ORIGINAL ARTICLE
Overwintering form of Erysiphe necator, the causal agent of grapevine powdery mildew in southern Syria
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1
Second Faculty of Agriculture, Damascus University, Sweida, Syria
2
Department of Plant Protection, Faculty of Agriculture, Damascus University, 30621 Damascus, Syria
3
National Commission for Biotechnology, 301902, Damascus, Syria
Submission date: 2016-09-23
Acceptance date: 2017-05-17
Journal of Plant Protection Research 2017;57(2):129-135
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ABSTRACT
The main aims of this study were to determine the overwintering form and the primary inoculum of Erysiphe necator, the causal agent of grapevine powdery mildew in southern Syria. Eleven vineyards located at five different geographical sites were visited every week from March to November in 2014 and 2015. The results of field and histopathological studies showed that E. necator survived as mycelium in dormant grapevine buds during the winter season. The first flag shoots were observed shortly aftter bud break in spring. The number of flag shoots varied greatly according to vineyards, cultivars and years, being present on 27.4 to 61.9% of the grapevines in 2014, and on 5.2 to 40% of the grapevines in 2015. The percentage of flag shoots on the same grapevine also varied according to the year, cultivar and location. It was between 4.3 to 9.4% in 2014, and 2.1 to 3.6% in 2015. The disease was observed only on Balady and Black cultivars. Conidia were released from the second week of May to early September. The first conidia were trapped around mid-May, and the first secondary symptoms were observed on leaves from mid-May to early June according to the site. Chasmothecia were observed on leaves in 45.5% of the studied vineyards. The first observation
of chasmothecia on leaves was in July, and their numbers varied greatly between
vineyards and years. Chasmothecia were not detected on bark, nor were ascospores trapped at the beginning of the season. These results confirmed that the ascospores did not have any role in the initiation of spring infection. To the best of our knowledge, this is the first report of the overwintering form of E. necator in Syria.
CONFLICT OF INTEREST
The authors have declared that no conflict of interests exist.
REFERENCES (36)
1.
Austin C.N., Wilcox W.F. 2011. Effects of fruit-zone leaf removal, training systems, and irrigation on the development of grapevine powdery mildew. American Journal of Enology and Viticulture 62 (2): 193–198. DOI: 10.5344/ajev.2010.10084.
2.
Banihashemi Z., Parvin S. 1995. The occurrence of ascigenous stage of Uncinula necator var. necator in fars. Iranian Journal Plant Pathology 31: 1–4.
3.
Beyer G., Huber B., Kassemeyer H.H. 1998. Investigations on relationships of treatments before bloom against Uncinula necator, appearance of flag shoots and epidemics on leaves and grapes in 1993–1997. SARDI Research Report Series No. 22: 54.
4.
Bulit J., Lafon R. 1978. Powdery mildew of the vine. p. 525–548. In: “The Powdery Mildews” (D.M. Spencer, ed.). Academic Press, New York.
5.
Cortesi P., Bisiach M., Ricciolini M., Gadoury D.M. 1997. Cleistothecia of Uncinula necator – an additional source of inoculum in Italian vineyards. Plant Disease 81 (8): 922–926. DOI: 10.1094/PDIS.1997.81.8.922.
6.
Cortesi P., Gadoury D.M., Seem R.C., Pearson R.C. 1995. Distribution and retention of cleistothecia of Uncinula necator on the bark of grapevines. Plant Disease 79: 15–19.
7.
Emmett R.W., Wicks T.J., Magarey P.A., Madge D.G. 1990. Recent developments in grapevine powdery mildew management. Australian and New Zealand Wine Industry Journal 5 (3): 213–217.
8.
Fathi H., Karbalaei H. 2012. Study of biology and epidemiology of Uncinula necator caused powdery mildew disease. Technical Journal of Engineering and Applied Sciences 2 (3): 56–61.
9.
Gadoury D.M., Cadle-Davidson L., Wilcox W.F., Dry I.B., Seem R.C., Milgroom M.G. 2011. Grapevine powdery mildew (Erysiphe necator): A fascinating system for the study of the biology, ecology and epidemiology of an obligate biotroph. Molecular Plant Pathology 13 (1): 1–16. DOI: 10.1111/j.1364-3703.2011.00728.x.
10.
Gadoury D.M., Pearson R.C., Riegel D.G., Seem R.C., Becker E.M., Psheidt J.W. 1994. Reduction of powdery mildew and other diseases by over-the-trellis applications of lime sulfur to dormant grapevines. Plant Disease 78 (1): 83–87.
11.
Gadoury D.M., Seem R.C., Pearson R.C., Wilcox W.F. 2001. Effects of powdery mildew on vine growth, yield, and quality of concord grapes. Plant Disease 85 (2): 137–140. DOI: 1094/PDIS.2001.85.2.137.
12.
Gee L.M., Stummer B.E., Gadoury D.M., Biggins L.T., Scott E.S. 2000. Maturation of chasmothecia of Uncinula necator (powdery mildew) and release of ascospores in southern Australia. Australian Journal of Grape and Wine Research 6 (1): 13–20. DOI: 10.1111/j.1755-0238.2000.tb00157.x.
13.
