جستجوی مقالات مرتبط با کلیدواژه "early maturing hybrids" در نشریات گروه "زراعت"

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.

Nine new early maturing maize hybrids along with KSC301 as the check, were evaluated in six locations Karaj, Isfahan, Ardebil, Kermanshah, Sari and Khoramabad for two years 2001 and 2002. The experiments were conducted in a randomized complete block design with four replications. Each experimental unit was four rows spaced 75cm apart and 36cm within the row. Combined analysis of variance was carried out and stability statistics were also determined based on ten environments. Effects of environment, genotype and genotype environment interaction on grain yield was significant at 1% probability level. The stability parameters of ecovalance (W2i), stability variance (σ2i), regression coefficient (bi) and deviation from regression (S2di) were calculated. Comparison of mean yield using Duncan’s test showed that maximum grain yield belonged to hybrids (K1264/5-1 K 615/1) and (K 1263/17x S 61) with 10.25 and 9.98 tha-1, respectively. Hybrids (K 1728/8 K 615/1) and (K 2331
K 1263/2-1) both with grain yield of 9.73 tha-2 did not show significant difference with other hybrids. Overall stability analysis showed that hybrid (K 2331 K 1263/2-1) had acceptable mean yield and stability compared to the check hybrid and the other hybrids across the ten environments.