The molecular characterization of HSVd isolates associated with dapple fruit and fruit rugosity in plum seedlings suggests a possible role of breeding in viroid dissemination

In a wide range of hosts, the infection caused by Hop stunt viroid (HSVd) appears to be latent, whereas in some others it is frequently pathogenic. In this work, the presence of HSVd has been found to be associated with symptoms of dapple fruit and fruit rugosity in plum seedlings obtained from cross breeding for quality. Symptomatic and symptomless plum seedling samples have been analyzed for the presence of the principal stone fruit viroids and viruses. HSVd was found in all symptomatic samples, whereas no other viruses or viroids were found in the analyzed samples with the exception of ACLSV, which was detected rarely. The RNAs of all HSVd isolates have been cloned and sequenced. The sequence analysis showed a high percentage of homology among the isolates, making it possible to hypothesize a potential unique origin of the infection. For this purpose, those plants used in breeding as pollen donors have been analyzed. The results showed that the same HSVd isolate was also present in the parental plants, both in the leaves and pollen, suggesting a possible role of breeding in the dissemination of the viroid.Keywords: Plum, seedlings, fruit rugosity, dapple fruit, HSVd, polle

Identification and characterization of Peach latent mosaic viroid and Hop stunt viroid in different peach cultivars showing dapple fruit, fruit yellow mosaic and cracked suture symptoms

From the early 1990s, a fruit peach syndrome characterized mainly by small discoloured spots (dapple fruit) and/or yellow areas on the skin (yellow mosaic), cracked suture and deformations was identified in most commercial orchards in the Emilia Romagna region (Northern Italy). In the past, Peach latent mosaic viroid (PLMVd) and Hop stunt viroid (HSVd) have been detected in trees with symptomatic fruits. In order to ascertain the presence and spread of these two viroids, symptomatic fruit samples were collected from five different cultivars: ‘Royal Glory’, ‘Crimson Lady’, ‘Grenat’, ‘Diamond Princess’ and ‘Laura’. Dapple fruit symptoms affected all cultivars, ‘Grenat’ samples also showed evident yellow mosaic and fruit deformation, and ‘Royal Glory’ severe cracked sutures. The results showed a large diffusion of the two viroids, mainly in mixed infections. Anvaluation of the role the viroids could play in symptom expression has been complicated by the high number of samples infected by both viroids (60%). Nonetheless, PLMVd was confirmed to be strictly associated with the yellow mosaic, cracked suture and fruit deformation symptoms. The aetiological origin of the dapple fruit disease, however, seems to be more complicated, since in the ‘Diamond Princess’, only PLMVd has been found to be associated with the symptoms, whereas in all other cultivars, the presence of HSVd could have influenced the symptom expression. Moreover, the molecular characterization of some PLMVd isolates does not show any correlation between nucleotide sequence and symptoms although new PLMVd variants were identified. Keywords: peach fruit symptoms, PLMVd, HSVd, mixed infectio

Improving Dermal Delivery of Rose Bengal by Deformable Lipid Nanovesicles for Topical Treatment of Melanoma

Cutaneous melanoma is one of the most aggressive and metastatic forms of skin cancer. However, current therapeutic options present several limitations, and the annual death rate due to melanoma increases every year. Dermal delivery of nanomedicines can effectively eradicate primary melanoma lesions, avoid the metastatic process, and improve survival. Rose Bengal (RB) is a sono-photosensitizer drug with intrinsic cytotoxicity toward melanoma without external stimuli but the biopharmaceutical profile limits its clinical use. Here, we propose deformable lipid nanovesicles, also known as transfersomes (TF), for the targeted dermal delivery of RB to melanoma lesions to eradicate them in the absence of external stimuli. Considering RB's poor ability to cross the stratum corneum and its photosensitizer nature, transfersomal carriers were selected simultaneously to enhance RB penetration to the deepest skin layers and protect RB from undesired photodegradation. RB-loaded TF dispersion (RB-TF), prepared by a modified reverse-phase evaporation method, were nanosized with a ζ-potential value below -30 mV. The spectrophotometric and fluorimetric analysis revealed that RB efficiently interacted with the lipid phase. The morphological investigations (transmission electron microscopy and small-angle X-ray scattering) proved that RB intercalated within the phospholipid bilayer of TF originating unilamellar and deformable vesicles, in contrast to the rigid multilamellar unloaded ones. Such outcomes agree with the results of the in vitro permeation study, where the lack of a burst RB permeation peak for RB-TF, observed instead for the free drug, suggests that a significant amount of RB interacted with lipid nanovesicles. Also, RB-TF proved to protect RB from undesired photodegradation over 24 h of direct light exposure. The ex vivo epidermis permeation study proved that RB-TF significantly increased RB's amount permeating the epidermis compared to the free drug (78.31 vs 38.31%). Finally, the antiproliferative assays on melanoma cells suggested that RB-TF effectively reduced cell growth compared to free RB at the concentrations tested (25 and 50 μM). RB-TF could potentially increase selectivity toward cancer cells. Considering the outcomes of the characterization and cytotoxicity studies performed on RB-TF, we conclude that RB-TF represents a valid potential alternative tool to fight against primary melanoma lesions via dermal delivery in the absence of light

Il giallume europeo delle drupacee.

In Italia ed in Europa, particolarmente nei paesi che si affacciano sul Mediterraneo, sono presenti su varie drupacee coltivate e spontanee diverse sindromi causate dal fitoplasma del giallume europeo delle drupacee; alcune di queste come l\u2019accartocciamento fogliare clorotico dell\u2019albicocco e la leptonecrosi del susino sono note da tempo ed ampiamente diffuse, mentre su altre specie, come il pesco, la gravit\ue0 appare minore, anche negli ultimi anni si \ue8 assistito ad un preoccupante aumento della malattia negli impianti peschicoli del Italia Settentrionale. Altre specie come il susino europeo sono invece tolleranti, anche talvolta alcune cultivar possono evidenziare sintomi lievi. Il patogeno viene trasmesso dalla psilla delle drupacee, Cacopsylla pruni (Scopoli). Si prendono in considerazione le principali sindromi causate dal fitoplasma del giallume europeo delle drupacee nel nostro Paese, indicando anche il comportamento di variet\ue0 e portinnesti nei confronti della malattia. Viene inoltre dedicata una particolare attenzione alle modalit\ue0 di trasmissione, ai metodi diagnostici e alle possibili forme di contenimento della malattia: molto importante risulta la scelta del materiale vivaistico per la costituzione di impianti sani, mentre permangono ancora dubbi circa la capacit\ue0 di limitare la diffusione della malattia con la difesa insetticida in presenza di popolazioni ridotte del vettore

La moria del pero

Vengono trattate le principali caratteristiche sintomatologiche della moria del pero, che rappresenta oggi uno dei principali problemi sanitari in tutte le aree di coltivazione di questa pomacea. Viene inoltre dedicata particolare attenzione alla suscettibilit\ue0 all'infezione delle principali variet\ue0 e portinnesti, alle modalit\ue0 di trasmissione, alla diagnosi del fitoplasma agente della malattia ed alle modalit\ue0 di lotta