Management of Johnsongrass (Sorghum halepense (L.) Pers.) in Alfalfa Cultivation Areas of Iğdır Province

Abstract

One of the most important weed species that reduces productivity and quality in alfalfa (Medicago sativa L.) crops is Sorghum halepense (L.) Pers. (Johnsongrass). Therefore, it is of great importance to control this weed in alfalfa cultivation areas. In this context, this study was carried out in 2022-2023 to determine the frequency and density of S. halepense, which is a problem in alfalfa cultivation areas in Iğdır province, and the effects of some herbicides with different active substances on S. halepense and alfalfa yield. Within the scope of the study, surveys were carried out in 50 alfalfa cultivation areas in Iğdır province and its districts. In addition, herbicides with the active substances Quizalofop-p-ethy (Q), Haloxyfop (R) methyl ester (H) and Propaquizafop (P) and the mowing process with the Q+H mixture were compared with each other in order to determine their effects on S. halepense and alfalfa yield. As a result of the study, at the end of both years, theoccurrence frequency of S. halepense in alfalfa cultivation areas in Iğdır province was determined as 92.25% and its density was 48.15 plants/m2. In the study, the effectiveness rates of herbicides on S. halepense varied between 95% and 100% in the last assessment. The effect of the herbicides used in the study on S. halepense dry weight varied between 78.90% and 91.56%. As a result of the study, herbicides with different active ingredients and their mixtures resulted in a statistical difference of 1% (p