Food talk: 40-Hz fin whale calls are associated with prey biomass.

Animals use varied acoustic signals that play critical roles in their lives. Understanding the function of these signals may inform about key life-history processes relevant for conservation. In the case of fin whales (Balaenoptera physalus), that produce different call types associated with different behaviours, several hypotheses have emerged regarding call function, but the topic still remains in its infancy. Here, we investigate the potential function of two fin whale vocalizations, the song-forming 20-Hz call and the 40-Hz call, by examining their production in relation to season, year and prey biomass. Our results showed that the production of 20-Hz calls was strongly influenced by season, with a clear peak during the breeding months, and secondarily by year, likely due to changes in whale abundance. These results support the reproductive function of the 20-Hz song used as an acoustic display. Conversely, season and year had no effect on variation in 40-Hz calling rates, but prey biomass did. This is the first study linking 40-Hz call activity to prey biomass, supporting the previously suggested food-associated function of this call. Understanding the functions of animal signals can help identifying functional habitats and predict the negative effects of human activities with important implications for conservation.

Growth and resilience responses of Scots pine to extreme droughts across Europe depend on predrought growth conditions.

Global climate change is expected to further raise the frequency and severity of extreme events, such as droughts. The effects of extreme droughts on trees are difficult to disentangle given the inherent complexity of drought events (frequency, severity, duration, and timing during the growing season). Besides, drought effects might be modulated by trees' phenotypic variability, which is, in turn, affected by long-term local selective pressures and management legacies. Here we investigated the magnitude and the temporal changes of tree-level resilience (i.e., resistance, recovery, and resilience) to extreme droughts. Moreover, we assessed the tree-, site-, and drought-related factors and their interactions driving the tree-level resilience to extreme droughts. We used a tree-ring network of the widely distributed Scots pine (Pinus sylvestris) along a 2,800 km latitudinal gradient from southern Spain to northern Germany. We found that the resilience to extreme drought decreased in mid-elevation and low productivity sites from 1980-1999 to 2000-2011 likely due to more frequent and severe droughts in the later period. Our study showed that the impact of drought on tree-level resilience was not dependent on its latitudinal location, but rather on the type of sites trees were growing at and on their growth performances (i.e., magnitude and variability of growth) during the predrought period. We found significant interactive effects between drought duration and tree growth prior to drought, suggesting that Scots pine trees with higher magnitude and variability of growth in the long term are more vulnerable to long and severe droughts. Moreover, our results indicate that Scots pine trees that experienced more frequent droughts over the long-term were less resistant to extreme droughts. We, therefore, conclude that the physiological resilience to extreme droughts might be constrained by their growth prior to drought, and that more frequent and longer drought periods may overstrain their potential for acclimation.

On the use of the Lloyd's Mirror effect to infer the depth of vocalizing fin whales.

The interference between the direct path and the sea surface reflection of a signal as measured by a receiver is called Lloyd's Mirror effect (LME). It results in a frequency-dependent interference pattern that can be observed in a spectrogram. LME depends on the receiver depth, signal source depth, signal frequency, and slant range between source and receiver. Knowing three of these parameters a priori, LME can be used to estimate the third parameter, such as source depth. Here, the work in Pereira et al. (2016) was expanded to estimate the depth of a vocalizing fin whale recorded by an ocean-bottom seismometer (OBS). In Pereira et al. (2016), the depth of a vocalizing fin whale was inferred by manually comparing spectrograms of LME transmission loss models with observed LME. This study developed an automated procedure to perform the same task using the LME interference pattern observed in the spectrograms of the hydrophone and the vertical channel of the OBS. The results show that the joint use of the two channels was the best approach to estimate a source depth using LME. LME provides a non-intrusive approach for estimating the depth at which a fin whale was vocalizing.

Fin whale acoustic presence and song characteristics in seas to the southwest of Portugal.

