Fifty-seven wild olive accessions collected from the Mediterranean basin were screened under greenhouse conditions for their resistance to verticillium wilt. Plants were root-dip inoculated. One defoliating and one non-defoliating isolate of Verticillium dahliae, both obtained from diseased plants in southern Italy, were used. Plants of the highly susceptible cv. Cima di Mola, frequently used as a rootstock in Apulia, were also included in this test. Disease reactions were evaluated on the basis of external symptoms, vascular browning and by calculating areas under disease progress curves (audpc). On the basis of Audpc values and external symptom severity, accessions were grouped into four phenotypic groups: highly resistant, moderately resistant, susceptible and highly susceptible. Three accessions showed high resistance to both V. dahliae pathotypes. Forty resistant plants were selected from accessions that had shown the highest levels of resistance. Clones were obtained from each of these plants by in vitro micropropagation for further testing. Ten clones showed the resistance characteristics of their original mother plants, while others suffered greater levels of disease severity than their mother plants. Several new olive rootstocks were identified that were highly resistant to verticillium wilt and could be included in breeding programmes for resistance of olive to V. dahliae
Among 146 accessions of Lycopersicon pimpinellifolium, 132 of L. esculentum var. cerasiforme and 53 of L. peruvianum screened for resistance to powdery mildew, caused by Oidium lycopersici, a wide variation in reactions was found. Two plants of L. esculentum var. cerasiforme accession LA-1230 were resistant. One resistant symptomless plant of accession LA-1230, designated LC-95, produced homozygous resistant progenies. LC-95 was crossed with cv. Marmande (susceptible parent) and F 1 , F 2 and backcrosses to the resistant and the susceptible parents were derived. These genotypes were grown in glasshouses at 23ЊC and 95-100% RH and inoculated with O. lycopersici. The F 1 plants were susceptible. F 2 and backcross segregations fitted the hypothesis of a single recessive gene which is here designated ol-2.
Verticillium wilt is becoming an increasing concern in artichoke production because the rapid spread of the disease to new growing areas has led to declining production. Scientists from Italy, Spain, and the United States combine to bring us up to date on diagnosis of the disease, its epidemiology and life cycle, as well as management strategies, current and forthcoming.
In the present investigation fresh and dried tomato samples from markets and packinghouses located in Apulia (southern Italy) were analysed for Alternaria toxins. All samples proved to be contaminated by tenuazonic acid (TeA). Dried tomatoes were contaminated in the range 425-81,592 µg/kg, whereas fresh tomatoes in the range 10.7-4,560 µg/kg. The second most abundant toxin was alternariol monomethyl ether (AME), followed by tentoxin (TEN) and alternariol (AOH). Overall dried tomatoes were more contaminated than the fresh ones, although this seemed not directly due to the presence of sodium chloride. Five representative Alternaria isolates within those collected from samples proved to be one Alternaria arborescens (A215) and four Alternaria alternata. Within the latter species one strain belonged to morphotype tenuissima (A216), and three to alternata (A214, A217 and A218).They confirmed to produce TeA, AOH, and AME in vitro. This study demonstrates the possible risk for consumers' health related to the consumption of contaminated fresh and dried tomatoes, and thus the need perform suitable control strategies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.