Responses of Persian walnut on foliar applications of different biostimulants.

Biostimulants have different effects on plants. The aim of this paper is to determine responses of the 'Alsószentiváni 117' walnut cultivar on foliar applications of different biostimulants (Wuxal Ascofol, Kondisol, Alga K Plus). The nut traits (nut length, nut diameter, nut weight, kernel weight) and some phenolic compounds of the kernel were measured and detected. In 2020, during warmer early spring weather conditions under pistillate flowering receptivity, chlorogenic acid and quercetin content of kernels treated with Kondisol were higher than in control. All biostimulants influenced positive effects on catechin and rutin content, as well as treatments made with Wuxal Ascofol and Kondisol increased the juglon content of the kernel. In 2021, when the spring weather was typical for that period, only the Kondisol treatments had increasing effects on the catechin and chlorogenic acid content, than the control. The rutin and quercetin concentrations reached the highest value in this trial by Alga K Plus applications. The juglon content decreased in this year compared to the control. The pirocathecin, cinnamic acid, and gallic acid (except Wuxal Ascofol treatment in 2021) content decreased in all treatments in both observed years. Responses of woody fruit species on biostimulants applications depend on the weather conditions. Biostimulants had positive effects on the nut size characteristics in both observed years.

Assessment of Berries of Some Sea Buckthorn Genotypes by Physicochemical Properties and Fatty Acid Content of the Seed.

Sea buckthorn (Hippophae rhamnoides L.) is consumed mainly in its processed form. Therefore, the investigation of the physicochemical properties of its berries is a current task in the aspect of food processing. The aim of this study was to determine the physicochemical parameters (soluble solid content, total titratable acidity, sugar/acid ratio), color characteristics (L*, a*, b*) and fatty acid profile of five varieties ('Askola', 'Clara', 'Habego', 'Leikora', 'Mara') and one Hungarian candidate, R-01, to establish a basis for experiments on the processability of the whole berries (e.g., drying). The weight of the berry of 'Leikora' (0.64 g) was significantly higher than the other investigated fruits. The differences between the values of soluble solid content (6.3-10.84 °Brix) and titratable acid (1.4-3.7%) content of berries were significant. 'Mara' had the highest sugar/acid ratio. Regarding the fatty acid profile, the amount of unsaturated fatty acids was measured between 72.6-83.4%, including polyunsaturated fatty acids, which were between 32.3-58.1%. The seeds of the tested samples contained high concentrations of linoleic acid (17.0-33.2%) and linolenic acid (15.3-24.9%), mainly in the case of the 'Mara', 'Clara' and 'Askola' varieties. Candidate R-01 could be used as a raw material for functional foods due to its significant content of palmitoleic acid and a favourable omega-6/omega-3 ratio.

Effects of the repression of GIGANTEA gene StGI.04 on the potato leaf transcriptome and the anthocyanin content of tuber skin.

BACKGROUND: GIGANTEA (GI) is a plant-specific, circadian clock-regulated, nuclear protein with pleiotropic functions found in many plant species. This protein is involved in flowering, circadian clock control, chloroplast biogenesis, carbohydrate metabolism, stress responses, and volatile compound synthesis. In potato (Solanum tuberosum L.), its only role appears to be tuber initiation; however, based on findings in other plant species, we hypothesised that the function of GI in potatoes is not restricted only to tuberisation. RESULTS: To test this hypothesis, the expression of a GI gene in the commercial potato cultivar 'Désirée' was repressed, and the effects of repression at morphological and transcriptome level were investigated. Previously, two copies of GI genes in potato were found. A construct to reduce the mRNA levels of one of these genes (StGI.04) was assembled, and the effects of antisense repression were studied in greenhouse-grown plants. The highest level of repression reached around 50%. However, this level did not influence tuber formation and yield but did cause a reduction in tuber colour. Using high-performance liquid chromatography (HPLC), significant reductions in cyanidin 3,5-di-O-glucoside and pelargonidin 3,5-di-O-glucoside contents of tuber peels were detected. Anthocyanins are synthesized through a branch of the phenylpropanoid pathway. The transcriptome analysis indicated down-regulation in the expression of PHENYLALANINE AMMONIA LYASE (PAL), the LEUCOANTHOCYANIDIN OXIDISING enzyme gene LDOX, and the MYB-RELATED PROTEIN Hv1 (MYB-Hv1), a transcription factor coding gene, which is presumably involved in the regulation of flavonoid biosynthesis, in the leaves of a selected StGI.04-repressed line. Furthermore, alterations in expression of genes affecting the circadian clock, flowering, starch synthesis, and stress responses were detected in the leaves of the selected StGI.04-repressed line. CONCLUSIONS: We tested the effects of antisense repression of StGI.04 expression in potatoes and found that as with GI in other plant species, it influences the expression of the key genes of the circadian clock, flowering, starch synthesis, and stress responses. Furthermore, we detected a novel function of a GI gene in influencing the anthocyanin synthesis and potato tuber skin colour.

