Greenhouse and field evaluation of rapeseed cultivars and lines for resistance against Sclerotinia sclerotiorum (Lib.) de Bary

Abstract

Sclerotinia stem rot (SSR) of rapeseed caused by Sclerotinia sclerotiorum (Lib) de Bary is one of the most
important disease of rapeseed- mustard causing significant losses in both quality and quantity of seed. In
recent years, the disease has become very serious in northern Iran. In present investigation, 11 rapeseed
(Brassica napus L.) genotypes were evaluated for their reaction against SSR under greenhouse and field
conditions. The results of green house study recorded disease index (DI) of 52.8, 54.5, 55.6, 56.1 and 56.1
respectively, in genotypes RGS003, HAYOLA 401¡SARIGOL¡ RASOPT and ZAR401. Genotypes19SAR-
3, RG3OPT, RG3401 and RW19 recorded considerably higher DI 69.4, 66.7, 66.0 and 63.9 respectively.
Under field conditions genotypes RASOPT, HAYOLA 401, RGS003, SARIGOL and ZAR401also showed
lowest infection percent of 5, 8, 11, 11.5 and 11.5 respectively, while RG3SAR, RW19, RG3401 and
19SAR-3 genotypes proved to be more susceptible to SSR. Reaction of our study showed similar reaction of
all genotypes under both greenhouse and field conditions.