Understanding the interactions between pathogen, crop and vector are necessary for the development of disease control practices of vector-borne pathogens. For instance, resistant plant genotypes can help constrain disease symptoms due to infections and limit pathogen spread by vectors. On the other hand, genotypes susceptible to infection may increase pathogen spread owing to their greater pathogen quantity, regardless of their symptom status. In this study, we evaluated under greenhouse conditions the relative levels of resistance (i.e. relatively lower pathogen quantity) versus tolerance (i.e. less symptom severity) of 10 commercial grapevine (Vitis vinifera) cultivars to Pierce’s disease etiological agent, the bacterium Xylella fastidiosa. Overall, no correlation was detected between pathogen quantity and disease severity, indicating the existence of among-cultivar variation in plant response to infection. Thompson Seedless and Barbera were the two most susceptible among 10 evaluated cultivars. Rubired showed the least severe disease symptoms and was categorized as one of the most resistant genotypes in this study. However, within each cultivar the degree of resistance/tolerance was not consistent across sampling dates. These cultivar and temporal differences in susceptibility to infection may have important consequences for disease epidemiology and the effectiveness of management protocols.

Some diseases manifest as one characteristic set of symptoms to the host, but can be caused by multiple pathogens. Control treatments based on plant symptoms can make it difficult to effectively manage such diseases, as the biology of the underlying pathogens can vary. Grapevine leafroll disease affects grapes worldwide, and is associated with several viral species in the family Closteroviridae. Whereas some of the viruses associated with this disease are transmitted by insect vectors, others are only graft-transmissible. In three regions of California, we surveyed vineyards containing diseased vines and screened symptomatic plants for all known viral species associated with grapevine leafroll disease. Relative incidence of each virus species differed among the three regions regions, particularly in relation to species with known vectors compared with those only known to be graft-transmitted. In one region, the pathogen population was dominated by species not known to have an insect vector. In contrast, populations in the other surveyed regions were dominated by virus species that are vector-transmissible. Our survey did not detect viruses associated with grapevine leafroll disease at some sites with characteristic disease symptoms. This could be explained either by undescribed genetic diversity among these viruses that prevented detection with available molecular tools at the time the survey was performed, or a misidentification of visual symptoms that may have had other underlying causes. Based on the differences in relative prevalence of each virus species among regions and among vineyards within regions, we expect that region and site-specific management strategies are needed for effective disease control.

Background Head and neck cancer and its treatment can cause impairment in survivors’ sexuality. Previous studies show a need for education and psychological support. Aim To examine patients’ priorities and preferences for discussing and receiving information about sexuality and to examine patient perceptions of existing self-report measures used in research. Methods This descriptive, cross-sectional, Web-based study recruited adults with a current or previous diagnosis of head and neck cancer. Participants answered questions about their priority and preference for receiving information about sexuality and reviewed 4 self-report measures commonly used in the research of this population. Results More than 80% (n = 61) of participants reported that it was important to receive information about sexual issues. Participants chose “at the time of diagnosis” as the most frequent answer for preferred time to receive this information. Half of the participants (n = 35) indicated that they prefer discussing sexual issues with a health-care provider. The most frequent answer for the method of receiving information was through discussions. Participants endorsed 4 themes not addressed by self-report surveys: (i) elicitation of important information, (ii) symptom burden issues, (iii) psychological issues, and (iv) physical barriers. Clinical Implications Providers, regardless of specialty, must attempt or facilitate discussions around these issues at various times within the treatment and recovery phases. Strengths & Limitations Although limited by sample representation and cross-sectional design, this study addresses an important patient-centered issue that is a critical aspect of quality of life. Conclusions Patients prefer to discuss sexual issues in person with their health-care providers at the time of diagnosis. Participants reacted positively to the self-report measures, but they felt that important issues faced by patients with head and neck cancer were not fully addressed.

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