Understanding Botrytis Blight of Gladiolus: Temperature and Inoculum Concentration Effects

Gladiolus is a popular ornamental crop that is often affected by various fungal diseases, including Botrytis blight. This disease is caused by the opportunistic fungus Fusarium oxysporum f.sp. gladioli, which infects aging, damaged, or necrotic plant tissues before invading healthy tissues.

Recent studies have shown significant temperature and inoculum concentration effects on the incidence of Botrytis blight in gladiolus. Higher temperatures and higher inoculum concentrations were found to result in a higher disease incidence. This highlights the importance of manipulating these parameters to influence the time course of an assay.

In addition, significant corm cleaning effects were observed. Cleaning and disinfecting the corm was found to increase the infection level significantly. However, further tests showed that corm cleaning is not advised, as it may damage the corm and lead to secondary infections.

Interestingly, no significant effect of corm size on the level of Fusarium infection was detected. This suggests that the susceptibility of gladiolus plants to Botrytis blight is independent of their corm size.

The study also found a significant cultivar effect, with different cultivars exhibiting varying levels of Fusarium resistance. No information about the effects of corm origin, corm size, corm cleaning, temperature, or inoculum concentration on the level of Fusarium infection was known prior to this study.

For values for cultivation and use purposes (VCU), more information is needed about these conditions. The resistance level of gladiolus cultivars can be determined by calculating the relative length (RL) of the shoots six to eight weeks after planting.

Botrytis blight, caused by Fusarium oxysporum f.sp. gladioli, is a significant problem for gladiolus cultivation and breeding. Resistant cultivars are highly desirable, and partial resistance has been found within the commercial gladiolus assortment. Further research is needed to understand the mechanisms of Botrytis blight infection and to develop effective management strategies.

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Botrytis blight of gladiolus