Search

Simple Summary: Three bark beetle species, Tomicus yunnanensis, T. brevipilosus, and T. minor, are the most economically significant pests of the Yunnan pine in Southwestern China. Chemical and physical communication play key roles in various life activities. In this study, we described the fine structure of the adult mouthparts of these three Tomicus species using scanning and transmission electron microscopy. We identified three types of mandibular shapes, which match with their biomechanical properties, their ability to process food, and their preferred foraging locations on tree trunks. Eleven types of sensilla were discernible, including sensilla basiconica, sensilla twig basiconica, sensilla coeloconica, sensilla chaetica, sensilla trichoidea, and sensilla digitiformia. The function roles of each sensilla type were given based on its distribution and structures, especially on the internal structures such as dendrites and tubular body. Most chemoreceptors occur on the palpal tips. No significant differences among the sexes or species were identified; however, intraspecific variability in the number of sensilla twig basiconica 3 and sensilla digitiformia sensilla was evident. These findings will aid future studies of the feeding niches and reproductive behaviors of Tomicus beetles. Tomicus yunnanensis, T. brevipilosus, and T. minor are the most economically significant pests of Pinus yunnanensis in Southwestern China. Chemical and physical factors play critical roles in diverse biological activities. Here, we describe the fine structure of the adult mouthparts of these three Tomicus species using scanning and transmission electron microscopy. We identified three types of mandibular shapes, which determine their biomechanical properties, their ability to process food, and their preferred foraging locations on tree trunks. Eleven types of sensilla were discernible, including sensilla basiconica (Sb.1–2), sensilla twig basiconica (Stb.1–3), sensilla coeloconica (Sco), sensilla chaetica (Sch.1–2), sensilla trichoidea (Str.1–2), and sensilla digitiformia (Sdi). Each basiconic sensillum occurs on the palpal tips and is innervated by 2–6 dendrites. Sb.1 are gustatory receptors, Sb.2 are olfactory receptors, and the three other sensilla have dual taste and mechanical functions. Sco, Sch, and Str are mechanoreceptors. Sdi are mechanical vibration receptions, given that they are innervated by one dendrite with numerous dendritic branches into the nonporous cuticle. No significant differences among the sexes or species were identified; however, intraspecific variability in the number of Stb.3 and Sdi sensilla was evident. These results will aid future studies of Tomicus beetle behaviors. [ABSTRACT FROM AUTHOR]

Historical hybridization between southern indigenous Chinese cattle and banteng has been well-documented and has resulted in gene introgression. Bitter taste receptors were reported in indigenous cattle as a result of introgression from banteng. To determine the level of introgression of the taste 2 receptor member 16 (TAS2R16) gene from banteng into Chinese cattle, two missense mutations in the bovine TAS2R16 gene were examined. Here, we explored the prevalence of the two variants in 28 indigenous Chinese cattle and banteng breeds (comprising 750 individuals) to determine the influence of banteng introgressions on Chinese cattle based on PCR and DNA sequencing. In our study, the two mutant alleles had a higher frequency distribution in southern China with strong geographic distribution, especially in the south-central and southeast areas. In conclusion, this study examines the impact of introgression on the frequency distributions of mutations in variable regions and the subsequent adaptation of Chinese indigenous cattle to different environmental conditions. [ABSTRACT FROM AUTHOR]

Abstract: China prairie white plumage duck (hereinafter referred to as "prairie duck") is a new variety of meat duck, cultivated independently in China. In order to clarify the muscle quality and nutritional advantages of prairie duck, 36-day-old prairie ducks and cherry valley ducks were selected and raised under the same feeding conditions for the analyses of the nutritional components in ducks' muscles. The moisture, protein and fat contents of prairie duck (76.60%, 19.30% and 1.55%) were lower than those of the cherry valley ducks, but the differences were insignificant (p>0.05). The contents of inosinic acid (0.72 g/kg), carnosine (1.93 g/kg) and homocarnosine (1.68 g/kg) of prairie duck were 20.00%, 8.43% and 11.26% higher than those of cherry valley duck (p<0.05), with the anserine content (0.53 g/kg) being 10.17% significant lower than that of cherry valley duck (p<0.05). The saturated fatty acids (31.52%), monounsaturated fatty acids (40.61%) and polyunsaturated fatty acids (27.42%) of prairie duck were significantly lower, higher and lower, respectively, than those in cherry valley duck. The total amounts of essential amino acids (3.34 g/kg) and umami amino acids (3.46 g/kg) in prairie duck were significantly higher than those in cherry valley duck, with the taurine content (1.41 g/kg) in prairie duck being 16.53% higher than that in the cherry valley duck. In summary, the prairie duck was rich in umami substances such as inosinic acid, carnosine and homocarnosine, and had higher contents of unsaturated fatty acids and umami amino acids, thereby being superior to cherry valley duck. In this study, the quality characteristics of prairie duck meat in terms of delicious taste and rich nutrients were explained based on the differences in the contents of nutrient components. [ABSTRACT FROM AUTHOR]

