THE INVOLVEMENT OF FUSARIUM SPP AND TOXINS IN THE ASPARAGUS REPLANT PROBLEM.

In a pot trial seedling asparagus was exposed to two species and three rates of Fusarium inoculum in virgin soil and soil with a history of asparagus production.
Both soils were evaluated either fumigated with Chloropicrin or non fumigated.

Dry matter production was approximately 50% higher in the virgin soil than the replant soil and in the virgin soil fumigation with chloropicrin resulted in bigger plants.
The suppression of asparagus seedlings in the replant soil compared with virgin soil was not reduced by fumigating the soil and therefore could be attributed to phytotoxic material in the replant soil rather than soilborne pathogens.
In both replant and virgin soils oatseed Fusarium inoculum increased the numbers of Fusarium lesions on the asparagus seedling roots and reduced the seedling growth more than conidial suspensions.
Both types of inoculum had increased effect at the higher rate.
Root lesion scores were as useful as plant dry weights for indicating suppression of asparagus seedlings grown with different rates or forms of Fusarium inoculum.
Crown rot scores were not as sensitive as either root lesion scores or shoot and root dry weights to the suppression caused by either inoculum form or the phytotoxic material in replant soil.

VIII International Asparagus Symposium

P.E. Schofield, M.A. Nichols, P.G. Long

https://doi.org/10.17660/ActaHortic.1996.415.44