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Controlled tile drainage (CTD) practices are a promising tool for improving water balance, water quality and increasing crop yield by raising shallow groundwater level and capillary rise due to drainage flow retardation. We tested the effect of CTD on growth and grain yield of spring barley, at a study site in central Bohemia using vegetation indices from unmanned aerial vehicle (UAV) imagery and Sentinel-2 satellite imagery. Tile drainage flow was slowed by fixed water level control structures that increased soil moisture in the surrounding area according to the terrain slope. Vegetation indices based on red-edge spectral bands in combination with near-infrared and red bands were selected, of which the Normalized Red Edge-Red Index (NRERI) showed the closest relationships with shoot biomass parameters (dry biomass, nitrogen concentration and uptake, nitrogen nutrition index) from point sampling at the tillering stage. The CTD sites showed significantly more biomass using NRERI compared to free tile drainage (FTD) sites. In contrast, in the period prior to the implementation of CTD practices, Sentinel-2 satellite imagery did not demonstrate higher biomass based on NRERI at CTD sites compared to FTD sites. The grain yields of spring barley as determined from the yield map also increased due to CTD (by 0.3 t/ha, i.e., by 4%). The positive impact of CTD on biomass development and grain yield of spring barley was confirmed by the increase in soil moisture at depths of 20, 40 and 60 cm compared to FTD. The largest increase in soil water content of 3.5 vol% due to CTD occurred at the depth of 40 cm, which also had a higher degree of saturation of available water capacity and the occurrence of crop water stress was delayed by 14 days compared to FTD.

Fagus sylvatica Linnaeus (European beech), the ecologically and economically most important broadleaved tree species in the Czech Republic, was strongly reduced in the past. Today there are efforts to increase the proportion of beech to ensure optimal forest tree species composition. When extensively reintroducing beech, it is important to acquire more detailed knowledge of genetic diversity. Thirteen important beech populations in different stands in the territory of the Czech Republic were genotyped using 12 polymorphic nuclear microsatellite markers. The genotypic data from adult trees imply genetic differences between the populations. The estimated genetic diversity expressed as Shannon's information index ranged from 1.73 to 1.92. Thirteen beech populations showed excess homozygotes, as indicated by positive fixation index (F) values (F = 0.005-0.115). The pairwise FST values indicated low genetic differentiation between the 13 Czech beech populations, because they were greater than zero, that means they confirmed the presence of population structuring in Czech European beech. Not significant linear correlations were observed between genetic and geographic distances of the 13 beech populations studied on the basis of microsatellite markers. Twelve microsatellite markers were verified as highly polymorphic and suitable for genotyping of European beech populations.