Fin whales were once abundant in the seas to the southwest of Portugal, but whaling activities decreased their numbers considerably. Acoustic data from ocean bottom seismometers provide an opportunity to detect fin whales from their notes, data that would otherwise be logistically challenging and expensive to obtain. Based on inter-note interval and frequency bandwidth, two acoustic patterns produced by fin whales were detected in the study area: pattern 1, described from fin whales in the Mediterranean Sea, and pattern 2, associated with fin whales from the northeast North Atlantic Ocean (NENA). NENA fin whales travel into the western Mediterranean Sea, but the Mediterranean population has not been documented to travel regularly into the NENA. In this study, 11 months of acoustic data recorded southwest of Portugal in the NENA were used to characterize 20-Hz fin whale notes into these patterns. Pattern 2 was the most common and occurred mostly in November-January. Pattern 1 occurred less frequently and mostly in September-December, February and April, which suggested a limited excursion of whales from the Mediterranean Sea. There were also occasions when the two patterns were recorded simultaneously. Results suggest that fin whales from the NENA and Mediterranean Sea might mix in the area during part of the year.

Identification of an Argentinean isolate of Spodoptera frugiperda granulovirus.

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is an important maize pest. Due to the environmental impact and emergence of resistance caused by chemical pesticides and transgenic events, the use of baculoviruses becomes a safe and useful alternative for its control in integrated pest management strategies. Here we report the identification of a novel isolate of a granulovirus of S. frugiperda native to the central region of Argentina, named SfGV ARG. We observed that larvae infected with SfGV ARG showed a yellowish coloration, swollen body and, in some cases, severe lesions in the last abdominal segments. We confirmed the identity of the isolate by sequencing fragments of the lef-8, lef-9 and granulin genes and by calculating evolutionary distances using the Kimura-2-Parameter model. SfGV ARG DNA restriction pattern allowed to estimate a genome of at least 135 kb.

The "isohydric trap": A proposed feedback between water shortage, stomatal regulation, and nutrient acquisition drives differential growth and survival of European pines under climatic dryness.

Climatic dryness imposes limitations on vascular plant growth by reducing stomatal conductance, thereby decreasing CO2 uptake and transpiration. Given that transpiration-driven water flow is required for nutrient uptake, climatic stress-induced nutrient deficit could be a key mechanism for decreased plant performance under prolonged drought. We propose the existence of an "isohydric trap," a dryness-induced detrimental feedback leading to nutrient deficit and stoichiometry imbalance in strict isohydric species. We tested this framework in a common garden experiment with 840 individuals of four ecologically contrasting European pines (Pinus halepensis, P. nigra, P. sylvestris, and P. uncinata) at a site with high temperature and low soil water availability. We measured growth, survival, photochemical efficiency, stem water potentials, leaf isotopic composition (δ13 C, δ18 O), and nutrient concentrations (C, N, P, K, Zn, Cu). After 2 years, the Mediterranean species Pinus halepensis showed lower δ18 O and higher δ13 C values than the other species, indicating higher time-integrated transpiration and water-use efficiency (WUE), along with lower predawn and midday water potentials, higher photochemical efficiency, higher leaf P, and K concentrations, more balanced N:P and N:K ratios, and much greater dry-biomass (up to 63-fold) and survival (100%). Conversely, the more mesic mountain pine species showed higher leaf δ18 O and lower δ13 C, indicating lower transpiration and WUE, higher water potentials, severe P and K deficiencies and N:P and N:K imbalances, and poorer photochemical efficiency, growth, and survival. These results support our hypothesis that vascular plant species with tight stomatal regulation of transpiration can become trapped in a feedback cycle of nutrient deficit and imbalance that exacerbates the detrimental impacts of climatic dryness on performance. This overlooked feedback mechanism may hamper the ability of isohydric species to respond to ongoing global change, by aggravating the interactive impacts of stoichiometric imbalance and water stress caused by anthropogenic N deposition and hotter droughts, respectively.

