Use of additives and asparagus cultivars to reduce problems with replanting
There are ongoing problems with replanting asparagus. There have been trials lasting a few years that used asparagus transplants in pots with virgin soil amended with increasing rates of soil from an abandon asparagus field. The transplants were planted in spring and cultivated as usual in a randomized block design. The fern biomass was harvested and weighed in the autumn and the crowns were dug out the following winter and weighed. The objective was to understand the replant phenomenon and find solutions to minimize negative impact. There was a linear correlation between the amount of replant soil (0, 25, 50, 75 and 100%) and decrease in plant biomass. The results show a definite influence of the replant soil which may be due to allelopathic toxins from the asparagus roots and to the Fusarium pathogens. In a different trial, the crown weight was significantly higher after chemical soil sterilization. Therefore this must be caused by the phytopathological part of the replant complexity. There were significantly more fibrous roots in the sterilized and the virgin soil than in the untreated replant soil. Bioassays with 17 cultivars have shown that each cultivar reacted differently with their root growth. There were also significant differences in crown weight after one year. Depending on cultivar the root mass in the replant soil was between 67 and 106% compared to the virgin soil. This study highlights the need to assay cultivars for suitability for replanting.
Aldenhoff, L. (2018). Use of additives and asparagus cultivars to reduce problems with replanting. Acta Hortic. 1223, 213-218
Asparagus officinalis, replant, bioassays, cultivars