Sorghum and Millets Diseases: A Second World Review

384 Pages·9.114 MB·English

by  De Milliano W.A.J., Frederiksen R.A., Bengston G.D. (Ed.)

Abstract
Citation: de Milliano, W.A.J., Frederiksen, R.A., and Bengston, G.D. (eds,). 1992. Sorghum and millets
diseases: a second world review. (In En. Summaries in En, Fr, Es.) Patancheru, A.P. 502 324. India:
International Crops Research Institute for the Semi-Arid Tropics. 378 pp. 46 ill. ISBN 92-9666-201-8.
Order code: BOE 017.
This book is the product of an international workshop held at Harare, Zimbabwe, in Mar 1988.
Progress made on sorghum diseases since the first global workshop held in India in 1978 is reviewed;
research needs and goals for the next decade are identified; and the strengthening of working rela
tionships among pathologists studying sorghum and millets diseases discussed. Also included are
recommendations made by workshop participants and reports on group discussions.
Resumen
Enfermedades de sorgo y de mijo—Segunda global. Este libro es la de los trabajos
presentados en el congreso llevado a cabo in Harare, Zimbabwe (Marzo 1988). Contiene una
de los progresos alcanzados sobre las enfermedades del sorgo desde el primer congreso realizado en
la India (1978), como tambien la de las necesidades y objetivos de a ser
alcanzados en la y l a de posibles refuerzos en l a e n t re los
que investigan las enfermedades del sorgo y el mijo. Tambien incluye las recomendaciones
dadas por los participantes del congreso y los reportes de los grupos de trabajo.
S o r g h um a nd M i l l e ts D i s e a s es
A S e c o nd W o r ld R e v i ew
Edited by
W.A.J. de Milliano,
R.A. Frederiksen,
and
G.D. Bengston
ICRISAT
International Crops Research Institute for the Semi-Arid Tropics
Patancheru, Andhra Pradesh 502 324, India
1992
Workshop Sponsors
INTSORMIL SADCC/ICRISAT ICRISAT
USAID Title XII Sorghum and Millets International Crops
Collaborative Research Improvement Research Institute
Support Program on Program for the
Sorghum and Semi-Arid
Pearl Millet Tropics
The International Crops Research Institute for the Semi-Arid Tropics is a nonprofit, scientific, research and training
institute receiving support from donors through the Consultative Group on International Agricultural Research.
Donors to ICRISAT include governments and agencies of Australia, Belgium, Canada, China, Finland, France,
Germany, India, Italy, Japan, Korea, Mexico, Netherlands, Nigeria, Norway, Sweden, Switzerland, United King
dom, United States of America, and the following international and private organizations: African Development
Bank, Agricultural University of Wageningen, Asian Development Bank, Deutsche Gesellschaft fur Technische
Zusammenarbeit (GTZ), International Board for Plant Genetic Resources, International Development Research
Centre, International Fertilizer Development Center, International Fund for Agricultural Development, Interna
tional Fund for Agricultural Research, The European Economic Community, The Opec Fund for International
Development, The Rockefeller Foundation, The World Bank, United Nations Development Programme, Univer
sity of Arkansas, University of Georgia, University of Hamburg, and University of Hohenheim. Information and
conclusions in this publication do not necessarily reflect the position of the aforementioned governments, agen
cies, and international and private organizations.
The opinions in this publication are those of the authors and not necessarily those of ICRISAT. The designations
employed and the presentation of the material in this publication do not imply the expression of any opinion
whatsoever on the part of ICRISAT concerning the legal status of any country, territory, city, or area, or of its
authorities, or concerning the delimitation of its frontiers or boundaries. Where trade names are used this does not
constitute endorsement of or discrimination against any product by the Institute.
