Effect of Moisture and Temperature on the Survival of Sclerotia of Sclerotium rolfsii in Soil

Abstract

The sclerotia of Sclerotium rolfsii Sacc. survived in natural soil for 225 days under controlled moisture at 50 % water holding capacity (WHC) after which there was a progressive reduction in the population of viable sclerotia. At 390 days only 48 % were recovered. Sclerotia survived well at moisture contents upto 75 % WHC but at 100 % the population declined rapidly and none were recovered after 60 days. The contents of the sclerotia were found to lyse without germination leaving hollow rinds. Such lysis was found to be favoured between 25 and 40 °C. At and below 20 °C no such lysis was recovered and more than 80 % sclerotia were recovered even after 60 days. ZusammenfassungDer Einflufi der Feuchtigkeit und der Temperatur auf das Uberleben von Sclerotium ro/Zsii-Sklerotien in der Erde Sclerotium rolfsii Sacc.-Sklerotien in natiirlicher Erde iiberlebten 225 Tage unter kontrollierten Feuchtigkeitsbedingungen, die einer 50 %igen Wassersattigung (WHC) entsprachen, danach trat eine fortschreitende Reduktion der lebenden Sklerotienpopulation ein. Bei 390 Tagen konnten nur 48 % der Sklerotienpopulation wiedergefunden werden. Die Sklerotien iiberlebten Feuchtigkeitsbedingungen bis zu 75 %iger WHC gut, aber bei 100 %iger WHC baute sich die Population sehr schnell ab und nach 60 Tagen wurden keine Sklerotien wiedergefunden. Der Inhalt der Sklerotien loste sich, ohne zu keimen, auf, um hohle Rinden zu hinterlassen. Es wurde festgestellt, dafi die Auflosung bei Temperaturen zwischen 25 und 40 °C begiinstigt wurde. Bei Temperaturen um oder weniger als 20 °C wurde eine Auflosung nicht ermittelt und mehr als 80 % der Sklerotien wurden auch noch nach 60 Tagen wiedergefunden. U.S.

Effect of organic amendments on sclerotial germination, mycelial growth, and Sclerotium rolfsii-induced diseases

“…Used at low rates, benzaldehyde can act as a spore germination-inducing agent, can stimulate and select for biological control microorganisms against S. rolfsii, and can act as a fungicidal or fungistatic compound when used at high concentrations (Soler-Serratosa et al, 1996). Some research has been done on the effects of temperature, moisture, pH, salinity, fungicides, amendments, and volatile compounds on the germination of S. rolfsii sclerotia (Beute & Rodríguez-Kábana, 1981;Maiti & Sen, 1988;Canullo et al, 1992). However, there is limited information available on the effect of benzaldehyde, kudzu, velvetbean, and pine bark on the sclerotial germination and mycelium growth of S. rolfsii on soil.…”

Factors influencing the incidence of basal stem rot and blight disease caused by Sclerotium rolfsii in vegetable cowpea and its management using botanicals

“…The standardization of moisture percentage for the optimum growth of the fungus was performed as per the methodology described by Maiti and Sen (1988). Sterilized soil was filled in plastic cups (400 ml capacity).…”

Sclerotinia rot of rapeseed mustard: A comprehensive review

“…Few studies have also quantified the sclerotial survival of Sclerotinia species at different depths and duration in soil (Pande et al, 2008;Cosic et al, 2014). The viability of sclerotia on the surface declined rapidly due to the alternate wetting and drying of soil (Maiti and Sen, 1988). Survival was significantly influenced by depth of burial and by sclerotial treatment before burial.…”