Tom 23 (2020): Zeszyt 1 (May 2020)

The aim of this work was to determine the polyphenolic profile and the antibacterial properties of extracts from organic pomegranate peel, to evaluate if it could be used as a potential antimicrobial ingredient to elaborated organic food. The antibacterial properties of different organic pomegranate peel extracts (ethyl acetate, acetone and methanol, with an increasing polarity) were tested against: Listeria innocua, Achromobacter denitrificans and Algaligenes faecalis. All extracts showed antimicrobial activity against all bacteria tested except ethyl acetate extract against A. denitrificans. The polyphenolic profile was determined by High Performance Liquid Chromatography (HPLC). Five compounds were identified. Punicagalin was the main component found in acetone and methanol extracts (7,939 µg.g⁻¹ and 5,178 µg.g⁻¹ of lyophilized sample, respectively). Ellagic acid was the main component found in ethyl acetate extract (171 µg.g⁻¹ of lyophilized sample).

The aim of evaluations performed in experimental plantings of the Research and Breeding Institute of Pomology Holovousy Ltd. was to verify the effect of covering systems on fruit characteristics – size, weight, firmness and soluble solids content (SSC). The research was focused on evaluation of fruit characteristics in 2017 and 2018 on fourteen cultivars: ´Amid´, ´Cristiana´, ´Early Korvik´, ´Elza´, ´Fabiola´, ´Felicita´, Horka´, ´Justyna´, ´Kasandra´, ´Kordia´, ´Korvik´, ´Tamara´, ´Těchlovan´ and ´Vanda´. The tested cultivars were grown in an IPM irrigated covered orchard. The largest fruit size was recorded for the cultivar ´Tamara‘ with 29.5 mm followed by the cultivar ´Horka‘ with 29 mm and ´Felicita´ with 28.6 mm. The greatest weight was recorded for the cultivar ´Tamara‘ with 12.4 g followed by ´Felicita´ with 12.3 g. The greatest firmness was recorded in fruits of the cultivar ´Amid´ with index 77.5 and ´Tamara´ with index 73.2. High correlation between fruit characteristics was found only between weight and size of fruits (correlation coefficient 0.88). High differences were recorded between years. In 2017, fruits characteristics were higher (size 27.5 mm, weight 10.9 g, firmness 65.3, SSC 19.3 °Brix) while in 2018, fruit characteristics were lower (size 26.5 mm, weight 9.2 g, firmness 59.2, SSC 16.5 °Brix).

An FNR project entitled “Promotion of Saffron (Crocus sativus L.) cultivation for the profit of arid and semi-arid regions’ women” is led by the CRSTRA. The investigations made during 2013 and 2014 in different arid and semi-arid regions of Algeria have permitted to install Saffron (Crocus sativus L.) cultivation in five principle sites: Ain Zaatout, Beni Souik, Branis, Djemorah and Maafa (Algeria). These mountainous oases are characterised especially by lack of water. After analysing the investigation results, saffron corms were distributed to women to be cultivated. The sowing was realised on different dates. The results obtained in the first year of saffron cultivation in mountainous oases of Algeria are promising. The flowering took place in the same year in four sites; it is the case of Ain Zaatout, Beni Souik, Djemorah and Maafa. However, the flowering took place in the second year in the site of Branis. The difference in saffron flowering occurrence can be attributed to the difference in altitude, the pedo-climatic difference as well as the difference in the date of sowing.

The species complex and infestations of aphids on plum (Prunus persica) and cherry plum (Prunus cerasifera) in Bulgaria were investigated during the period 2013–2018. Nine species from the family Aphididae were found: Brachycaudus helichrysi Kaltenbach (leaf-curling plum aphid), Hyalopterus pruni Geoffroy (mealy plum aphid), Phorodon humuli Schrank (hop aphid), Brachycaudus prunicola Kaltenbach (brown plum aphid), Brachycaudus cardui Linnaeus (thistle aphid), Brachycaudus persicae Passerini (black peach aphid), Rhopalosiphum nymphaeae Linnaeus (waterlily aphid), Aphis spiraecola Patch (spiraea aphid) and Pterochloroides persicae Cholodkovsky (peach trunk aphid). The dominant species on plum are Hyalopterus pruni and Brachycaudus helichrysi. The first species is more widespread and of significantly higher density. The dominant species on cherry plum are Phorodon humuli and B. helichrysi. The species Brachycaudus prunicola is widespread both on plum and cherry plum in Bulgaria. It was found only on twigs, and therefore cannot be considered as a dangerous pest on fruit-bearing plum trees. The other species, some of them described as dangerous pests on plum, are today fairly rare and occur in low density, thus posing no danger to orchards.

