Abstract

The national project of  Iran aimed  to study  the etiology of bean decline disease and  the  induction of bean resistant cultivars to the disease. Samples of 75 infected bean plants (300 in total) were collected from  four  growing  locations  in  three  provinces  of  Northwest  Iran.  The  isolated  pathogens  were Fusarium solani (41.6%), Fusarium oxysporum (32%), Fusarium sambucinum Fuckel (18%), Rhizoctinia solani  (5.4%)  and  Pythium  debaryanum  (2.7%).  Sufficient  inoculums of  three  Fusarium  species were prepared in chaff medium and added to the natural field soil to obtain 2000 cfu g1 /soil of each species in treated soils. Ten local and international bean cultivars (Emerson, Dehghan, Joules, Akhtar, Naz, Sayad, Golden, Keshavarz, Daneshkadeh  and Soheir L-  90) were  sown  into  50  infested  and  50 non-infested pots;  then  their  growth  and  yield productions were  evaluated.  ‘Naz’ was  the most  resistant  cultivar, which produced  the highest dry matter yield  (175 g  /15 plants) and  the  lowest yield  reduction  (9.3%), while ‘Joules’ had moderate production (110 g/15 plants) and loss (31.7%), and ‘Soheir L-90’ showed the highest susceptibility with  the  lowest  (60 g/15 plants) and highest yield  loss  (52%). Thus,  the  results show  the most  important bean  cultivar  resistant  to Fusarium decline disease, which  is  significant  in favor of yield productions.