Resistance to Fusarium oxysporum at Different Developmental Stages of Asiatic Hybrid Lilies

Abstract

<jats:p>Tests for determining resistance to <jats:italic>Fusarium oxysporum</jats:italic> f.sp. <jats:italic>lilii</jats:italic> in different developmental stages of <jats:italic>Lilium</jats:italic> were developed. Under standardized conditions, commercial bulbs, yearling bulbs, scale bulblets, and scales of 16 Asiatic lily cultivars were tested for <jats:italic>Fusarium</jats:italic> resistance. Disease ratings were analyzed statistically using a threshold model for ordered categorical data. For each cultivar in each stage the resistance level was calculated as the disease severity score (DSS). Disease severity score values of cultivars in the four stages were reproducible between experiments, although some variation in cultivars was found. This variation may be attributed to the origin of plant material. Disease severity score values among cultivars in each developmental stage were correlated with the average DSS over all four stages, although some specific cultivar-stage deviations were found. The scale test is recommended for early selection while the scale bulblet test is recommended as a final check.</jats:p>

Molecular Assisted Breeding for Disease Resistance in Lily

“…Breeding for resistance of lily is limited by the relative long juvenile phase, the relative slow propagation of clones and the lack of reliable screening assays during this phase. Screening tests at clonal level have been developed for Fusarium in lily (Straathof and Löffler, 1994a), however, these tests can only be performed several years after crossing and need retesting. Straathof and L öffler (1994b) showed that several genes are involved in the resistance mechanism.…”

Genetic variation in resistance to Fusarium oxysporum f.sp. lilii in the genus Lilium

“…This could be due to differences in developmental stage or to the quality of the bulbs. Differences due to the developmental stage is unlikely as demonstrated by Straathof & Loffler (1994) in Asiatic hybrids. The (inner) quality of the bulbs, however, may be variable.…”

“…Bulb observations were carried out 8 wk (scale bulblets) or 20 wk (yearling bulbs) after planting (Straathof & Loffler, 1994). The resistance levels of genotypes were measured using a disease rating.…”

Transcriptome Sequencing Analysis Provides Insights Into the Response to Fusarium oxysporum in Lilium pumilum

“…lilii is the main pathogen that causes lily basal rot. 2 F. oxysporum can survive for a long time as mycelium in the bulbs or as mycelium, chlamydospore, or sclerotium with diseased residue in the soil. At present, chemical control methods are the main measures to prevent and control lily basal rot.…”

“…4 Although the germplasm resources of Lilium species resistant to F. oxysporum have been used in disease-resistant breeding, the molecular mechanism of disease resistance is rarely reported. In 2013, a cDNA library of the root of F. oxysporuminfested Lilium regale was constructed by suppression subtractive hybridization and 180 sequences homologous to known Transcriptome Sequencing Analysis Provides Insights Into the Response to Fusarium oxysporum in Lilium pumilum 2…”