An unexpected heat resilience, and the mitigation of heat impacts by elevated [CO2] were recently reported in Coffea spp. Plants must maintain membrane fluidity and integrity to cope with temperature changes, which requires an adequate lipid dynamics. This work provides the lipid profile (galactolipids, GL; phospholipids, PL; sulfolipids, SL) of chloroplast membranes, and the expression of a set of genes related to lipid metabolism in Coffea arabica L. (cv. Icatu and IPR108) and C. canephora cv. Conilon CL153, under elevated [CO2] (380 or 700 μL L−1), heat (25/20, 31/25, 37/30 and 42/34 °C, day/night) and their interaction. Major membrane lipids alterations, different among genotypes, included: A) responsiveness of total fatty acids (TFAs) synthesis to [CO2] (except IPR108) and heat (except CL153); stronger remodeling (unsaturation degree) in the 700-plants from 37/30 °C to 42/34 °C, coordinated at transcriptional level with the down-regulation of fatty acid desaturase FAD3 gene (C. arabica) and up-regulation of lipoxygenase genes LOX5A (CL153 and Icatu) and LOX5B (Icatu) at the highest temperature; B) quantitative and qualitative modifications in GL (monogalactosyldiacylglycerol, MGDG; digalactosyldiacylglycerol, DGDG), PL (phosphatidylcholine, PC; phosphatidylglycerol, PG), and SL (sulfoquinovosyldiacylglycerol, SQDG) classes, prompted by heat, elevated [CO2], and, especially, the interaction, in CL153 and Icatu. Overall membrane enrichment with MGDG and DGDG as a result of heat and [CO2] interaction in these genotypes, but at the highest temperature only in Icatu the high [CO2] maintained greater contents and unsaturation values of these GLs than in the 380-plants. C) Among PL classes, PG seems to play an active role in heat acclimation of C. arabica genotypes, increasing in 700-plants at 42/34 °C. Globally, Icatu often showed changes closer to those of heat tolerant cv. CL153 than to cv. IPR108. Overall, lipid profile adjustments in chloroplast membranes, from TFAs bulk until FA unsaturation within each class, are expected to contribute to long-term acclimation to climate changes in coffee plant

An unexpected heat resilience, and the mitigation of heat impacts by elevated [CO2] were recently reported in Coffea spp. Plants must maintain membrane fluidity and integrity to cope with temperature changes, which requires an adequate lipid dynamics. This work provides the lipid profile (galactolipids, GL; phospholipids, PL; sulfolipids, SL) of chloroplast membranes, and the expression of a set of genes related to lipid metabolism in Coffea arabica L. (cv. Icatu and IPR108) and C. canephora cv. Conilon CL153, under elevated [CO2] (380 or 700 μL L−1), heat (25/20, 31/25, 37/30 and 42/34 °C, day/night) and their interaction. Major membrane lipids alterations, different among genotypes, included: A) responsiveness of total fatty acids (TFAs) synthesis to [CO2] (except IPR108) and heat (except CL153); stronger remodeling (unsaturation degree) in the 700-plants from 37/30 °C to 42/34 °C, coordinated at transcriptional level with the down-regulation of fatty acid desaturase FAD3 gene (C. arabica) and up-regulation of lipoxygenase genes LOX5A (CL153 and Icatu) and LOX5B (Icatu) at the highest temperature; B) quantitative and qualitative modifications in GL (monogalactosyldiacylglycerol, MGDG; digalactosyldiacylglycerol, DGDG), PL (phosphatidylcholine, PC; phosphatidylglycerol, PG), and SL (sulfoquinovosyldiacylglycerol, SQDG) classes, prompted by heat, elevated [CO2], and, especially, the interaction, in CL153 and Icatu. Overall membrane enrichment with MGDG and DGDG as a result of heat and [CO2] interaction in these genotypes, but at the highest temperature only in Icatu the high [CO2] maintained greater contents and unsaturation values of these GLs than in the 380-plants. C) Among PL classes, PG seems to play an active role in heat acclimation of C. arabica genotypes, increasing in 700-plants at 42/34 °C. Globally, Icatu often showed changes closer to those of heat tolerant cv. CL153 than to cv. IPR108. Overall, lipid profile adjustments in chloroplast membranes, from TFAs bulk until FA unsaturation within each class, are expected to contribute to long-term acclimation to climate changes in coffee plant.

