ISSN:
1871-4528
Keywords:
Solanum spp. L.
;
Sämlinge
;
Knollen
;
Sterilisationsverfahren
;
Stengelstecklinge
;
Sterilkultur
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Description / Table of Contents:
Summary A monoxenic resistance test for routine use was developed to determine the resistance of potato genotypes to the cyst nematodeGlobodera pallida (Stone) Behrens. The basis of the procedure is the aseptic cultivation of the genotypes under test in a nutrient medium in defined conditions. It was possible with it to observe invasion, the development of the nematodes, as well as the dimensions of their feeding cells in the transparent potato roots. Small, quantitative differences, due presumably to the polygenically determined resistance reactions of the genotypes, could be distinguished, and selection for resistance was feasible. For routine trials special procedures were developed using surface sterilisation of potato seed and etiolated sprouts which gave high levels of sterility. The genotypes from seeds could be tested directly, but those from etiolated sprouts had to be prepared by stem cutting. A root system was obtained which correlated with known ratings. Each genotype established from seed and etiolated shoots, developed at different rates, as did their root systems, and no definite timespan could be set before nematode introduction. Growing the cultivars under light before the test resulted in faster root development (Table 2), and a higher nematode infestation than in darkness (Figure 4). The time for nematode inoculation was determined by a rating system based on the location of the perimeter of the root system (Figure 5). In this way physiological factors and the individual growth rate of each genotype were allowed for, with the aim of assessing possibly high levels of nematode infection. At the end of the test the seedling genotypes can be removed from sterile culture and grown on in pots. Where genotypes form minitubers (Table 1) it is possible to proceed early to the next stage in cultivation or to store them trouble-free.
Notes:
Zusammenfassung Zur routinemässigen Resistenzbestimmung von Kartoffelgenotypen gegenüberGlobodera pallida (Stone) Behrens (Pa3) wurde ein monoxenischesin vitro-Verfahren entwickelt, dessen Grundlage die keimfreie Kultivierung der Testgenotypen in einem Nähragarmedium unter definierten Bedingungen war. Dadurch konnte die vollständige Entwicklung der Nematoden sowie die Dimension ihres Nährzellensystems in den transparenten Kartoffelwurzeln kontinuierlich beobachtet werden. Der Test ermöglichte die Selektion resistenter Genotypen anhand geringer quantitativer Unterschiede in der vermutlich polygen-vererbten Resistenzreaktion. Für die Anzucht keimfreier Pflanzen aus Kartoffelsamen und- knollen wurden spezielle Verfahren entwickelt und an mehreren Genotypen geprüft. Die dabei festgestellte Variabilität, insbesondere bei der Wurzelbildung, erforderte für den geeigneten Zeipunkt der Nematodenzugabe die Ausarbeitung eines Wurzelboniturschemas. Die Genotypen konnten nach dem Test in Töpfen weiterkultiviert werden.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02358129
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