Evaluation of Asparagus species and comparison between sexes in A. officinalis cultivars for resistance to stem blight

Abstract

Nine taxa of Asparagus species and 34 A. officinalis L. cultivars and lines were evaluated for resistance to stem blight (Phomopsis asparagi S.) under controlled environmental conditions. The plants were inoculated by the vinyl tube and cotton inoculation method (VC inoculation method). Disease susceptivity assessments, based on the percentage of infected plants, were made 4 weeks after inoculation. There were differences in disease resistance among the Asparagus species. A. densiflorus, A. virgatus, A. asparagoides, and A. macowanii were highly resistant. Although none of the cultivars and lines of A. officinalis were completely resistant, there were significant differences in disease susceptibility among them. In addition, the disease incidence in both sexes of A. officinalis cultivars inoculated as above and under a natural environment revealed that there were no significant differences in percentages of the infected stems between male and female plants of A. officinalis cultivars.