بررسی تاثیر قارچ کشها ی مختلف در کاهش میزان پوسیدگی ریشه چغندر قند

Sugar beet root rot is a major problem for farmers.Several ways have been suggested to control the disease including the use of chemicals. In this experiment some legal fungicides were used at two stages in two ways; furrow and mist (spray). The experimental design was factorial with two factors; factor (A): different fungicides (Roral TS, Topas, Flent, Metalaxil+Mankozeb, Raxil and no-fungicide) at six levels, factor (B): application method (furrow and spray) at two levels..The cultivar used in the experiment was Jolgeh (sensitive to root rot). The analysis of variance of %root rot contamination showed that the application methods were not significantly different.% Root rot contamination in furrow method (by an average of 39.07) was less than mist (spray) method (by an average of 40.63).There wasn's a significant difference between the application method of the fungicides but group comparison between fungicide application (by an average of 38.79) and check (no fungicide) shows a reduction of contamination by 45.07%. So that the application of two fungicides of Raxil (by an average of 33.45%) and the mix of Metalaxil + Mankozeb (by an average of 37.56% ) is indicative of positive effect of their application relative to the check (by an average of 45.07%). The ANOVA and mean comparison of the interaction between application methods of the fungicides showed that in spray method chemicals Raxil and Flent were more effective than the check and the chemicals Roral TS, Topas and the mix of Metalaxil + Mankozeb at controlling the sugar beet root rot and in furrow method the application of the mix of Metalaxil + Mankozeb showed the least contamination by an average of 30.55%.