The present study evaluated the quality of kiwiberries produced in the territory of the Czech Republic in 2018 and 2019. Actinidia arguta is a very hardy and flexible species which can produce fully ripe fruits even in the setting of moderate climatic zones unlike commercially available A. chinensis as a variety which needs a longer season with higher temperatures to become fully ripe. Once harvested, the fruit was studied for soluble solids content, titratable acidity, antioxidant activity and the content of malic, citric and ascorbic acids. Unlike commercially available kiwifruits, kiwiberries lack hair and can be consumed unpeeled. The results of the present study confirmed the notable potential of kiwiberries consisting namely in the levels of antioxidants present in the skin of the fruit. Kiwiberry fruits feature a higher level of acidity than is common in conventional commercial varieties of A. chinensis as citric acid is the type of acid prevailing in the fruit at all times.

The aim of this study was to identify lactic acid bacteria (LAB) in grapes, must and wines. A total amount of 90 samples including grape (n = 30), must (no = 30) and wine (no = 30) were collected from vineyards in Slovakia. LAB were used cultured on MRS agar with subsequent confirmation with MALDI-TOF mass spectrometry (Bruker Daltonics). Altogether, 904 isolates were identified. Members of the family Lactobacillaeceae were the most abundant in grape (60%), must (46%) and wine (51%). Lactobacillus, Lactococcus, Leuconostoc, Pediococcus and Weissella genera and 27 species of LAB were isolated from the examined samples. Leuconostoc mesenteroides spp. mesenteroides was the most abundant species in grape, must and wine.

In the period 2011–2013 a technological characteristic of the Ukrainian clone Aligote 61-6 was made at the Institute of Viticulture and Enology – Pleven. The Bulgarian candidate-clone Aligote N 10 was used for control. During the grapes ripening, the dynamics of sugar accumulation was monitored. Upon technological maturity the indicators of the yields were accounted and mechanical analysis was performed. The chemical composition of the must, the obtained wines and their organoleptic qualities were analyzed. In its mechanical composition, Aligote 61-6 was typically wine one and it did not differ significantly in the texture and structure of the cluster and berry from the control. The theoretical yield of both clones was high. They exhibited good sugar accumulation and similar acid content. Grapes from the control had better technological indicators for obtaining wines of optimal chemical composition and quality. In the 2011 and 2013 vintages, the control wines exceeded those of the Ukrainian clone in terms of sugar-free extract content. The experimental wines Aligote N 10 had higher titratable acidity compared to the Ukrainian clone. The difference in the phenolic substances ratio and the colour intensity in the samples from both clones were insignificant. The control wines were superior in their organoleptic qualities to those of the Ukrainian clone.

Vitis vinifera L. is adapted to a very variable range of climates but it mostly grows in the temperate regions of continental Europe. In the Slovak Republic, the Tokaj wine region is one of the territories, where wine production is concentrated. Grape is a popular fruit and when processed, it is used as musts, juices or wine. Some people may suffer from allergic reactions to grapes. Up to now, endochitinases, lipid-transfer protein, and thaumatin were identified as grape allergens. In this study, expression of chitinase and thaumatin allergen was analysed in the grapes of Tokaj region varieties – Hachat Lovelin, Tokay and Muskat Blanc. Expression changes were calculated by the delta delta Ct method. Expression differences of chitinase were found to be similar in these varieties. Thaumatin was found to be variable in its transcription.

