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Discovery of new autochthonous grape varieties in Khenchela (North-East Algeria), using molecular markers and morphological characteristics
Full text link In the current study, both molecular and morphological approaches are used to comprehensively characterize 31 grapevine varieties from different localities in the province of Khenchela (Northeastern Algeria). The aim is to create a detailed inventory that provides a systematic overview of their diversity and geographical distribution. To achieve this objective, genetic analysis was conducted based on twelve highly polymorphic microsatellite loci, resulting in 13 distinct molecular profiles. Among these, varieties such as ‘Chikki’, ‘Bezoul El Khadem d’Algérie’, and three new varieties specific to the Khenchela region were identified. The ampelographic study was conducted using a set of 18 ampelometric descriptors established by the Office International de la Vigne et du Vin (OIV), focusing on leaf characteristics. Principal component analysis was used to identify the 15 most discriminating descriptors, notably the length of veins (OIV-601, OIV-602, OIV-603, OIV-604, OIV-611) and the angles between them (OIV-607, OIV-608), as well as the length and width of the teeth (OIV-613, OIV-614, OIV-615) and the opening of the petiolar sinus (OIV-618). The combination of molecular markers and ampelometric descriptors enables precise identification of vine varieties, a better understanding of regional diversity, and effective conservation and preservation of valuable genetic resources
First insights on barley as banker plant for Rhopalosiphum maidis to enhance Diaeretiella rapae in white cabbage
Full text link „Banker Plant“-Systeme sind ein gängiges Mittel im integrierten Pflanzenschutz in Gewächshauskulturen, aber es gibt nur wenig Forschung im Freilandgemüseanbau. Daher wurden in zwei Jahren Kleinparzellenversuche im Freiland-Weißkohl durchgeführt, in denen das Potenzial von Gerste-Banker Plants mit alternativen Blattlauswirten (Rhopalosiphum maidis L.) auf die Parasitierung von Blattläusen am Kohl untersucht wurden. Im Jahr 2022 wurden drei Gerste-Varianten mit einer Kontrolle verglichen: Gerste ohne Blattlausbesatz, Gerste mit R. maidis und Gerste mit R. maidis, welche durch den Parasitoid Diaeretiella rapae (M’Intosh) parasitiert wurde. Im Jahr 2023 wurde die nur die zweite Gerste-Variante mit der Kontrolle verglichen. Alle Gerste-Varianten reduzierten die Blattlauszahlen in Kohl signifikant, hatten jedoch keinen Einfluss auf die Parasitierung. Dennoch wurde im Freiland eine Entwicklung von D. rapae auf R. maidis beobachtet, und das Testsystem sollte in einem größerem Maßstab überprüft werden.Banker plants are a common tool in integrated pest management for greenhouse crops, but limited research has been conducted on their use in open-field vegetable production. Therefore, we aimed to evaluate the potential of barley banker plants with alternative aphid hosts (Rhopalosiphum maidis Linnaeus) for promoting aphid parasitism in field-grown white cabbage in central Germany.
