Changes in germination and glyoxylate and respiratory enzymes of Pinus pinea seeds under various abiotic stresses

Abstract This study examined Pinus pinea seeds for their tolerance to osmotic potentials of −0.30MPa (10% polyethylene glycol [PEG]), −0.58MPa (18% PEG), −0.80MPa (21% PEG), −1.05MPa (24% PEG), pH values of 4, 5, 6, 7, 8, 9, 10, and different calcareous solutions (5, 10, 20 and 40% CaCO3). The main enzymes of glyoxylate cycle and respiratory pathway were tested. Pinus pinea seeds under no stressful condition (Control) and 5% CaCO3 reached 100% of germination. Higher concentrations of CaCO3 (20, 40%) and lower pH (4–5) adversely affected seed germination percentage, glyoxylic and respiratory enzyme activities. PEG caused the most detrimental effects on Pinus seeds; increasing the osmotic potential the germination was completely inhibited. These results suggest that Pinus pinea is able to germinate in calcareous and alkaline soils rather than in soils with lower water availability and acidic conditions

Erratum to: Biological effects of water-soluble soil phenol and soil humic extracts on plant systems

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Selection of Wine Saccharomyces cerevisiae Strains and Their Screening for the Adsorption Activity of Pigments, Phenolics and Ochratoxin A

Ochratoxin A is a dangerous mycotoxin present in wines and is considered the principal safety hazard in the winemaking process. Several authors have investigated the ochratoxin A adsorption ability of Saccharomyces cerevisiae yeasts, and specifically selected strains for this desired trait. In the present work, a huge selection of wine yeasts was done starting from Portuguese, Spanish and Italian fermenting musts of dierent cultivars. Firstly, 150 isolates were collected, and 99 non-redundant S. cerevisiae strains were identified. Then, the strains were screened following a multi-step approach in order to select those having primary oenological traits, mainly (a) good fermentation performance, (b) low production of H2S and (c) low production of acetic acid. The preselected strains were further investigated for their adsorption activity of pigments, phenolic compounds and ochratoxin A. Finally, 10 strains showed the desired features. The goal of this work was to select the strains capable of absorbing ochratoxin A but not pigments and phenolic compounds in order to improve and valorise both the quality and safety of red wines. The selected strains are considered good candidates for wine starters, moreover, they can be exploited to obtain a further enhancement of the specific adsorption/non-adsorption activity by applying a yeast breeding approach

Effects of different thinning intensities on soil carbon storage in Pinus laricio forest of Apennine South Italy

This study investigated, in a Pinus laricio forest of south Italy, how systematic thinning of different intensities (intense thinning, T45; moderate thinning, T25; clear cut, CC; and no thinning, T0) affected soil biological properties, organic matter trend and carbon (C) storage in soil and plants. Soil carbon content and carbon/nitrogen (C/N) ratio were significantly higher in the T45 than in control, T25 and CC. Under T45, the soils had also the highest enzymatic activities, microbial biomass carbon (MBC) and colonies of fungi and bacteria. The humification parameters (humification ratio, HR; the degree of humification, DH; humification index, HI) indicated T45 as the best silvicultural practice-approach method to manage Pinus laricio forest for increasing soil carbon storage. The dendrometric parameters evidenced that T45 caused the greatest increment in wood growth (diameter and height), showing that the positive effect of the intense systematic thinning (T45) on the mechanical stability of plantation was related to the ability of trees to accumulate large amounts of carbon in their wood tissues. These data were confirmed by wood density value that was the highest in pine trees under the T45. This study showed that in Pinus laricio forest under T45 C stock increased in soil and plant, already 4 years after thinning.This is a post-peer-review, pre-copyedit version of an article published in European Journal of Forest Research. The final authenticated version is available online at: [http://dx.doi.org/10.1007/s10342-017-1077-9

Soil biodegradation of nutrients enriched cellulose- and chitosan-derived mulching films for sustainable horticulture

