رقابت در كشتهاي خالص و مخلوط ذرت و سويا به روش عكس عملكرد

Competition study in pure culture and intercropping of corn and soybean using reciprocal yield method

A study was performed in 1997 on the experimental field of Faculty of Agriculture, Tabriz University, in order to study competition and find a model for intercropping of corn and soybean. The experiment was factorial based on randomized complete block design with 3 replications. Corn and soybean densities constituted the factors under study. In this experiment, the relationship of density with yield per plant and yield per meter square were obtained. The growth curve of corn responding to density was asymptotic but the curve for soybean felled at first by increasing density and finally became constant. Competitive models were also fitted by Spitters method. It was shown that inter-species competition of corn was greater than intra-species competition. In the basis of relative competitive ability of corn, the effect of one plant of corn on its reciprocal biological and grain yield was equal to the effect of 33.55 and 74.72 plants of soybean on the reciprocal biological and grain yield of corn. For soybean, each 0.122 and 0.0022 plants of corn had an effect equal to one plant of soybean reciprocal biological and grain yield of soybean, respectively.