WINTER-WHEAT GRAIN YIELDS AND TECHNOLOGIC AL QUALITY AT DIFFERENT SOIL-MANAGEMENT IN SUGAR-BEET GROWING REGION

The results of long-term research in the field of soil management enab led to present conclusions in such a sense that cereals well bear the compacted soil and respond completely positively to the lower depth of cultivation. Authors like Rod, Pesek (1973), Hruby (1989) were devote d to the problems of research of the yield response of winter wheat cu ltivars to different ways of soil cultivation. The aim of the study wa s to evaluate the response of selected cultivars of winter wheat (Danu bia, Zdar and Viginta) to the yield formation when using different tec hnological procedures of chernozem cultivation. Field trials were esta blished in sugar beet production region at the site at Ivanovice na Ha ne in the harvest years 1989 to 1991. Trials were performed in warm re gion with average sum of precipitation 549.8 mm and average temperatur e of 8.5 degrees C (Tab. I). Variants of soil cultivation were as foll ows: I. medium-deep tillage (by three-furrow plough with skim coulter) to the depth of 0.18 to 0.22 m; II. soil cultivation by rotary tools (PH 200) to the depth of 0.20 m; III. soil cultivation by disc tools ( DPN 180) to the depth of 0.10 to 0.15 m. Soil was cultivated after ski mming and winter fertilizing N - 70, P - 15, K - 66 kg, i.e. of pure n utrients per 1 hectare. The grain seeding was carried out in rows of 1 2.5 cm with subsequent harrowing by seed harrow. Grain yields (t.ha(-1 )), thousand-kernel weight - TKW (g), bulk weight - OH (g/l) and propo rtion of grain above sieves 2.5 and 2.2 (%) including minus mesh mater ial were evaluated the trial. Results showed that the total average yi elds of grain bf the above-mentioned cultivars (Tab. II in) soil culti vation by rotary (variant II) and disc tools (variant III) were fluctu ating at the same level. Statistically significantly lowest grain yiel ds were recorded in traditional soil cultivation - medium-deep tillage (minimal significant difference DT0.01 = 0.151). The highest grain yi eld for the studied three-year experimental period was reached by the Viginta cultivar (7.06 t.ha(-1)). A different response of cultivars to different intensity of soil cultivation was recorded in this connecti on. The Danubia cultivar reached the highest grain yield in the varian t III (soil cultivation by disc tools), in the Viginta cultivar the di fferences between variants II and III (soil cultivation by rotary and disc tools) were minimum in the grain yields (on average only 0.07 t.h a(-1)), in the Zdar cultivar the highest grain yields were recorded in rotary soil cultivation. It is evident in view of this that the grain yields obtained in variant I (medium-deep tillage) were the lowest in all three variants (Tab. III). In thousand-kernel weight (TKW), in si milar way as in other studied indicators of the grain quality (bulk de nsity and proportion of grains above sieves 2.5 and 2.2 mm), solely st atistically effect of the year was recorded.