Rice, wheat and maize are the main staple food crops to ensure the food security in China with diversified climate condition, cropping system and environmental and socio-economic factors across provinces. Spatial variation of technical efficiency in farmers’ field is helpful to understand the potential to improve farmers’ yield given the inputs level and reduce the yield gap. The study is based on a large-scale farm household survey which covered 1 218 rice farmers, 3566 wheat farmers and 2 111 maize farmers in the main producing areas. The results indicate that rice farmers are with very high technical efficiency level, nearly 0.9 on average, with little room to improve the efficiency of agricultural inputs. Similar results have been found in wheat and maize farmers’ fields, although the technical efficiency levels are lower than that of rice farmers while still at a high level with obvious variation across regions. Farmers with higher yield level also achieve better technical efficiency in most locations. Both local environmental and socio-economic factors significantly affect farmers’ technical efficiency. In the context of urbanization and economic development, improved and new agricultural technologies need to be prioritized and facilitated to improve cereal yield at farm level.

Purpose: This paper aims to figure out the relationship between energy consumption flow from a new perspective of embodied energy inventory index (EEII) and regional economic growth. Design/methodology/approach: The input-output approach has been applied to calculate embodied energy inventory (EEI) and EEII using the data of 25 economies. Meanwhile, cluster analysis and panel data modeling were applied to carry out detailed research. Findings: The results of cluster analysis show that there is a roughly negative relationship between EEII and gross domestic product (GDP) per capita, although there are some exceptions, such as Russia and Taiwan (Province of China). Panel data model results provide further evidence that there is a negative relationship between EEII and GDP per capita. Population is an important productive factor in the regional economic development. The study showed a positive relationship between EEII and population. Therefore, energy consumption flow is closely related to regional economic development. Originality/value: The value of this paper is to use EEI and EEII to comprehensively clarify the energy consumption flow. The advantage of EEII is that it can reflect the energy embodied in fixed assets and infrastructure.

Higher-yielding rice varieties adapted to the upland conditions of Yunnan were developed and disseminated during the late 1990s. Using cross-sectional farm-level data of 448 households collected from five prefectures in Southern Yunnan, this paper carries out an econometric analysis of the determinants of variations in the adoption of improved varieties among households and assesses the impact of adoption on rice income and total household income. The two major determinants of adoption were found to be the government programs for extension of improved upland rice varieties and for terracing of sloping fields. The presence of government programs for extension and for terracing contributed to increased adoption of improved varieties. Household-specific factors such as land and labor endowments were less important as these variables had a statistically insignificant impact on adoption. The adoption of improved rice varieties increased both rice income and the average household income. About half of the household income difference observed between the full adopters and non-adopters of improved rice varieties with comparable household characteristics can be attributed directly to the adoption. The results imply that increased investments in promoting improved rice varieties and terracing will generate additional income growth in the uplands of Yunnan.