Antifungal activity of indigenous bacillus sp. isolate Q3 against marshmallow mycobiota

Marshmallow is a host of a number of saprophytic and parasitic fungi in Serbia. The seeds of marshmallow are contaminated with fungi from different genera, especially Alternaria and Fusarium, which significantly reduced seed germination and caused seedling decay. In this study we investigate antagnonism of indigenous Bacillus sp. isolate Q3 against marshmallow mycopopulation. Bacillus sp. Q3 was isolated from maize rhizosphere, characterized by polyphasic approch and tested for plant growth promoting treats. Bacillus sp. Q3 produced antifungal metabolites with growth inhibition activity against numerous fungi in dual culture: 61.8% of Alternaria alternata, 74.8% of Myrothecium verrucaria and 33.6% of Sclerotinia sclerotiorum. That effect could be caused by different antifungal metabolites including siderophores, hydrolytic enzymes, organic acids and indole acetic acid (IAA). Suppression of natural marshmallow seed infection by Q3 isolate was observed. The seeds were immersed in different concentrations of bacterial suspension during 2h and their infections by phytopathogenic fungi were estimated. The results showed significant reduction of seed infection by Alternaria spp. The presented results indicate possible application of this isolate as promising biological agent for control of marshmallow seed pathogenic fungi

The genomic history of southeastern Europe

Farming was first introduced to Europe in the mid-seventh millennium BC, and was associated with migrants from Anatolia who settled in the southeast before spreading throughout Europe. Here, to understand the dynamics of this process, we analysed genome-wide ancient DNA data from 225 individuals who lived in southeastern Europe and surrounding regions between 12000 and 500 BC. We document a west-east cline of ancestry in indigenous hunter-gatherers and, in eastern Europe, the early stages in the formation of Bronze Age steppe ancestry. We show that the first farmers of northern and western Europe dispersed through southeastern Europe with limited hunter-gatherer admixture, but that some early groups in the southeast mixed extensively with hunter-gatherers without the sex-biased admixture that prevailed later in the north and west. We also show that southeastern Europe continued to be a nexus between east and west after the arrival of farmers, with intermittent genetic contact with steppe populations occurring up to 2,000 years earlier than the migrations from the steppe that ultimately replaced much of the population of northern Europe

Istorijski razvoj biljne virusologije u Srbiji

Neprestani demografski rast sveta i potreba da se stanovništvo snabde prirodnim proizvodima i hranom kontrolisanog kvaliteta, nametnuli su potrebu proučavanja virusnih bolesti biljaka. Osim praktičnog značaja u razvijanju uspešnih strategija u suzbijanju virusa i sprečavanju ili umanjenju šteta izazvanih virusima, biljna virusologija ima i veliki fundamentalni značaj u otkrivanju bioloških, epidemioloških i evolutivnih zakonitosti i pojava. Otkriće biljnih virusa vezuje se za 1898. godinu kada je Martinus Willem Beijerinck proučavajući mozak duvana ukazao na novi svet infektivnih agenasa („contagium vivum fluidum“). U Srbiji tridesetih godina prošlog veka, proučavanja biljnih virusa započela su naučnim radom Mladena Josifovića na šarki šljive. Posle Drugog svetskog rata, Dragoljub Šutić, Veljko Nikolić i Mitar Jordović uvode naučne eksperimentalne metode u istraživanja viroza, i time postavljaju temelje razvoja proučavanja biljnih virusa kod nas. Razvoj virusologije u Srbiji, kao i u većini zemalja, obuhvatao je nekoliko faza: početnu deskriptivnu (otkrivanje i opisivanje brojnih viroza), potom epidemiološku (proučavanje načina održavanja i širenja virusa), fizičko-hemijsku (proučavanje morfoloških osobina i hemijskog sastava virusa), molekularno-biološku fazu (razumevanje strukture i funkcije genoma virusa, mehanizama replikacije, unapređenje starih i uvođenje novih metoda detekcije i identifikacije virusa i njihovih sojeva, pravilna taksonomija virusa u skladu sa poreklom i evolutivnim međuodnosima). Baveći se različitim oblastima biljne virusologije u proteklih gotovo osam decenija, brojni virusolozi ostvarili su značajna dostignuća. Posebne zasluge za razvoj biljne virusologije svakako pripadaju Dragoljubu Šutiću, koji je zahvaljujući svom širokim obrazovanju, uspešnom eksperimetalnom radu, dobro razvijenoj domaćoj i međunarodnoj saradnji, ostvarenim rezultatima i brojnim naučnim radovima i publikacijama, značajno doprineo obrazovanju mnogih generacija studenata, i dao nemerljiv doprinos unapređenju zdravlja bilja. Razvoj biljne virusologije u našoj zemlji nije zavisio samo od opšteg napretka ove nauke u svetu, već u velikoj meri i od uslova za razvoj naučnih istraživanja. I pored relativno skromnih uslova koji vladaju na naučno-istraživačkoj sceni virusologije, rad biljnih virusologa u proteklom periodu podigao je kvalitet istraživanja trudeći se da dostigne i ne zaostaje za kvalitetom razvijenih zemalja. Značajno iskustvo u decenijskom radu u oblasti razvojnih i primenjenih istraživanja u biljnoj virusologiji i sva stečena saznanja o biljnim virusima bila su, i sada su od neprocenjivog značaja za poljoprivredne proizvođače i unapređenje njihove proizvodnje, za unapređenje sistema i efikasnosti karantinske i fitosanitarne službe, rad ovlašćenih dijagnostičkih laboratorija, ispunjavanje međunarodnih fitosanitarnih zahteva u prometu i razmeni biljnog materijala, i podizanju ugleda Srbije. Većina publikacija je rezultat istraživanja etiologije, simptomatologije, epidemiologije, genetičke strukture populacije, otpornosti prema virusima i drugih mera kontrole sa ciljem iznalaženja rešenja od praktičnog značaja. Iako je razvoj biljne virusologije u Srbiji pokrio mnoge fundamentalne i praktične aspekte ove nauke, očekuju se nastavak istraživanja zasnovanih na mogućnostima koja nam pružaju druge nauke, pre svega molekularna biologija i bioinformatika. Zalog za sigurnu budućnost virusologije u našoj zemlji je obrazovanje i osposobljavanje mladih istraživača