The ribosomal-depleted total RNA from white-berry grapevine (Vitis vinifera, SK933) plant showing severe chlorosis and downrolling of leaves was used for the high-throughput sequencing (HTS) analysis in order to unravel the potential contribution of the viral pathogens to the symptomatology observed. The combination of de novo assembly and mapping of ca. 1.1 millions of HTS reads enabled to identify and characterise a complex viral/viroid infection involving Grapevine leafroll-associated virus-2 (GLRaV-2), Grapevine leafroll-associated virus-3 (GLRaV-3), Grapevine rupestris stem pitting-associated virus (GRSPaV), Grapevine rupestris vein feathering virus (GRVFV), Grapevine Syrah virus-1 (GSyV-1) and Hop stunt viroid (HSVd). The determined nearly complete genomes of GLRaV-2 SK933 showed its high genetic divergence from previously characterised isolates. In case of GRSPaV, two variants representing different evolutionary lineages have been identified in the plant. The results further pinpoint the complexity of grapevine viral diseases and show that mixed virus infection of grapevine is rather a rule than an exception.

Anthocyanins are plant dyes responsible for the colour of red wine. Of these, malvidin-3-glucoside is the most significant member and its content was monitored in wines that were first left to age in oak barrels for 12 months, subsequently bottled and sealed with plastic/cork stoppers. The malvidin-3-glucoside content was also studied in the same wines that were bottled right away without aging in barrels. Analyses were conducted within the time spans of 3 to 30 months. The highest malvidin-3-glucoside concentrations were found in month 3 of the aging process, and they significantly decreased in month 6 and month 15 of storing. Between month 15 and month 30 of storing, the content of malvidin-3-glucoside basically remained unchanged. The results of the measurements show that to preserve higher malvidin-3-glucoside levels for longer periods of time, it is better to store wine in barrels rather than in bottles and when a bottle is used instead of a barrel, a plastic stopper is better than a cork stopper.

Potato is a temperate crop greately adapted to tropical climate as evidenced by the greater share of production by the tropical countries in recent years. It is grown mainly during rainy seasons coupled with long summers in majority of potato growing countries. However, the sub-tropics country like India, kharif (or) rainy season potatoes is still an underexploited segment which is mainly restricted to hills and plateaus, but not plains. Unlike short day crops grown during winter, the yield of kharif potato is far lower. However, the simulation model estimated the attainable yield could be enhanced substantially by extending canopy cover (100%) duration from 10 to and 40 days over the existing window of favourable growing period at various kharif growing areas. Accordingly, the yield could be enhanced from 25.4 to 34.7 t.ha⁻¹ in plateaus (Dharwad), and from 31.9 to 42.0 t.ha⁻¹ in Northern HH (Shimla). The South and Northern HH locations (Ooty and Shimla respectively) registered a higher attainable yield (45.1 and 42.0 t.ha⁻¹, respectively) which strongly indicates the necessity of trait specific improvement program for developing better phenotype combination having high water, radiation and light use efficiency for enhanced yield potential.

A study was carried out at the Federal University of Agriculture Abeokuta, Nigeria to determine the gene action underlying the inheritance of important agronomic traits as well as the general combining ability (GCA) and specific combining ability (SCA) of the parents and hybrids, respectively. Ten hybrids were developed by crossing five lines to two testers. The hybrids and parents were evaluated on the field in a randomised complete block design replicated three times, and data were collected on days to 50% flowering, number of branches, stem diameter, plant height, pod length, pod width, pod weight, number of pods and pod yield. The data were subjected to line by tester analysis and results showed substantial variability among the genotypes for some of the characters measured. Days to 50% flowering, number of pods and pod yield were largely under additive gene action while non-additive gene action was more important in the inheritance of plant height. Favourable GCA and SCA effects for days to 50% flowering were observed in NGB00356, NGB00326 and NGB00347 × NGB00326, respectively. The tester NGB00326 had a positive and significant GCA effect for number of pods while the highest positive SCA effect for pod yield was found in NGB00297 × NGB00326. Thus, NGB00356 and NGB00326 could be considered as sources of alleles for development of early maturing while the cross NGB00297 × NGB00326 could be exploited for high yielding okra genotypes.