Degradation of Anthocyanin Content in Sour Cherry Juice During Heat Treatment.

Sour cherry juices made from two sour cherry cultivars (Érdi botermo and Kántorjánosi 3) were investigated to determine their total anthocyanin content and half-life of anthocyanins during heat treatment at different temperatures (70, 80 and 90 °C) for 4 h. Before the heat treatment, Érdi botermo juice had higher anthocyanin concentration (812 mg/L) than Kántorjánosi 3 juice (513 mg/L). The greatest heat sensitivity of anthocyanins was measured at 90 °C, while the treatments at 80 and 70 °C caused lower thermal degradation. The loss of anthocyanins in Érdi botermo juice after treatment was 38, 29 and 18%, respectively, while in Kántorjánosi 3 juice losses of 46, 29 and 19% were observed, respectively. At 90 °C sour cherry Érdi botermo juice had higher half-life (t1/2) of anthocyanins, while the Kántorjánosi 3 juice had higher t1/2 values at 70 °C. Cyanidin-3-glucosyl-rutinoside was present in higher concentrations in both cultivars (Érdi botermo: 348 and Kántorjánosi 3: 200 mg/L) than cyanidin-3-rutinoside (177 and 121 mg/L) before treatment. However, during the experiment, cyanidin-3-rutinoside was proved to be more resistant to heat. Comparing the two varieties, both investigated pigment compounds were more stable in Kántorjánosi 3 than in Érdi botermo. Degradation rate of anthocyanins was cultivar-dependent characteristic, which should be taken into account in the food production.

Investigation of dietary important components in selected red fleshed apples by GC-MS and LC-MS.

Three red-fleshed apple cultivars (Malus 'Geneva': GFV-03, Hungarian hybrid: GFV-04, Malus pumila Niedwetzkyana: GFV-05) were investigated for their chemical composition by sHS-SPME-GC-MS and HPLC-DAD-MS/MS analytical techniques. In cultivars GFV-03 and GFV-05 sesquiterpene α-farnesene were dominant while the alphatic esters were present mostly in traces. In GFV-04 - the new disease resistant advanced selection of the Hungarian apple breeding program - hexanol and hexyl 2-methylbutanoate were present in larger amounts while the amount of α-farnesene was lower than the other two cultivars. Using HPLC-DAD-MS/MS four phenolic acid derivatives, four anthocyanins, six flavonoids of quercetin derivatives and two dihydrochalcone phloretin glycosides were identified or characterized among the detected sixteen phenolic compounds.

Direct photothermal techniques for rapid quantification of total anthocyanin content in sour cherry cultivars.

The analytical performance of the newly proposed laser-based photoacoustic spectroscopy (PAS) and of optothermal window (OW) method for quantification of total anthocyanin concentration (TAC) in five sour cherry varieties is compared to that of the spectrophotometry (SP). High performance liquid chromatography (HPLC) was used to identify and quantify specific anthocyanins. Both, PAS and OW are direct methods that unlike SP and HPLC obviate the need for the extraction of analyte. The outcome of the study leads to the conclusion that PAS and OW are both suitable for quick screening of TAC in sour cherries. The correlation between the two methods and SP is linear with R(2)=0.9887 for PAS and R(2)=0.9918 for OW, respectively. Both methods are capable of the rapid determination of TAC in sour cherries without a need for a laborious sample pretreatment.