Preservation of uredospores of puccinia melanocephala, the causal agent of sugarcane rust

Document Type

Article

Publication Date

1-1-2007

Abstract

The seasonality in the appearance of sugarcane rust makes it difficult to obtain in any season of year, adequate quantities uredospores for artificial inoculations in a breeding program. This research aimed to develop a long-term storage methodology to preserve uredospores of Puccicinia melanocephala to keep their viability and infectivity. Uredospores were collect using a vacuum pump from naturally rusted leaves. Part of these uredospores was dehydrated in silica gel or lyophilized and the other part was not dehydrated. Then they were all stored at different temperatures (room temperature, 5°C, -20°C and -80°C). Subsequently, uredospores viability was periodically evaluated using the water-agar method. After the fourth month, the infectivity was also evaluated through inoculations in leaves of the sugarcane susceptible variety SP70-1143 following disease evaluation. Regardless of the dehydration treatment used, uredospores stored at room temperature and at 5°C were viable for the maximum periods of 1 and 2 months, respectively. The best results were obtained with the silica gel dehydration treatment followed by storage at -20°C or -80°C. Even after one year of storage, these uredospores were able to cause rust in inoculated plants at levels of severity which are adequate to start screening tests for sugarcane resistance to rust.

Publication Source (Journal or Book title)

Summa Phytopathologica

First Page

152

Last Page

156

This document is currently not available here.

Share

COinS