The woodwasp Sirex noctilio Fabricius is a worldwide quarantine pest for forestry that mainly harms conifers, especially Pinus species. Sirex nitobei Matsumura, a native species from China and closely related to S. noctilio. Olfaction and gustation play a vital role in the life movements of woodwasps, but the molecular mechanisms of chemoperception in these species remain unclear. We performed a comparative analysis of 41 odorant receptors (ORs), 13 ionotropic receptors (IRs), and 8 gustatory receptors (GRs) of S. noctilio and 43 ORs, 16 IRs, and 10 GRs of S. nitobei. Phylogenetic analysis showed that two species-specific OR subfamilies were identified in each species. In addition to conserved "antennal IRs", "divergent IRs", including 7 SnocIRs and 7 SnitIRs, were found. Moreover, a sugar receptor subfamily (SnocGR5 and SnitGR11), a carbon dioxide receptor subfamily (SnocGR2/GR3 and SnitGR3), and a fructose receptor subfamily (SnitGR9) emerged, but bitter receptors were not identified. The tissue-specific expression profiles showed 36 ORs were enriched in the antennae of S. noctilio. Among them, 19 ORs were female-biased, whereas 4 ORs (SnocOR6/15/18/30) were male-biased. In addition, 34 ORs were highly expressed in S. nitobei antennae, of which 22 ORs were female-biased, whereas SnitOR2/18/30 were male-biased. Seven IRs were enriched in the antennae of both species, of which SnocIR4, 6, 10, 11, and 12 were significantly male-biased, while SnitIR4, 6, 10, 11, and 12 were significantly female-biased. Three GRs were highly expressed in the antennae of both species. SnocGR2 and SnocGR6 were also highly expressed in the head and leg, respectively. In the present study, a total 62 and 69 chemosensory receptor genes were identified in the antennal transcriptomes of S. noctilio and S. nitobei, respectively. Although most receptor genes are homologous, there are also some specific receptor genes, suggesting similarities and differences in molecular mechanisms between the two closely related species. OR genes may be involved in different physiological functions by whether they are expressed in olfactory organs, or obvious gender bias. Our results provide a foundation for further investigating the molecular mechanisms of chemoreception in these two closely related woodwasp species, and establishes a starting point for further research on molecular mechanisms of the olfactory system in symphyta woodwasps. [ABSTRACT FROM AUTHOR]

This study scrutinizes the effect of the Sewage Charges System (SCS) reform on the green total factor productivity (GTFP) across China's provinces. Employing the global Luenberger productivity indicator based on a non-radial directional distance function, we observe an upward trend in China's GTFP during the study period. However, the SCS reform precipitates a contraction in the GTFP, particularly pronounced in low-income and resource-based provinces of China. Empirical findings withstand a battery of robustness checks of self-selection and placebo tests. Further mechanistic tests suggest that the SCS reform influences the GTFP by escalating pollution treatment costs, curtailing R&D investment, and undermining the quality of green innovation via crowding-out effects. Overall, the SCS reform is effective in curbing SO 2 emissions, but it reduces economic efficiency. Therefore, how to synergize emission reduction and economic growth is an important issue to be addressed in the area of environmental policy design in China. • We evaluate the effect of SCS reform on China's green productivity. • The SCS reform reduces emissions but leads to a decline in green productivity. • The decline in green productivity is subject to crowding-out effects. • The inhibition of SCS reform on GTFP presents only in low-income and resource-based regions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Comprehensive analysis of flavor formation of mandarin fish from smell and taste. • Nineteen key aroma compounds were identified in fermented mandarin fish. • The differential metabolites presented a significant correlation to the key volatiles. • 5′-nucleotides were reduced, whereas Asp and Glu were increased. • Tryptophan metabolism was the potential generation pathway of the fish stinky. Volatolomics and metabolomics were performed to explore the generation mechanism of the characteristic flavor of mandarin fish during fermentation. This study revealed a novel finding that umami-tasting amino acids, succinic acid, and peptides increased, while taste-presenting nucleotides decreased after fermentation. The results showed that 19 key aroma compounds were identified. The most nitrogenous compounds were produced after fermentation, the total concentration of which was >5 mg/kg. A high odor activity value of 443 was established for stinky indole. PLS-DA showed that sn -glycero-3-phosphocholine, hypoxanthine, creatine, and trimethylamine N -oxide were the key metabolites associated with the key volatiles. Umami-tasting amino acids could contribute to the characteristic taste. Metabolic pathway analysis revealed that tryptophan metabolism, trimethylamine metabolism, and monoterpenoid biosynthesis were the potential generation pathways of indole, trimethylamine, and terpenoids, respectively. Collectively, the results provide thoughts for targeted controlling the flavor of fermented mandarin fish. [ABSTRACT FROM AUTHOR]

The development of new food products can be expedited by understanding the physicochemical attributes that are most relevant to consumers. Although many objective analyses are possible, not all are a suitable proxy to serve as quality markers associated with sensory preferences. In this work, we selected nine candidate laboratory assays to use on six commercial salamis, which were also eaten and informally described by a consumer discussion group familiar with China-sourced meat products. Several objective measures were strongly related to the flavour perceptions: (i) texture: instrumental texture values, fat release at oral temperature and fat saturation ratios, (ii) aroma: volatile compounds (e.g., alcohols and esters) associated with microbial fermentation and spices (terpenes and sulphur compounds) and (iii) taste: kokumi taste receptor responses. The fat released at oral temperature was associated with unsaturated fatty acids (r = 0.73). However, there was less explanatory worth for associations between sensory perceptions and proximate composition, water activity, pH or L*, a*, b* colourimetry. [ABSTRACT FROM AUTHOR]