Bread wheat (Triticum aestivum) is a major crop worldwide, and it is highly susceptible to heat. In this work, grain production and composition were evaluated in Portuguese T. aestivum germplasm (landraces and commercial varieties), which was subjected to heat after anthesis (grain filling stage). Heat increased the test weight (TW) in Nabão, Grécia and Restauração, indicating an improved flour-yield potential. Mocho de Espiga Branca (MEB) and Transmontano (T94) showed higher thousand-kernel weight (TKW). Gentil Rosso presented increased soluble sugars, which are yeast substrates in the bread-making process. Ardila stood out for its protein increase under heat. Overall SDS was unaffected by higher temperature, but increased in T94, indicating a better dough elasticity for bread-making purposes. Under heat, lipid content was maintained in most genotypes, being endogenous fatty acids (FAs) key players in fresh bread quality. Lipid unsaturation, evaluated through the double bond index (DBI), also remained unaffected in most genotypes, suggesting a lower flour susceptibility to lipoperoxidation. In Grécia, heat promoted a higher abundance of monounsaturated oleic (C18:1) and polyunsaturated linoleic (C18:2) acids, which are essential fatty acids in the human diet. This work highlighted a great variability in most parameters both under control conditions or in response to heat during grain filling. Cluster analysis of traits revealed a lower susceptibility to heat during grain filling in Ardila, Restauração, and Ruivo, in contrast to MEQ, which seems to be more differentially affected at this stage. Characterization and identification of more favorable features under adverse environments may be relevant for agronomic, industrial, or breeding purposes, in view of a better crop adaptation to changing climate and an improved crop sustainability in agricultural systems more prone to heat stress.

Wild rocket downy mildew (DM), caused by oomycete Hyaloperonospora sp., is a widely spread disease reducing crop production and quality. New productive wild rocket varieties resistant to DM are crucial to control disease and ensure high quality leaves. A histological characterization of Hyaloperonospora sp. infection was performed in 11 wild rocket (Diplotaxis tenuifolia) accessions with contrasting DM responses (R, resistant; PR, partially resistant; S, susceptible). Samples of infected cotyledons, first and second leaves of 14-day-old seedlings were collected at 3, 6, 9, 21 and 24 h post-inoculation (hpi) and 7 days post-inoculation (dpi) and stained for appressoria and haustoria observation and tissue necrosis evaluation. Occurrence of appressoria on host surfaces was higher in leaves compared with cotyledons but unrelated with DM resistance response. Haustoria growth in mycelium was delayed in R accessions from 3 hpi, and signs of cell hypersensitivity reaction were observed at 9 hpi. At 24 hpi, necrotic spots limited pathogen growth in resistant accessions, whilst mycelium invaded larger mesophyll areas and produced more haustoria in susceptible ones. At 7 dpi, sporulation was heavy in S, restricted to droplet deposition sites in PR, and did not occur in R hosts. A rapid response of R accessions resulted in slower mycelium growth and longer infection periods. These traits have important agronomic value and should be considered in germplasm selection for breeding programmes aimed at crop protection. A better understanding of the host response to DM infection will allow selection of more suitable wild rocket accessions in future breeding programmes.

The evaluation of the elemental content of moringa leaves and flowers by Energy Dispersive X-Ray Fluorescence Spectrometry revealed that the leaves are a good source of some macro (Ca and K) and micronutrients (Mn) beyond the presence of important polyunsaturated fatty acids (PUFAs), essential in human nutrition. Total soluble sugars prevail in the flowers which may be linked to insect attraction and the pollination process. M. oleifera leaves, flowers and seeds essential oils (EOs) were isolated by hydrodistillation. Gas chromatography and gas chromatography-mass spectrometry analysis (GC-MS) showed EOs dominated by alkanes and fatty acids in diverse ratios in the analyzed plant parts. The nutritional characterization of M. oleifera cultivated in Portugal showed some important nutrients to human physiology. Further studies will allow determining if its consumption may overcome the nutritional imbalances of daily modern households, preventing the emergence of hypertension and diabetes.

