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The effectiveness of apricot cultivation is greatly threatened by frost damage to flower buds during the dormancy period. One of the most important aspects of the evaluation of cultivars is therefore the determination of their frost tolerance. In this paper, the frost hardiness of flower buds of 16 apricot cultivars was investigated in three dormancy periods, applying a standardised artificial freezing test protocol and determining LT50 values. The results showed that both the genotypes and the yearly climatic conditions had a significant effect on frost tolerance. A genotype generally determines the potential maximum of its frost tolerance (‘Sweet Red’ and ‘Primaya’ were very sensitive to frost every year, while ‘Harlayne’ and ‘Rózskajszi C.1406’ could be considered as frost hardy). Flower buds can reach different levels of frost resistance each year depending on the temperature conditions during the hardening and dehardening periods. From the point of view of yield security, it is essential when planning an orchard, to take into account and harmonise the frost hardiness of the cultivars selected and the growing site conditions. Therefore, it is very important to have adequate information about the frost hardiness of different apricot cultivars, which should be included in cultivar descriptions. This paper is intended to contribute to this goal.

Flower bud development of fruit trees plays a key role in their climatic adaptation. It is closely related to dormancy release that determines winter frost susceptibility. Detailed characterisation of flower bud development of 25 almond (Prunus amygdalus L. Batsch) accessions representing wide range of flowering times have been performed by microsporogenesis and pistil growth studies for 3 years. Six developmental stages were distinguished in the process of microsporogenesis, while pistil development could be classified into four phases. The examined cultivars showed significant differences in the length and occurrence of microspore developmental stages and year effect was observed. On the basis of the length of microsporogenesis stages, cultivars were clustered into five main groups. The shortest periods of archesporium and microsporogenesis as a sum were detected in accessions ‘Eriane’, ‘5/15’ and ‘1/7’ (with an average of 20 and 138 days in all three), while the longest ones were determined in ‘Constanti’ and ‘Vairo’ (65 and 160 days in both), respectively. The increment of pistil length was suspended during the dormancy period and after dormancy release, it was accelerated first at a slow rate followed by a few days of rapid growth prior to blooming. In order to determine the date of endodormancy release, these three methods – microsporogenesis, pistil length studies, and forcing of shoots – were analysed. All methods revealed significant differences among accessions. The dormancy release estimated by microsporogenesis studies showed the highest variability among the three methods used.

Listeria monocytogenes is a pathogenic bacterium that can form biofilms in food processing plants, allowing the bacteria to survive despite the control measures applied. As the surface of the bacteria is covered with versatile polysaccharides and proteins, these influence the interactions of the bacterium with any surface. The unique properties and high stability of fungal proteins make them good candidates for the control of bacteria by targeting surface structures. We screened a group of fungal lectins and protease inhibitors from different fungal species, protein folds and known targets for their antibacterial and antibiofilm activity against model strains of Listeria innocua and Listeria monocytogenes. Several of them significantly decreased the viability of biofilm bacteria, but had no effect on bacterial growth parameters at 37°C and thus had no antibacterial activity. Fungal lectins significantly impaired biofilm development even at room temperature, which was attributed to exposure to lectins during adhesion. The tested fungal proteins also reduced biofilm development on biological model surfaces. The observed antibiofilm activity of fungal proteins suggests that they have the potential to modulate interactions between bacteria and/or between bacteria and surfaces, which could be used in the future to reduce surface contamination by Listeria. [ABSTRACT FROM AUTHOR]

Recently, non-Saccharomyces yeasts have gained considerable attention as a novel strategy to enhance the aroma diversity of alcoholic beverages. This study explores the effect of sequential fermentations involving Lachancea thermotolerans and Torulaspora delbrueckii on the aroma profile of apple spirits. Additionally, the influence of time, temperature, and alcohol content on the volatile composition during the maturation of distillates was described. The results revealed that distillates obtained from mixed cultures exhibited improved aroma complexity, primarily due to increased ester production. Torulaspora delbrueckii positively influenced the synthesis of 2-phenethyl acetate, diethyl succinate, and hexyl acetate. Lachancea thermotolerans promoted the formation of ethyl lactate, ethyl myristate, and ethyl phenylacetate while reducing the concentration of higher alcohols. During maturation, changes in aroma constituents were observed. In general, the concentration of the investigated volatile compounds tends to decrease during maturation, with this trend being strongly related to the alcohol content of the distillates. Temperature did not affect the variations of methanol, acetaldehyde, 1-propanol, 2-butanol, 2-methyl-1-butanol, cis-2-hexen-1-ol, and diethyl succinate. Regarding esters, increases were observed in the concentration of ethyl octanoate, ethyl myristate, and, under certain circumstances, ethyl acetate and isoamyl acetate. No correlation was found between changes in acetaldehyde and the conditions tested. [ABSTRACT FROM AUTHOR]

In the framework of an ongoing gene conservation programme in the Tolna Hills Region, Hungary, a total of 41 site plots were selected on agricultural land that had recently been used as grassland, meadow or vineyard. Aims of our study were (i) to test the taxonomic status of relic oak trees growing out of forested lands; (ii) to verify the origin of relic trees whether they regenerated by sprouts and suckers or by seeds in order to estimate their age and origin (nativeness); (iii) to test their microhabitats to see if forest-specific plant and fungal species were presented; (iv) and to test species to see if their presence linked to any forest vegetation in the past. Furthermore, the land-use type did not show a significant effect on the abundance of woody, dicot herbaceous, or monocot herbaceous plants recorded on sites based on maps from 1941 or earlier. The follow-up univariate ANOVA revealed a significant direct effect of recent land-use type (of 2022) on monocot herbaceous plants (F(3,33) = 5.21, p < 0.01). Additionally, a significant but weaker effect was observed on woody plants (F(3,33) = 3.22, p < 0.05). The overall past effect of land-use type showed a significantly high positive correlation between the abundance of woody plants and the number of times the maps showed forest or forest boundary land-use types (R = 0.46, p < 0.01). The plots have likely preserved and sustained the microhabitats of the native forest vegetation that was once distributed in the region. The site plots of relic oak trees, considered as flagstone habitats, create opportunities for gene flow, not only for the species with dispersal or discontinuous distribution, but also for the Vergilius oak populations. Therefore, relic trees and their microhabitats might have an important role in the mating system of various species and might also be valuable resources for genetic conservation programmes. [ABSTRACT FROM AUTHOR]

Though profitable crop production can be more simply achieved by using synthetic pesticides, the research of alternative plant protection solutions is necessary. The effect of the volatile oils of cinnamon, thyme, and a copper ingredient fertilizer were tested for their activity against apple scab and powdery mildew in apple orchards in 2014 and 2017. Oils applied alone or in combination were effective against apple scab in 2014 and in 2017 and against powdery mildew on leaves in 2017. The copper ingredient fertilizer product improved the efficacy of the oils. The results of these trials show that the tested volatile oils are suitable candidates for further research and for the development of organic fungicides against the diseases of apple.