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This study aimed to analyze the difference in aroma components and aroma characteristics of different types (white, oolong, yellow and black) of fermented Lingyun Baihao tea. The aroma components were identified by solid phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS), and odor activity value (OAV) was used to determine the key flavor components. By combined use of principal component analysis (PCA), orthogonal partial least square-discriminant analysis (OPLS-DA), cluster analysis and sensory evaluation, the aroma of fermented Lingyun baihao tea was comprehensively evaluated. The results showed that a total of 48 aroma compounds were identified in the tea samples, including 15 key flavor components and flavor-modifying components (OAV > 0.1). The cumulative interpretation rate R2X (cum) and the cumulative prediction rate Q2 (cum) of the PCA model were 0.984 and 0.846, respectively, and those of the OPLS-DA model were greater than 0.7 and 0.9, respectively. Both models had good fitness. The major differential components were linalool, isoamyl alcohol, 2-methylbutyraldehyde, β-ionone, nonanal and jasmone. The 15 aroma components were classified into three categories by hierarchical cluster analysis (HCA). Class I contained indole and dehydroalinalool, Class II contained linalool, nonanal, phenylacetaldehyde, hexanal, 2-methylbutyraldehyde, isovaleraldehyde, phenylethanol and isobutyraldehyde, and Class III contained jasmone, β-ionone, methyl salicylate, 2-pentylfuran and dimethyl sulfide. Class I was prominent in oolong tea samples, Class II was prominent in black tea samples, Class III was prominent in white tea samples, and Class II and III were prominent in yellow tea samples. These aroma characteristics were consistent with the results of sensory aroma evaluation. GC-MS analysis and OAV calculation combined with PCA, OPLS-DA and HCA can enable the identification and evaluation of Lingyun Baihao fermented tea aroma. The results of this study can provide a reference for the further development of Lingyun Baihao tea.

Achieving global food security requires an understanding of the current status and the future trends in the yield gap for cropping systems worldwide. The aim of this study was to scientifically understand the existing yield gap research, recognize the knowledge base and influential articles, and uncover key research themes and how these have evolved over the past three decades. Bibliometric methods were used to analyze articles related to the yield gap available in the largest scientific database, the Web of Science. A total of 6049 relevant articles published from 1993 to 2023 were numerically analyzed for patterns, trends, and clusters. The findings identified a few primary authors of widely cited publications. Geographically, the United States and China were the two major contributors to the publication pool, with articles from China mostly affiliated with the Chinese Academy of Sciences and China Agricultural University, while the United States had a more scattered distribution of affiliated institutions. The research on yield gaps primarily focused on biological factors, such as the effects of crop varieties, agronomic management, climate change, and soil conditions, with a limited exploration of social and economic factors. Within the auspices of the current food issues worldwide, this study provides a thorough view of the progress and key topics in crop yield gap research, contributing to the existing body of knowledge and providing guidance for researchers, policymakers, and stakeholders involved in agricultural productivity enhancement and sustainable food production. Amid the increasing trend in hunger worldwide over the past decade, we thus concluded that, by establishing appropriate benchmarks, re-prioritizing research needs, and focusing on transforming natural resources rather than inputs, the crop yield gap approach can be useful in terms of the clear inclusion of local contexts and socioeconomic constraints. [ABSTRACT FROM AUTHOR]

In order to comprehensively evaluate the eco-environmental influence on characteristic imitation wild cultivation of Anoectochilus roxburghii under forest in Southern China, the life cycle assessment method was applied to quantitatively assess the environmental impact of this model. The results showed that life cycle environmental impacts of 1 kg of A. roxburghii cultivated under forest were 16 702.27 MJ of primary energy demand, 0.58 m² of land use, and 13.45 t of water use, respectively, this model made full use of the open space under the forest and occupied less land resources. However, this model also brought great potential environmental impact, the aggregate life cycle environmental impact index was 0.327 6, and the potential impact of water toxicity and eutrophication was large. For 1 kg A. roxburghii life cycle environmental impacts of this model were 2 405.83 kg CO2-eq of global warming potential, 4.99 kg SO2-eq of acidification potential, 1.43 kg PO4-eq of eutrophication potential, 1.32, 5.31, 1.09 kg 1, 4-DCB-eq of human toxicity, water toxicity and soil toxicity, respectively. The potential negative impact on the environment was mainly based on the agricultural material system, and the production of tissue culture seedlings accounted for the highest proportion. Therefore, making improvements in tissue culture seedling production, pesticide application, etc. were the key ways to control the environmental impacts of A. roxburghii production under forest. [ABSTRACT FROM AUTHOR]

Potato is an important crop in the Northwest China, however, its production is constrained by water scarcity. Plastic mulching film is an efficient technical measure to alleviate potato production restrictions. Therefore, studying the response of potato yield and water use efficiency to plastic mulching film is of great significance. The study conducted a meta-analysis to quantify the effect of plastic film on potato yield and water use efficiency in the Northwest. The study then quantified the effects of different levels of natural conditions (mean annual precipitation, mean annual accumulated temperature ≥ 10 °C), fertilizer application (nitrogen fertilizer, phosphate fertilizer, potassium fertilizer), cultivation measures (planting density, cultivation method, mulching method), and mulching properties (mulching color, mulching thickness) through subgroups analysis. Finally, the random forest model was used to quantify the importance of factors. Plastic film mulching increased yield by 27.17% and water use efficiency by 27.16%, which had a better performance under relatively lower mean annual precipitation, low mean annual accumulated temperature ≥ 10 °C, relatively lower fertilizer application, planting density of 15,000–45,000 plants·ha−1, ridge, and black mulching. Natural conditions, fertilization measures were vital to improve productivity. The research results can provide reference for agricultural management strategies of potato cultivation using plastic film in the Northwest China and other potato-producing areas. [ABSTRACT FROM AUTHOR]