Suchergebnisse

Pathogen detection in the Italian outbreak area of X. fastidiosa is carried out using samples from symptomatic olive twigs and leaves. Conversely detection from asymptomatic trees is difficult due to the uneven pathogen distribution in olive cultivars. In this study the incidence and canopy distribution of the infection is under assessment in 4 olive cultivars (EU H2020 project 'Xf-Actors') grown in a field (about 1.5 Ha) in the infected area of Apulia. All trees were tested in March for the presence of X. fastidiosa using real time LAMP (Loop Mediated Isothermal Amplification). The highest infection rate was detected in 'Cellina di Nardò' (74%) and 'Cima di Melfi' (76%), whereas the lowest was recorded in 'Leccino' (61%) and 'Frantoio' (63%). Based on these results, 5 trees were selected from 'Cellina di Nardò' (highly susceptible) and 'Leccino (less susceptible). About 4 twigs were randomly collected from 3 levels of the asymptomatic sector of the canopy and each twig was divided in 3 portions. About 180 samples/cultivar are collected 3 times from March to July and tested by DTBIA and real time LAMP. After the first 2 samplings a preliminary difference was noticed on the infection distribution: the whole canopy in the case of 'Cellina di Nardò' and the lower part of the canopy in the case of 'Leccino'. However, final results will be achieved after the 3rd sampling in July and data analysis by Univariate and Multivariate ANOVA test. ; Acknowledgment This work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement N. 727987 "Xylella fastidiosa Active Containment Through a multidisciplinary-Oriented Research Strategy XF-ACTORS".

Aims. The complexity of star formation at the physical scale of molecular clouds is not yet fully understood. We investigate the mechanisms regulating the formation of stars in di erent environments within nearby star-forming galaxies from the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) sample. Methods. Integral field spectroscopic data and radio-interferometric observations of 18 galaxies were combined to explore the existence of the resolved star formation main sequence ( stellar versus SFR), resolved Kennicutt–Schmidt relation ( mol: gas versus SFR), and resolved molecular gas main sequence ( stellar versus mol: gas), and we derived their slope and scatter at spatial resolutions from 100 pc to 1 kpc (under various assumptions). Results. All three relations were recovered at the highest spatial resolution (100 pc). Furthermore, significant variations in these scaling relations were observed across di erent galactic environments. The exclusion of non-detections has a systematic impact on the inferred slope as a function of the spatial scale. Finally, the scatter of the mol: gas+stellar versus SFR correlation is smaller than that of the resolved star formation main sequence, but higher than that found for the resolved Kennicutt–Schmidt relation. Conclusions. The resolved molecular gas main sequence has the tightest relation at a spatial scale of 100 pc (scatter of 0:34 dex), followed by the resolved Kennicutt–Schmidt relation (0:41 dex) and then the resolved star formation main sequence (0:51 dex). This is consistent with expectations from the timescales involved in the evolutionary cycle of molecular clouds. Surprisingly, the resolved Kennicutt–Schmidt relation shows the least variation across galaxies and environments, suggesting a tight link between molecular gas and subsequent star formation. The scatter of the three relations decreases at lower spatial resolutions, with the resolved Kennicutt–Schmidt relation being the tightest (0:27 dex) at a spatial scale of 1 kpc. Variation in the slope of the resolved star formation main sequence among galaxies is partially due to di erent detection fractions of SFR with respect to stellar. ; European Research Council (ERC) 694343 726384/Empire National Science Foundation (NSF) 1615105 1615109 1653300 ANID project Basal AFB-170002 German Research Foundation (DFG) KR4801/1-1 German Research Foundation (DFG) European Commission KR4801/2-1 SFB 881 138713538 European Research Council (ERC) 714907 German Research Foundation (DFG) KR4598/2-1 Instituto de Salud Carlos III Spanish Government PID2019-106027GA-C44 Spanish funding grant (MINECO/FEDER) AYA2016-79006-P Spanish funding grant (MCIU/AEI/FEDER) PGC2018-094671-B-I00 Spanish funding grant (MICINN) PID2019-108765GB-I00 European Research Council (ERC) European Commission 855130 Heidelberg cluster of excellence - German Excellence Strategy EXC 2181 - 390900948 European Organisation for Astronomical Research in the Southern Hemisphere under ESO 094.C-0623 098.C-0484 1100.B-0651 ; Versión publicada - versión final del editor