Sclerotium blight resistance (tolerance) of apetalous rape lines in Brassica nupus.

The apetalous rape lines and rape varieties with petals were identified by the natural infected nursery and artificial inoculation to know sclerotium blight resistance (tolerance) of apetalous rape varieties after petals disappearance. The results showed that the leaf infected rate of apetalous rape lines was obviously lower than that of rape varieties with petals under the natural infected nursery,the damage degree of sclerotium blight of apetalous rape lines was lower or similar to Huyou 15 with petals,a known rape variety with high resistance (tolerance) to sclerotium blight during the maturity stage,and lower than that of Youyan 7,a hybrid rape variety with poor resistance to sclerotium blight. The identification results from the artificial inoculation test indicated that the spot spread speed of apetalous rape lines was quicker than that of Huyou 15,which expresses that the apetalous rape line itself has no high resistance to sclerotium blight and the action of avoiding disease mainly depends on petals disappearance obviously.