Effects of Cultivation System and Fertilization on Seedling Production of Ocimum basilicum L. and Mentha spicata L.

The demand for aromatic plants as ornamentals and sources of essential oils has increased recently. A float system is a promising alternative method of seedling production. Two cropping systems, float and conventional (seed bed), and two nutrient solution formulations, one organic and one inorganic, were evaluated for Ocimum basilicum (basil) and Mentha spicata (spearmint) seedling production. Basil seedlings grown in float system had better or comparable growth of shoots and leaves with those grown in seedbeds, irrespective of the fertilization, whereas spearmint organic fertilization reduced the growth of the aboveground parts of the seedlings, regardless of the cropping system. By contrast, fertilization treatments on both species' seedling grown in float system showed better root length and higher root biomass accumulation. The survival percentage of seedlings after transplanting, as well as the subsequent growth of plants, were not seriously affected by the cropping system of the fertilization method during transplant production. Overall, we conclude that a float system can be used for the production of Ocimum basilicum and Mentha spicata seedlings under organic or inorganic fertilization

Cultivar-Dependent Responses of Eggplant (Solanum melongena L.) to Simultaneous Verticillium dahliae Infection and Drought

Several studies regarding the imposition of stresses simultaneously in plants have shown that plant responses are different under individual and combined stress. Pathogen infection in combination with drought can act both additively and antagonistically, suggesting a tailored-made plant response to these stresses. The aforementioned combination of stresses can be considered as one of the most important factors affecting global crop production. In the present research we studied eggplant responses to simultaneous Verticillium dahliae infection and drought with respect to the application of the individual stresses alone and investigated the extent to which these responses were cultivar dependent. Two eggplant cultivars (Skoutari and EMI) with intermediate resistance to V. dahliae were subjected to combined stress for a 3-week period. Significant differences in plant growth, several physiological and biochemical parameters (photosynthesis rate, leaf gas exchanges, Malondialdehyde, Proline) and gene expression, were found between plants subjected to combined and individual stresses. Furthermore, plant growth and molecular (lipid peroxidation, hydrogen peroxide, gene expression levels) changes highlight a clear discrimination between the two cultivars in response to simultaneous V. dahliae infection and drought. Our results showed that combined stress affects significantly plants responses compared to the application of individual stresses alone and that these responses are cultivar dependent

Study of factors that influence microsporogenesis in greenhouse tomato (Lycopersicon esculentum Mill.)

