Epidemiological Study of Blackleg Disease of Oilseed Rape (Brassica napus L.) in Relation to Climatic Indices in Golestan Province

Document Type : Plant Pathology

Authors

1 Department of Plant Protection, Faculty of Plant Production, Gorgan University of Agricultural Sciences and Natural Resources, Golestan, Iran

2 Plant Protection Research Department, Golestan Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Gorgan, Iran

3 Horticulture Science Department, Faculty of Plant Production, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran

4 Biological and Environmental Sciences Department, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom

Abstract

Blackleg disease of oilseed rape (Brassica napus L.), caused by the fungus Leptosphaeria maculans, is one of the major factors limiting canola production worldwide. This study was conducted to investigate the epidemiology of the disease and its relationship with climatic conditions in Golestan Province, Iran. The results showed that the disease occurred in all regions during both cropping seasons, but its severity and spread patterns are varied significantly among regions and years. During the leaf spot phase, the highest incidence and severity were recorded in the first year in Bandar-e-Gaz and in Gorgan in the second year. In the first year diseases incidence and deases severity were significantly associated with minimum temperature and relative humidity, whereas in the second year, maximum relative humidity and heavy rainfall events emerged as the dominant factors. During the stem canker phase, Aliabad showed the highest levels of disease incidence and severity in both years. Correlation analysis indicated that mild minimum temperatures, high relative humidity, and heavy rainfall wer strongly positively correlated with disease incidence and severity.
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References

