• Non ci sono risultati.

Relations between the climate and the incidence of the nut rot of chestnuts caused by Gnomoniopsis castanea

N/A
N/A
Protected

Academic year: 2021

Condividi "Relations between the climate and the incidence of the nut rot of chestnuts caused by Gnomoniopsis castanea"

Copied!
1
0
0

Testo completo

(1)

RELATIONS BETWEEN THE CLIMATE AND THE INCIDENCE OF THE NUT ROT OF CHESTNUTS CAUSED BY

GNOMONIOPSIS CASTANEA. L. Giordano, G. Lione, F. Sillo, P. Gonthier. Department of Agricultural, Forest and Food Sciences, University of Torino, Grugliasco, Italy. E-mail: paolo.gonthier@unito.it Gnomoniopsis castanea is the causal agent of an emerging nut rot on chestnut trees. A Partial Least Squares Regression (PLSR) analysis was performed to model the incidence of this fungal pathogen based on climate. The analysis involved four steps: I) assessment of the disease incidence, II) pre-selection of predictors, III) models fitting, IV) external validation.

I) In 2011 the incidence of G. castanea was assessed as percentage of infected nuts in 12 sites located in the north-west of Italy. Both

isolations and molecular analyses revealed that disease incidence ranged from 20% to 93%.

II) Geostatistical analyses showed that, despite the geographical clustering of sites (P < 0.05), the incidence of G. castanea was not spatially autocorrelated (P > 0.05). This finding suggests that site-dependent factors may influence the disease. A Principal Coordinates Analysis (PCoA) and a Hierarchical Cluster Analysis (HCA) on maximum, mean and minimum temperatures and on rainfalls showed that warmer temperatures were associated to a significant increase of disease incidence (+10.4%; P < 0.05). III) The temperatures of the months before nut harvesting were selected as predictors in the PLSR models. Bootstrap analyses and cross-validation were performed for models selection.

IV) External validation carried out on data collected from additional sites showed the good predictive abilities of the models

(

ρ

> 0.70; P < 0.05).

All the above findings indicate that the climate and the incidence of G. castanea are related, and that PLSR equation provide a useful statistical tool to forecast the incidence of the disease at site level.

Riferimenti

Documenti correlati

Objective: An observational case–control study was designed to analyse the discriminative value of ultrasound (US)-detected joint effusion compared with physical examination in

The di↵erent chemical shift dispersion of the structured and intrinsically disordered proteins is demonstrated by 2D 1 H- 15 N correlation spectra acquired on two proteins of

They found that after the delivery of 3 or 10 minutes of cathodal stimulation (1 mA, 40 cm 2 electrode) over the primary visual cortex, an increase in the P100 ampli- tude had

Il Master di I livello a distanza GESCOM “Gestione e sviluppo della conoscenza nell’area delle risorse umane” - promosso dal Dipartimento di studi dei processi

Discussion: The following vaccination strategies have been retrieved and analysed: the cocooning strategy, the immunization of pregnant women and newborns, vaccination programs

In [15] several periodic orbits of the Newtonian N -body problem have been found as minimizers of the Lagrangian action in suitable sets of T -periodic loops, for a given T &gt;

In occasione del quinto anniversario della riapertura di Palazzo Grassi, tra il 2 giugno 2011 e il 21 febbraio 2012, la fondazione affida a Caroline Bourgeois

Conversely, the target of the virus may not be the neurons but other non- neuronal cells that express ACE2 receptors such as the olfactory epithelium