ISBN 92-9066-201-8
Contents
Preface V
Part 1: Regional and Country Reports (Sorghum)
Sorghum and Pearl Millet Pathology in Zimbabwe E. Mtisi 3-7
Sorghum Diseases in Southern Africa W.A.J. de Milliano 9-19
Sorghum Diseases in Eastern Africa Mengistu Hulluka and J.P.E. Esele 21-24
Sorghum Diseases in Western Africa M.D. Thomas 25-29
Sorghum and Sorghum Diseases in Japan Takashi Kimigafukuro 31-34
Diseases of Sorghum in the Philippines N.G. Tangonan and 35-40
S.C. Dalmacio
Sorghum Diseases in Thailand T. Boon-Long 41-43
Sorghum Diseases in India: Knowledge and K.H. Anahosur 45-56
Research Needs
Sorghum Diseases in Brazil C.R. Casela, A.S. Ferreira, 57-62
and R.E. Schaffert
Sorghum Diseases in South America E. Teyssandier 63-66
Sorghum Diseases in Central America and G.C Wall and D.H. Meckenstock 67-73
the Caribbean Basin
Sorghum Diseases in Mexico J. Narro, V.A. Betancourt, 75-84
and J.I. Aguirre
Sorghum Diseases in North America R.A. Frederiksen and 85-88
R.R. Duncan
A Short Communication on Sorghum Diseases G.A. Forbes 89-91
in Europe
Part 2: Regional and Country Reports (Pearl Milllet)
World Review of Pearl Millet Diseases: Knowledge S.B. King 95-108
and Future Research Needs
Pearl Millet Diseases in Western Africa J. Werder and S.K. Manzo 109-114
Pearl Millet Diseases in Southern Africa W.AJ. de Milliano 115-122
Pearl Millet Diseases in India: Knowledge K.A. Balasubramanian 123-127
and Future Research Needs
Ergot Disease of Pear Millet: Toxicological P.G. Mantle 129-132
Significance and a Mechanism for Disease Escape
Part 3: Current Status of Sorghum Diseases
Bacterial Diseases of Sorghum L.E. Claflin, B.A. Ramundo, 135-151
J.E. Leach, and M. Qhobela
Detection and Identification of Viruses and Virus R.W. Toler and L.M. Giorda 153-159
Diseases of Sorghum
Biotic and Abiotic Factors Associated with Seedling G.N. Odvody 161-166
Diseases of Sorghum
Foliar Diseases of Sorghum G.N. Odvody and PR. Hepperly 167-177
Nematode Pathogens of Sorghum J.L Starr 179-185
Striga (Witchweeds) in Sorghum and Millet: A.T. Obilana and K.V. Ramaiah 187-201
Knowledge and Future Research Needs
Anthracnose of Sorghum M.E.K. Ali and H.L. Warren 203-208
Physiological Races of Colletotrichum graminicola C.R. Casela, A.S. Ferreira, 209-212
in Brazil and R.E. Schaffert
Current Status of Sorghum Downy Mildew Control J. Craig and G.N. Odvody 213-217
Stalk Rots S. Pande and R.I. Karunakar 219-234
Sorghum Ergot R. Bandyopadhyay 235-244
Sorghum Smuts El Hilu Omer and 245-252
R.A. Frederiksen
A Review of Sorghum Grain Mold G.A. Forbes, R. Bandyopadhyay 253-264
and G. Garcia
Cereal Chemistry and Grain Mold Resistance R.D. Waniska, G.A. Forbes, 265-272
R. Bandyopadhyay, R.A.
Frederiksen, and L.W. Rooney
Breeding for Grain Mold Resistance S.Z. Mukuru 273-285
Part 4: Short Communications
Short Communications 289-293
Part 5: Other Topics
Principles and Criteria of Seed Transmission D.C. McGee 297-302
of Sorghum Pathogens
Epidemiology of Sorghum Diseases in Central G.C. Wall, R.A. Frederiksen, 303-317
America: a case study J. Craig, and M.J. Jeger
Using Germplasm from the World Collection D.T. Rosenow 319-324
in Breeding for Disease Resistance
Using the World Germplasm Collection in Breeding S.Z. Mukuru 325-328
for Disease Resistance at ICRISAT
Part 6: Building for the Future
Successful Transfer of ICRISAT Downy Mildew S. Pande and S.D.Singh 331-334
Resistance Screening Technology: an Example
of Transfer of Technology
Recommedations 335-343
Appendix
Discussion 347-370
Preface
Message from SADCC
SADCC is the acronym for the Southern Africa Development Coordination Conference. Presently,
there are nine participating countries: Angola, Botswana, Lesotho, Malawi, Mozambique, Swaziland,
Tanzania, Zambia, and Zimbabwe, (Namibia joined SADCC in 1990).The objective of SADCC is to
strengthen the well-being of their countries and decrease economic dependence on other countries.