In 2019, global plastics production reached 370 million tons, of which 58 million tons were in Europe[1]. If the plastic use in agriculture accounts for 2% of the global production[2], more than 7 million tons of plastic were used in 2019 in the agricultural sector. Mulch films represent the major source of plastic contamination in agricultural soils[3]. The agricultural surface area covered by plastic films in Europe is four times larger than that covered by greenhouses and six times that of low tunnel hoops. Over the past decades, biodegradable biopolymer mulching films (BPMFs) have been developed to reduce soil pollution by non-biodegradable plastic debris[4] and to expand the circular bioeconomy[5]. In Europe, since 1999, low density polyethylene mulches (LDPMs) have to be dismissed after their use to remove source of pollutants that can reach up to 200 kg ha-1[6] and decline soil quality, crop growth, and yield[7]. BPMFs are a sustainable alternative to conventional LDPMs. Unlike LDPMs, BPMFs, at the end of their lifetime, are tilled into soil where they are expected to be biodegraded by soil microorganisms[8]. Moreover, BPMFs show an estimated saving of about 500 kg of CO2 equivalent per hectare in comparison with LDPMs. Conversely, the impact of LDPMs in intensive horticulture could result higher than weed control by herbicides as by life cycle assessment (LCA)[9]. BPMFs can be obtained by thermo-plasticizing, solvent casting and spraying processes by using renewable and biodegradable raw materials such as starch, cellulose, chitosan, alginate, glucomannan[10] and glycerin as plasticizer[11]. Cellulose and chitosan, being the two most abundant natural biopolymers on Earth, have been proposed as the best candidates for BPMFs production. Unfortunately, the high tendency for intra- and intermolecular hydrogen bonding confers undesirable mechanical properties. The addition of plasticizer as well as fillers overcome this problem[12] modifying mechanical and functional properties of the materials. To sum up, biopolymer blending is an effective strategy to reuse cellulose and chitosan-containing by-products and develop materials with novel mechanical characteristics[13]. Moreover, the functional properties of these materials can be tuned by doping them with suitable compounds[14]. Based on what stated above, and considering that soil fertility, crop growth and yield, are generally N and P limited, the core idea of this project is the preparation of N- and P-enriched BPMFs for soil mulching, in order to slowly release soluble nutrients into soils upon their biodegradation. The latter aspect is of great importance because a proper C:N:P ratio can lead to an increase of soil-dwelling organisms thus contributing to nutrient cycling in the soil-plant system, soil C sequestration and biological fertility status[15]. Moreover, repeated additions of BPMFs over long term can increase the amount of nutrients, thus reducing the use of external inputs (e.g. synthetic fertilizers) within a circular economy perspective. The specific aim of the proposed research are: i) to set up a method for the preparation of suitable BPMFs enriched with N and P; ii) to characterize novel BPMFs and evaluate their structure, degradation kinetics, and isotopic composition iii) to assess the impact of the innovative BPMFs on soil nutrient cycling and crop growth and yield; iv) to evaluate the effect of the innovative BPMFs on soil prokaryotes and micro-arthropods communities; v) to speed-up the biodegradation of the innovative BPMFs by spraying them at the end of their lifecycle with selected microorganisms and by adding the recipient soil with earthworms; vi) to evaluate the innovative BPMFs using the LCA methodology and to investigate its role within the circular economy. Bibliography [1] Plastic Europe, 2020. Website https://www.plasticseurope.org/it/resources/publications/4312-plastics-facts-2020 accessed on 05.01.2021 [2] Vox, G., Loisi, R.V., Blanco, I., Mugnozza, G.S., & Schettini, E. (2016). Agriculture and Agricultural Science Procedia, 8, 583-591. [3] Wenqing, H., Enke, L., Qin, L., Shuang, L., Turner, N., C. & Changrong, Y. 2014. World Agriculture, 4, 3236. [4] Sanchez-Hernandez J.C., Capowiez Y. & Ro K.S., 2020. ACS Sustainable Chemistry & Engineering, 8, 4292-4316. [5] Karan, H., Funk, C., Grabert, M., Oey, M., & Hankamer, B., 2019. Trends in Plant Science, 24, 237-249. [6] Razza, F., Guerrini, S., & Impallari, F.M., 2019. Acta Horticulturae, 1252, 77-84. [7] Hou, L., Xi, J., Chen, X., Li, X., Ma, W., Lu, J., Xu J. & Lin, Y. B, 2019. Journal of Hazardous Materials, 378, 120774. [8] Kyrikou, I., & Briassoulis, D., 2007. Journal of Polymers and the Environment, 15, 125–150 [9] Tasca, A. L., Nessi, S., & Rigamonti, L., 2017. Journal of Cleaner Production, 140, 725-741 [10] Santagata, G., Malinconico, M., Immirzi, B., Schettini, E., Scarascia Mugnozza, G., & Vox, G., 2014. Acta Horticulturae 1037(1037), 921-928. [11] D’Avino, L., Rizzuto, G., Guerrini, S., Sciaccaluga, M., Pagnotta, E., & Lazzeri, L. (2015). Industrial Crops and Products, 75, 29-35. [12] Chen, P., Xie, F., Tang, F., & McNally, T. (2021). Influence of plasticiser type and nanoclay on the properties of chitosan-based materials. European Polymer Journal, 144, 110225. [13] Bajpai, A.K., Shukla, S. K., Bhanu, S., & Kankane, S., 2008. Progress in Polymer Science, 33(11), 1088-1118 [14] Sohaimy, M.I.H.A., & Isa, M.I.N.M. et al., 2020. Polymers. 12, 2487 [15] Cleveland, C.C., & Liptzin, D., 2007. Biogeochemistry 85, 235–25

Persistence and Effect of a Multistrain Starter Culture on Antioxidant and Rheological Properties of Novel Wheat Sourdoughs and Bread