The ultimate aim of this study, was to investigate the effects of climatic factors (especially extreme temperatures and the level of solar radiation), on the seasonal production and viability of tomato pollen throughout the cultivation period (October-July) within the greenhouse, which is in turn closely correlated with the productivity of the tomato crop, particularly under adverse climatic conditions. The estimation of pollen viability was based on in vitro germination on semi-solid (with agar) substrates. Because of the lack of a standard semi-solid medium for the in vitro germination of tomato pollen, an attempt was made to define the effects of several physical (incubation temperature, pH of the medium) and chemical factors on the in vitro germinability of tomato pollen on semi-solid, agar-based media. The addition of various chemical compounds (plant growth regulators, amino acids, vitamins, flavonoids) did not prove essential for tomato pollen germination. However, partial substitution of sucrose by PEG-6000 (but not by mannitol), as well as the inclusion of the flavonoids quercetin and myricetin (at 5 mg 1⁻¹) within the medium, significantly increased the germinability of tomato pollen, which was also favoured by an incubation temperature of 15°C and medium pH of 6.5. In addition, the type and purity of the gelling agent used in semi-solid substrates, significantly affected the in vitro germinability and tube length of tomato pollen on semi-solid media. Although gelling agents of high purity (e.g. washed agar or agarose) did not satisfactorily supply germinating tomato pollen with the essential ions K, Mg and Ca, gelling agents of a higher inherent ion content reduced pollen germination, possibly because of the presence of germination inhibitors. Washing low purity agars with distilled water increased their efficacy, by removing part of their ion content. Since Ca concentrations higher than 3mM in the semi-solid medium impair tomato pollen germination, the effectiveness of the addition of K, Mg and Ca according to Brewbaker and Kwack (1963) - which is recommended for use in liquid media - depends on the inherent Ca content of the agar. The experimental data presented show that a low concentration of Ca (0,15mM) within the semi-solid media is adequate for tomato pollen germination, although ImM Ca is optimal. Although this low Ca demand for tomato pollen germination is easily covered by the inherent Ca content of the agar, this is not the case for K and Mg, since in most cases there is a need for the external addition of K and Mg, especially when high purity agars are employed. Studies on the in vitro germination physiology of tomato pollen showed that the respiratory activity during incubation in liquid media depends on the tomato pollen viability and the incubation temperature. Tomato pollen respiration and germination proved to be susceptible to high temperatures (30° or 35°C), at which, the rate of respiration decreases significantly with time, following a reduction of pollen germinability and pollen tube growth. In addition, the experimental data show that the final rate of respiration after 6-7 hours of incubation may serve as an reliable indicator of pollen viability (which is estimated by pollen germinability x tube growth), in contrast to the initial rate of respiration and the CO₂ produced, over the 7 hour incubation period. Respiratory substrates such as succinate and NADH, respiratory uncouplers and ADP penetrated the intact tomato pollen grain and affected respiration, in a way that is not dependent on the rate of respiration. Studies of the reduction of the rate of respiration observed under a moderately high incubation temperature (30°C), revealed that although at the initial and middle stages of germination (after I and 4 hours of incubation) the addition of respiratory substrates strongly increased the rate of respiration indicating a lack of endogenous oxidisable substrates, after 7 hours of incubation substrate addition had less effect, indicating that the mitochondria at this stage present a diminished capacity for inoxidation of