There are several important programs in SADCC, agriculture being one. Within agriculture there is a
food security component based in Zimbabwe, and agricultural research is coordinated by Botswana.
Several international centers act as executing agents for programs approved by SADCC. ICRISAT
has one regional program for the improvement of sorghum and millets in Bulawayo and another for
the improvement of groundnuts based at the Chitedze Research Station near Lilongwe, Malawi,
Though the dominant cereal of the SADCC region is maize, sorghum and millets are traditional
and important, particularly in the dry areas. Research to improve these crops is recent compared to
that for maize, wheat, soybeans, and tobacco.
The disease situation is of concern; downy mildew is found widely in the region and leaf diseases
are severe in our nurseries in parts of the area. Grain molds and Striga are also of concern. We now
have a much better idea of which diseases are of priority concern than when we began in 1984, and are
developing strategies to work on them. These will be stated in greater detail in this book.
L.R. House
Executive Director,
SADCC/ICRISAT Regional Sorghum
and Millets Improvement Program,
PO Box 776, Bulawayo, Zimbabwe*
Message from INTSORMIL
Sorghum and millet are vital life-sustaining crops in many parts of the world. The southern African
region is one of the major areas of focus for our collaborative research activities, and many INTSOR-
MIL scientists are involved in projects across many disciplines and countries in the region.
INTSORMIL cooperates with ICRISAT in the long-term degree training program for SADCC
scientists, and many of us enjoy the opportunity of serving as major professors for SADCC graduate
students at our universities in USA. This training program is well underway with 25 SADCC graduate
students currently undertaking MS and PhD degree training in USA. We believe that the long-term
investment in development of the scientific talent in the region will pay handsome dividends in the
future.
I would like to concentrate on two major topics here.
The first concerns fundamentals of the Collaborative Research Support Programs (CRSPs), the
model for collaborative research. The CRSP model is one of several possible means of bringing the
agricultural research capacity of the more developed nations, particularly USA, to bear effectively and
efficiently on the key problems of agriculture in developing nations. It is not or cannot be a short-term
panacea or a long-term solution, but it does hold a great deal of promise as a cost-effective, productive
means of making significant contributions to agricultural development in the developing countries as
a mid-term, interim measure.
v
Despite all the complexities of the CRSPs, bureaucratic and otherwise, the basics are simple and
straightforward. The CRSP model is based on three fundamental assumptions.
1. There are problems that are common in important ways to agriculture in USA and in the develop
ing nations.
2. The assumptions are that collaborative research among agricultural scientists in USA and their
counterparts in the developing nations will be highly complementary. This is to say that the results
of such efforts will be useful in accelerating the agricultural development process in the developing
countries through contributing to the upward shifting of farm-level production functions and the
relaxation of other constraints. It is also to say that it will be complementary in the sense of
providing knowledge, information, and technology useful to the solution of productivity and
adjustment constraints faced by U.S. agriculture.
3.- The model assumes that, from the fixed stock of research resources available to agriculture world-
wide, the scientific output will be greater as a result of such collaborative work. A corollary
assumption of the above is that the expanded output will be mutually beneficial to developing and
developed nations.