In 2022, we compared control plots with three treatments involving barley sown between crop rows: barley alone, barley infested with R. maidis, and barley infested with R. maidis parasitised by Diaeretiella rapae (M\u27Intosh). In 2023, only barley infested with R. maidis was compared to the control. All barley treatments significantly reduced aphid numbers but did not affect parasitism rates in cabbage. However, the development of D. rapae on R. maidis was observed in the field. Due to study limitations, the system should be re-evaluated under controlled conditions in field cages and at larger scales
Rootstocks as factors influencing the fruit quality and antioxidant activityof ‘Grace Star’ sweet cherry
Full text linkDie Wirkung von 14 Unterlagen auf die Fruchtqualität und das antioxidative Potenzial der Süßkirsche ‘Grace Star’ wurde im fünften und sechsten Jahr nach der Pflanzung untersucht. Das Experiment wurde im Dorf Prislonica (Čačak, Serbien) auf schwerem, flachem und saurem Boden durchgeführt. Die Ergebnisse zeigten, dass die Wurzelstöcke einen signifikanten Einfluss auf alle getesteten Eigenschaften hatten. Abgesehen davon hatten, mit einigen Ausnahmen, das Jahr allein und die Interaktion Unterlagen x Jahr einen signifikanten Einfluss. Bei den Unterlagen führten ‘Cigančica’- und Myrobalan-Setzlinge gleichzeitig sowie ‘Cigančica’ allein zu den höchsten FW, SW, W, T und Dg, während ‘Oblačinska’, Krymsk 6, Adara und Myrobalan die höchsten FRa-Werte verursachten. Myrobalan förderte die besten L und Mahaleb die höchsten φ und RI; die Früchte von PHL-A enthielten die höchsten TAc, TPC und TFC. Gisela 6 förderte die schwächste antioxidative Aktivität, die beste wurde jedoch bei Früchten von PHL-C und ‘Cigančica’ beobachtet. Die SSC war bei Früchten von Bäumen, die auf Mahaleb, Colt, PHL-A, Gisela 5 und ‘Oblačinska’ gepfropft waren, am höchsten, während PHL-C die niedrigste hervorrief. Die höchste TA wurde ohne signifikante Unterschiede auf Adara und Myrobalan verzeichnet und die niedrigste auf Mahaleb, PHL-C und ‘Oblačinska’, ebenfalls ohne Unterschiede zwischen ihnen. Kirschen von Bäumen, die auf die belebenden Sorten Mazzard und Mahaleb sowie die halbzwergartige PHL-A gepfropft waren, zeigten den höchsten Aschegehalt, während der niedrigste auf Gisela 6 beobachtet wurde. PHL-A neigte dazu, die niedrigsten FW, FRa, Fruchtabmessungen, -größe und SL hervorzurufen; Adara induzierte den niedrigsten φ-Wert und pH-Saft, während ‘Cigančica’, Myrobalan und Adara ähnliche und die niedrigsten RI-Werte verursachten. Im zweiten Jahr wurden höhere FW-, SL-, SSC-, TA-, Asche-, TPC- und TFC-Werte beobachtet, während Fruchtgröße, Dg, φ und pH-Saft im ersten Versuchsjahr höher waren. Es gab signifikante Korrelationen zwischen TPC, TFC und antioxidativer Aktivität sowie zwischen TAc und antioxidativer Aktivität. Schließlich verbesserten kräftigere und weniger ertragreiche Unterlagen die physikalischen Eigenschaften der Früchte, während weniger kräftige Unterlagen die chemischen Eigenschaften der Früchte verbesserten.The effect of 14 rootstocks on fruit quality and antioxidant potential of ‘Grace Star’ sweet cherry was studied during 5th and 6th year after planting. The experiment was performed in the Prislonica vilage (Čačak, Serbia), on a heavy, shallow and acidic soil. The results showed that rootstocks had a significant effect on all tested properties. Apart from them, a significant influence, with some exceptions, was exerted by year alone and interaction rootstock × year. With regard rootstocks, ‘Cigančica’ and Myrobalan seedlings simultaneously and ‘Cigančica’ alone induced the highest FW, SW, W, T and Dg respectively, whereas ‘Oblačinska’, Krymsk 6, Adara and Myrobalan caused the highest FRa values. Myrobalan promoted the best L and Mahaleb the highest φ and RI; fruits from PHL-A contained the highest TAc, TPC and TFC. Gisela 6 promoted the weakest antioxidant activity, whereas the best was observed in fruits from PHL-C and ‘Cigančica’. The SSC was the highest in fruit from trees grafted on Mahaleb, Colt, PHL-A, Gisela 5 and ‘Oblačinska’, whereas PHL-C induced the lowest. The highest TA was recorded on Adara and Myrobalan with no significant differences between them, and the lowest on Mahaleb, PHL-C and ‘Oblačinska’ also without differences between them. Cherries of trees grafted on invigorating Mazzard and Mahaleb and semi-dwarfing PHL-A showed the highest ash content whereas the lowest was observed on Gisela 6. The PHL-A tended to induce the lowest FW, FRa, fruit dimensions, its size and SL; Adara induced the lowest φ value and pH juice, whereas ‘Cigančica’, Myrobalan and Adara caused similar and the lowest RI values. Regarding years, higher FW, SL, SSC, TA, ash content, TPC and TFC was observed in second year, whereas fruit dimensions, Dg, φ and pH juice was higher in first year of trial. There were significant correlations between TPC, TFC and antioxidant activity, as well as between the TAc and antioxidant activity. Finally, more vigorous rootstocks and less yielding rootstocks improved fruit physical attributes, whereas less vigorous rootstocks increased fruit chemical properties
