Geographical distribution and host range of Sclerotinia sclerotiorum causing stem rot of crucifers Mehta Naresh*, Meena P.D.1, Saharan G.S. Department of Plant Pathology, CCS Haryana Agricultural University, Hisar- 125004 1ICAR- Directorate of Rapeseed-Mustard Research, Bharatpur-321001 *E-mail: nareshmehta282@gmail.com
Online Published on 28 August, 2023. Abstract Crucifers (Family Cruciferae) include a major group of oilseeds and vegetable crops contributing significantly in the economy of agricultural crop commodities all over the world and have major share in edible quality oil and vegetable production. The Brassica genus is a member of Brassicaceae (Cruciferae) which contains 39 species. Stem rot of crucifers is caused by Sclerotinia sclerotiorum (Lib.) de Bary, a soil borne hemibiotrophic pathogen. It was initially described as Peziza sclerotiorum (Lib.) which is considered as the major species of genus Sclerotinia causing heavy yield losses in cruciferous crops all over the globe. The establishment of this pathogen has gone through several phases of research to recognize Sclerotinia species as disease causal agent, its family Sclerotiniaceae, distribution of Sclerotinia species and its type species S. sclerotiorum (Lib.) de Bary. The pathogen occurs all over the globe where crucifers are grown widely. As per distribution map of plant diseases of CABI, UK, it is distributed in every continent covering more than 92 countries. The crucifers’ pathogen S. sclerotiorum has extra ordinary broad host range infecting more than 900 plant species from more than 98 families. According to USDA database, it is associated with 2048 host species and varieties. Most of the hosts are dicotyledonous herbaceous plants but several of them also belongs to monocots. The molecular evolutionary features of Sclerotinia as host generalists have been revealed after sequencing of its genome. The oxalic acid production gene is expressed 10-300 times higher in host generalists than in the host specialists, concomitant with accumulation of a larger amount of oxalic acid during infection. The molecular determinants of host range indicated preference of S. sclerotiorum for dicotyledonous plants but few monocots have also been reported. The pathogen produces ethylene including peptide 1 like proteins (NLPs) which elicit cell death and subsequent necrosis in most dicots and some monocots. The NLPs cause necrosis by binding to a specific form of the membrane lipid glycosylinositol-phosphorylceramid, which is wide spread among dicots but rare among monocots. The host records, which have not been reported in the publication of Saharan and Mehta (2008), are presented in this review. Top Keywords Sclerotinia sclerotiorum, Geographical distribution, Host range, Molecular virulence determinants. Top |