VÍCTOR VOLKE H.1 Y OSVALDO INOSTROZA U.2
Nitrogenand phosphorous are 2 of the principals production factors for wheat in mayority of "trumao" soils type. Differents amounts of nitrogen and phosphotous were used on a trial to study the effect of both on yield of a winter wheat variety, Capelle Desprez, through of the respose of these nutrients on yield components and others of its characteristics.
The trial was making on a "trumao" soil type of the Vilcún Association, at the Carillanca Agricultural Research Station in Temuco.
Each characteristics of the wheat was statistically analized with a multiple regression analysis using the second grade polynomial model. The lineal correlation analysis was used for yield and characteristics, and between sorne of its.
There was a positive effect of nitrogen and phosphorous on tillering; negative effects of nitrogen (not statistically significant) and phosphorous were observed in the number of grains per head; a negative effect of nitrogen and a positive effect of phospho rous was observed on the weight of grains; a negative effect of nitrogen and a positive effect of phosphorous was found at the time of ripening, which means delayed and advanced the time of ripening respectively, measured by the quantity of moisture in the grain just before maturity and also by a difference in the number of days needed to reach maturity. Finally, positive effects of nitrogen and phosphorous were observed on yield.
The coeficient of multiple determination equations went from 0,522 to 0,987.
On the other hand, a positive correlation was found in yield with tillering and with height, and a negative correlation with the number of grains per head. No correlation was determined in yield with the weight of grains, with moisture just before maturity, and with the difference in the number of days needed to reach the harvest stage.
1 Ingeniero Agrónomo, Proyecto Fertilidad de Suelos, Estación Experimental Carillanca, Instituto de Investigaciones Agropecuarias. Profesor Cátedra Conservación de Recursos Renovables, Facultad de Ciencias Agrarias, Universidad Austral de Chile
2 Ingeniero Agrónomo, Proyecto Fertilidad de Suelos, Estación Experimental Carillanca, Instituto de Investigaciones Agropecuarias. Profesor Fitotecnia, Centro Universitario de Temuco, Universidad de Chile.