Screening for resistance to Sclerotinia stem rot of chickpea

摘要

In an annual routine monitoring visit of chickpea fields for diseases occurring on promising breeding lines in Syria, Sclerotinia stem rot caused by Sclerotinia sderotiorum was found in more than 20% of the fields in which the trials were planted. Thedisease incidence ranged from S to 50% and none of the lines showed good resistance. A program was initiated to start screening chickpea lines with known resistance to Fusarium wilt caused by Fusarium oxysporum f.sp. ciceris, to identify lines with combined resistance to Sclerotinia stem rot. A detached shoot technique was used to determine the preliminary reaction of chickpea genotypes to infection by S. sderotiorum. Results using this technique under controlled conditions in the growth chamber, showthat out of 15 chickpea genotypes evaluated, 5 showed some resistance to Sclerotinia stem rot. This was exhibited by delayed initial infection, restricted lesion development and no production of sclerotia. These results will be further confirmed under field conditions in a naturally infected field plot which has a high inoculum density of S. sderotiorum. Any line confirming the observed resistance will be used in a planned crossing program for multiple resistance to the 2 soilborne pathoens.