First Report of Downy Mildew Caused by Peronospora belbahrii on Sweet Basil (Ocimum basilicum) in Cyprus.

Sweet basil (Ocimum basilicum L.) is an economically important annual aromatic plant, grown mostly for culinary use for both fresh and dry consumption and as a source of essential oil. In Cyprus, approximately 4 ha are grown annually, either in greenhouses as a year-round crop or in open fields from April to November, and the majority of the production is exported to the European market. During May 2012, a sweet basil cv. Genovese Gigante greenhouse operation in the area of Limassol was severely affected by a foliar disease, causing almost 100% crop losses. Within a few days, a similar, heavy disease incidence was also reported from a nearby greenhouse facility on the Genovese-type cultivars Superbo, Aroma 2, and Bonazza, as well as on Thai basil (O. basilicum var. thyrsiflorum). Successively, destructive hits of similar symptomatology have been reported from other areas and since then the disease appears to have been well-established in the country, causing major economic damages. It is also noteworthy to mention that in greenhouse infections the disease remains active even during winter, considering the mild environmental conditions and the monoculture fashion followed. Symptoms appeared on the leaves initially as interveinal, zonal, chlorotic lesions, followed by the appearance of a fuzzy, purplish sporulation on the abaxial side. Progressively, infected leaves curled and sporadic necrotic spots were evident and finally abscised. Light microscopic examination of infected samples revealed the presence of straight, hyaline sporangiophores (n = 15) typical of downy mildew, 210 to 590 µm long (mean = 350.7 µm; SD ± 117.5 µm) × 12 to 15 µm wide (mean = 13.1 µm; SD ± 1.4 µm). Sporangiophores were monopodially branched three to five times, terminating with curved branchlets bearing single sporangia at their tips. The sporangia (n = 25) were purplish-grey, ovoid to subglobose, and measured 32 to 22 µm in length (mean = 27.2 µm; SD ± 2.8 µm) and 30 to 10 µm in breadth (mean = 21.7 µm; SD ± 4.8 µm). Based on these morphological characteristics, the causal agent was identified as Peronospora belbahrii Thines (1,4). Furthermore, genomic DNA was extracted from infected plant tissue from eight different samples according to Dellaporta et al. (2). The complete ITS rDNA region was amplified and sequenced using primers ITS5 and ITS4 (3). Two of the consensus sequences were deposited in GenBank (Accession Nos. KF419289 and KF419290) and a BLAST analysis in the NCBI database revealed 99% similarity to all of the P. belbahrii sequences and other Peronospora sp. previously reported on sweet basil (Accession Nos. AY831719, DQ479408, FJ394336, and FJ436024). In a pathogenicity trial, five 40-day-old potted sweet basil plants were spray-inoculated with a sporangial suspension (1 × 105 sporangia/ml) until runoff, bagged for 24 h, and placed in a growth chamber at 18°C. Subsequently, the plastic bags were removed and the plants were kept at 22°C with a 16-h photoperiod and 80% relative humidity. Additionally, five plants were water-sprayed and served as controls. Typical downy mildew symptoms appeared 6 to 8 days after inoculation, while the uninoculated plants remained disease-free. To our knowledge, this is first report of downy mildew on sweet basil in Cyprus. References: (1) L. Belbahri et al. Mycol. Res. 109:1276, 2005. (2) S. L. Dellaporta et al. Plant Mol. Biol. Rep., 1:19, 1983. (3) G. Nagy and A. Horvat, Plant Dis. 93:1999, 2009. (4) M. Thines et al. Mycol. Res. 113:532, 2009.

Soil treatment with hot air (Cultivit) as alternative to methyl bromide.

A new development in physical soil treatment is the application of hot air. Hot air treatment is based on blowing extremely hot air into rotavating humid soil. The method has been developed and applied commercially in Israel for the last few years. An increased growth response (IGR) was observed in several crops like potato, cauliflower, kohlrabi and the flower Esclepia, when the soil was treated with hot air prior to planting. Scientific trials were performed in Israel and Cyprus to quantify IGR and to evaluate the efficacy against plant-parasitic nematodes. Squash was grown in tunnels on root-knot nematodes (Meloidogyne javanica and M. incognita) infested fields in sandy (Israel) and clay loam (Cyprus) soils. In Israel hot air treatment was compared with metam sodium and methyl bromide and a cold air treated control. In Cyprus hot air treatment was compared with untreated control. Hot air treatment increased squash yield in Israel with 90 % and in Cyprus with 150%. Root assessments showed that after hot air treatment the root-knot nematodes were still able to infest plants and cause galling damage. Nematode counts were not reduced by hot air treatment. It may be concluded that the general concept of soil disinfestation is not applicable to hot air treatment. Any positive effect in yield could not be explained by reduction in nematode populations in soil. Possible chemical and biological changes in the hot air treated soils need to be identified. Further research will determine the possibilities and limitations of this method in other crops and under various climatic conditions.

A scrapie epidemic in Cyprus.

Scrapie is endemic in the sheep flocks of many countries, but good epidemiological information on this disease is scarce. Data on the initial stages of an epidemic are even more rare. We describe the ongoing epidemic of scrapie in Cyprus that has been tracked since it began in the mid-1980s. The early stages of the spread of scrapie from farm to farm, between 1985 and 2000, is analysed with a simple mathematical model. The flock-to-flock basic reproductive number (R0) for the spread of scrapie was estimated at between 1.4 and 1.8. The impact of interventions on the control of the epidemic are discussed from an epidemiological and economic point of view. Early identification of scrapie cases on farms can have a large impact on the number of farms affected. The long period before detection of disease in a flock means that policies based on whole-flock slaughter can be inefficient in preventing spread. Under a range of scenarios, a concentration of resources on early detection and quarantine may be more effective in terms of both the costs and control of the epidemic.

[Results of vaginal cytology studies and examination of the arborization phenomenon of the vaginal mucus for the determination of estrus cycle activity in sheep]. / Ergebnisse vaginalzytologischer Untersuchungen und Prüfung des Arborisationsphänomens des Vaginalschleimes zur Erfassung der Ostruszyklusaktivitt beim Schaf

Vaginal smears were taken by means of a metal spatula from the dorsal part of the vaginal vestibule of sexually mature sheep with intach genitals for the purpose of following up changes in the vaginal cell structure. The smears were taken daily over the whole testing period of 35 days. The cells were defferentiated by means of the dyeing method according to Papanicolaou as well as by using Shorr's staining which had been modified according to Pundel. Differentiation was made between occurrences ob basal, parabasal, intermediary, and superficial cells, with the view to figuring out the cycle phases. That vaginal smear method, when used in two or three folloow-up examinations on the basis of random checks, has proved to enable determination of cyclic activity of a complete herd. This is of great importance to heart synchronization or heart induction, since all results so far have shown that all success depended strongly on the given degree of cyclic activity of the sheep concerned.