Resistenzeigenschaften im Gersten- und Weizensortiment Gatersleben 7. Prüfung der Frostresistenz von Wintergersten im künstlichen Gefrierversuch

Zusammenfassung Von den Faktoren, die zur Winterfestigkeit der Gersten beitragen, wird die Frostresistenz untersucht. Dazu wird ein Verfahren des künstlichen Gefrierens im Kältegewächshaus ausführlich beschrieben.Mit Hilfe dieses Verfahrens wurden aus dem Material des Gaterslebener Wintergerstensortiments bisher 367 Zucht- und Landsorten untersucht. Nach Vergleich mit fünf aus früheren Untersuchungen zur Verfügung stehenden Standardsorten ließen sich diese Sorten in entsprechende Resistenzgruppen einordnen. Die Sorten mit guter Frostresistenz sind Albert (Frankreich), Almerfelder, Dominator, Hellmann und Teilhaber, Schwarze Wintergerste (Deutschland), Kostek, Kujawiak, lski II (Polen), Mozdokskij Mestnij, Odesskij 17 (Sowjetunion) und eine Herkunft vom Peloponnes. Der Verlauf ihrer Frostresistenz während des Winters wird im einzelnen charakterisiert. Die 103 Sorten mit mittlerer Frostresistenz sind einzeln aufgeführt (Tabelle 4).Die Möglichkeiten dieses Verfahrens für eine umfassende Beurteilung der Frostresistenz werden diskutiert, ebenso das Problem der Züchtung winterfesterer Gersten.

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Summary The frost-hardiness of barley, one of the several factors causing winter-hardiness, has been studied by artificial freezing in a cooled greenhouse. The method is described in detail.Out of the Gatersleben collection 367 varieties and land-races of winter barley were tested. This material was grouped, in comparison to standard varieties, into corresponding classes of frost-resistance according to the degree of plant injury. Varieties with high frost-resistance are Albert (France), Almerfelder, Dominator, Hellmann und Teilhaber, Schwarze Wintergerste (Germany), Kostek, Kujawiak, lski II (Poland), Mozdokskij Mestnij, Odesskij 17 (Sowjet-Union) and one land-race from Peloponnesus. Their reaction to frost-resistance during the winter is described in detail. Further 103 varieties, listed in table 4, showed moderate resistance.Finally the possibilities are discussed, given by this method for a comprehensive estimation of frost-resistance, as well as the problem of breeding winter barley varieties with higher frost resistance.

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