My second topic is INTSORMIL: what it is and how it functions. INTSORMIL is the CRSP program
for improvement of sorghum and millet production and utilization in countries where these cereals
are important staple foods. The program is funded jointly by the U.S. Agency for International
Development and by five U.S. universities—Purdue, Texas A&M, Nebraska, Mississippi State, and
Kansas State. Research scientists at these universities develop collaborative research projects with
their counterparts in national agricultural research programs. We believe that strong national research
programs [in less developed countries (LDCs) and the USA alike] are the key to long-term improve
ments in the productivity, marketing, and utilization of these important staple cereals. We also believe
that national research programs (in the LDCs and the USA) can function effectively only with strong
multidisciplinary teams of well-trained and highly motivated research scientists. Our approach to
helping achieve these objectives is through development of mutually beneficial collaborative research
projects between LDC scientists and U.S. scientists. Collaboration involves exchanges of scientists
germplasm, research technology, and information. Enhanced professional development of all collab
orators (from the LDCs or the USA) in the INTSORMIL program will lead to increased efficiency and
productivity of all of our research programs. The collaborative research projects that result will
enhance the lives and economic well-being of all people who depend on sorghum and millet for
sustenance.
In summary, INTSORMIL is a scientist-to-scientist collaborative research program with the goals to
increase the productivity and output of LDC research programs, as well as enhance our research
efforts at U.S. institutions. Its success depends to a very large extent on the development of close
collegial relationships between scientists and we plan to continue developing these relationships.
J.D.Axtell
Professor of Agronomy,
Purdue University, West Lafayette,
IN 47906, USA.
vi
Message from ICRISAT
This book is important for three reasons:
1. The widening food gap in the third world, especially in sub-Saharan Africa, is of great concern to
humanity. The only hope of narrowing this gap is by the use of improved production technology.
Disease-resisting high-yielding genotypes are the kingpins of this technology.
2. This book reflects 10 years of intense activity in sorghum research and we should pause and take
stock of the world situation and plan new strategies for research and development in the war
against diseases and pests.
3. ICRISAT wishes to benefit from the matters discussed in this book to evolve its strategic plan.
Increasing severity of diseases of sorghum and millet, particularly of pearl millet in Africa, is a
matter of great concern. Moreover, a second generation of problems accompanied the introduction of
new technologies based on shorter duration and higher-yielding genotypes; these problems call for
new strategies for removing the stress of diseases and pests. The new problems call for more intensive
and interdisciplinary efforts of research for achieving a breakthrough in the control of diseases for
increasing productivity.
We critically review, in this book, the advances in knowledge and the progress which we have
made in understanding, managing, and reducing the incidence of the diseases and developing ge
notypes resistant to them.
In 1978, grain mold and stalk rots were identified as major disease problems of improved sorghum.
Ten years later, these diseases continue to be at the top of our list. ICRISAT scientists claim that they
have developed sound techniques for identification of resistant material and selected stable sources of
resistance, but this information is only of academic interest unless sorghum breeders make effective
use of this material, incorporating its resistance into agronomically superior sorghums.
Five years ago, an international workshop on stalk rot of sorghum critically reviewed the stalk rot
situation and made specific recommendations. I understand suitable techniques for screening for
disease resistance have been developed, but we have to go a long way to transfer this resistance to
sorghums with agronomically desirable backgrounds.
Sorghum leaf diseases are thought to be more serious in Africa. Some are endemic to certain
regions; in some cases, we do not know if they reduce yields significantly. Without understanding the
mechanisms of disease resistance or the processes and benefits of national and international coopera
tion, success in building up disease resistance is difficult.
Certain diseases, such as ergot and viruses, are affecting the hybrids more than the varieties, and
steps need to be taken to develop resistance against them.
