43. Gartenbauwissenschaftliche Tagung - (DGG) und des

182
Gemüsebau
Effect of N-specification and mycorrhiza inoculation on growth and
composition of Chinese chive
H. Perner 1 , D. Schwarz², A. Krumbein² und E. George 1,2
1
Department of Plant Nutrition, Humboldt University of Berlin, 10115 Berlin, Germany
²Institute of Vegetable and Ornamental Crops, Department of Plant Nutrition,
14979 Großbeeren, Germany.
perner@igzev.de
Introduction
Allium species are grown for their health related and flavor compounds. The compounds are
influenced by sulfur and nitrogen supply. Most soils have sufficient sulfur, but high nitrate
fertilization may decrease plant sulfate uptake. Allium plants can be highly dependent on mycorrhizal
colonisation for satisfactory growth. These relations were tested on Chinese chive
[Allium tuberosum Rottler ex Sprengel]. Three different ratios of ammonium nitrate supply in
combination with AM fungi were tested in terms of growth, nutrient composition, and plant
health related organo sulfur compounds, measured indirectly as pyruvic acid.
Material and Methods
The experiment was carried out in a growth chamber for a period of 3 months, using Perlite as
a substrate with application of a third-strength modified Hoagland solution. Nitrogen was
provided at an ammonium nitrate (NH4:NO3) ratio of 95:5, 50:50, or 5:95. The substrate was
inoculated with a commercial inoculum (AM), (TerraVital Hortimix, Plantworks Ltd., UK).
Non-mycorrhizal (NAM) treatments were supplied with autoclaved inoculum and AM free
filtrate. Each treatment had four replicates. Mycorrhizal colonisation of roots was determined.
Results and Discussion
Inoculation resulted in colonization rates of 43% of total root length for the highest nitrate
supply, decreasing with increasing ammonium supply. Mycorrhizal colonization increased
shoot S-concentrations, but did not significantly increase shoot dry weight, shoot N-, P-, NO3 -
-concentrations, and pyruvic acid concentration. An NH4:NO3 ratio of 95:5 strongly reduced
plant dry weight. In contrast, the plants grown with an NH4:NO3 ratio of 50:50 had similar
shoot dry weight and increased N- and pyruvic acid concentrations as with an NH4:NO3 ratio
of 5:95. Therefore, we conclude that the supply of an NH4:NO3 ratio of 50:50 is preferential
for Chinese chive to produce high contents of health related organo sulfur compounds.
BHGL – Tagungsband 24/2006