In order to elucidate genetic control of Verticillium wilt (VW) resistance in hop, an F1 mapping population derived from a cross of cultivar Wye Target, with a predicted genetic basis of resistance, and susceptible male breeding line BL2/1 was developed to assess wilting symptoms and to perform QTL mapping. The genetic linkage maps, constructed with 203 previously developed markers and using a pseudotestcross strategy, formed ten major linkage groups (LG) of the maternal and paternal maps. A significant QTL for VW resistance was detected at LOD 7 on a single chromosomal region on LG03 of both parental maps, accounting for 24.2–26.0 % of the phenotypic variance. This is the first QTL identified for resistance to VW in hop. QTLs for alpha acid content and yield parameters were also detected and confirmed our previously detected QTLs in a different pedigree and environment. The work provides the basis for exploration of QTL flanking markers for possible use in marker assisted selection.
COBISS.SI-ID: 7466361
The University of Ljubljana, principal investigator B. Javornik, coordinated the 7.FP project see.era.net.plus »Towards the preservation of autochthonous grapevine (Vitis vinifera L.) varieties in West Balkan countries«. The project lasted two years and included partners from Serbia, Bosnia and Herzegovina and Macedonia. The project, which was co-financed by the progamme, involved the collection and DNA fingerprinting of autochthonous grapevine varieties in the region of the Western Balkans. We collected 196 grapevine samples, which resulted in 125 unique genotypes on the basis of fingerprints obtained by 22 microsatellite markers. A user-friendly database (http://vitis.atcglabs.com/) of fingerprinted genotypes was set up and it is publicly accessible. We further studied the genetic structure and relationship among genotypes, evaluated their pedegrees, synonyms and homonyms and the entire gene pool was compared with the world collection of grapevine genotypes. The grapevine genotypes from the Western Balkans, which had been neglected in world collections, are now decribed for the first time on an internationally comparable level and can be further explored for grapevine selection and breeding.
COBISS.SI-ID: 7753593
In this work, we analyzed proteomic profile of hop roots in control and fungus-infected plants in three time points. Responses of susceptible and resistant cultivar were then compared. The profile changed between time points significantly also in control plants, therefore the influences of infection and time were separated using appropriate statistic methods. We found out that infection caused significant quantitative changes in more than a fifth of detectable proteome in susceptible cultivar, while there were no changes in resistant cultivar. Mass spectrometry was used to identify 100 protein spots. As expected, increased production of defence proteins was found in susceptible cultivar, whereas specific forms of a lectin potentially involved in pathogen recognition were identified in resistant cultivar.
COBISS.SI-ID: 7536505
Traditional olive cultivars often need minor phenotypic corrections, which can be assessed using mutation breeding. We investigated the effects of X-ray irradiation at 0, 10, 30 and 60 Gy delivered to in vitro grown shoots of the olive variety ‘Canino’. Morphological measurements showed that growth parameters did not decrease at a 10-Gy dose, that rooting ability was diminished at a 30-Gy dose and that shoot growth was inhibited at a 60-Gy dose. Measurements of acclimatized plants showed that nuclear DNA content decreased with increased irradiation doses. SSR profiling using 6 microsatellite loci revealed no polymorphism. AFLP analysis generated in total 630 scorable fragments within 13 primer combinations, of which 179 (28.4 %) were polymorphic. Although no major morphological changes were observed at a 10-Gy dose, a high number of absent/novel fragments were detected by AFLP analysis, indicating that mutation events can also be detected for doses at which growth parameters are not affected.
COBISS.SI-ID: 7652217
In this study, we evaluated twenty-three reference genes for RT-qPCR expression studies on hop under biotic stress conditions. The candidate genes were validated on susceptible and resistant hop cultivars sampled at three different time points after infection with Verticillium albo-atrum. The stability of expression and the number of genes required for accurate normalization were assessed by three different Excel-based approaches (geNorm v.3.5 software, NormFinder, and RefFinder). High consistency was found among them, identifying the same six best reference genes (YLS8, DRH1, TIP41, CAC, POAC and SAND) and five least stably expressed genes (CYCL, UBQ11, POACT, GAPDH and NADH). The candidate genes in different experimental subsets/conditions resulted in different rankings. A combination of the two best reference genes, YLS8 and DRH1, was used for normalization of RT-qPCR data of the gene of interest (PR-1) implicated in biotic stress of hop. We outlined the differences between normalized and non-normalized values and the importance of RT-qPCR data normalization. The high correlation obtained among data standardized with different sets of reference genes confirms the suitability of the reference genes selected for normalization. Lower correlations between normalized and non-normalized data may reflect different quantity and/or quality of RNA samples used in RT-qPCR analyses.
COBISS.SI-ID: 7653753