Results of studies have shown that yield increased achieved as effect of supplemental irrigation of spring or winter cereals are similar. Yield increases resulting from irrigation depend mostly on the kind of soil, particularly its mois-ture conditions. In the definite vegetation season and in the actual soil conditions the effects of irrigation of cereals varried, and they correlate significantly with the rainfall at growth stage when the requirement of moisture is critical. The problems of irrigation of cereals in Poland should be considered in two aspects: 1. Irrigation of cereals grown on medium and light soils should be consid-ered as interventional, so as to prevent yield decreases caused by drought, and to assure stable crops in the Polish transitory climate condition. That measure can lead to average yield increases: absolute of 0,50–1,00 t.ha-1, relative of 10–30% and unitary of 5–10 kg.ha-1.mm-1. This might not encourage farmers to include cereals in their crop rotation on fields equipped with irrigation systems but cere-als should take a part in an equipped with irrigation systems fields meant for other plants. Irrigated should be the bread varieties of wheat and then malt bar-ley. 2. Irrigation of cereal plants grown on very light ...
On the basis of research done in the Department and literature data, indicesof optimal precipitation and water needs of selected crops (cereals, root plantsand papilionaceae) have been determined. It was found that both insufficient andexcessive precipitation affected yield adversely. It caused the following decreasesin yields: cereals 2-27 and 3-21%, potato 4-45 and 3-30%, sugar beetroot 2-43and 14-19%, fodder beet 16-73 and 8-28%, legumes 5-42 and 21-40%, and papilionaceae3-34%, respectively.Productivity of 1 mm water from precipitation was higher compared withproductivity induced by sprinkling. The calculated index of productivity for waterfrom sprinkling relative to water from precipitation was in the range 40-90%.Sprinkling increased the yield of winter wheat and spring barley by 20%,spring wheat by 25%, potato 47 and 55%, and sugar beet 10-40%. ...