Micro-morphological traits of Aglaonema griffithii and its chemical and antioxidant properties
Full text linkAglaonema griffithii Schott is a helophytic plant widely found in the southern Vietnam and some regions of southeastern Asia. The aim of this study is to provide the anatomical characteristics, chemical compounds and antioxidant activity of this species for the first time. The micro-morphological traits of the studied species are performed using the iodine green-carmine double staining method. The anatomical characteristics of the different parts of A. griffithii are used as a monograph in the herbal medicine standardization of this plant. The gas chromatography/mass spectrometry assay is also used to determine the chemical compounds in the ethanolic extracts obtained from A. griffithii. Of these, sucrose is the most abundant component found in the rhizome and petiole extracts while the leaf extract is found to be rich in phytol as the highest percent component. The antioxidant properties of the ethanol extracts of the A. griffithii leaf, rhizome, and petiole were also investigated using DPPH radical scavenging assay with IC50 values of 193.08, 234.61, and 270.65 μg/mL, respectively
Effects of drought and heat stresses on physiological and yield traits of maize landraces in Mexico
Full text linkDrought and heat stress are major constraints for crop productivity worldwide. Maize is the most important crop in Mexico contributing to food security. Maize landraces in Mexico exhibit remarkable diversity and most farmers continue to cultivate them. The present study investigated the effects of combined drought and heat stress on the physiological and yield responses of maize landraces in Mexico. Six maize landraces and two improved varieties were evaluated. Two treatments were used: a well-watered control and drought stress, applied at the reproductive stage for 20 days. Maize physiological and yield responses were analyzed by one-way ANOVA. Five drought tolerance indices were calculated and multivariate analyses were used to classify drought-tolerant from sensitive maize genotypes. Drought and heat stress reduced the photosynthetic rate (Pn), stomatal conductance (gs), transpiration (Tr), and increased water use efficiency (WUE) compared to well-watered plants. Yield under drought conditions was 46% lower than under irrigation conditions and yield losses were caused mainly by a significant reduction in ear and kernel weights. Multivariate analyses identified the maize genotypes XNM, SB, and CHTZ as drought-tolerant. Tolerant varieties help farmers mitigate climate challenges and sustain food supply. Moreover, local maize landraces offer the potential for discovering valuable tolerance traits
Genetic analysis and construction of a genetic map of Russian Dandelion (Taraxacum koksaghyz) as an alternative resource crop for natural rubber
No full textDie globale Naturkautschuk-Versorgung ist momentan von einer einzigen Art (Hevea brasiliensis) abhängig, was sie anfällig für Krankheiten und wirtschaftlichen Druck macht. Diese Dissertation begegnet dem dringenden Bedarf an alternativen Kautschukquellen durch die genetische Verbesserung des Russischen Löwenzahns (Taraxacum kok-saghyz, TKS), einer vielversprechenden Pflanze für gemäßigte Zonen. Hauptziel war die Entwicklung genomischer Werkzeuge zur Beschleunigung der Züchtung ertragreicher TKS-Sorten.
Zunächst wurde die genetische Diversität von TKS und anderen Taraxacum-Arten mittels AFLP-Marker analysiert. Die Ergebnisse bestätigten die genetische Abgrenzung von TKS gegenüber verwandten Arten wie dem gewöhnlichen Löwenzahn, zeigten aber auch nur eine geringe bis mäßige genetische Vielfalt im bestehenden Zuchtmaterial auf. Dies verdeutlicht die Notwendigkeit, strategisch neues pflanzengenetisches Material zu integrieren, um einen langfristigen Zuchterfolg zu sichern.
