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Low levels of concern about anthropogenic climate change have been attributed to a range of factors, some of which relate to education. These include people's lack of understanding and engagement with the multifaceted nature and extent of the problem that it presents to current and future generations. Limited knowledge is also known to be an obstacle to individual behaviour change, with important implications for young people's perceptions of the urgency to act and awareness of the consequences of their own behaviours. In this study, we explored ways to address low levels of understanding about ocean science dimensions to climate change phenomena, cognisant of a growing awareness that formal education curricula do not adequately engage young people with developing ocean literacy. Participants were a sample of secondary school students (11 to 14 years) in Portugal and the UK. Using a gamified mobile application, it was examined relationships between the use of different game elements such as points, badges and leaderboards, and learning outcomes. Systematic evaluation of each element shows how different game features affected the participants' learning experience and learning outcomes. Implications for formal and informal marine education, climate education, and how to improve ocean literacy efforts, are also discussed.

Desert truffles are edible hypogeous fungi forming ectendomycorrhizal symbiosis with plants of Cistaceae family. Knowledge about the reproductive modes of these fungi and the molecular mechanisms driving the ectendomycorrhizal interaction is lacking. Genomes of the highly appreciated edible desert truffles Terfezia claveryi Chatin and Tirmania nivea Trappe have been sequenced and compared with other Pezizomycetes. Transcriptomes of T. claveryi × Helianthemum almeriense mycorrhiza from well-watered and drought-stressed plants, when intracellular colonizations is promoted, were investigated. We have identified the fungal genes related to sexual reproduction in desert truffles and desert-truffles-specific genomic and secretomic features with respect to other Pezizomycetes, such as the expansion of a large set of gene families with unknown Pfam domains and a number of species or desert-truffle-specific small secreted proteins differentially regulated in symbiosis. A core set of plant genes, including carbohydrate, lipid-metabolism, and defence-related genes, differentially expressed in mycorrhiza under both conditions was found. Our results highlight the singularities of desert truffles with respect to other mycorrhizal fungi while providing a first glimpse on plant and fungal determinants involved in ecto to endo symbiotic switch that occurs in desert truffle under dry conditions.

Simple Summary: Huanglongbing (HLB) is the most devastating citrus disease across Africa, America and Asia. It is associated with three species of bacteria belonging to the genus 'Candidatus Liberibacter', transmitted by the psyllid vector Trioza erytreae, among others. This insect has spread throughout part of the Iberian Peninsula, threatening citrus orchards with the possible arrival and transmission of HLB. Currently, there are no curative methods of control for the disease, so finding plant material less suitable for psyllids can reduce the risk of spreading. We have evaluated how the citrus combination, rootstocks (Flying dragon, 'Cleopatra' mandarin, Carrizo citrange, Forner-Alcaide no.5, Forner-Alcaide no.517 and Citrus macrophylla) and scion cultivars ('Star Ruby', 'Clemenules', 'Navelina', 'Valencia Late', 'Fino 49' and 'Ortanique') determine the biology of T. erytreae. Our results show that T. erytreae behaves differently depending on the combination, and is the least suitable for its survival with 'Ortanique' on Forner-Alcaide no. 517 and 'Valencia Late' on Carrizo citrange. The psyllid preferred 'Fino 49' grafted onto Carrizo citrange for egg laying rather than Flying Dragon. Trioza erytreae (Del Guercio, 1918) (Hemiptera: Triozidae) is a citrus pest which produces gall symptoms on leaves and transmits bacteria associated with the citrus disease Huanglongbing, 'Candidatus Liberibacter' spp. In the present work, the biology and behaviour of T. erytreae were studied in different rootstock–cultivar combinations. Six rootstocks were used, Flying dragon (FD), 'Cleopatra' mandarin (CL), Carrizo citrange (CC), Forner-Alcaide no.5 (FA5), Forner-Alcaide no.517 (FA517) and Citrus macrophylla (CM), and six scion cultivars: 'Star Ruby', 'Clemenules', 'Navelina', 'Valencia Late', 'Fino 49' and 'Ortanique'. Survival and oviposition were evaluated in a no-choice trial, and preference in a choice trial, all of them under greenhouse conditions. Trioza erytreae did not show a clear settle preference for any citrus combination. However, it was able to lay more eggs in 'Fino 49' grafted on CC than on FD. In terms of survival, 'Ortanique' grafted onto FA5 was more suitable than when grafted onto FA517, and in the case of 'Valencia Late', when it was grafted onto CM rather than CC. Our results showed that T. erytreae behave differently depending on the citrus combination. [ABSTRACT FROM AUTHOR]

Even though super-high-density plantation systems could maximise yield per acre and induce an early entry production, a few research studies have been conducted on citrus crops in the Mediterranean Basin. In this study, we assessed the suitability of 'Salustiana' orange trees (Citrus sinensis) on two dwarfing rootstocks [Forner-Alcaide 418 (FA418) and Forner-Alcaide 517 (FA517)] under super-high-density plantation systems. Tree growth, yield and fruit quality of 'Salustiana' on both citrus rootstocks were evaluated. Furthermore, the suitability of mechanical harvesting was evaluated using an over-the-row continuous canopy shaker for this citrus plantation system. For this last purpose, the effects of mechanical harvesting on fruit detachment and fruit harvested and tree damage were analysed. The results showed that 'Salustiana' orange on FA517 obtained a better response than on FA418 in terms of vegetative growth, effective yield and fruit quality under super high-density conditions, also displaying a better response to mechanical harvesting with a high detachment efficiency of fruits. It emphasised the relevance of proper mechanical pruning to reduce the tree damage and improve the detachment efficiency by this canopy shaker. Thus, although the over-the-row canopy shaker requires some technical improvements, it showed a high potential for harvesting super-high-density citrus crops for the juice industry. [ABSTRACT FROM AUTHOR]

This paper proposes a new automatic tuning method for the proportional-integral (PI) controllers of photovoltaic irrigation systems (PVIS) without the need for any other power source or batteries. It enables the optimisation of the values of the PI parameters ( K p and K i ) automatically, eliminating the requirement for skilled personnel during the installation phase of PVIS. This method is based on the system's voltage response when a disturbance signal is introduced through the feedforward input of the PI controller. To automatically assess the response properties, two indicators are proposed: the total harmonic distortion (THD), used to evaluate the sine response, and the total square distortion (TSD), used to evaluate the square response. The results indicate that the tuning changes for different irradiance and temperature conditions due to the non-linearity of the system, obtaining the most conservative values at maximum irradiance and temperature. The robustness of the results of the new automatic tuning method to abrupt photovoltaic (PV) power fluctuations due to clouds passing over the PV generator has been experimentally tested and the results show that the obtained tuning values make the PVIS stable, even when PV power drops of 66% occur abruptly. [ABSTRACT FROM AUTHOR]