Stärke und Malto-Oligosaccharide in Möhrensorten aus ökologischer Züchtung

Until now starch and its metabolites malto-oligosaccharides have been overlooked as potentially important constituents of carbohydrates in carrots. A comparison of the organically bred cultivars Rodelika and Robila with the hybrid cultivars Maestro F1 and Starca F1 revealed that the content of malto-oligosaccharides in the organic cultivars (126 and 191 mg g-1 dry matter, respectively) surpassed the content in the two hybrid cultivars (86 and 89 mg g-1 dry matter, respectively), although the starch content was similar in all cultivars (between 50 and 70 mg g-1 dry matter). There were also cultivar differences in the pattern of glucose, fructose, and sucrose, however, the total amount of water-soluble carbohydrates (between 550 and 600 mg g-1 dry matter) was similar in each cultivar. Relatively high contents of starch and malto-oligosaccharides in carrot cultivars may be a key factor for their storage potential and quality

Qualität und Ertrag von Öko-Zwiebeln: Vergleich von Pflanzung und Direktsaat

Yield and quality (bulb size, sugar content and composition, pungency, initial sprout growth) of early and late transplanted and directly sown onions (cv. Sturon) were compared in field experiments (2009-2011) at different intensities of weeding (weed-free or mechanical weed control only). Early transplanting (weed-free) resulted in the highest yield and best quality performance, whereas late transplanting combined with mechanical weed control only (including harrowing weeds before transplanting onions) resulted in medium yield and quality, however, at a relatively low work-input. It is suggested that infection by powdery mildew was the key limiting factor in the development of yield and quality in late-transplanted and directly-sown onions

Züchterische Verbesserung der sensorischen Qualität der Pastinake (Pastinaca sativa L.) im Praxisbetrieb

Parsnip (Pastinaca sativa L.) is one of the few cultivated plants domesticated in Europe. The crop is underutilised and the number of available varieties is small in Central Europe. On-farm management of genetic resources can be an important means to increase infraspecific diversity, and to improve the quality of crops. In the present experiment quality-improvement by progeny selection on-farm was investigated. In a first step parsnips were selected for organoleptic quality by a technique that allows to harvest seeds from the plant tested. In a second step, progenies of positive- and negative-selected plants were compared with the original population. The experiment was carried out with the varieties Aromata (2006) and White King (2008) in biodynamic management. Organoleptic quality was determined according to a key developed for parsnip. Sugar contents were determined. Organoleptic selection significantly improved sweetness and flavour and can be recommended. However, selection was not efficient to improve texture