Summary The nutritional traits of maize kernels are important for human and animal nutrition, and these traits have undergone selection to meet the diverse nutritional needs of humans. However, our knowledge of the genetic basis of selecting for kernel nutritional traits is limited. Here, we identified both single and epistatic quantitative trait loci (QTLs) that contributed to the differences of oil and carotenoid traits between maize and teosinte. Over half of teosinte alleles of single QTLs increased the values of the detected oil and carotenoid traits. Based on the pleiotropism or linkage information of the identified single QTLs, we constructed a trait–locus network to help clarify the genetic basis of correlations among oil and carotenoid traits. Furthermore, the selection features and evolutionary trajectories of the genes or loci underlying variations in oil and carotenoid traits revealed that these nutritional traits produced diverse selection events during maize domestication and improvement. To illustrate more, a mutator distance–relative transposable element (TE) in intron 1 of DXS2, which encoded a rate‐limiting enzyme in the methylerythritol phosphate pathway, was identified to increase carotenoid biosynthesis by enhancing DXS2 expression. This TE occurs in the grass teosinte, and has been found to have undergone selection during maize domestication and improvement, and is almost fixed in yellow maize. Our findings not only provide important insights into evolutionary changes in nutritional traits, but also highlight the feasibility of reintroducing back into commercial agricultural germplasm those nutritionally important genes hidden in wild relatives.

In many parts of China, rapid economic growth, socio-economic inequality, and environmental degradation (air, water, soil) are undermining social stability and sustainable urbanization. Ruralurban migration is the main factor contributing to urban population growth. Economic opportunity in urban areas is the main 'pull factor' but government policies provide a 'push factor'. A model of the relationship over time of the rural sector and the urban sectors, mainly relating to the focus on manufacturing and the services sector, is discussed. Each sector provides a market for the other. We use three cameos of different types of urban-rural development taking examples from a Prefecture-level city of about 500,000 population located in Guangxi Autonomous Region in south east China. We analyze the infrastructure plan and land use planning in respect to the impact on labor, investment and urban growth. Feng and Squires; SAJSSE, 2(3): 1-13, 2018; Article no.SAJSSE.45575 2 Commentary

The rural-urban (peri-urban) interface zones are important places that generate demands for ecosystem goods and services (EG & S). Urban regions face transitions in land use that affect ecosystem services (EG & S) and thus human wellbeing. Especially in urban areas with high population densities (as in most of China) and high demand for EG & S, the future availability of such services must be considered in order to promote effective and sustainable decision making and prevent further ecosystem degradation. The challenge for local government planners and land managers is to find tools that allow relevant data to be collected and analyzed. Ideally, such tools should be able to give a rapid assessment, and not involve large teams of highly trained personnel or incur high costs. The paper reports on the development and trial of such a tool. The paper has three main parts. First, we present a brief overview of the current and developing situation in China, in relation to urbanization, population shifts and the creation of peri-urban areas (PUAs). Next, we build on insights from the literature and from discussions with village heads and county- and prefecture-level officials to develop an understanding of their needs for tools to help planning and land management within the constraints of the national policy. Lastly, a “template” was derived from our multi-method approach that provided a new technical tool for the rapid assessment of the value of EG & S in each of five land use categories. The tool embodies a way to address trade-offs between environmental, social and economic values in the transition zone between rural and urban areas. The tool was trialed in QinBei District in Guangxi Autonomous Region in south China and judged to be useful and adaptable to other rural–urban regions.

Alpine grasslands are a common feature on the extensive (2.6 million km2) Qinghai–Tibet plateau in western and southwestern China. These grasslands are characterized by their ability to thrive at high altitudes and in areas with short growing seasons and low humidity. Alpine steppe and alpine meadow are the principal plant Formations supporting a rich species mix of grass and forb species, many of them endemic. Alpine grasslands are the mainstay of pastoralism where yaks and hardy Tibetan sheep and Bactrian camels are the favored livestock in the cold arid region. It is not only their importance to local semi nomadic herders, but their role as headwaters of nine major rivers that provide water to more than one billion people in China and in neighboring countries in south and south-east Asia and beyond. Grasslands in this region were heavily utilized in recent decades and are facing accelerated land degradation. Government and herder responses, although quite different, are being implemented as climate change and the transition to the market economy proceeds apace. Problems and prospects for alpine grasslands and the management regimes being imposed (including sedentarization, resettlement and global warming are briefly discussed.

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