ISSN:
1573-8469
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Studies were made on the leaf-inhabiting fungus flora of two plots of flowering sugarbeet. Flowers were removed from plants of one plot as they appeared. Changes in the numbers of micro-organisms on leaves were recorded by leaf washing and leaf homogenization techniques, and were found to follow closely the changes in numbers of pollen grains seen on cleared leaf discs. The main colonizers, grouped into pink yeasts, white yeasts,Cladosporium spp. andAureobasidium pullulans, were all influenced by the natural presence of pollen and reached high numbers on leaves in the plot bearing flowers. Rainfall was not found to influence numbers of pollen grains or micro-organisms greatly, but high temperature led to isolation of smaller numbers of pink and white yeasts. Recovery of populations was swift after hot weather, and may be linked with the high contamination of fieldcollected sugarbeet pollen by components of the microflora. The spectrum of fungi growing from washed leaf discs differed qualitatively from assessments made by washing and homogenization. Rye pollen stimulatesPhoma betae to aggressive infection of sugarbeet leaves on which, due to the prevention of a natural pollen deposit, the development of the leaf microflora is meagre. Sugarbeet plants in both plots were inoculated with conidia ofP. betae with or without added rye pollen. The presence of a dense microflora, associated with a high natural pollen deposit, reduced the incidence of aggressive infection normally stimulated by the addition of rye pollen to inoculum.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01980472
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