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Salinity is one of the main limiting factors driving the expansion of Spartina alterniflora by affecting plant functioning. Comparative studies of plant leaves, under 0 (T0), 5 (T5), 10 (T10), and 20 g/kg (T20) soil salinity, were carried out. Results showed that soil salinity significantly affected most leaf traits of S. alterniflora. Total and live leaf numbers first increased and then decreased with increasing soil salinity. Leaf morphology in T5 were substantially larger than another three treatments, and the ratio of leaf length to width considerably decreased with increasing soil salinity. As the soil salinity increased, leaf dry mass and leaf dry matter content (LDMC) displayed a pattern similar to total leaf number. Leaf mass traits indicated that while a more efficient nutrient conservation strategy was adopted in T10, S. alterniflora rapidly produced biomass in T0. Strong correlations were observed between leaf morphological and mass traits except for some parts of LDMC. The confidence ellipses of leaf traits indicated significant differences in leaf traits of the four treatments. We believe that insights into the aforementioned aspects can contribute to a better understanding of the responses of leaf traits of S. alterniflora and provide valuable information about its adaptation strategy. [ABSTRACT FROM AUTHOR]

Wastewater from agricultural source carries excess nitrogen and phosphorous into wetlands and causes eutrophication in waterbody. Enrichment of nitrogen and phosphorous affects the natural nutrient removal and plant growth in wetlands. We conducted a greenhouse experience to explore the effects of excess N and P on the growth of Carex schmidtii, so as to provide evidence for wetland phytoremediation. The results showed that high concentration of N had negative effects on the plant height and growth rate of C. schmidtii. Excess N and P significantly reduced the leaf morphology and mass per plant or leaf but increased the length and the ratio of withered leaf. Furthermore, the chlorophyll content and lid peroxidation indicated that high concentrations of N and P exerted much injury to the blades of C. schmidtii. These results help in understanding the responses of C. schmidtii to agricultural wastewater and suggest the limited capacity of C. schmidtii tussock for the phytoremediation of agricultural wastewater in wetlands. [ABSTRACT FROM AUTHOR]

Although sphingomyelins known to be are lipid constituents of the plasma membrane in vertebrates, much remains obscure about the metabolism of sphingomyelins in insects. With ultra performance liquid chromatography‐time‐of‐flight‐tandem mass spectrometry analysis, we revealed for the first time that sphingomyelins are abundant in Nilaparvata lugens (Stål), the brown planthopper (BPH), and their biosynthesis is carried out by sphingomyelin synthase‐like protein 2 (SMSL2), which is homologous to sphingomyelin synthase‐related protein (SMSr). Unlike other insect species, high concentrations of sphingomyelins rather than ceramide phosphoethanolamines exist in the BPH. Two putative genes, which are homologous to SMSr, are named Nilaparvata lugensSMS‐like 1 (NlSMSL1) and 2 (NlSMSL2). Knockdowns of both NlSMSL2 and NlSMSL1 were conducted but only the first decreased concentrations of sphingomyelins in the BPH, indicating that NlSMSL2 plays a role in the biosynthesis of sphingomyelins. Real‐time quantitative PCR analysis revealed both NlSMSL1 and NlSMSL2 are highly expressed in BPH adults, with NlSMSL1 specifically highly expressed in reproductive organs (ovaries and testes) whereas NlSMSL2 was highly expressed in the malpighian tubules. The knockdown of NlSMSL1 or NlSMSL2 increased BPH female body weight but not that of males, suggesting sex‐specific roles for SMSLs in influencing BPH body weight. The results suggest that NlSMSL2 catalyses the synthesis of sphingomyelins and maintains female BPH body weight through alteration of sphingolipid content. [ABSTRACT FROM AUTHOR]

The neutral sphingomyelinase (nSMase) 1 homologue gene LsSMase was cloned from Laodelphax striatellus, a direct sap-sucker and virus vector of gramineous plants, and expressed via a Bac to Bac baculovirus expression system. The LsSMase-enhanced green fluorescent protein fusion protein was located in the endoplasmic reticulum in a similar manner to mammalian nSMase 1. The biochemical properties of LsSMase were determined in detail. The optimal pH and temperature for recombinant LsSMase were 8 and 37 °C, respectively. LsSMase was an Mg2+ or Mn2+ dependent enzyme, but different concentration of each were needed. The activity of LsSMase was significantly stimulated by Ethylene glycol bis(2-aminoethyl ether)tetraacetic acid (EGTA), whereas it was inhibited by ethylenediaminetetraacetic acid. Millimolar concentrations of Zn2+ completely inhibited LsSMase. The reducing agents dithiothreitol and β-mercaptoethanol varied in their effects on activity. Phospholipids were not found to stimulate LsSMase. [ABSTRACT FROM AUTHOR]

The hybrid improper ferroelectricity (HIF) has been proposed as a promising way to create multiferroic materials with strong magnetoelectric coupling by the first-principle calculation, and the experimental evidences of HIF in Ruddlesden-Poper Ca3(Ti1-xMnx)2O7 (x=0, 0.05, 0.1, and 0.15) ceramics have been shown in the present work. The room temperature ferroelectric hysteresis loops are observed in these ceramics, and a polar orthorhombic structure with two oxygen tilting modes has been confirmed by the X-ray powder diffraction. A first-order phase transition around 1100K in Ca3Ti2O7 was evidenced, and the temperatures of phase transitions decrease linearly with increasing of the contents of Mn4+ ions. Based on the result of first-principle calculations, the polarization should be reversed by switching through the mediated Amam phase in Ca3Ti2O7 ceramics. [ABSTRACT FROM AUTHOR]