Multi-cropping edible truffles and sweet chestnuts: production of high-quality Castanea sativa seedlings inoculated with Tuber aestivum, its ecotype T. uncinatum, T. brumale, and T. macrosporum.

The plantation and management of sweet chestnut (Castanea sativa Mill.) orchards is a common and traditional land use system in many areas of Europe that offers the advantage of simultaneous production of nuts and timber. During the last decades, sweet chestnut has declined dramatically in many regions because of the profound social changes in rural areas coupled with pathogen attacks. Truffles, the hypogeous ascocarps of the ectomycorrhizal genus Tuber, are currently cultivated using host trees inoculated with these fungi for improving production in truffle orchards. The production of good forestry quality chestnut seedlings inoculated with European truffles in nurseries is essential for multi-cropping plantation establishment, but so far, it has not been implemented in agroforestry practices. Moreover, it is necessary to assess the physiological condition of the seedlings due to the high calcium amendment needed for the growth of Tuber spp. mycelium that can become toxic for the host plants. In this study, seedlings of C. sativa were inoculated with Tuber aestivum and its ecotypes T. uncinatum, T. brumale, and T. macrosporum and were grown in a greenhouse using culture conditions favorable for the production of high-quality plants for forestry purposes. At the end of the assay, levels of root colonization and morphological and physiological parameters of the seedlings were measured. The colonization of C. sativa with T. aestivum, its ecotype T. uncinatum, and T. brumale was successful, and the seedlings showed normal growth. Inoculation protocols with T. macrosporum need to be improved. Tuber species formed well-developed ectomycorrhizae on C. sativa in nursery conditions.

Contrasting growth forecasts across the geographical range of Scots pine due to altitudinal and latitudinal differences in climatic sensitivity.

Ongoing changes in global climate are altering ecological conditions for many species. The consequences of such changes are typically most evident at the edge of a species' geographical distribution, where differences in growth or population dynamics may result in range expansions or contractions. Understanding population responses to different climatic drivers along wide latitudinal and altitudinal gradients is necessary in order to gain a better understanding of plant responses to ongoing increases in global temperature and drought severity. We selected Scots pine (Pinus sylvestris L.) as a model species to explore growth responses to climatic variability (seasonal temperature and precipitation) over the last century through dendrochronological methods. We developed linear models based on age, climate and previous growth to forecast growth trends up to year 2100 using climatic predictions. Populations were located at the treeline across a latitudinal gradient covering the northern, central and southernmost populations and across an altitudinal gradient at the southern edge of the distribution (treeline, medium and lower elevations). Radial growth was maximal at medium altitude and treeline of the southernmost populations. Temperature was the main factor controlling growth variability along the gradients, although the timing and strength of climatic variables affecting growth shifted with latitude and altitude. Predictive models forecast a general increase in Scots pine growth at treeline across the latitudinal distribution, with southern populations increasing growth up to year 2050, when it stabilizes. The highest responsiveness appeared at central latitude, and moderate growth increase is projected at the northern limit. Contrastingly, the model forecasted growth declines at lowland-southern populations, suggesting an upslope range displacement over the coming decades. Our results give insight into the geographical responses of tree species to climate change and demonstrate the importance of incorporating biogeographical variability into predictive models for an accurate prediction of species dynamics as climate changes.

Asymmetric changes of growth and reproductive investment herald altitudinal and latitudinal range shifts of two woody species.