exogenously applied respiratory substrates. According to the results of this study, adverse climatic conditions negatively affect microsporogenesis and subsequently the fruit-set of tomato plants, primarily by the impairment of pollen productivity by the plants, rather than a lower viability of the pollen grains. Under low (32°C) temperatures, initially a reduction of pollen production per flower is observed, whereas pollen viability is reduced only after acute (temperatures lower than 7°C of higher than 38°C) or prolonged stress by extreme temperatures, especially in combination with low solar radiation. In particular, this study emphasizes the major role of solar radiation on the seasonal productivity of pollen, when temperature is not a limiting factor for microsporogenesis. By contrast, pollen viability did not exhibit such a relationship with radiation. Since inadequate radiation negatively affects microsporogenesis, even when the temperature regime within the greenhouse is optimal, adequate radiation has proved to be a necessary prerequisite for satisfactory production of viable pollen. On the other hand, high levels of solar radiation decrease the negative consequences of low temperatures on pollen production, suggesting an influence of the carbohydrates reserves of the plants on microsporogenesis, under unfavourable climatic conditions. Data derived from artificial pollinations at various seasons, showed that the correlation between pollen viability and its capacity to produce seeds is affected by climatic factors, as well as by the susceptibility of the genotype to set fruits under adverse climatic conditions. The female parts of the flowers are also implicated, possibly due to the supply of nutrients from stylar tissues to the growing pollen tube, and/or due to the viability of the ovules.Στην παρούσα διατριβή διερευνήθηκε η επίδραση των κλιματικών συνθηκών (με έμφαση στις ακραίες θερμοκρασίες και στα επίπεδα του φωτισμού), στην εποχιακή διακύμανση της παραγωγικότητας σε γύρη των φυτών τομάτας και της βιωσιμότητας της γύρης, καθ' όλη την περίοδο καλλιέργειας στο θερμοκήπιο (Οκτώβριος-Ιούλιος), γεγονός που σχετίζεται στενά με την παραγωγικότητα της καλλιέργειας, ιδιαίτερα υπό δυσμενείς περιβαλλοντικές συνθήκες. Η εκτίμηση της βιωσιμότητας της γύρης πραγματοποιήθηκε μέσω της in vitro βλάστησής της σε ημιστερεά (με άγαρ) τεχνητά μέσα βλάστησης. Εξαιτίας της έλλειψης πρότασης μέσου συγκεκριμένης σύστασης (standard medium) για τα ημιστερεά μέσα in vitro βλάστησης της γύρης της τομάτας, αρχικά διερευνήθηκε η επίδραση διαφόρων φυσικών (θερμοκρασία επώασης, pH υποστρώματος) και χημικών παραγόντων στην in vitro βλάστηση της γύρης δύο γονότυπων τομάτας σε ημιστερεά μέσα με άγαρ. Η εξωγενής προσθήκη διαφόρων χημικών στοιχείων (ρυθμιστές ανάπτυξης, αμινοξέα, βιταμίνες, φλαβονοειδή), έδειξε ότι η παρουσία τους δεν είναι απαραίτητη. Όμως, η μερική αντικατάσταση της σακχαρόζης από PEG-6000 (αλλά όχι από μαννιτόλη), καθώς και η προσθήκη των φλαβονοειδών quercetin και myricetin (σε συγκέντρωση 5 mg 1⁻¹) επέδρασαν θετικά στην βλαστικότητα της γύρης, η οποία επίσης ευνοήθηκε σε θερμοκρασία επώασης 15°C και μέσο με pH 6.5. Αποδείχθηκε περαιτέρω ότι, η in vitro βλάστηση της γύρης της τομάτας σε ημιστερεά υποστρώματα επηρεάζεται σημαντικά από το είδος και την καθαρότητα του μέσου ζελατινοποίησης που χρησιμοποιείται, με τα "καθαρότερα" μέσα (π.χ. άγαρ υψηλής καθαρότητας, αγαρόζη) να μην υποστηρίζουν ικανοποιητικά τις ανάγκες της γύρης της τομάτας σε ιόντα Κ, Mg και Ca για βλάστηση. Όμως, μέσα χαμηλότερης καθαρότητας αν και ενδεχομένως παρέχουν σε ικανοποιητικά επίπεδα τα απαραίτητα για βλάστηση ιόντα Κ, Mg και Ca, επηρεάζουν αρνητικά τη βλάστηση, πιθανά λόγω της παρουσίας στις προσμείξεις τους παρεμποδιστικών στοιχείων, γιατί η "έκπλυσή" τους με απεσταγμένο νερό βελτίωσε την αποτελεσματικότητά τους, απομακρύνοντας μέρος των προσμείξεων. Λόγω της αρνητικής επίδρασης στη βλάστηση της γύρης της τομάτας συγκεντρώσεων Ca στα μέσα βλάστησης άνω των 3mM, στα ημιστερεά μέσα εμφανίστηκε εξάρτηση της αποτελεσματικότητας της προσθήκης Κ, Mg και Ca κατά Brewbaker and Kwack (1963) που