identification of...  相似文献   
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