Some pathologists claim that downy mildew of sorghum is no problem. Sources of resistance are
available, as is the knowledge for controlling this disease in sorghum. Judging from the incidence of
this disease in sorghum fields at the Bulawayo facility, I believe we have a long way to go to achieve
success. In pearl millet, downy mildew still remains the severest enemy of the crop. We need to know
more about the mechanism of resistance of this disease. We cannot ignore the fact that there are more
virulent pathotypes in Africa than in India, and that resistance to disease is short-lived and breaks
down quickly. While the breeders are developing newer and newer genotypes resistant to the disease,
the pathogen is evolving more-virulent types. Surprisingly, the wild relatives of pearl millet show no
evidence of resistance to the new pathotypes. There is perhaps a silver lining in the dark cloud,
however, ICRISAT pathologists have found that, even in the susceptible hybrids and cultivars of pearl
millet, an odd plant will show recovery resistance to the pathogen. In the initial stages, these plants
may develop disease under severe disease pressure but later on will outgrow the disease and produce
a normal yield. Some varieties show greater percentages of recovery than others. S.B. King and
J. Craig explain it more authoritatively. This is an important mechanism of survival in cultivars, and
needs to be exploited. I suggest that a team of geneticists and pathologists study this phenomenon
critically, as it seems to hold the key to success in dealing with this disease.
vii
Resistance to ergot in pearl millet, especially in the hybrids, remains elusive. Because of health
hazards associated with ergot, in addition to reductions in yield, adoption of hybrids is restrained.
Innovative strategic and basic research is needed to tackle this disease. Biotechnology may offer an
avenue; the possibility needs examination.
Smut and rust of millet are not so intractable as ergot and downy mildew, but even so, interna
tional cooperation in making use of sources of resistance and evaluating the final products of
breeders' fields is in order. Of course, this is not possible without joint research by pathologists and
breeders, working side by side.
It seems that nematodes are affecting millet in sandy soils of western Africa. I do not know if this
pest is receiving the attention of pathologists, or of the entomologists, or if it is being passed over by
both.
Some disease problems are amplified by nutritional and drought stress. Stalk rot of sorghum and
Striga in sorghum and millet are typical cases. Pathologists, breeders, and plant nutritionists/agrono-
mists working together could be very effective in developing varieties or techniques for managing
Striga and stalk rot in sorghum and millet.
In our research in diseases, we have not made adequate use of biochemistry. I understand er-
gosterol content in the grain is a good indicator of colonization of grain by grain mold fungi; also an
elevated content of 2-4 flavanol in the grain and even in the leaves and stems is a measure of the
ability of a genotype to resist molds. Could such techniques be used routinely in screening for
resistance?
I know that plant pathologists will name large numbers of sorghum and millet diseases in each
ecological zone, but we must develop a practical approach to identify and prioritize the most serious
diseases as targets of research in the next decade. Our major efforts should be the transfer of multiple-
disease resistance to agronomically superior genotypes, or development of a system of disease man-
agement which is practicable and economical to use, even by resource-poor farmers.
The ideas and findings promulgated in this book should lead to development of collaborative
projects between national programs, ICRISAT, INTSORMIL, and institutes in the developed countries
for applied, strategic, and basic research on priority diseases. Active participation and input into the
Cereal Cooperative Research Networks (CCRNs) by pathologists of the national research organiza
tion is essential, as it is these scientists who are in the best position to record and report the incidence
of a disease and the identities of genotypes resistant to it. Screening for disease resistance at hot spots
and use of standard techniques in evaluation is essential, so as to get useful data. ICRISAT has a gene
bank with more than 30 000 accessions in sorghum and 19 000 accessions in pearl millet. It is a rich
source, which needs to be exploited for its sources of resistance to diseases and the other desirable
traits that enable crop improvement.
Our training facilities at ICRISAT Center is another resource for strengthening crop improvement
in many nations of the world, including capability in disease research. I would suggest that the
training constraints in disease management be identified; this information will be useful to ICRISAT.
Special training programs can be organized to meet urgent needs.
Finally, let us not forget that sorghum and millet in the semi-arid tropics are staple foods of the
peasant farmer of limited means, and he needs multiple-disease resistant and high-yielding seed to
grow. He is not interested in pathologists' findings or breeders' claims, but he needs the product of
their joint efforts so that he can produce crops with higher and more consistent yields year after year.
J.S. Kanwar
Deputy Director General Emeritus,
International Crops Research Institute
for the Semi-Arid Tropics (ICRISAT).
Patancheru, A.R 502 324, India.
viii