Ongoing changes in global climate are altering ecological conditions for many species. The consequences of such changes are typically most evident at the edge of the geographical distribution of a species, where range expansions or contractions may occur. Current demographical status at geographical range limits can help us to predict population trends and their implications for the future distribution of the species. Thus, understanding the comparability of demographical patterns occurring along both altitudinal and latitudinal gradients would be highly informative. In this study, we analyse the differences in the demography of two woody species through altitudinal gradients at their southernmost distribution limit and the consistency of demographical patterns at the treeline across a latitudinal gradient covering the complete distribution range. We focus on Pinus sylvestris and Juniperus communis, assessing their demographical structure (density, age and mortality rate), growth, reproduction investment and damage from herbivory on 53 populations covering the upper, central and lower altitudes as well as the treeline at central latitude and northernmost and southernmost latitudinal distribution limits. For both species, populations at the lowermost altitude presented older age structure, higher mortality, decreased growth and lower reproduction when compared to the upper limit, indicating higher fitness at the treeline. This trend at the treeline was generally maintained through the latitudinal gradient, but with a decreased growth at the northern edge for both species and lower reproduction for P. sylvestris. However, altitudinal and latitudinal transects are not directly comparable as factors other than climate, including herbivore pressure or human management, must be taken into account if we are to understand how to infer latitudinal processes from altitudinal data.

A single-station method for the detection, classification and location of fin whale calls using ocean-bottom seismic stations.

Passive seismic monitoring in the oceans uses long-term deployments of Ocean Bottom Seismometers (OBSs). An OBS usually records the three components of ground motion and pressure, typically at 100 Hz. This makes the OBS an ideal tool to investigate fin and blue whales that vocalize at frequencies below 45 Hz. Previous applications of OBS data to locate whale calls have relied on single channel analyses that disregard the information that is conveyed by the horizontal seismic channels. Recently, Harris, Matias, Thomas, Harwood, and Geissler [J. Acoust. Soc. Am. 134, 3522-3535 (2013)] presented a method that used all four channels recorded by one OBS to derive the range and azimuth of fin whale calls. In this work, the detection, classification, and ranging of calls using this four-channel method were further investigated, focusing on methods to increase the accuracy of range estimates to direct path arrivals. Corrections to account for the influences of the sound speed in the water layer and the velocity structure in the top strata of the seabed were considered. The single station method discussed here is best implemented when OBSs have been deployed in deep water on top of seabed strata with low P-wave velocity. These conditions maximize the ability to detect and estimate ranges to fin whale calls.

Impacts of predicted climate change on recruitment at the geographical limits of Scots pine.

Ongoing changes in global climate are having a significant impact on the distribution of plant species, with effects particularly evident at range limits. We assessed the capacity of Pinus sylvestris L. populations at northernmost and southernmost limits of the distribution to cope with projected changes in climate. We investigated responses including seed germination and early seedling growth and survival, using seeds from northernmost (Kevo, Finland) and southernmost (Granada, Spain) populations. Seeds were grown under current climate conditions in each area and under temperatures increased by 5 °C, with changes in precipitation of +30% or -30% with reference to current values at northern and southern limits, respectively, in a fully factorial controlled-conditions experimental design. Increased temperatures reduced germination time and enhanced biomass gain at both range edges but reduced survival at the southern range edge. Higher precipitation also increased survival and biomass but only under a southern climate. Seeds from the southern origin emerged faster, produced bigger seedlings, allocated higher biomass to roots, and survived better than northern ones. These results indicate that recruitment will be reduced at the southernmost range of the species, whereas it will be enhanced at the northern limit, and that the southern seed sources are better adapted to survive under drier conditions. However, future climate will impose a trade-off between seedling growth and survival probabilities. At the southern range edge, higher growth may render individuals more susceptible to mortality where greater aboveground biomass results in greater water loss through evapotranspiration.

Acoustic imaging of stable double diffusion in the Madeira abyssal plain.

