Investigation of important agronomic traits of bread wheat genotypes via analyzing to factors

In order to categorize genotypes of bread wheat according to the evaluated traits, an experimental in agronomic year of 2011-2012 in the research farm of Islamic Azad University of Ardabil Branch in factorial form with 30 genotypes and two drought stress levels with completely randomized block design was conducted. This experiment was repeated three times. In drought stress treatments the irrigation was eliminated after pollination. In analyzing to the factors, four factors with high Eigen values were selected, where they have been making 74.285 percent of the main data variance. Based on the analyzing to the factors results, most of traits have a high coefficient of the same behaviors and the results show that the number of selected factors was appropriate to our aim and the selected factors have been able to justify and interpret the traits changes properly. The first factor have been able to explain about 28.101 of the main variables and in this factor, the spike length, spike weight, biomass weight, number of grains per spike and grain weight per spike got large coefficients and was named the effective factor to the spike traits. The traits of first factor are highly correlated with each other; therefore these factors can play an important role in achieving desirable traits. The second factor explained and justified about 17.323 percent of the variations of the main data. In these factors, traits including number of days to pollination, number of days to heading, number of days to ripening, grain filling period and harvest index were studied and it was labeled as phonological traits affecting factor. The third factor was able to explain 15.182 percent of the variations. The spike per square meter and grain yield were affecting this factor, and it was named as yield factor. The fourth factor explained 13.678 percent of the variation. Tiller number, plant height and seed weight were affecting this factor and it was named as plant height affecting factor.