Epidemics of the splash-dispersed pathogenic fungus Diaporthe adunca on its host, the perennial herb Plantago lanceolata, were followed during two consecutive years in transects at roadsides in the Netherlands. Epidemics of D. adunca were also studied on clones of a susceptible and a partially resistant genotype of P. lanceolata grown either in a pure stand or in a 1:1 mixture in small plots in the garden. The epidemics in the natural and experimental populations could be adequately described by logistic and Gompertz models, but large differences were found in final disease levels and relative growth rates. The effect of partial resistance on the epidemic in the mixture was less than in a pure stand, probably due to the provision of inoculum from the highly diseased susceptible genotype to the partially resistant genotype. In the garden focal and wind-direction effects were seen. In the natural populations the epidemics developed from numerous primary infected scapes making foci and wind-directions effects less conspicuous. [KEYWORDS: Soybean stem canker; phaseolorum var caulivora; phomopsis-subordinaria; fungal pathogens; leaf rust; communities;cultivar; spread; inoculum; mixtures]
Original languageEnglish
JournalPlant Pathology
Journal publication date1996

ID: 46350