Sub-mesoscale and mesoscale (i.e., 1-10 km and 10-200 km, respectively) ocean processes are highly relevant for the understanding of global circulation, mixing of water masses and energy exchange between ocean layers. However, the processes happening at these scales are hard to be characterized using direct measurements of temperature and salinity. Direct measurements are obtained from vertical probes and/or autonomous vehicles, which, despite their high vertical resolution, are sparsely located in space and therefore unable to capture spatial details at these scales. Seismic oceanography (SO) data have been successfully used to imaging and characterize the ocean at these spatial scales. These data represent indirect measurements of the ocean temperature and salinity along kilometric transects with high horizontal resolution (i.e., a near-synaptic view of the system under investigation), but lower vertical resolution when compared with direct observations. Despite its complex oceanographic setting, the Madeira Abyssal Plain is still largely uncharacterized due to the lack of direct observations. We show for the first time a comprehensive processing, modelling and interpretation of three 2-D seismic oceanography sections from this region. The data show coherent seismic reflection in space, depth and time and shed light into this oceanographic setting with an unprecedent horizontal resolution. The SO modelling and interpretation are combined with existing direct measurements and a quantitative method to correlate thermohaline staircases interpreted from conductivity-temperature-depth casts and seismic reflections is proposed. The results show the relatively stable presence of thermohaline staircases in simultaneously time and space between 1200 and 2000 m of water depth and their spatial variability and contribute to the generalization of SO in physical oceanography.

Climatic drivers of cork growth depend on site aridity.

Cork is one of the main non-timber forest products in the world. Most of its production is concentrated in the Iberian Peninsula, a climate change hotspot. Climate warming may lead to increased aridification and reduce cork production in that region. However, we still lack assessments of climate-cork relationships across ample geographical and climatic gradients explicitly considering site aridity. We quantified cork growth by measuring cork ring width and related it to climate variables and a drought index using dendrochronology. Four cork oak (Quercus suber) forests located from north eastern Spain to south western Morocco (31.5-41.5° N) and subjected to different aridity levels were sampled. Warm conditions in spring to early summer, when cork is formed, reduced cork width, whereas high precipitation in winter and spring enhanced it. The response of cork to increased water availability in summer peaked (r = 0.89, p = 0.00002) in the most arid and continental site considering 14-month long droughts. A severe drought caused a disproportionate loss of cork production in this site, where for every five-fold decrease in the drought index, the cork-width index declined by a factor of thirteen. Therefore, site aridity determines the responses of cork growth to the soil water availability resulting from accumulated precipitation during winter and spring previous to cork growth and until summer. In general, this cumulative water balance, which is very dependent on temperature and evapotranspiration rate, is critical for cork production, especially in continental, dry sites. The precipitation during the hydrological year can be used as a proxy of cork production in similar sites. Assessments of climate-cork relationships in the western Mediterranean basin could be used as analogues to forecast the impacts of aridification on future cork production.

Management of pediatric pial arteriovenous fistulas with a single connection: two illustrative cases.

Pediatric arteriovenous fistulas (PAVFs) are rare, representing only 7.3-17.2% of all pediatric shunts.1 2 In a number of cases they can lead to life-threatening venous hypertension, hydrocephalus and macrocrania,3 heart failure,1 hemorrhagic stroke,4 5 seizures,3 and cognitive developmental issues.1-3 In selected circumstances, early and aggressive treatment is recommended.We present two cases of single-connection, high-flow PAVFs. Case 1 represents a mid-basilar PAVF treated through a transarterial approach, while case 2 represents a quadrigeminal cistern PAVF treated with several transarterial sessions followed by a final transvenous session. The procedures are shown in video 1neurintsurg;jnis-2024-021955v1/V1F1V1Video 1 Clinical cases demonstrating endovascular treatment of pediatric pial arteriovenous fistulas.

Fin whale song evolution in the North Atlantic.

Animal songs can change within and between populations as the result of different evolutionary processes. When these processes include cultural transmission, the social learning of information or behaviours from conspecifics, songs can undergo rapid evolutions because cultural novelties can emerge more frequently than genetic mutations. Understanding these song variations over large temporal and spatial scales can provide insights into the patterns, drivers and limits of song evolution that can ultimately inform on the species' capacity to adapt to rapidly changing acoustic environments. Here, we analysed changes in fin whale (Balaenoptera physalus) songs recorded over two decades across the central and eastern North Atlantic Ocean. We document a rapid replacement of song INIs (inter-note intervals) over just four singing seasons, that co-occurred with hybrid songs (with both INIs), and a clear geographic gradient in the occurrence of different song INIs during the transition period. We also found gradual changes in INIs and note frequencies over more than a decade with fin whales adopting song changes. These results provide evidence of vocal learning in fin whales and reveal patterns of song evolution that raise questions on the limits of song variation in this species.