Eine biparentale F1-Kartierungspopulation, erzeugt aus Kreuzungen von Eltern mit hohem und niedrigem Kautschukgehalt, wurde in mehrjährigen Feldversuchen an drei Standorten untersucht. Dabei zeigte sich eine enorme phänotypische Variation des Kautschukgehalts (0,1 % bis 24 %). Die hohe Heritabilität des Merkmals ( = 0,656) belegt eine starke genetische Kontrolle und signalisiert ein hohes Potenzial für die züchterische Selektion.
Im Kern dieser Arbeit stand die Erstellung der ersten hochauflösenden genetischen Karten für TKS mittels Genotyping-by-Sequencing (GBS). Es entstanden zwei detaillierte elterliche Karten mit jeweils acht Kopplungsgruppen, entsprechend der haploiden Chromosomenzahl von TKS. Diese Karten bildeten die Grundlage für die Analyse von Quantitative Trait Loci (QTL), um die für die Kautschukproduktion verantwortlichen Genomregionen zu identifizieren.
Die Analyse identifizierte drei statistisch signifikante Major-QTL für den Kautschukgehalt. Zwei davon lagen auf der mütterlichen und einer auf der väterlichen Karte. Die einzelnen Loci erklärten zwischen 9,1 % und 15,4 % der phänotypischen Varianz. Ein Abgleich mit dem physischen Genom bestätigte eine bekannte QTL-Region auf Chromosom A1 und identifizierte darüber hinaus eine bisher unbekannte QTL-Region auf Chromosom A7.
Zusammenfassend liefert diese Forschung entscheidende genomische Werkzeuge für die TKS-Züchtung. Die hochauflösenden Karten und identifizierten QTL sind eine fundamentale Ressource für die moderne Züchtung. Die mit den QTL verknüpften SNP-Marker ermöglichen die Entwicklung von Werkzeugen für die markergestützte Selektion (MAS). Damit können Züchter überlegene Pflanzen bereits im Keimlingsstadium identifizieren, was die Entwicklung kommerziell rentabler TKS-Sorten erheblich beschleunigt und zur Sicherung einer nachhaltigen Naturkautschuk-Versorgung beiträgt.The global supply of natural rubber is critically dependent on a single species, Hevea brasiliensis, leaving it vulnerable to disease and economic pressures. This dissertation addresses the urgent need for alternative rubber sources by focusing on the genetic improvement of Russian Dandelion (Taraxacum kok-saghyz, TKS), a promising temperate-climate resource crop. The primary goal was to develop genomic tools to accelerate the breeding of high-yielding TKS varieties.
To achieve this, the study first assessed the genetic landscape of TKS and related species. Using Amplified Fragment Length Polymorphism (AFLP) markers, the research confirmed that TKS is genetically distinct from related species like the common dandelion, while also revealing low to moderate genetic diversity within existing breeding germplasm. This highlights a need to strategically incorporate new genetic material to ensure long-term breeding success.
A biparental F1 mapping population was created by crossing high and low rubber-producing parent plants. Extensive multi-year field trials across three different locations revealed significant phenotypic variation for rubber content, ranging from 0.1 % to 24 %. A high broad-sense heritability ( ) of 0.656 was calculated for this trait, indicating strong genetic control and a high potential for improvement through selective breeding.
The core of the project involved creating the first high-resolution genetic maps for TKS using Genotyping-by-Sequencing (GBS). This resulted in two detailed parental maps. Each resolved into eight linkage groups corresponding to the haploid chromosome number of TKS. These maps served as the foundation for quantitative trait loci (QTL) analysis to identify genomic regions controlling rubber production.
The analysis successfully identified three major, statistically significant QTL associated with rubber content. Two QTL were located on the maternal map and one on the paternal map, with individual loci explaining between 9.1 % and 15.4 % of the phenotypic variance. By aligning these genetic findings with the TKS physical genome, the study confirmed a previously reported major QTL region on chromosome A1 and discovered a novel major QTL on chromosome A7.
