Analysis of six agronomic characteristics in spríngwheat

Mario Mellado Z.1

Mean values and simple correlation coefficients between grain yield and five agronomic characteristics of spring bread wheats were studied. Data from the Wheat Breeding Program at the Quilamapu Exp. Sta. (INIA, Chillán), during the 1975-1984 period, were used. The variables studied were: grain yield, mature plant height, vegetative period, percentage infestation with Puccinia striiformis and with P. recondita, and hectolíter weight.
Conclusions were:
- Average grain yield of the germplasm analyzed varied from 3,200 to 6,800 kg/ha, with the higest values in the last three years;
- The majority of the germplasm is semidwarf,as a consequence of the dwarfing genes Rht1 or Rht2, belonging to Norin 10-Brevor 14;
- Rust incidence, principally P. striiformis was permanently present under the natural conditions of the Quilamapu Exp. Sta. (Chillán);
- P. stríiformis and hectoliter weight were the parameters with the highest simple correlation with grain yield.

1 Estación Experimental Quilamapu (lNIA), Casilla 426, ChiIlán Chile.