Silica-coated magnetic particles for efficient RNA extraction for SARS-CoV-2 detection.

Molecular diagnostic methods to detect and quantify viral RNA in clinical samples rely on the purification of the genetic material prior to reverse transcription polymerase chain reaction (qRT-PCR). Due to the large number of samples processed in clinical laboratories, automation has become a necessity in order to increase method processivity and maximize throughput per unit of time. An attractive option for isolating viral RNA is based on the magnetic solid phase separation procedure (MSPS) using magnetic microparticles. This method offers the advantage over other alternative methods of making it possible to automate the process. In this study, we report the results of the MSPS method based on magnetic microparticles obtained by a simple synthesis process, to purify RNA from oro- and nasopharyngeal swab samples of patients suspected of COVID-19 provided by three diagnostic laboratories located in the Buenos Aires Province, Argentina. Magnetite nanoparticles of Fe3O4 (MNPs) were synthesized by the coprecipitation method and then coated with silica (SiO2) produced by hydrolysis of tetraethyl orthosilicate (TEOS). After preliminary tests on samples from the A549 human lung cell line and swabs, an extraction protocol was developed. The quantity and purity of the RNA obtained were determined by gel electrophoresis, spectrophotometry, and qRT-PCR. Tests on samples from naso- and oropharyngeal swabs were performed in order to validate the method for RNA purification in high-throughput SARS-CoV-2 diagnosis by qRT-PCR. The method was compared to the spin columns method and the automated method using commercial magnetic particles. The results show that the method developed is efficient for RNA extraction from nasal and oropharyngeal swab samples, and also comparable to other extraction methods in terms of sensitivity for SARS-CoV-2 detection. Of note, this procedure and reagents developed locally were intended to overcome the shortage of imported diagnostic supplies as the sudden spread of COVID-19 required unexpected quantities of nucleic acid isolation and diagnostic kits worldwide.

Applying distance sampling to fin whale calls recorded by single seismic instruments in the northeast Atlantic.

Automated methods were developed to detect fin whale calls recorded by an array of ocean bottom seismometers (OBSs) deployed off the Portuguese coast between 2007 and 2008. Using recordings collected on a single day in January 2008, a standard seismological method for estimating earthquake location from single instruments, the three-component analysis, was used to estimate the relative azimuth, incidence angle, and horizontal range between each OBS and detected calls. A validation study using airgun shots, performed prior to the call analysis, indicated that the accuracy of the three-component analysis was satisfactory for this preliminary study. Point transect sampling using cue counts, a form of distance sampling, was then used to estimate the average probability of detecting a call via the array during the chosen day. This is a key step to estimating density or abundance of animals using passive acoustic data. The average probability of detection was estimated to be 0.313 (standard error: 0.033). However, fin whale density could not be estimated due to a lack of an appropriate estimate of cue (i.e., vocalization) rate. This study demonstrates the potential for using a sparse array of widely spaced, independently operating acoustic sensors, such as OBSs, for estimating cetacean density.

A data set of earthquake bulletin and seismic waveforms for Ghana obtained by deep learning.