Biochemical changes in Oenothera biennis plants infected by 'Candidatus Phytoplasma solani'

The aim of the present paper was to study the response of Oenothera biennis L. to 'Candidatus Phytoplasma solani' (Stolbur) infection by analyzing total sugars, polyphenols, photosynthetic pigments content and the antioxidant capacity in leaves and roots of healthy and infected plants. The infection caused a significant increase in peroxidation of lipids, phenylalanine ammonia-lyase activity, total sugar, polyphenols and anthocyanins content (2.8, 2.6, 1.8, 1.4, 6.8 fold, respectively), as well as a decrease in photosynthetic pigments (2-6 fold) and total flavonoids (1.5 fold) in the leaves of Oe. biennis. Changes in these parameters were insignificant in the roots except for the total polyphenols content that was 2.7 times higher in the infected ones. Reduced gluthatione content in both tested organs was not affected by the infection (3.7 and 1.7 mu mol/g fresh weight of leaves and roots, respectively). The elevated content of total sugars, flavonoids and polyphenols, as well as the reduction of photosynthetic pigments and anthocyanins in infected plants are indicative of changes in the metabolism of Oe. biennis affected by the Stolbur phytoplasma. In addition to reduction of chlorophyll and carotenoids, the phytoplasma accelerated leaf senescence. Plants responded to the infection via enhanced superoxide anion scavenging, even though this reaction did not prevent, apparently, membrane damage in analysed leaves. This investigation presents new data on the effect of a phytoplasma infection on its host

The Incidence and Genetic Diversity of Potato virus S in Serbian Seed Potato Crops

It is essential that certified potatoes are free from known viruses which can negatively affect quality and yield. However, very little is known about the distribution and frequency of Potato virus S (PVS) in Serbia. Until 2014, PVS was present sporadically in the domestic seed potato production. The incidence of PVS was studied by a molecular method over 3 years (2014-2016) in four important potato-growing regions (Moravidd. Zlatiborski, Raski and Macvanski) and in different cultivars. The results showed that the incidence of PVS increased steadily over 3 years from 1.52 to 8.84%. The Moravicki region had the highest incidence (13.06%) and Desiree was the most susceptible cultivar with a mean PVS incidence of 8.2% followed by Marabel and Riviera. The highest significant statistical difference was between the cultivars and in the interaction between cultivars and regions. A detailed phylogenic analysis of the tested isolates contained that Serbian PVS belongs to PVSO. Of the 18 Serbian PVS isolates included in this study, eight were grouped into the PVSO cluster and formed a subgroup (O-I) with isolates from the USA, Syria, Korea and Chile. Ten Serbian isolates of PVS together with the isolates from Iran were clustered in a branch of subgroup O-VII. This study constitutes the fast report of PVS isolates in Serbia which are capable of infecting Chenopodium quinoa and inducing the symptoms of local chlorotic lesions

Social and genetic diversity in first farmers of central Europe

The Linearbandkeramik (LBK) Neolithic communities were the first to spread farming across large parts of Europe. We report genome-wide data for 250 individuals: 178 individuals from whole-cemetery surveys of the Alföld Linearbankeramik Culture eastern LBK site of Polgár-Ferenci-hát, the western LBK site of Nitra Horné Krškany and the western LBK settlement and massacre site of Asparn-Schletz, as well as 48 LBK individuals from 16 other sites and 24 earlier Körös and Starčevo individuals from 17 more sites. Here we show a systematically higher percentage of western hunter-gatherer ancestry in eastern than in western LBK sites, showing that these two distinct LBK groups had different genetic trajectories. We find evidence for patrilocality, with more structure across sites in the male than in the female lines and a higher rate of within-site relatives for males. At Asparn-Schletz we find almost no relatives, showing that the massacred individuals were from a large population, not a small community

Streamlining Global Germplasm Exchange: Integrating Scientific Rigor and Common Sense to Exclude Phantom Agents from Regulation

This collaborative work by over 180 researchers from 40+ countries addresses the challenges posed by "phantom agents"-putative pathogenic agents named in literature without supporting data on their existence. Those agents remain on regulatory lists, creating barriers in trade and plant certification. Historically identified based solely on symptoms, these agents lack isolates or sequence data, making reliable detection or risk assessment impossible. After reviewing over 120 such agents across 10 key plant genera, we recommend their removal from regulatory lists and call for revised standards aligned with phytomodern diagnostics. This effort seeks to streamline germplasm exchange, benefiting global agriculture by removing the constraints imposed by phantoms

Streamlining global germplasm exchange: Integrating scientific rigor and common sense to exclude phantom agents from regulation

This collaborative work by over 180 researchers from 40+ countries addresses the challenges posed by “phantom agents”-putative pathogenic agents named in literature without supporting data on their existence. Those agents remain on regulatory lists, creating barriers in trade and plant certification. Historically identified based solely on symptoms, these agents lack isolates or sequence data, making reliable detection or risk assessment impossible. After reviewing over 120 such agents across 10 key plant genera, we recommend their removal from regulatory lists and call for revised standards aligned with modern diagnostics. This effort seeks to streamline germplasm exchange, benefiting global agriculture by removing the constraints imposed by phantoms