# Correlations of yield and grain yield components of winter wheat varieties

Institute for the Application of Science in Agriculture, Belgrade (1)

Institute for Medicinal Plant Research “Dr Josif Pančić” (2)

ECO-LAB, Padinska Skela, Belgrade (3)

**Abstract:**

Mean positive correlation (r = 0,47**) between grain yield and number of plants per m² and strong correlation between grain yield and number of spikes per m² were established (r = 0,55**). Weak correlation was established between grain yield and productive tillering (r = 0,24**). Strong positive correlation (r = 0,51**) is between the number of spikes per m² and productive tillering, as well as between the number of plants per m² and number of spikes per m² (r = 0,68**). Very weak negative correlation (r = -0,12*) is between productive tillering and the number of plants per m². Regression equations of grain yield and other investigated traits, on the level of significance 5% and 1%, have linear form. By increasing one plant per m², the number of spikes for one per m², productive tillering for one, grain yield will be increased for 0,006 t/ha, 0,005 t/ha and 1,174 t/ha on the average. The other regression equations between the number of spikes per m², number of plants per m² and productive tillering have linear form. By increasing one plant per m² and productive tillering for one, the increase of number of spikes per m² is 1,087 and 312,21 on the average. By increasing the number of plants per m², productive tillering is reduced for 47,59 on the average.