The Ghana Digital Seismic Network (GHDSN) data, with six broadband sensors, operating in southern Ghana for two years (2012-2014). The recorded dataset is processed for simultaneous event detection and phase picking by a Deep Learning (DL) model, the EQTransformer tool. Here, the detected earthquakes consisting of supporting data, waveforms (including P and S arrival phases), and earthquake bulletin are presented. The bulletin includes the 559 arrival times (292 P and 267 S phases) and waveforms of the 73 local earthquakes in SEISAN format. The supporting data encompasses the preliminary crustal velocity models obtained from the joint inversion analysis of the detected hypocentral parameters. These parameters comprised of a 6- layer model of the crustal velocity (Vp and Vp/Vs ratio), incident time sequence, and statistical analysis of the detected earthquakes and hypocentral parameters analyzed and relocated by the updated crustal velocity and graphic representation of them a 3D live figure enlighting the seismogenic depth of the region. This dataset has a unique appeal for earth science specialists to analyze and reprocess the detected waveforms and characterize the seismogenic sources and active faults in Ghana. The metadata and waveforms have been deposited at the Mendeley Data repository [1].

Latitudinal variation in the functional response of Quercus suber seedlings to extreme drought.

Many plant species are being threatened by increasingly drought conditions due to current climate change at planetary scale. This global trend is leading to the scientific community to investigate the potential role of local adaptations through intraspecific differences in functional traits that may boost conservation strategies by modulating the plant responses to reduced water availability. We assessed under controlled conditions the effect of four different drought intensities on the survival time and morphological traits of Quercus suber seedlings collected from nine populations covering the complete latitudinal distribution of the species. Functional morphological traits related to biomass allocation and leaf and root display were analyzed. We then related these traits with the survival time after a terminal desiccation, used as a drought-resistance proxy and expressed as survival time without watering. Abundant watering availability allowed seedlings to survive for a longer period compared to drier conditions. Further, all morphological traits differed across watering levels, showing a very plastic response. Acorns from southern latitudes produced very large seedlings compared to those gathered from northern latitudes. However, the larger biomass implied higher evaporative water loss, inducing lower survival of southern populations under extreme drought conditions. We further found a clear trend toward maximizing those traits related with belowground growth (i.e., root surface area, root average diameter and root volume) in southern populations aimed to increase water uptake, overcoming the most limiting factor for plant growth in that area. Our results support that increased root development allow cork oak to maintain its functioning after being subjected to damage caused by reduced water availability, whereas high aerial biomass allocation is a handicap for survival under drought stress conditions. This study identifies drought-resistant populations and morphological traits related to drought resistance, which can be applied to improve restoration actions under a warmer climate.

Soil physicochemical properties associated with the yield and phytochemical composition of the edible halophyte Crithmum maritimum.

There is growing interest in the consumption of halophytes due to their excellent nutritional profile and antioxidant properties, and their cultivation offers viable alternatives in the face of irreversible global salinization of soils. Nevertheless, abiotic factors strongly influence their phytochemical composition, and little is known about how growing conditions can produce plants with the best nutritional and functional properties. Crithmum maritimum is an edible halophyte with antioxidant properties and considerable potential for sustainable agriculture in marginal environments. However, it is found naturally in contrasting habitats with variable soil physicochemical properties and the extent to which edaphic factors can influence plant performance, accumulation of phytochemicals and their quality remains unknown. We investigated the influence of soil physicochemical properties (texture, pH, electrical conductivity, organic matter content and mineral element concentrations) on growth and reproductive performance, nutritional traits, and the accumulation of specific metabolites in C. maritimum. Soil, leaf and seed samples were taken from eight C. maritimum populations located on the southern coasts of Spain and Portugal. We found greater vegetative growth and seed production in coarser, sandier soils with lower microelement concentrations. The nutritional traits of leaves varied, with soil organic matter and macronutrient content associated with reduced leaf Na, protein and phenolic (mainly flavonoid) concentrations, whereas soils with lower pH and Fe concentrations, and higher clay content yielded plants with lower leaf Zn concentration and greater accumulation of hydroxycinnamic acids. The nutritional value of the seed oil composition appeared to be enhanced in soils with coarser texture and lower microelement concentrations. The accumulation of specific phenolic compounds in the seed was influenced by a wide range of soil properties including texture, pH and some microelements. These findings will inform the commercial cultivation of C. maritimum, particularly in the economic exploitation of poorly utilized, saline soils.