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TECHNICAL MANUAL
Potato late blight
W. Pérez � G. Forbes
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Potato late blight
© International Potato Center (CIP), 2010
ISBN 978-92-9060-391-7
CIP publications contribute important development information to the public arena.
Readers are encouraged to quote or reproduce material from them in their own
publications. As copyright holder CIP requests acknowledgement, and a copy of the
publication where the citation or material appears. Please send a copy to the
Communication and Public Awareness Department at the address below.
International Potato Center
P.O. Box 1558, Lima 12, Peru
cip@cgiar.org � www.cipotato.org
Cover picture: Ricardo Orrego
Produced by the CIP Communication and Public Awareness Department (CPAD)
Production Coordinator
Cecilia Lafosse
Design and Layout
Elena Taipe and contributors from Graphic Arts
Printed by Tarea Asociación Gráfica Educativa
Press run: 300
June 2010
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Content
Preface 5
Introduction 7
The pathogen 9
The disease 16
Management of late blight 19
Evaluation of late blight resistance 28
Literature 32
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Preface
The development of new technologies has given specialists a better understanding of
the biology of
Phytophthora infestans (Mont.) de Bary. However, much of this information is
presented piecemeal in specific publications that at times are difficult to understand. Inte-
grating all the new information can be even more difficult. This guide is an attempt to
present some of the new information in a summarized form that gives a broad view of the
problem. The CIP (International Potato Center) Project for Integrated Management of Late
Blight has developed a wide variety of training activities for professionals, technicians and
community leaders, as well as participatory research programs using the Farmer Field School
methodology to facilitate knowledge transfer. Furthermore, integrated management strate-
gies have been developed together with national researchers and rural development institu-
tions, considering agro-ecosystem care, farmer and environmental health, all of which are
particularly affected by inappropriate and inefficient use of fungicides.
We hope this guide will be useful for researchers, teachers, students, technicians and
farmers interested in this topic. Chapters on the pathogen, the disease and integrated man-
agement attempt to cover as much information as possible. For this reason, special care has
been taken in analyzing some of the specialized and recent bibliography in order to present
the information in a didactic and objective way. The chapter on evaluation of disease resis-
tance has been laid out based on specialists’ experience and aims to be a useful guide for
those who need to evaluate resistance of new varieties or evaluate new control strategies.
The authors
“He who loves practice without theory is like the sailor who boards ship without a rudder and
compass and never knows where he may cast. “
Leonardo da Vinci
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