Rapeseed mustard is the third most important oilseed product in the world after soybean (Glycine max) and palm (Elaeis guineensis Jacq) in the global agriculture and India is the third largest. producer with an overall contribution of 28.3 percent of area and 19.8 percent of production (Shekhawat et al., 2012; Bandopadhyay et al., 2013). Brassica juncea L. (Czern & Coss.) is an important oilseed plant traditionally cultivated throughout the Indian States, with special reference to the marginal and sub-marginal soils of the Eastern, Northern and North-Western States, in as pure crop as well as intercropping (mixed crop). crop). The low temperatures and humid climate of winter are an important factor for the growth and productivity of mustard in these regions (Rathi and Singh, 2009). Despite the considerable increase in productivity and production, this crop still faces multiple abiotic and biotic challenges in farmers' fields. Destructive diseases of rapeseed mustard include those caused by fungi, bacteria, viruses and phytoplasmas. Among them, sclerotinia stem rot is the most serious fungal disease that causes maximum damage to Indian mustard (Rakesh et al., 2016). Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get the original essay Sclerotinia rot or white rot caused by Sclerotinia sclerotiorum (Lib. ) de Bary, is a cosmopolitan and destructive soil-inhibiting plant pathogen. The pathogen shares a wide host range consisting of more than 500 plant species, including 278 genera distributed in 75 families of dicotyledonous plants and several monocotyledonous plants (Boland and Hall, 1994; Willetts and Wong, 1980; Purdy, 1979; Steadman, 1983; Sharma, 2014; Sharma et al. destructiveness is mainly present in temperate and sub-temperate zones of the world It is believed to inflict considerable reduction in the yield of economically important crops (Boland and Hall, 1998; Fernando, 2004; Malvarez et al. , 2007; Parveen). et al., 2007). Extensive literature is available on various aspects of S. sclerotiorum in several crops, but its information on rapeseed mustard is reviewed here in the following paragraphs. Causal Pathogen: Sclerotinia rot or white stem rot of mustard is caused by a non-sporous homothallic fungus present in the soil, i.e. Sclerotinia sclerotiorum (Bolton et al. , 2006). The pathogen was first described by Madame MA Libert (1837) under the name Peziza sclerotiorum. Later in 1870, Fuckel created a new genus Sclerotinia and renamed it Sclerotinia libertinia. In 1945, Whetzel proposed a new family of Sclerotiniacae and also provided the key to the diagnosis of the genera to which it belongs. However, the name and authority of the fungus has generally been accepted as Sclerotinia sclerotiorum (Lib.) de Bary due to de Bary's significant contribution to his literature. S. sclerotiorum is a necrotrophic pathogen composed of hyaline, septate, branched, and multinucleate hyphae; the mycelium may appear white to beige in culture plates (Boltan, Thomma, & Nelson, 2006). The pathogen goes through four stages in its life cycle, viz. sclerotia, apothecia, ascospores and mycelium (Purdy, 1979). It can be a thick carpetmycelial in restricted colonies, which later produces white mounds of mycelium, covered with small droplets of liquid, these mounds later coalesce to form dark-colored structures, namely sclerotia, which are resistant to environmental stresses (Willetts and Wong, 1971). ), and also act as primary survival structures (Coley-Smith and Cook 1971; Willetts and Wong 1980). The fungus spent 90% of its lifespan as dormant sclerotia (Adams and Ayers, 1979). Sclerotia can survive in one or more of three ways: myceliogenic, corpogenic and sporogenic, but corpogenic and myceliogenic germination occurs in S. sclerotiorum (Tourneau, 1979). The germinal sclerotia give rise to 2 to 5 columnar structures, stipes or primordials which are branched dichotomously. Apothecia initially appear in the cortex or spinal cord as clusters or nests of intertwined brown to hyaline hyphae and at the ends tiny brownish funnel-shaped cups or apothecia are produced, measuring 6 to 9 mm in diameter . They are usually raised 6 to 10 mm above the soil surface and become darker with age. The apothecia contain cylindrical asci measuring 108-153 x 45-10 microns. Each ascus forms eight unicellular, oval hyaline ascospores, measuring 7 to 16 x 3.6 to 10 microns. These ascospores are ejected violently through the apical pore of the ascus and contribute to the spread of diseases during the crop season. Initiation of the disease cycle occurs by means of sclerotia, a dormant multihyphal structure that can tolerate a diverse range of adverse weather conditions over several years. The germination method depends on environmental conditions (Saito, 1973; Joens, 1974; Kosasih and Willetts, 1975; Steadman, 1983; Sharma and Meena, 2011; Willets and Wong 1980) and plant cover (Bardin and Huang 2001). Crop infection is associated with senescent flowers, which provide an energy source for germinating ascospores (Cook et al. 1975), suggesting that crop phenology plays an important role in the occurrence of this disease in certain cultures (McLean 1958; Natti 1971). ; Abawi and Grogan 1975; Abawi et al. 1975; Kruger 1975; ). The pathogen survives (winters) in the soil and also in the host by means of a hard dormant structure, i.e. sclerotia. It consists of a light-colored interior called pith and a protective black outer covering called rind. The crust is very resistant to degradation due to the presence of melanin; the sclerotia contain fungal cells which contain an abundance of -glucans and proteins. In S. sclerotiorum, the development of sclerotia can proceed in three distinct stages (Townsend and Willetts, 1954): (i) Initially, the formation of small mounds, i.e. intertwined hyphae developed due to of the repeated branching of long primary areal hyphae. (ii) Development, increase in size, and (iii) Finally, the sclerotia mature, which is characterized by the appearance of dark-colored or melanized hard structures, internally consolidated, which can often bear droplets when mature. Morphological and biochemical differentiations accompany these phases. All stages of sclerotia development are affected by many factors such as photoperiod temperature, aeration and nutritional status, etc. , the production of growth hormones such as oxalic acid (OA) may show some measure of correlation with development and play an essential role in the development of disease (Zhou and Boland, 1999; Chet and Henis, 1975; Donaldson et al., 2001). The development of sclerotia is a.