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To investigate the biology and virulence of the rose black spot fungus diplocarpon rosae leading to improved control. - HH1750THN

Description
The main objective of this project is to improve the management and control of rose balckspot by providing a better understanding of the virulence and epidemiology of pathotypes of Diplocarpon rosae and to determine the number of pathotypes of Diplocarpon rosae in the UK in order to improve disease management and control and to thereby reduce pesticide use on roses by both growers and consumers.

Rose black spot is the most important disease of Rosa spp. world-wide. The crop is of significant economic value to UK horticulture, as exports alone were worth £699,000 in 1997 (MAFF Stats) and is of considerable aesthetic importance to the majority of UK gardeners. At present the disease is controlled by intensive fungicide spraying (up to 40 sprays a year) by both commercial abd amateur growers and the disease limits the production and use of many varieties due to lack of disease resistance. Fungicide resistance is also an ongoing problem (pers.com). Development of resistent varieties is hampered by poor understanding of the number and biology of pathotypes.

This proposal aims to study a wide range of isolates of the fungus from the UK and beyond and to characterise these isolates both for their pathogenicity and genetic diversity. The linking of the genetic diversity using molecular techniques with D. rosae pathotypes has not been previously carried out. Furthermore, studies will be made of fungicide use with particular attention paid to the posibility to fungicide resistence in the pathogen. New fungicides will be investigated for their use in the control of the disease. The results of the work on gentic diversity will be used t characterise pathotypes and inform a breeding programme.

A central theme of the programme will be to ensure that the outputs are practically useful to growers and horticulturalists. Collaboration will occur with the National Rose Society and the Royal Horticultural Society, who have agreed and are keen to participate in the programme.

Application of this research will be of direct benifit to growers, rose breeders and the general public through the design of more effective control strategies and the development of resistant rose genotypes. The results of this programme can be used to produce an integrated crop management plan for controlling blackspot on roses and thus reducing pesticide inputs.
Objective
To improve the management and control of rose blackspot by providing a better understanding of the virulence and epidemiology of pathotypes of Diplocarpon rosae and to determine the number of pathotypes of Diplocarpon rosae in the UK in order to improve disease management and control and to thereby reduce pesticide use on roses by both growers and consumers.
Project Documents
• Final Report : To investigate the biology and virulence of the rose black spot fungus diplocarpon rosae leading to improved control.   (479k)
Time-Scale and Cost
From: 1999

To: 2001

Cost: £148,530
Contractor / Funded Organisations
University - Hertfordshire
Keywords
Breeding              
Crop Diseases              
Farming              
Fungicide use              
Horticulture              
Ornamentals              
Roses              
Fields of Study
Horticulture
Horticulture