AFSHARI-AZAD H., DALILI S. A. R., SALATI M., and AMINI-KHALAF M. A. 2008. Distribution of rapeseed blackleg disease in Iran. p. 199. Proceedings of the 18th Iranian Plant Protection Congress, 24-27 Aug. 2008. In Faculty of Agriculture, University of BU-Ali Sina Hamedan. (In Persian with English abstract).
AGHAJANI, M. A., SANAEI, M and AGHAJANI, M. 2019, Monitoring of important canola diseases in farms of Golestan province, First Iranian Congress of Plant Pathology. Karaj, Iran. https://civilica.com/doc/945279
CAMPBELL, C. L., & MADDEN, L. V. 1990. Introduction to Plant Disease Epidemiology. John Wiley & Sons. https://doi.org/10.1177/003072709001900219.
DENG, Y., LI, J. C., LYV, X., XU, J. W., WU, M. D., ZHANG, J., YANG, L., & LI, G. Q. 2023. Large-scale surveys of blackleg of oilseed rape (Leptosphaeria biglobosa) revealed new insights into epidemics of this disease in China. Plant Disease, 107(5), 1408–1417. https://doi.org/10.1094/PDIS-06-22-1304-RE
EL HADRAMI, A., FERNANDO, W. G. D., & DAAYF, F. 2010. Variations in relative humidity modulate Leptosphaeria spp. pathogenicity and interfere with canola mechanisms of defence. European Journal of Plant Pathology, 26 (2): 87-202. https://doi.org/10.1098/rsif.2007.1136
EVANS, N., BAIERL, A., SEMENOV, M. A., GLADDERS, P., FITT, B. D. 2008. Range and severity of a plant disease increased by global warming. J. R. Soc. Interface 5: 525-531. https://doi.org/10.1098/rsif.2007.1136
FAOSTAT. 2018. Food and Agriculture Organization of the United Nations. Available at: www.fao.org/faostat/ [accessed June 11, 2018].
FITT, B.D.L., BRUN AND H, BARBETTI, M. J. and RIMMER, S. R. 2006. World-Wide importance of Phoma Stem Canker (Leptosphaeria maculans and L. biglobosa) on Oilseed Rape (Brassica napus). European Journal of Plant Pathology. 114: 3-15. https://doi.org/10.1007/s10658-005-2236-4
GHANBARNIA, K., FERNANDO, W. G. D., & CROW, G. 2009. Developing rainfall- and temperature-based models to describe infection of canola under field conditions caused by pycnidiospores of Leptosphaeria maculans. Phytopathology, 99(7), 879-886. https://doi.org/10.1094/PHYTO-99-7-0879
HUA, L., SIVASITHAMPARAM, K., BARBETTI, M. J. 2007. Soil-borne ascospores and pycnidiospores of Leptosphaeria maculans can contribute significantly to blackleg disease epidemiology in oilseed rape (Brassica napus) in Western Australia. Australasian Plant Pathology. 36: 439-444. https://doi.org/10.1071/AP07047
HUANG, Y. J., & FITT, B. D. L. 2018. Effects of altitude on development of fungal diseases in oilseed rape (Brassica napus). Plant Pathology, 67(5), 1081-1090. https://doi.org/10.1111/ppa.12801
HUANG, Y. J., EVANS, N., LI, Z. Q., ECKERT, M., CHÈVRE, A. M., RENARD, M., & FITT, B. D. L. (2006).Temperature and leaf wetness duration affect phenotypic expression of Rlm6 mediated resistance to Leptosphaeria maculans in Brassica napus. Phytopathology, 96(3), 243–252. https://doi.org/10.1094/PHYTO-96-0243
KACZMAREK, J., KEDZIORA, A., BRACHACZEK, A., LATUNDE-DADA, A. O., DAKOWSKA, S., KARG, G., & JEDRYCZKA, M. 2016. Effect of climate change on sporulation of the teleomorphs of Leptosphaeria species causing stem canker of brassicas. Aerobiologia, 32(1), 39-51.
KEYPOUR, A., NAJAFI ZARRINI, H and ZAMAN MIRABADI, A. 2016. Evaluation of Resistance to Leptosphaeria maculans in Some Varieties and Species. Journal of Crop Breeding.7 (16): 27-33.
KOULBACK, A., & AUBERTO, B. 2016. Impact of heavy rainfall on the spread and severity of fungal diseases in canola fields. Journal of Agricultural Research, 58 (4), 123-135.
MARCROFT, S. J., SOSNOWSKI, M. R., SCOTT, E. S., RAMSEY, M. D., SALISBURY, P. A., & HOWLETT, B. J. 2004. Crop Isolation, not extended rotation length, reduces blackleg (Leptosphaeria maculans) severity of canola (Brassica napus) in south-eastern Australia. Australian Journal of Experimental Agriculture, 44:601-606. https://doi.org/10.1071/EA02105
MIRABADI A., RAHNAMA K., SADRAVI M., SALATI M. 2009. Identification, distribution, and symptomology of the causal agents of rapeseed blackleg (Leptosphaeria maculans and Leptosphaeria biglobosa) in Mazandaran and Golestan provinces and determination of three common rapeseed cultivars susceptibility reaction. Iranian Journal of Plant Pathology, 45:285- 267. (In Persian with English abstract).
NASERI, B., DAVIDSON, J. A., & SCOTT, E. S. 2008. Effect of temperature, cultivar and plant tissue on germination of, and hyphal growth from, ascospores of Leptosphaeria maculans. Australasian Plant Pathology, 37, 365–372.
NASERI, B., DAVIDSON, J. A., & SCOTT, E. S. 2009. Maturation of pseudothecia and discharge of ascospores
of Leptosphaeria maculans on oilseed rape stubble. European Journal of Plant Pathology, 125, 523–531.
RAZZAQ, K., DEL RÍO MENDOZA, L. E., BABAKHANI, B., AZIZI, A., RAZZAQ, H., & RAHMAN, M. 2025. Integrated Management Strategies for Blackleg Disease of Canola Amidst Climate Change Challenges. Journal of Fungi, 11(7), 514. https://doi.org/0.3390/jof11070514.
SPRAGUE, S. J., GRAHAM, J. M., BRILL, R., MCMASTER, C., 2018. Infection of Brassica napus after stem elongation by Leptosphaeria maculans (blackleg): disease progression and yield loss. 20th Australian Research Assembly on Brassicas.
STEEL, R. G. D., & TORRIE, J. H. 1980. Principles and Procedures of Statistics: A Biometrical Approach (2nd Ed.). McGraw-Hill. Leptosphaeria maculans and determination of aggressive new pathotypes canola Phoma stem canker in north Iran. Journal of Plant Protection 3:296–311. https://doi.org/10.22067/jpp.v0i0.58948
TRAVADON, R., BOUSSET, L., SAINT‑JEAN, S., BRUN, H., & SACHE, I. 2007. Splash dispersal of Leptosphaeria maculans pycnidiospores and the spread of blackleg on oilseed rape. Plant Pathology, 56 (4), 595–603. https://doi.org/10.1111/j.1365-3059.2007.01583.x
VAKILI, Z., RAHNAMA, K., RAHNEMA, M. 2013. The Comparative growth and determination of the isolates reaction of Sclerotinia sclerotiorum on oil seed rape cultivars. International Journal of Agronomy and Plant Production. 4 (5), 928-935.
VAKILI-ZARJ Z, RAHNAMA K, NAROLLAH-NEJAD S, YAMCHI A. 2017. Molecular identification of
WANG, Y., STRELKOV, S.E., & HWANG, S.F. 2020. Yield losses in canola in response to blackleg disease. Canadian Journal of Plant Science. https://doi.org/10.1139/CJPS-2019-0259. https://doi.org/10.1139/cjps-2019-0259.
WEST, J. S., BALESDENT, M. H., ROUXEL, T., NARCY, J. P., HUANG, Y. J., & FITT, B. D. L. 2001. Epidemiology of Leptosphaeria maculans (phoma stem canker) on oilseed rape in France, the UK, and Australian Plant Pathology, 50, 10–27. https://doi.org/10.1046/j.1365-3059.2001.00558.x.
YILAN, Z. 2004. Biocontrol of Sclerotinia stem rot of Canola by bacterial antagonists and study of biocontrol mechanisms involved. Master of Science thesis. Winnipeg, Manitoba, Canada. University of Manitoba. Department of Plant Science. 137 pp
 
Applied Entomology and Phytopathology
Volume 93, Issue 2
March 2026
Pages 154-179

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