Cowpea (Vigna unguiculata) is a robust legume; nevertheless, yield is always affected by drought, especially when it occurs during reproductive growth and seed filling. Considered a key crop in the effort to attain food security, and a suitable crop for a scenario of climate change, modern disregard for cowpea landraces is particularly detrimental as it causes genetic variability loss, compromising breeding efforts. To contribute to the evaluation of the cowpea germplasm, four Portuguese landraces (L1, L2, L3, L4) were compared with a commercial variety (CV) to evaluate their physiological responses to terminal drought and their inter-variation on productivity, under semi-controlled conditions. Despite no differences in relative water content (RWC) between the CV and the landraces under water deficit (WD), differences in leaf water potential (Ψ) defined the CV as having an isohydric control of stomata in contrast with anisohydric control for landraces. There was an identical decrease in the photosynthetic rate for all plants under stress, caused by both stomatal and non-stomatal limitations, namely, damages at the level of photosystem II as indicated by fluorescence measurements. Instantaneous water use efficiency (iWUE) was improved with stress in L1 and L3. Maintenance of higher relative chlorophyll content for longer periods in the CV revealed a stay-green phenotype. The slim differences observed in terms of stomatal control, iWUE and progression of senescence between the CV and the landraces under WD led to quite important differences in terms of productivity, as inferred from improved yield (number of pods and number of grains per plant). This is a clear result of pragmatic on-farm selection. On one hand it shows that small differences in stomatal responses or water saving strategies under WD may lead to desirable outcomes and should therefore be considered during breeding. On the other hand, it suggests that other traits could be explored in view of drought adaptation. These results highlight the need to preserve and characterize as many genetic pools as possible within a species.

The relative agronomic performance of two organic fertilizers - effluents from intensive cattle farming, after composting either by traditional aerobic methods (compost) or by bio-digestion by larvae of the black soldier fly (Hermetia illucens, BSF) (frass) - in the growth of annual ryegrass (Lolium multiflorum L.) on a sandy soil was evaluated. For this purpose, a pot trial was conducted in a semi-controlled greenhouse. Eight treatments were defined, with four treatments using the compost and four treatments using frass (with a 10% nitroamoniacal nitrogen supplementation in all treatments), in addition to a negative control without fertilization, and a positive control with exclusively chemical nitroamoniacal fertilization. Regarding the biomass production, the BSF frass displayed a higher potential than the compost, with a significantly higher production from an N endowment equivalent to 280 kg ha-1 (252 kg organic N + 28 kg mineral N). While the yields obtained with compost were stable when 350 kg ha-1 (315 kg organic N + 35 kg mineral N) were provided, the yields obtained with BSF frass revealed a tendency to continue to progress with higher doses. This could be justified by the fact that the P2O5 and K2O content of BSF frass is significantly higher than that of the compost, and these nutrients continued to be mineralized over time. Furthermore, the obtained results confirm the potentiating effect of mineral fertilizers in the maximization of biomass production, when associated with organic fertilizers in adequate proportions. In addition, it was verified that the addition of frass enhanced the water use by plants, which was significantly higher than the treatments with compost, regardless of the N endowment. It was concluded that mixing chemical and organic fertilizers positively impacts soil fertility and the sustainability of the production as a whole, by increasing productivities in a sustainable way.