Food consumers make decisions primarily on the basis of a product’s nutritional, functional, and sensorial aspects. In this context, this study evaluated the persistence in sourdough of a multistrain starter culture from laboratory to bakery plant production and the effect of the starter on antioxidant and rheological properties of sourdoughs and derived bread. Lactobacillus sanfranciscensis B450, Leuconostoc citreum B435, and Candida milleri L999 were used as a multispecies starter culture to produce a sourdough subsequently used to modify two traditional sourdoughs to make novel bread with improved health and rheological properties. Both these novel bakery sourdoughs showed the persistence of L. sanfranciscensis B450 and C. milleri L999, and showed a significantly different lactic acid bacteria (LAB) concentration from the traditional sourdoughs. The novel sourdough PF7 M had a higher phenolic content (170% increase) and DPPH (8% increase) than the traditional bakery sourdough PF7 F. The novel sourdough PF9 M exhibited an improvement in textural parameters. Further research would be useful on the bioavailability of bio-active compounds to obtain bread with improved characteristics

Acido succinico quale causa della mancata rifermentazione spontanea in bottiglia del Lambrusco

La rifermentazione in bottiglia dei Lambruschiè una pratica consolidata, che conferisce alvino caratteristiche sensoriali apprezzate daiconsumatori. Recentemente, e con sempremaggiore frequenza, è stata osservata la mancatarifermentazione del prodotto in bottiglia. Studipreliminari hanno messo in evidenza che lafrequenza della mancata rifermentazione èmaggiore nei vini imbottigliati precocementee senza aggiunta di lieviti. Inoltre, tutti icampioni esaminati che manifestano mancatarifermentazione contestualmente presentano valoridi acido succinico pari a 3 g/L. Va sempre tenutoconto che la crescita microbica è condizionatanon da un singolo fattore, ma da più fattori,perciò abbiamo allestito delle sperimentazioni chetenessero conto dei parametri più significativi,quali pH, densità di inoculo, concentrazione diacido succinico e concentrazione di etanolo. Unaprova di rifermentazione in bottiglia in condizionidi cantina ha definitivamente confermato la forteazione inibitrice dell’acido succinico sullo sviluppocellulare di Saccharomyces cerevisiae. I risultatisono coerenti con l’ipotesi che l’acido succinico,nell’ambito dei valori di pH e di concentrazionidi inoculo studiati, sia la causa della mancatarifermentazione.The spontaneous secondary alcoholicfermentation of the Lambrusco wine in bottle isa well-established practice that confer it someappreciated sensorial characteristics. Recently, andwith more frequency, it was observed the lack ofspontaneous secondary alcoholic fermentation inbottle. Preliminary studies have put in evidencethat the frequency of this problem is greater inearly bottled wines, produced without the additionof selected yeasts. Moreover, all the samples withthis problem have, at the same time, a succinicacid concentration of 3 g/L. These observationshave allowed the AA. to formulate the hypothesisthat succinic acid, in the presence of other limitingconditions, could be the cause of the lackedspontaneous secondary alcoholic. Since microbialgrowth is influenced by many factors, the AA. haveperformed several experiments considering themost significant parameters: pH, inoculum density,succinic acid content, and ethanol concentration.A secondary alcoholic fermentation test, carriedout under winery conditions, has confirmed thestrong inhibiting action of the succinic acid onSaccharomyces cerevisiae growth. The resultsare consistent with the hypothesis that, for thetested range, succinic acid is the reason of lackedspontaneous secondary alcoholic fermentation ofthe Lambrusco wine in bottl

Effects of Gap Size and Cardinal Directions on Natural Regeneration, Growth Dynamics of Trees outside the Gaps and Soil Properties in European Beech Forests of Southern Italy

The present study was focused on how cardinal directions inside gaps of different sizes (small, 200 m2; medium, 400 m2; and large, 600 m2) can affect soil characteristics and tree regeneration. Additionally, the effects of gap size on the growth dynamics of trees outside the gaps were evaluated. The study was carried out in a European beech stand located in Aspromonte National Park (Southern Apennines, Calabria, Italy). Microclimatic variables, physical, chemical, and biochemical soil properties, natural regeneration density, and growth trees outside the gaps density of natural regeneration were assessed. This study provided evidence for an important effect of cardinal points on micro-environmental parameter variability, nutrient cycle, physic-chemical soil properties, water availability, and biological processes such as trees growth and regeneration. The European beech natural regeneration was most abundant in the south part of the gaps. Thus, we can state that cardinal points affect the trees natural regeneration in a species-specific manner. The new microclimatic conditions due to the gap opening had positive effects on the tree growth located along the gap edge, especially in the trees sampled on the edges of the medium gaps. On the contrary, the trees located in the forest recorded a productivity coherent with the period prior the gap opening. In medium-sized gaps, the combination and interaction of microclimatic and soil parameters (humification and mineralization process and microbial activity) created the best conditions for beech natural regeneration and favored an increase in the productivity of the trees at the edge of the gaps