Vliv sucha na tvorbu sušiny v jarním ječmeni (Hordeum vulgare L., cv. Amulet, Krona a historická cv. Norimberský).
Authors: V. Hejnák
English / Anglicky:
Production of dry matter of spring barley (Hordeum vulgare L., conv. distichon) was compared in small-plot trials in two present malting varieties, the Czech variety Amulet and the German variety Krona, and the historical variety Nürnberg of 1832 cultivated on medium-heavy fluvisol in the years 2000 and 2001 . The diagram of the experiment included two variants of moisture conditions in small plots for variety: normal - soil moisture during the whole vegetation on the level 60-70 % of maximal water capacity (MWC); and drought - soil moisture on the level 30-35 % MWC induced in half of plots in the period from phase 25.DC to phase 61.DC. Above-ground parts of plants (leaves, stems and spikes) were taken from each variant in selected phases of ontogeny (21.DC, 31.DC, 61.DC, 75.DC, 91.DC) to determine dry matter. Leaf blades had mostly maximal amount of dry matter in the third sampling (phase 61.DC), with subsequent decrease in the time of ripening. Stems reached usually maximal weight of dry matter a little later, during the fourth ripening (phase 75.DC). In the time when dry matter stagnated or was falling in vegetative organs, i. e. in the period of ripening between phases of milk (phase 75.DC) and full (phase 91.DC) ripeness, they showed intensit increase of dry matter by generative organs, i. e. the spikes. The dynamics of this process was higher in new, modem high-yielding varieties of spring barley. The drought stress was statistically significant limiting factor of the plant growth of all three studied varieties and particularly in 2000 it critically reduced the growth of photosynthetic apparatus and prolonging growth of stems in the period of shooting. The stagnation of the size of assimilation apparatus even after end of drought period caused fall of product