Nazli Dide Kutluk Yilmaz

Effects of Azadirachtin on Beet Soilborne Pomovirus and Soil Biological Properties on Sugar Beet

Beet soilborne pomovirus (BSBV) is an important soilborne virus disease in growing areas of sugar beet. BSBV was transmitted by Polymyxa betae Keskin. Effects of azadirachtin on BSBV and soil biological properties were studied under a greenhouse. The presence of BSBV was tested in soil samples using bait plant test and triple antibody sandwich-enzyme-linked immunosorbent assay (TAS-ELISA). The concentration of BSBV in sugar beet roots was significantly reduced by the application of azadirachtin to the soils. TAS-ELISA absorption values in 1.52, 3.04, and 7.60 ppm were lower than that 0.38 and 0.76 ppm of azadirachtin. Furthermore, in this study, it was determined the 0.38, 0.76, and 1.52 ppm doses of azadirachtin in soils had high amounts of soil biological properties (Cmic, BSR, DHA), while the 3.04 and 7.60 ppm doses had no statistical significance compared to the control treatments.

Evaluation of suppression of rhizomania disease by earthworm (Lumbricus terrestris L.) and its effects on soil microbial activity in different sugar beet cultivars

The ability of earthworm Lumbricus terrestris L. to suppress the multiplication of Beet necrotic yellow vein virus (BNYVV) transmitted by Polymyxa betae and its effects on soil microbial activity were investigated under controlled conditions. BNYVV-infested and a combination of earthworm with BNYVV-infested soil were compared to non-infested soils for their effects on plant and root weights and virus content of two different sugar beet cultivars by using partially resistant (cv. Leila) and susceptible (cv. Arosa) cultivars to the rhizomania disease. Soil testing with sugar beet baiting plants followed by enzyme-linked immunosorbent assay (ELISA) was used to diagnose virus. The results of the statistical analyses showed that total fresh plant and root weights were negatively correlated with BNYVV infection. Addition of L. terrestris significantly enhanced plant and root weights. The earthworm-added soils had higher microbial activity such as basal soil respiration and dehydrogenase activity. The presence of earthworms in the soil did not statistically suppress BNYVV infection (p < 0.05). Sugar beet production may be enhanced by using resistant cultivars with adding L. terrestris into soil where rhizomania is present.

Investigation of soilborne mosaic virus diseases transmitted by Polymyxa graminis in cereal production areas of the Anatolian part of Turkey

Polymyxa graminis is the vector of several important viruses, including Soilborne cereal mosaic virus, Wheat spindle streak mosaic virus, Barley yellow mosaic virus and Barley mild mosaic virus, of winter cereals worldwide. Surveys were carried out to detect these viruses and their vector P. graminis in 300 soil samples from the main wheat and barley production areas of the Anatolian part of Turkey collected in May 2002, June 2004 and May 2005. For these surveys, various susceptible wheat and barley cultivars were pot grown in the collected soil samples in a greenhouse and then analysed using ELISA and RT-PCR to detect the presence of different virus species. In addition, a combination of light microscopy following roots staining with acid fuchsin and PCR was used for detection of P. graminis. All soil samples analysed were found to be free of these soilborne viruses and their vector.

Distribution of resistance-breaking isolates of beet necrotic yellow vein virus differing in virulence in sugar beet fields in Turkey

ABSTRACT Rhizomania, caused by Beet necrotic yellow vein virus (BNYVV), is one of the most devastating diseases on sugar beet throughout the world. A total of 235 BNYVV-infested soil samples taken from 29 provinces during the growing seasons of 2004–2005 and 2010–2011 were investigated for resistance-breaking properties of BNYVV isolates. BNYVV resistant (Rz1, Rz1 + R2, Rz1 + C48 + minor genes) and susceptible (rz1) sugar beet cultivars were grown in the BNYVV-infested soils by the bait plant technique, and virus infection was evaluated based on disease symptom and DAS-ELISA. Of the soil samples tested, 57.4% produced infection in the roots of sugar beet cultivar (cv.) containing the Rz1 gene, 51.9% in cv. carrying the Rz1 + Rz2 and 18.9% in cv. carrying the Rz1 + C48 + minor genes. Also, the presence of Beet soil-borne virus (BSBV) was evaluated by TAS-ELISA. Additionally, the presence of BNYVV RNA-5 component was investigated by RT–PCR using the primers specific for p26 coding region. Our results revealed that BNYVV isolates compromising resistance genes are highly common and widespread in sugar beet production areas in Turkey, and it seems unlikely that BSBV and/or RNA-5 were directly involved in RB-event.

Samsun ili ıspanak üretim alanlarında enfeksiyon oluşturan virüslerin belirlenmesi

Samsun ilinde ispanakta ( Spinacia oleracea L.) enfeksiyon olusturan virusleri ve bunlarin yayilislarini belirlemek amaciyla, Kasim 2014 - Ocak 2015 tarihleri arasinda Bafra ve Carsamba ilcelerine bagli koylerden yapraklarinda bukulme, kivrilma, klorotik lezyon, mozayik ve cucelesme belirtisi gosteren 100 adet bitki ornegi toplanmistir. Bu surveyler sonucunda, Enzyme Linked Immunosorbent Assay (ELISA) yontemi ile orneklerin %8’inin Cucumber mosaic virus (CMV) ve %3’unun Turnip mosaic virus (TuMV) ile bulasik oldugu belirlenmistir. Bu sonuc, Samsun ilinde ispanakta CMV ve TuMV enfeksiyonunun ilk kayiti niteligindedir. Bolgeden toplanan orneklerin hicbirinde Tomato spotted wilt virus (TSWV) ve Tobacco mosaic virus (TMV) enfeksiyonuna rastlanmamistir.

Rhizomania Hastalığının Şeker Pancarı Çeşitlerinde Bazı Agronomik Özelliklere Etkisi

In the present study, the reactions of certain sugar beet varieties were determined against Rhizomania disease in the location of Çamağzı-Ötegeçe (Tokat) that was known to be infested with the disease in 1995. According to the results obtained, it was found out that the virus which is the causal agent of disease affected negatively the agronomic features including root number, weight of top root and leaf and sugar content in sugar beet. The highest top root weight was in Gabriela, Rizor and Gina while the highest leaf weight was in Kowapura, Kawemaja and Fiona besides former varieties. In addition, it was observed that root number was the highest in Roxane and sugar content was higher than others in Gabriela, Gina and Rizor were observed.