Effetti della densità di semina e della concimazione azotata sulla produzione del triticale

In the year 1981-82 a factorial trial of nitrogen fertilization (80, 120, 160, kg ha-1of N) and sowing rates (300, 350, 400 viable seeds per m2) has been carried out on three triticale lines in two environments of Sardinia (Oristano and Sassari). Equal N rates have been applied to a durum wheat at 350 sowing rate. The limited water availability in the soil, especially during the grain filling, has negatively affected the DM accumulation processes more markedly in the high ear n. per m2thesis. In both sites the n. of plants increased with increase in seed rates and there was a greater correspondence between theoretical and reaI density at Oristano. Indipendently of the varieties and N rates, at Sassari yields have been slightly increasing with increase in sowing rates to which variations in the ear n. per m2correspond in the same way, while at Oristano significant production increase has been achieved only by N80 rate owing to the seed rate. At Sassari, indipendent of sowing rates, triticale grain yields have been slightly increasing with increase in N rates. At Oristano production variation has not been achieved with lower sowing rates, decrease has been observed with more then N 80 kg ha-1at higher sowing rate. A slightly higher triticale grain production compared with durum wheat has been achieved restricted to Oristano.