Histopathological Studies of Rhizoctonia solani Infection Process in Different Cultivars of Mungbean [Vigna radiata (L.) Wilczek]

Histopathological patterns and differential behavioural of Rhizoctonia solani causing sheath blight in rice (Oryza sativa L.)

“…Earlier studies only examined control laboratory conditions (Bashyal et al, 2018;Basu et al, 2016;Marshall & Rush, 1980). In vivo, mycelial agar disc bioassay was utilized to compare the resistance response of wild-type and transgenic rice lines infected with the ShB pathogen.…”

“…The infection process of R. solani generally starts with the growth of the mycelium on the sheath surface. During the pre‐penetration stage, a single hypha branches into a cluster and forms infectious structures such as infection cushions and lobate appressoria with swollen hyphae that penetrate through the inner sheath surface (direct penetration) or hyphae that penetrate through stomata (indirect penetration) (Bashyal et al, 2018; Basu et al, 2016). Complete management of sheath blight is challenging due to several reasons, including broad host range and relatively high genetic diversity of the R. solani pathogen, dormant sclerotia in soil or mycelia in plant debris can survive for several years (Smith & Dilday, 2002), and no rice germplasm has been found to be completely resistant to sheath blight because it is governed by multiple genes (Taheri & Tarighi, 2011).…”

“…Further, although the significance of sheath blight, there is only a few research studies carried out due to the reality that under the field condition, it is very difficult to observe every step of rice-R. solani interaction. All previous studies explained only superficially symptoms, disease cycle and infection stages in one or few cultivars (Bashyal et al, 2018;Taheri & Tarighi, 2011) but not investigated all histopathological and microtomy aspects, root microscopy, artificial screening of cultivars/line, disease severity and symptoms differentiation in moderately resistant as well as highly susceptible cultivars at different time intervals under field condition. Comprehensive knowledge of host-pathogen interactions, recognition, penetration, infection, incubation and colonization can be a useful approach for the development of appropriate management tactics in a sheath blight resistance breeding program.…”

Influence of Temperature on the Pathogenesis and Gene Expression of Rhizoctonia solani Causing Web Blight/Wet Root Rot Disease in Mungbean

“…The condition for these sets were temperature of 20  C, 25  C, 30  C and 35  C, relative humidity (85%) and illumination (alternate dark and light period) of 12 hrs. To study the virulence of different isolates on susceptible genotype Pusa Vishal, isolates were multiplied on sorghum grains and 15 days old inoculums was mixed on soil at the rate of 10 g/kg of soil (Bashyal et al 2018). Disease incidence was observed at the interval of 15 days and final data was calculated as mean value of five observations.…”

“…Polysaccharide synthase is responsible for the appressorium formation (Rioux et al 2011). Three maj or events involved in pathogenesis process of R. solani in mungbean are early host contact or attachment and penetration, adjustment to the host environment and proliferation of pathogen through necrotic tissues (Bashyal et al 2018). Higher expression of β-1, 3 glucan hydrolase and Polysaccharide synthase at early hrs of inoculation i. e. 24 and 48 hrs at 25  C suggests the early colonization and pathogenicity at this temperature.…”