In conclusion, this research provides a vital genomic toolkit for TKS improvement. The high-resolution maps and identified QTL for rubber content are foundational resources for modern breeding. The SNP markers linked to these QTL can now be used to develop tools for marker-assisted selection (MAS), enabling breeders to identify superior plants at an early stage, thereby accelerating the development of commercially viable TKS cultivars and helping to secure a sustainable future for natural rubber
Grapevine axillary meristems coordinate inner energy depletion and vascular tissue synthesis during budbreak: Utilization of reserves and xylem appearing during budbreak
Full text linkBud dormancy in woody perennials is a complex physiological process regulated by seasonal environmental fluctuations. Both water status and energy reserve molecules are involved in the process of bud dormancy release, although their precise roles remain a subject of ongoing debate. This study aimed to investigate the role of energy reserve molecules and the formation of vascular tissue in the grapevine during and after budbreak. Histochemical, microscopy, and biochemical techniques were employed to monitor the pattern of vascular tissue formation in the bud meristem and surrounding cane tissues, as well as the utilisation of reserve molecules, such as starch. Our findings revealed that starch reserves were rapidly consumed, a process associated with increased alpha-amylase activity. Furthermore, we observed the formation of new vascular tissues starting from the onset of budbreak until stage EL7, at which point functional connections between the emerging shoot and cane were established, ensuring the initiation of water transport
Equal distance sowing enhances soybean (Glycine max (L.) Merr.) growth and competitiveness against weeds
Full text linkDespite advances in cultivation strategies, significant yield losses caused by weed infestation remain a major problem in the cultivation of soybean (Glycine max (L.) Merr.). As pesticide use is increasingly questioned, sustainable integrative weed management strategies are gaining attention. A two-year pesticide-free field experiment was conducted at the University of Hohenheim to investigate whether equal distance sowing (EDS), characterized by a triangular sowing pattern with narrow row distance (0.15 m), improves soybean growth and promotes natural crop competitiveness against weeds. Two early-maturing cultivars were tested in EDS and conventional normal distance sowing (NDS, 0.50 m) under both weed-free and weedy conditions. Soybeans grown under EDS exhibited higher early-season competitiveness against weed infestation, attributed to enhanced light interception and accelerated soil cover. Seed yields across all treatments were reduced by weed infestation. Overall, the findings suggest that EDS is a promising strategy for sustainable soybean cultivation within an integrated weed management approach
The effect of drought stress on Pinellia ternata in terms of physiology and aquaporin genes after Arbuscular mycorrhizal fungal inoculation
Full text linkPinellia ternata (P. ternata) is a traditional Chinese herbal medicine. Arbuscular mycorrhizal fungi (AMF) establish symbiosis with plants, which is essential in improving mineral nutrient acquisition and drought resistance of host plants. This study used the medicinal plant P. ternata as the experimental material to investigate the similarities and differences in photosynthesis, osmotic regulation, and antioxidant activity between arbuscular mycorrhizal and non-arbuscular mycorrhizal plants under drought stress. The results showed that AMF inoculation could significantly increase the photosynthetic rate (Pn), stomatal conductance (Gs), and transpiration rate (Tr) of P. ternata. Under drought stress, P. ternata adapted to drought by accumulating osmotic regulatory substances such as proline and soluble proteins and increasing chlorophyll content. In addition, Mycorrhizal P. ternata also exhibited high activities of peroxidase, superoxide dismutase, and catalase under drought conditions, improving the response of the antioxidant system. AMF could promote the growth and development of P. ternata under drought stress. Mycorrhization upregulated the expression of PtTIP, NIP, and PIP genes under drought stress. AMF can alleviate drought stress-induced damage by regulating photosynthetic capacity, osmosis, antioxidant activities, and aquaporin gene expression. Our study highlights the effect of AMF on P. ternata under drought stress by mediating physiological and biochemical activities