Light blocking film in a glasshouse impacts Capsicum annuum L. yield differentially across planting season

High energy costs are a barrier to producing high-quality produce at protected cropping facilities. A potential solution to mitigate high energy costs is film technology, which blocks heat-producing radiation; however, the alteration of the light environment by these films may impact crop yield and quality. Previous studies have assessed the impact of ULR 80 [i.e., light-blocking film (LBF)] on crop yield and photosynthetically active radiation (PAR); however, an assessment of the spectral environment over different seasons is important to understand potential crop impacts through different developmental phases. In this study, two varieties (red and orange) of Capsicum annuum were grown across two crop cycles: one cycle with primary crop growth in the autumn (i.e., autumn experiment [AE]) and the other with primary crop growth in the summer (i.e., summer experiment [SE]). LBF reduced PAR (roof level: 26%-30%, plant canopy level: 8%-25%) and net radiation (36%-66%). LBF also reduced total diffuse PAR (AE: 8%, SE: 15%), but the diffuse fraction of PAR increased by 7% and 9% for AE and SE, respectively, potentially resulting in differential light penetration throughout the canopy across treatments. LBF reduced near-infrared radiation (700 nm-2,500 nm), including far-red (700 nm-780 nm) at mid- and lower-canopy levels. LBF significantly altered light quantity and quality, which determined the amount of time that the crop grew under light-limited (<12 mol m-2 d-1) versus sufficient light conditions. In AE, crops were established and grown under light-limited conditions for 57% of the growing season, whereas in SE, crops were established and grown under sufficient light conditions for 66% of the growing season. Overall, LBF significantly reduced the yield in SE for both varieties (red: 29%; orange: 16%), but not in AE. The light changes in different seasons in response to LBF suggest that planting time is crucial for maximizing fruit yield when grown under a film that reduces light quantity. LBF may be unsuitable for year-round production of capsicum, and additional development of LBF is required for the film to be beneficial for saving energy during production and sustaining good crop yields in protected cropping.

Preparatory labor for chemical fertilizer: Rural modernity and the practices of South Korean farmers in the 1960s

This article examines preparatory labor practices that South Korean farmers had to undertake to use chemical fertilizers in the 1960s. Preparatory labor, such as learning about and acquiring fertilizers, that came prior to the use of chemical fertilizer in the field was mundane and often invisible. However, it was this logistical and emotional labor that was essential for the maintenance of South Korea's chemical fertilizer system. In the system, which was part of the government's efforts to establish rural modernity through increased crop productivity, the state looked down on farmers as the subject of edification. Nevertheless, the farmers were crucial maintainers of the state-led agricultural reform, realizing the government's vision of modernity. To reveal the hidden relationship between farmers, technology, and the state, this article extensively uses diaries written by two farmers - Yoon Heesoo from Daecheon Village and Shin Kwonsik from Daegok Village. By doing so, this article aims to shed light on the voices of farmers and their roles in the agricultural reform of 1960s South Korea and, more broadly, of the Green Revolution.

[Progress on eco-technology classification in ecologically vulnerable regions of China]

Ecological technology is the core of ecological environment governance and restoration in ecologically vulnerable regions. A reasonable classification method is the basis for induction and summary of ecological techno-logy, which is of great significance to classify and solve ecological environmental problems and evaluate the effects of ecological technology implementation. However, there is still no standard method for the classification of ecological technology. From the perspective of ecological technology classification, we summarized the concept of eco-technology and related classification methods, in view of current situation and deficiency of ecological technology related classification, we put forward a system suitable for defining and classifying ecological technology in ecologically vulnerable regions of China, and analyzed the practicality and application prospect. Our review would provide reference for the management and promotion of ecological technology classification.

Underground Wireless Data Transmission Using 433-MHz LoRa for Agriculture

Wireless underground sensor networks (WUSNs) have potential for providing real-time data for agriculture and other industries without exposing sensors and communication infrastructure to damage. However, soil is a difficult environment for radio communication due to its dielectric properties and variable moisture content. Low-power, wide-area network (LPWAN) technologies have been used to develop aboveground sensor networks for many industries, but have not yet been successfully developed for underground applications. In this study, we developed a 433-MHz LoRa-based testbed for evaluating both underground-to-underground (UG2UG) and underground-to-aboveground (UG2AG) wireless communication technologies in four in situ soils. The maximum transmission distance for UG2UG operation was 4-20 m depending on soil type, whilst UG2AG operation was able to communicate up to 100-200 m, depending on the operating variables and soil properties. Signal quality and the maximum transmission distance were influenced by transmitter (TX) burial depth, TX power, data rate, receiver (RX) antenna type, and to a lesser extent, soil parameters. Results suggest that with improvements to power management, the development of 433-MHz LoRa-based UG2AG WUSNs for agricultural applications is readily achievable, whilst UG2UG applications appear unlikely without substantial improvement in transmission distance.

Managing phenol contents in crop plants by phytochemical farming and breeding-visions and constraints

Two main fields of interest form the background of actual demand for optimized levels of phenolic compounds in crop plants. These are human health and plant resistance to pathogens and to biotic and abiotic stress factors. A survey of agricultural technologies influencing the biosynthesis and accumulation of phenolic compounds in crop plants is presented, including observations on the effects of light, temperature, mineral nutrition, water management, grafting, elevated atmospheric CO(2), growth and differentiation of the plant and application of elicitors, stimulating agents and plant activators. The underlying mechanisms are discussed with respect to carbohydrate availability, trade-offs to competing demands as well as to regulatory elements. Outlines are given for genetic engineering and plant breeding. Constraints and possible physiological feedbacks are considered for successful and sustainable application of agricultural techniques with respect to management of plant phenol profiles and concentrations.