بررسی اثر علف‌کش‌های دومنظوره بر برخی از شاخص‌های فیزیولوژیکی گندم در مراحل مختلف فنولوژی

In order to examination of dual purpose herbicides on some wheat physiological indexes in different stages of phenology of this corp, an experiment was conducted in 1386-1387, in kordkoy, Golestan province with dry farming condition. This study was performed as factorial in randomized complete block design with 2 factors and 4 replications. The first factor included the type of herbicides: Shovalee (iodosulfuron plus mesosulfuron), Apyrous (Sulfosulfuron), Topik plus Granstar (Tribenuron methyl plus Clodinafop propargyl), Atlantis (idosulfuron plus mesosulfuron plus Surfactant) and Total (Metsulfuron methyl plus Sulfosulfuron ) and the second factor was different stages of wheat phenology on the base of Zadoks division, that is: 2-3 leaf stages, tillering, flowering and physiological ripening of wheat. The results showed that tested herbicides had undesirable effect on seed yield, height and dry weight of wheat in some stages of phenology, and sometimes led to leaf burning. Average comparison of the herbicide type and the stages of wheat phenology, and interaction of these two factors in evaluation of seed yield showed that Shovalee, Apiruos,Topic+Granstar, Atlantis and Total herbicides decreased yield seed in 2-3 leaf stages of wheat, which the most decreasing effect was related to Shovalee that had a significant difference with other herbicides. Examination the height of wheat shrub showed that Shovalee had the most decreasing effect on this characteristic, in 2-3 leaf stages. Calculating the correlation coefficient of tested characteristics indicated that seed yield had a positive and significant correlation with dry weight, in fourth week after poisoning, and with the number of tillering, height of shrub, weight of 1000 grain weight, the number of seed in each spike, the length of spike in 1 and 5% level, and showed the most correlation coefficient with height.