ενδείκνυται στα τεχνητά υγρά μέσα βλάστησης της γύρης πολλών φυτικών ειδών, από το ενδογενές περιεχόμενο των άγαρ σε Ca. Αντίστοιχα, αποδείχθηκε ότι οι απαιτήσεις της γύρης της τομάτας σε Ca για την in vitro βλάστησή της δεν είναι υψηλές (0,15mM Ca στα μέσα επαρκούν για ικανοποιητική βλάστηση, όταν η άριστη συγκέντρωση ανέρχεται σε ImM Ca) και καλύπτονται στις πλείστες των περιπτώσεων από το ενδογενές περιεχόμενο σε Ca των άγαρ, σε αντίθεση με τα Κ και Mg, που απαιτείται η εξωγενής προσθήκη τους, ιδίως όταν χρησιμοποιούνται μέσα ζελατινοποίησης υψηλής καθαρότητας. Η διερεύνηση της φυσιολογίας της in vitro βλάστησης της γύρης της τομάτας έδειξε ότι, η πορεία της αναπνευστικής δραστηριότητας της γύρης κατά την in vitro βλάστηση, καθορίζεται από τη ζωτικότητά της και τη θερμοκρασία επώασης. Η γύρη της τομάτας εμφανίζεται σχετικά θερμοευαίσθητη, με το ρυθμό αναπνοής να κάμπτεται έντονα με την πάροδο του χρόνου επώασης στις υψηλές θερμοκρασίες (30° και 35°C), που επίσης επηρέασαν αρνητικά τη βλαστικότητα των γυρεόκοκκων και την ανάπτυξη των γυρεοσωλήνων. Περαιτέρω, αποδείχθηκε ότι ο ρυθμός αναπνευστικής δραστηριότητας μετά 6-7 ώρες in vitro επώασης, μπορεί να αποτελεί αξιόπιστο κριτήριο για τη ζωτικότητα της γύρης της τομάτας, σε αντίθεση με τον αρχικό ρυθμό αναπνοής, καθώς και τη συνολική παραγωγή CO₂ μετά 7 ώρες επώασης. Η γύρη της τομάτας επέδειξε περατότητα και αντίδραση στην εξωγενή παροχή αναπνευστικών υποστρωμάτων, αποδεσμευτών της φωσφορυλίωσης και ADP, με την ένταση της αντίδρασης να μην εξαρτάται από το ρυθμό της αναπνευστικής δραστηριότητας. Η διερεύνηση των αιτίων που οδηγούν στην κάμψη της αναπνευστικής δραστηριότητας της γύρης σε μέτρια υψηλές θερμοκρασίες (30°C), μέσω της αντίδρασης του αναπνευστικού μηχανισμού σε διάφορα στάδια της in vitro βλάστησης της γύρης, στην εξωγενή παροχή αναπνευστικών υποστρωμάτων, αποδεσμευτών της φωσφορυλίωσης και ADP, έδειξε ότι ενώ στα αρχικά και ενδιάμεσα στάδια της βλάστησης (1 και 4 ώρες επώασης) παρατηρείται έντονα θετική επίδραση των αναπνευστικών υποστρωμάτων στο ρυθμό αναπνευστικής δραστηριότητας λόγω πιθανής εξάντλησης των ενδοκυτταρικών αποθεμάτων, μετά από 7 ώρες βλάστησης εμφανίζεται μείωση της αντίδρασης αυτής, υποδηλώνοντας ίσως την απώλεια της ικανότητας των μιτοχονδρίων να οξειδώνουν τα εξωγενώς παρεχόμενα αναπνευστικά υποστρώματα. Τα πειραματικά δεδομένα υποστηρίζουν πως η επίδραση των κλιματικών παραγόντων στη μικροσπορογένεση και κατ’ επέκταση στην καρπόδεση της τομάτας, είναι εντονότερη στην παραγωγικότητα των φυτών σε γύρη, παρά στη βιωσιμότητα της παραγόμενης γύρης. Υπό χαμηλές (32°C) θερμοκρασίες παρατηρείται αρχικά μείωση της παραγωγής γύρης ανά άνθος, ενώ η βιωσιμότητα περιορίζεται μόνο μετά από οξεία (λόγω ακραία χαμηλών 38°C θερμοκρασιών) ή παρατεταμένη καταπόνηση λόγω μη ευνοϊκών θερμοκρασιών, καθώς και σε συνδυασμό τους με χαμηλό φωτισμό. Αντίστοιχα, η παρούσα μελέτη ανέδειξε το φωτισμό σε κυρίαρχο παράγοντα για την εποχιακή διακύμανση της παραγωγικότητας των φυτών σε γύρη, τουλάχιστον όταν η θερμοκρασία δεν αποτελεί περιοριστικό παράγοντα για τη μικροσπορογένεση, ενώ η βιωσιμότητα της γύρης δεν επέδειξε αντίστοιχη εξάρτηση από τα επίπεδα φωτισμού. Τα επαρκή επίπεδα φωτισμού αποτελούν απαραίτητη προϋπόθεση για την ικανοποιητική παραγωγή βιώσιμης γύρης, αφού ο ανεπαρκής φωτισμός επιδρά αρνητικά στη μικροσπορογένεση ακόμα και όταν οι θερμοκρασίες εντός του θερμοκηπίου κυμαίνονται σε άριστα επίπεδα. Αντίθετα, υψηλά επίπεδα φωτισμού αμβλύνουν τις αρνητικές επιδράσεις των χαμηλών θερμοκρασιών στην παραγωγικότητα των φυτών σε γύρη, υποδηλώνοντας εμπλοκή των αποθεμάτων των φυτών σε υδατάνθρακες στη μικροσπορογένεση υπό δυσμενείς κλιματικές συνθήκες. Δεδομένα από ελεγχόμενες επικονιάσεις σε διαφορετικές εποχές καλλιέργειας, έδειξαν ότι η σχέση της βιωσιμότητας της γύρης και της σποροπαραγωγικής της ικανότητας επηρεάζεται τόσο από τις κλιματικές συνθήκες, όσο και από την ευαισθησία του γονότυπου στην καρπόδεση υπό μη ευνοϊκές συνθήκες, με εμπλοκή και των θηλυκών μερών του άνθους, ενδεχομένως είτε ως προς την τροφοδοσία του αναπτυσσόμενου γυρεοσωλήνα από το στύλο, είτε/και ως προς τη βιωσιμότητα των ωαρίων

