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Uma abordagem integrada na avaliação da qualidade de solos agrícolas em parcelas regadas. Caso de estudo aproveitamento hidroagrícola Brinches-Enxoé, EFMA
Publication . Palma, Patrícia; Martins, Inês; Catarino, Adriana; Mourinha, Clarisse; Alvarenga, Paula; Dores, José; Patanita, Manuel; Tomaz, Alexandra
Response of Malus x domestica Borkh to metamitron and high night temperature: Effects on physiology and fruit abscission
Publication . Rosa, Nídia; Àvila, Glória; Carbó, J.; Verjans, Wim; Bonany, J.; Ramalho, José C.; Asín, L.; Oliveira, Cristina M.
Periods of high nighttime temperature may induce carbohydrate (CH) shortage by increased dark respiration.
Metamitron is a thinning agent that inhibits photosynthesis and enhances fruit abscission due to a reduction in
CH production. To clarify how both interact in apple tree physiologic mechanisms and on fruit abscission, five
field trials were carried out in Lleida, Girona and Sint-Truiden (2017 + 2018), using orchards of ‘Golden’ apple
trees. At the stage of 12–14 mm fruit diameter, four treatments were established: (A) CTR – control, trees under
natural environmental conditions; (B) HNT – high nighttime temperature, trees exposed to artificially increased
nighttime temperature during 5 nights after the day of spraying, without metamitron application; (C) MET -
247.5 ppm of metamitron application and (D) MET + HNT - trees submitted to the combined exposure to
metamitron application (MET) and to artificially increased nighttime temperature (HNT). HNT did not affect
metamitron absorption, net photosynthesis (Pn) and stomatal conductance however, promoted significant reductions
in leaf CH content mainly before sunrise, especially in sucrose (18–45%) and in sorbitol (19–26%).
Metamitron significantly reduced Pn to about 50% of CTR, which resulted in decreases in leaf sucrose and
sorbitol, reaching minimum values 5 days after spraying, between 21 and 57% and 19–26%, respectively. Fruit
growth rate of both treatments was retarded by 30%, 2 days after either metamitron application or HNT. Both
treatments originated a similar reduction in the number of fruits and size improvement. The combined exposure
(MET+HNT) promoted similar Pn reductions as MET, but showed the greatest sucrose (44–60%) and sorbitol
(73–84%) decreases which resulted in the strongest thinning efficacy. Lipid peroxidation was not affected by the
treatments however, antioxidant enzyme activity showed moderate changes with activity increases mainly under
MET and MET + HNT, accompanied by a rise in glutathione content and reduction in ascorbate. This work shows
that the overlap of photosynthesis inhibition (reducing CH production) by means of metamitron spraying, and
likely greater respiration (increased CH consumption), by HNT imposition, translates less CH production than the
growing fruits demand (negative CH balance) leading to a metamitron thinning effect enhancement. Periods of
high nighttime temperature must be considered when deciding the best metamitron rate to achieve an optimal
crop load result
Effectiveness of hermetic containers in controlling paddy rice (Oryza sativa L.) storage insect pests
Publication . Covele, Gervâncio; Gulube, Anacleto; Tivana, Lucas; Ribeiro-Barros, Ana I.; Carvalho, Maria Otilia; Ndayiragije, Alexis; Nguenha, Rafael
Naturally infested paddy rice was used to compare the effectiveness of polypropylene bags and hermetic
storage containers over 12 months of storage in a warehouse. Insect pest identification as well as the
infestation level, percentage of damaged grain, weight loss, and moisture content were evaluated. Five
insect species associated with stored rice were identified during the storage period, namely lesser grain
borer (Rhyzopertha dominica), red flour beetle (Tribolium castaneum), rice/maize weevil (Sitophilus spp.),
angoumois grain moth (Sitotroga cerealella) and flat grain beetle (Cryptolestes ferrugineus). The lesser
grain borer was the most predominant species with an average incidence above 70% after twelve months
of storage, followed by the rice/maize weevil with an incidence of 17%. When compared to hermetic
storage containers, polypropylene bag showed the highest mean infestation level with 233.3 individuals/
kg after six months of storage, representing about 8-fold of the number of insects recorded in hermetic
containers after six months of storage. In polypropylene container, the percentage of damaged grain and
weight loss increased significantly achieving a maximum of 6.98% and 5.56% respectively, whereas using
hermetic containers the highest percentage of damaged grain reached was 3.24% in polyethylene drum
and the weight loss was 1.62% in GrainSafe bag. The results from the study show that the use of hermetic
storage containers is a green alternative for safe storage of paddy rice, for 12 months without application
of pesticides, bringing multiple advantages for smallholder farmers, lever food security and income
generation for smallholder farmers and rice milling companies
Characterising the agriculture 4.0 landscape - Emerging trends, challenges and opportunities
Publication . Araújo, Sara Oleiro; Peres, Ricardo Silva; Barata, José; Lidon, Fernando; Ramalho, José C.
Investment in technological research is imperative to stimulate the development of sustainable
solutions for the agricultural sector. Advances in Internet of Things, sensors and sensor
networks, robotics, artificial intelligence, big data, cloud computing, etc. foster the transition towards
the Agriculture 4.0 era. This fourth revolution is currently seen as a possible solution for
improving agricultural growth, ensuring the future needs of the global population in a fair, resilient
and sustainable way. In this context, this article aims at characterising the current Agriculture 4.0
landscape. Emerging trends were compiled using a semi-automated process by analysing relevant
scientific publications published in the past ten years. Subsequently, a literature review focusing
these trends was conducted, with a particular emphasis on their applications in real environments.
From the results of the study, some challenges are discussed, as well as opportunities for future
research. Finally, a high-level cloud-based IoT architecture is presented, serving as foundation for
designing future smart agricultural systems. It is expected that this work will positively impact the
research around Agriculture 4.0 systems, providing a clear characterisation of the concept along with
guidelines to assist the actors in a successful transition towards the digitalisation of the sector
Elemental composition of algae-based supplements by energy dispersive X-ray fluorescence
Publication . Reboredo, Fernando H.; Junior, Walter; Pessoa, Maria F.; Lidon, Fernando C.; Ramalho, José C.; Leitão, Roberta G.; Silva, Maria Manuela; Alvarenga, Nuno; Guerra, Mauro
The aim of this study is to evaluate the elemental composition of fifteen algae-based
supplements commonly sold in the Portuguese market, by energy dispersive X-ray fluorescence.
Despite the fact that the majority of Kelp samples were a good source of iodine, the levels observed
might well contribute to an excess in the human body, which can cause dysfunction of the thyroid
gland. Furthermore, the presence of lead in Sea spaghetti, Arame, Hijiki and Wakame caused a
considerable risk to public health vis a vis possible ingestion of a high daily dose. Regarding arsenic,
great variability was observed in all the samples with concentrations equal to or above 60 μg/g in
the case of Arame, KelpJ and Hijiki. Although algae mainly accumulate organic arsenic, some also
contain high levels of its inorganic form, as is commonly pointed out for Hijiki. Thus, regular
ingestion of these supplements must also take into account the mentioned facts. There is no doubt
that these supplements are also good sources of other nutrients, but the lack of accurate regulations
and control should alert consumers to avoid indiscriminate use of these types of products
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Fundação para a Ciência e a Tecnologia
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6817 - DCRRNI ID
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157809