Epsilon Archive for Student Projects

Abstract

Fusarium root rot, Fusarium solani f. sp. pisi, causes dark lesions and rots on the root- and foot region of peas. This paper provides a literature review, results from methodological development of resistance assessment, and results from resistance assessments. The main questions in this study were:
What method can be used to evaluate resistance against fusarium root rot in peas?
What is the level of resistance in a selection of cultivars?
The literature review aimed to cover the principles of fusarium root rot biology, mechanisms for pea resistance and the interplay between fusarium root rot and pea plant.
The virulence of 16 different isolates of Fusarium solani isolated from pea was assessed by measuring the symptoms on pea plants after inoculation. One of the most virulent isolates originated from a Scanian pea field, and was chosen for the following resistance assessments.
Two inoculation methods were evaluated by using them separately in the virulence assessment; soaking the seeds in spore solution for 24 h, and using the same method with addition of spore solution in the pots 4-5 days after sowing. There were no significant differences between the methods, and to just use the seed soaking method was chosen in the resistance assessments.
In the first resistance assessment, different spore batches were used for different groups of the included 41 accessions. This was due to difficulties with producing enough inoculum. A standard cultivar was incorporated in all accession groups. The standard cultivar provided the information that comparisons between spore batches wasn’t adoptable, but it was possible to see which cultivars that were significantly more or less resistant than the standard cultivar.
In the second resistance assessment the same spore batch was used for all 44 accessions but without replicates. The accessions were ranked according to level of resistance.
Lesion length was found to be a superior measurement of resistance compared to using disease index in both resistance assessments, and is recommended for future high quality phenotyping.
Fourteen accessions were analysed with molecular markers for fusarium root rot resistance. The results of the marker study did not correlate with the results in the resistance assessments.