Strategies to communicate pregnancy complications: a systematic review and practical points for healthcare professionals

Purpose/methods: This systematic review aims to provide an overview of strategies available for healthcare professionals (HCPs) to effectively communicate unexpected news in pregnancy, specifically for the most common pregnancy complications. Three medical databases and grey literature were searched until March 2023 using subject headings and keywords. Snowball techniques were also used. The articles were reviewed at each stage of screening independently by two separate authors. Qualitative, quantitative and mixed methods studies were included. Recent findings: Forty-three studies were included and grouped according to the gestational age of the pregnancy complication - miscarriage, increased risk screening, foetal conditions, stillbirth. The main key points for communication were outlined at each specific complication and eventually the six common themes that emerged from all the categories were included in the acronym PRICES (Preparation - Referral - Individualized care - Clarity - Empowerment - Sensitivity). Summary: Given the negative impact of failed communications both in pregnancy outcomes and patients' experience, we advocate that communication training for HCP providing pregnancy care should be mandatory, and skills should be updated at regular intervals. Tools like our acronym PRICES can be used during teaching HCPs how to communicate more effectively

Seeded and Parthenocarpic Cherry Tomato Fruits Exhibit Similar Sucrose, Glucose, and Fructose Levels, Despite Dissimilarities in UGPase and SPS Gene Expression and Enzyme Activity

© 2014, Springer Science+Business Media New York. Farmers often resort to the production of auxin-induced parthenocarpic tomato fruits to overcome the adverse climatic conditions which are unfavorable for sufficient fertilization and to lengthen the production period. Even though this practice improves the out-of-season yield, it often undermines fruit quality. In the current study, we examined the effect of induced parthenocarpy in cherry tomato cv. Conchita on the concentration of the main sugars, and on the expression, the activity and the localization of UDP-glucose pyrophosphorylase (UGPase) and sucrose phosphate synthase (SPS), enzymes that are actively involved in sucrose metabolism. Minor differences were detected in sugar levels of seeded and parthenocarpic fruits, whereas considerable variances were found in transcript accumulation and enzyme activities of both UGPase and SPS. Moreover, both proteins were present in the developing seeds. Our data indicate that although induced parthenocarpy significantly influences sucrose metabolism, it has a negligible effect on sugar levels

Gene transcript accumulation and enzyme activity of β-amylases suggest involvement in the starch depletion during the ripening of cherry tomatoes

