Plonowanie i jakość ziarna jęczmienia nieoplewionego w zależności od terminu siewu i poziomu nawożenia azotem

Dariusz Gozdowski

Zdzisław Wyszyński

Maria Kalinowska-Zdun

Abstrakt

In the years 2000–2002 at the Experimental Station of Warsaw Agricultural University at Chylice the influence of sowing date and nitrogen rates on the yielding and quality of grains of spring barley naked cultivar Rastik was investigated. The aim of this experiment was evaluation of yielding of this form of barley in central Poland conditions (low coefficient of soil quality, frequent shortages of rainfall) depending on 2 agronomical factors: date of sowing and rate of nitrogen fertilization. These factors very strongly modified the canopy and yielding of hulless barley. During the experiment there was shortage of rainfall in spring. In 2000 from April to June there was 43.5 mm of rainfall, in 2001 there was drought in May and June and in 2002 in April and July. The experiment was established in a split-plot (A-B) design with 4 replicates on the IIIa class soil, good wheat complex (2000 and 2001) and on the IIIb class soil, very good rye complex (2002). Barley was planted after root plants with manure. The factors of the experiment were: A – sowing date (I – as early as possible depending on weather conditions of a year, II – delayed 3 weeks), B – nitrogen rate (0, 30, 60 and 90 kg N/ha). Delay of the sowing date decreased the grain yield in average by 1.1 t/ha (37%), which was caused by a decreased number of spikes per 1 m2, number of grains per spike and the mass of 1000 grains. Delay of the sowing date increased protein content but decreased the fraction of grains having diameter larger than 2.2 mm. The nitrogen rate did not cause important changes in the grain yield. Significant differences were between the yieldings at 60 kg N/ha and without N fertilization. At 60 kg N/ha fertilization then was a high number of spikes and the highest number grains per spike. Nitrogen fertilization did not cause significant changes in protein content and in the fraction of grains having diameter larger than 2.2 mm.