Gemmrich A.R., Seidel M. 1996. Immunodetection of overwintering Oidium mycelium in bud scales of Vitis vinifera. Vitis 35 (1): 63–64.
14.
Grove G.G. 2004. Perennation of Uncinula necator in vineyards of Eastern Washington. Plant Disease 88 (3): 242–247. DOI: 10.1094/PDIS.2004.88.3.242.
15.
Grove G., Davis G., Duplaga B., Boal R. 1999. Powdery mildew of grape: Perennation of Uncinula necator in Eastern Washington. Phytopathology 89: S30.
16.
Gubler W.D., Fogle D.G., Chellemi D.O. 1988. Viability and pathogenicity of Uncinula necator ascospores in California. Phytopathology 78: 1572.
17.
Hajjeh H., Miazzi M., Faretra F. 2008. Overwintering of Erysiphe necator Schw. in Southern Italy. Journal of Plant Pathology 90 (2): 323–330.
18.
Halleen P., Holz G. 2000. Chasmothecia and flag shoots: sources of primary inoculum for grape powdery mildew in the Western Cape province, South Africa. South African Journal of Enology and Viticulture 21: 66–70.
19.
Halleen F., Holz G. 2001. An overview of the biology, epidemiology and control of Uncinula necator (powdery mildew) on grapevine, with reference to South Africa. South African Journal of Enology and Viticulture 22: 111–121.
20.
Hill G.K., Baumberger I., Spies S. 1995. Studies on the occurrence of the chasmothecia of Uncinula necator (Schw.) Burr. in two vine growing areas of Germany. Viticulture and Enology Sciences 50: 3–8.
21.
Holb I.J., Füzi I. 2016. Monitoring of ascospore density of Erysiphe necator in the air in relation to weather factors and powdery mildew development. European Journal of Plant Pathology 144 (4): 751–762. DOI: 10.1007/s10658-015-0823-4.
22.
Pathology 144 (4): 751–762. DOI: 10.1007/s10658-015-0823-4.
23.
Jailloux F., Willocquet L., Chapuis L., Froidefond G. 1999. Effect of weather factors on the release of ascospores of Uncinula necator, the cause of grape powdery mildew, in the Bordeaux region. Canadian Journal of Botany 77 (7): 1044–1051. DOI: 10.1139/b99-118.
24.
Khiavi H.K., Shikhlinski H., Ahari A.B., Heydari A. 2009. Evaluation of different grape varieties for resistance to powdery mildew caused by Uncinula necator. Journal of Plant Protection Research 49 (4): 434–439. DOI: 10.5897/AJAR12.1056.
25.
Magarey R.D., Wachtel M.F., Masters J., Wilkins B.J. 1993. Chasmothecia as primary inoculum sources of grapevine powdery mildew (Uncinula necator) in Australia. Australian and New Zealand Wine Industry Journal 8: 239–241.
26.
Magarey P.A., Magarey R.D., Emmett R.W. 2000. Principles for managing the foliage diseases of grapevine with low input of pesticides. IFOAM 2000 – the world grows organic. p. 140–148. In: Proceedings of the 6th International Congress on Organic Viticulture, Convention Center, Basel, Switzerland, 25–26 August 2000.
27.
Miladinovic Z., Vuksa P., Miletic N. 2007. Uncinula necator (Schw.) Burr: source of inoculum in Podgorica vineyards. Pesticidi i Fitomedicina 22: 131–135.
28.
Moyer M.M., Gadoury D.M., Wilcox W.F., Seem R.C. 2008. Seasonal release of ascospores by Erysiphe necator. Phytopathology 98: S109.
29.
Pearson R.C. 1990. Current research on grape fungal diseases and their control in New York. Australian and New Zealand Wine Industry Journal 5: 206–209.
30.
Pearson R.C., Gärtel W. 1985. Occurrence of hyphae of Uncinula necator in buds of grapevine. Plant Disease 69: 149–151.
31.
Pearson R.C., Gadoury D.M. 1987. Chasmothecia, the source of primary inoculum for grape powdery mildew in New York. Phytopathology 77: 1509–1514.
32.
Pearson R.C., Gadoury D.M. 1992. Grape powdery mildew. p. 129–146. In: “Plant Diseases of International Importance” Vol. III. Diseases of Fruit Crops (J. Kumar, H.S. Chaube, U.S. Singh, A.N. Mukhopadhyay, eds.). Englewood Cliff s, NJ, Prentice Hall.
33.
Péros G.P., Troulet C., Guerriero M., Romiti C.M., Notteghem J.L. 2005. Genetic variation and population structure of the grape powdery mildew fungus, Erysiphe necator, in southern France. European Journal of Plant Pathology 113 (4): 407–416. DOI: 10.1007/s10658-005-4563-8.
34.
Sall M.A., Wrysinski J. 1982. Perennation of powdery mildew in buds of grapevines. Plant Disease 66 (8): 678–679.
35.
Steinkellner S. 1998. Overwintering of Uncinula necator in Austrian vineyards. Vitis 37: 193–194.
36.
Taksonyi P., Tarczal E., Maráczi K., Holb I., Kocsis L. 2010. Powdery mildew infection dependent on weather factors in vineyards near Keszthely in 2008. International Journal of Horticultural Science 16 (2): 55–59.