واکنش ژنوتیپهای زودرس ذرت به بیماری سیاهک معمولی

Abstract

Common smut is an important disease of maize that occurres in many maize growing countries as well as in Iran and causes considerable damages on yield. Damage of the disease varies by race of the pathogen, susceptibility of host, agronomic procedures and nitrogen fertilizers application on crop. Damages up to 50% on susceptible cultivars have been reported frequently. Control of the disease through common methods is difficult and use of resistant cultivars is the best method for control of the disease. In the present study response of 29 maize genotypes including 16 hybrids and 13 parents to prevalent races of the pathogen was evaluated in field condition in Karaj and Isfahan in 2014. All ears of plants in each plot were inoculated with a suspension of sporidia of five isolates of the pathogen and disease severity was scored at the end of the season and respose of genotypes was evaluated. Based on the results, only line S61 was resistant and the remaining were moderately resistant except OH43/1-42 and KE 78008/212 which were highly susceptible. Among hybrids, KSC 201 (K1263/17 × S61) was highly resistant, KSC 400 (KE 72012/12 × KE 1263/1), KE 75016.321 × K 1264/5-1 and KSC 260 (K 615/1 × K 1264/5-1) were resistant and the remaining hybrids were moderately resistant or moderately susseptible.