Investigation of correlation relations and analysis of path coefficients among yield and yield components of 77 potato colonies with witness of genotype Agria

Abstract

In order to investigate correlation among traits and analysis of it into cause effect relations in potato plant, a test was done, in agricultural year, 2012 in Ardebil natural sources and agricultural researches station on 77 potato colonies and Agria marker number witness in frame of completely random blocks project with three repetitions. In statistical analysis of this research, 12 important traits were investigated and analyzed. Results of analysis of variance showed that among colonies and studied Genotypes except for Mean Tuber weight per plant, percentage of tubers smaller than 35mm in diam, number of Tubers with diameter of 35-55 mm in diam, percentage of Tubers with 35-55mm in diam and percentage of tubers large than 55mm in diam, there is meaningful difference in 1and 5% probability level from view of all assessed traits. This indicates high genetic variety among colonies and Genotypes in order to choose for the given traits. Correlation coefficients indicate this that performance of node had a positive and meaningful relation with traits of Marketable tuber yield ,Tuber weight per plant, Tuber number per plant, Mean Tuber weight per plant, number of tubers smaller than 35mm in diam ,number of Tubers with diameter of 35-55 mm in diam, number of tubers large than 55mm in diam, percentage of tubers large than 55mm in diam and weight of marketable tubers per plant and with percentage of tubers smaller than 35mm in diam, a negative and meaningful relation was seen. Between these traits of node performance, it had highest correlation with Marketable tuber yield. Multiple regression analysis with step by step method for weight of sellable Tuber showed that the first entered variable was to model of Marketable tuber yield that was justified 0.914 of changes, lonely. The second variable of weight of node was in bush that with Marketable tuber yield, it reached statement coefficient to 0.926 and finally, statement coefficient of model reached 0.932 by entering number of tubers large than 55mm in diam. Analysis of causality of remained traits in regressive model showed that based on this analysis, weight of sellable Tuber had maximum direct effect with weight of sellable Tuber and after it, average Tuber weight per plant had direct and positive effect with Tuber weight per plant. So, the most important traits were clear as choice index to improve weight of marketable tubers per plant including, Marketable tuber yields, Tuber weight per plant and number of tubers large than 55mm in diam.