Effect of Gamma Irradiation on Penicillium expansum Isolated from "Golden Delicious" Apples

Postharvest diseases reduce postharvest quality and limit storage period of fruit. One of the alternative methods against the postharvest diseases is to use gamma irradiation. In this study, ten P. expansum isolates were collected from &quot;Golden Delicius? apples in cold storages of Kayseri. According to pathogenicity test, O2 isolate of P. expansum was found as the most virulent isolate and used in the experiment. In vitro, cultures were irradiated with 60Co gamma sources (with dose rate of 0.668 kGy h-1and specific radioactivity of 1026.2 Curie), incubated at 3-4&ordm;C and 23&plusmn;1&ordm;C. At 27th day while mean the colony diameter of untreated cultures was 25.87 mm, the cultures treated with 3.0 kGy had a diameter of 9.12 mm in 3-4&ordm;C. Similarly, at 9th days 3.0 kGy treated cultures and untreated cultures had a mean colony diameter of 37.50 mm and 54.87 mm, respectively, at 23&plusmn;1&ordm;C. The optimum dose was 3.0 kGy for both incubation temperatures. Differences between doses were also significant at p&lt; 0.05 level. The area under the disease progress curve (AUDPC) was calculated for each individual treatment and observation day in vitro. Confirming statistical analysis, the lowest AUDPC value was found at 3.0 kGy treatment.</p

First report on Grapevine leafroll associated virus 1 infecting pomegranate trees (Punica granatum L.) in Turkey

Pomegranate (Punica granatum L.) has been cultivated since ancient times through the Mediterranean region, Asia, Africa and some parts of Europe. The main production countries being mainly Mediterranean and Asian countries such as India, Iran, China and Turkey. Turkey is one of the leading producer and exporter for this fruit and total pomegranate production reached 315.000 tons in 2012 that corresponds to one of the largest pomegranate economies in the world. Hatay, located in Eastern Mediterranean region, is one of the most important centers of diversity in pomegranate in Turkey. Recently symptoms resembling virus infection in&nbsp; local pomegranate cultivars were observed in late summer-autumn periods in Hatay province. Pomegranate leaves showing yellowing, chlorotic spots, vein clearing and oak-leaf symptoms were sampled to verify possible virus association with these symptoms. DAS-ELISA and RT-PCR analysis were used for the detection of suspecious viruses infecting fruit trees, grapevines and potatoes such as Plum pox virus, Prunus necrotic spot virus, Apple mosaic virus, Apple chlorotic ring spot virus, Apple stem grooving virus, Arabis mosaic virus, Grapevine leafroll associated virus 1, 2, 3, 4-9, 6, 7, Grapevine virus A, Cucumber mosaic virus, Pepino mosaic virus, Potato virus X, Potato virus Y (PVYN), Potato virus M and Potato leafroll virus. Plant sap extraction for ELISA and Nucleic acid extraction for PCR analysis were performed from leaf and shoots of three strong symptomatic and twenty suspecious plants. Due to high content of metabolic compounds such as polyphenols and anthocyanins in pomegranate tissues, nucleic acid extractions did not result in high quality RNA in most of the conventional procedures used in this study, except modified CTAB based method. One set of primer F5&#39;-GTTACGGCCCTTTGTTTATTATGG-3&#39; and R5&#39;-CGACCCCTTTATTGTTTGAGTATG-3&#39; was used to amplify coat protein gene (397 bp) of GLRaV-1. According to ELISA and RT-PCR analysis only three symptomatic plant samples yielded positive results for Grapevine leafroll associated virus-1 (GLRaV-1) among tested viruses whereas all other samples were negative for all tested viruses. Up to now, there are only a few reports on Cucumber mosaic virus and Hop stunt viroid in pomegranates. To the best of our knowledge, this is the first report to show GLRaV-1 in pomegranate trees.&nbsp;</p