© 2015 The Authors. Published by Elsevier B.V. All rights reserved. The flavor of tomato fruits is mostly influenced by the accumulation of sugars and organic acids. During fruit ripening a conversion of starch to sugars occurs, which modulates significantly the taste and consequently the quality of the ripe tomato fruits. β-Amylases, a group of major starch hydrolytic enzymes involved in starch degradation were examined in developing cherry tomatoes. Our results suggest that the enzyme activity and the gene transcript accumulation of plastidial β-amylase isoenzymes were elevated during the late stages of fruit development indicating a participation of the enzyme in starch depletion and in the increase of total soluble sugar levels in ripe tomatoes

The Impact of Salinity on Growth, Physio-Biochemical Characteristics, and Quality of <i>Urospermum picroides</i> and <i>Reichardia picroides</i> Plants in Varied Cultivation Regimes

Salinity stress is severely affecting modern horticulture and puts food security under threat for current and future generations. The aim of the present study was to evaluate the effect of saline conditions (three salinity levels: 2.0, 5.0 and 10.0 dS m−1) on the growth, physiological processes and quality of two wild edible species (Urospermum picroides and Reichardia picroides) grown under three different cropping systems (pots indoors (GP) and outdoors (FP); and floating hydroponics (FH)). Our results indicate that high salinity affected growth parameters in all the studied cropping systems in the case of U. picroides, whereas R. picroides was not affected only when grown in pots outdoors. Moreover, total soluble solids content and titratable acidity in both species were not affected by high salinity for any of the cropping systems, except for in the case of FP system. Similarly, carotenoids content decreased under high salinity when both species were grown in the FP system. A varied effect was recorded for total phenolic compounds content in response to salinity levels, although the FP system resulted in considerably higher phenolics accumulation in both species, while proline content increased when plants were subjected to high salinity, regardless of the cropping system. The antioxidant activity also varied among the studied treatments for both assays (TEAC and FRAP), although cultivation outdoors in pots resulted in considerably higher values compared to the other systems. Finally, nitrate content showed decreasing trends with increasing salinity in plants grown in the GP (both species) and FP system (only U. picroides), whereas no significant differences in physiological parameters in comparison to the control treatment were recorded, except for the stomatal conductance (FP and GP system) and transpiration rate (FP) of R. picroides plants. In conclusion, it seems that the tested plant species responded differently to the salinity treatments but they both displayed a lack of severe stress even at high salinity

Impact of Salinity on the Growth and Chemical Composition of Two Underutilized Wild Edible Greens: Taraxacum officinale and Reichardia picroides

Soil salinization is one of the major environmental factors responsible for limited crop production throughout the world. Therefore, there is urgent need to find tolerant/resistant species to exploit in commercial cultivation systems. In this context, the valorization of wild edible greens for human consumption and/or medicinal purposes is gaining more and more interest. The aim of the present work was to study the effect of salinity, e.g., electrical conductivity: 2 mS cm−1 (nutrient solution EC), 6 mS cm−1 and 10 mS cm−1 on plant growth and chemical composition of Reichardia picroides and Taraxacum officinale plants grown in a floating hydroponic system. The results showed that R. picroides is a moderately salt-tolerant species, as the majority of plant growth parameters determined were not negatively affected under the treatment of 6 mS cm−1. On the other hand, the growth parameters of T. officinale plants were severely affected under the same conditions. Moreover, high salinity levels (EC at 10 mS cm−1) impaired the growth of both species. The content of leaves in chlorophylls (a, b and total), carotenoids+xanthophylls and total soluble solids was not significantly affected by the tested EC levels in both species, whereas the titratable acidity increased under the treatment of 10 mS cm−1. Moreover, R. picroides exhibited a more effective adaptation mechanism against saline conditions than T. officinale, as evidenced by the higher accumulation of osmolytes such as proline and the higher shoot K content, probably through a more efficient K/Na selectivity. In conclusion, both species were severely affected by high salinity; however, R. picroides showed promising results regarding its commercial cultivation under moderate salinity levels, especially in regions where resources of high-quality irrigation water are limited