Waterlogging at the tillering stage, a key early vegetative growth stage, is increasingly limiting wheat productivity worldwide, but the physiological mechanisms underlying genotypic tolerance are not fully understood. To address this, 23 bread wheat (Triticum aestivum L.) genotypes from five germplasm groups were exposed to 14 days of waterlogging at the tillering stage. Morphological traits including leaf (green area, biomass, and senescent biomass proportion) and the elongation rate of the main culm (cm day−1), plant water status (relative water content, RWC), photosynthetic pigment content (SPAD values; total chlorophyll, TChl; total carotenoids, TCar), and photosynthetic performance (maximal photochemical efficiency of photosystem II, Fv/Fm; actual photochemical efficiency of photosystem II, Fv′/Fm′; net photosyntheis, Pn; stomatal conductance to water vapor, gs), were assessed. Waterlogging induced strong but highly variable responses among genotypes. Sensitive genotypes showed marked reductions in green biomass (up to ~40–60%), TChl content (up to ~80%), TCar (~70%), and photosynthetic performance, including declines in Fv/Fm, Fv′/Fm′, and Pn. In contrast, tolerant genotypes maintained higher photochemical efficiency, Pn, and pigment content, despite stress exposure, underscoring greater functional resilience. Importantly, morphological stability did not consistently translate into functional performance. Several genotypes maintained green leaf area despite pronounced declines in photosynthetic capacity and pigment content, revealing a decoupling between morphological and physiological responses. Multivariate analysis identified an integrated photosynthetic trait axis strongly associated with yield performance under stress, highlighting that tolerance is primarily driven by the capacity to maintain photosynthetic function rather than green biomass alone. Together, these findings emphasize the importance of preserving both physiological functionality and green leaf area to maintain waterlogging tolerance. Integrated physiological markers (e.g., TChl and TCar content, photochemical quenching, leaf gas exchange traits) enable effective early screening and support function-based selection in wheat breeding programs.

Inundation, excessive precipitation, or inadequate field drainage can cause waterlogging of cultivated land. It is anticipated that climate change will increase the frequency, intensity, and unpredictability of flooding events. This stress affects 10–15 million hectares of wheat every year, resulting in 20–50% yield losses. Since this crop greatly sustains a population’s food demands, providing ca. 20% of the world’s energy and protein diets requirements, it is crucial to understand changes in soil and plant physiology under excess water conditions. Variations in redox potential, pH, nutrient availability, and electrical conductivity of waterlogged soil will be addressed, as well as their impacts in major plant responses, such as root system and plant development. Waterlogging effects at the leaf level will also be addressed, with a particular focus on gas exchanges, photosynthetic pigments, soluble sugars, membrane integrity, lipids, and oxidative stress.

Metamitron (MET) is a fruitlet thinning compound for apple trees, needing better understanding of its action on leaf energy metabolism, depending on nighttime temperature. A trial under environmental controlled conditions was set with ‘Golden Reinders’ potted trees, under 25/7.5 and 25/15 ◦C (diurnal/nighttime temperature), with (MET, 247.5 ppm) or without (CTR) application, and considering the monitoring of photosynthetic and respiration components from day 1 (D1) to 14 (D14). Net photosynthesis (Pn) decline promoted by MET after D1 was not stomatal related. Instead, non-stomatal constraints, reflected on the photosynthetic capacity (Amax), included a clear photosystem (PS) II inhibition (but barely of PSI), as shown by severe reductions in thylakoid electron transport at PSII level, maximal (Fv/Fm) and actual (Fv’/Fm’) PSII photochemical efficiencies, estimate of quantum yield of linear electron transport (Y(II)), and the rise in PSII photoinhibition status (Fs/Fm’ and PIChr) and uncontrolled energy dissipation (Y(NO)). To Pn inhibition also contributed the impact in RuBisCO along the entire experiment, regardless of night temperature, here reported for the first time. Globally, MET impact on the photosynthetic parameters was usually greater under 7.5 ◦C, with maximal impacts between D4 and D7, probably associated to a less active metabolism at lower temperature. Cellular energy metabolism was further impaired under 7.5 ◦C, through moderate inhibition of NADH-dependent malate dehydrogenase (MDH) and pyruvate kinase (PK) enzymes involved in respiration, in contrast with the increase of dark respiration in MET 7.5 until D7. The lower impact on PK and MDH under 15 ◦C and a likely global higher active metabolism at that temperature would agree with the lowest sucrose levels in MET 15 at D4 and D7. Our findings showed that MET alters the cell energy machinery in a temperature dependent manner, affecting the sucrose balance mainly at 15 ◦C, justifying the observed greater thinning potential