Time flies! Six months have passed (surprisingly fast) since the distribution of the first issue of this newsletter. After that issue, we received many requests for copies and seeds from Africa and elsewhere. Our task has become increasingly exciting and, we believe, more useful as we make copies of our newsletter as well as cover crops seeds available to researchers, farmers, extension workers, and other agricultural development workers in Africa and sometimes elsewhere. We distributed 335 hard copies of the first newsletter and more than 700 kg of seed during the first half of 1998. Another highlight was the publication of the first issue of the newsletter on the Internet (see below).
Our wish is that our readers (researchers, extension workers, and rural development workers) have access to electronic mail, if not Internet, which would make our task easier and less expensive.
We thank all the contributors to this newsletter. We hope that all our readers will soon share their experiences in the utilization of cover crops with us in order to allow a real exchange. We also expect your criticisms and suggestions for improvement.
In the last issue, we described a herbaceous legume database called LEXSYS, which is available from the CIEPCA coordinator. Other similar databases that might be of help to cover crops researchers are as follows:
COVERCROPS: A review and database for field users by L. Kiff, B. Pound, and R. Holdsworth. Natural Resources Institute, Chatham, UK. 180 pp.
In this publication, the Natural Resources Institute has reviewed the different functions that cover crops may perform to complement their research on hillside farming systems. They have collected information on 88 cover crop species of which 61 for which the most information is available are contained within an electronic database which uses the software package D-Base.
The data and program files are available on a 3.5" diskette and can be used on any computer running MS-DOS. The database may be searched by a number of key words, including ‘purpose’ for growing the cover crops and several related to ecological adaptability (altitude, rainfall, soil pH, etc.) A very useful part of this database is information on cover crop seed sources. If you do not have D-Base, you can still view the data file (called Ccrops.dbf) using a spread sheet program without the database manipulation allowed by the suite of program files. The copyright page carries the following: "The program is free software: you can distribute it AT NO EXTRA CHARGE and/or modify it. If you modify it you must cause the modified files to carry prominent notices stating that you changed the files and the date of any change. You must distribute the source code with the program".
The copyright page of the document gives guidelines on ordering the document as follows: "No charge is made for single copies of this publication sent to governmental and educational establishments, research institutions, and non-profit-making organizations working in countries eligible for British Government Aid. Free copies cannot normally be addressed to individuals by name but only under their official titles. When ordering, please quote "CRG5". The address: National Resources Institute, Central Avenue, Chatham Maritime, Kent, ME4 4TB, United Kingdom.
We encourage CIEPCA country contacts to order copies for their national research institution.For further information, contact the authors at the following e-mail adresses: <liz.kiff@nri.org> and <barry.pound@nri.org>.
UC Davis database
The University of California at Davis has produced a database of over 40 crop species that can be used as cover crops. Each crop description consists of up to 50 different subject categories. The crops included in the database are adapted to the conditions of central California which is considerably cooler during the winter. This database is on the World Wide Web at: http://www.sarep.ucdavis.edu/sarep/ccrop/search_ccrop.html. Some leguminous cover crops of interest for the African tropics are cowpea (Vigna unguiculata), sunnhemp (Crotalaria juncea), and Sesbania exaltata. Details about each crop occupy approximately 8 pages of text. An example of the summary section on sunnhemp follows:
Warm-season legume
Seldom sets viable seed in California: most seed
imported from Hawaii
Tolerates poor, sandy, droughty soils; requires good
drainage
Native to India and Pakistan
Flowering in August-September
Height
39-117"
Biomass 12,500-14,000 lb/a (11,000 — 12,500 kg/ha)
N content
1.7%
Flowers attract lygus bugs
Planted to moisture in summer, this requires
one subsequent irrigation for 60-day green manure crop in Davis,
California
Sometimes grown as a warm-season cover crop in alternation with
vegetable crops
RABAOC-AFRNET
A concern for adequate
livestock feed, especially during the dry season, led to the development of
a collaborative project between CIRAD-EMVT (Centre de Coopération
Internationale en Recherche Agronomique pour le
Développement-Elevage et Médecine Vétérinaire,
Montpelier, France), CIAT (Centro Internacional de Agricultura Tropical,
Cali, Colombia), and ILRI (International Livestock Research Institute,
formerly ILCA, International Livestock Centre for Africa) to work with NARS
to screen a number of forage species at several sites in West and Central
Africa. The project was called "Réseau de Recherche en Alimentation
du Bétail en Afrique Occidentale et Centrale" (RABAOC) and was a
part of ILRI's African Animal Feed Resources Network (AFRNET). From
1990 to 1994, the collaborators grew potential forage species, among which
were 8 grass, 6 shrub, and 21 herbaceous legume accessions from CIAT, ILCA,
and IDESSA (Institut des Savanes, Côte d’Ivoire). Screening was
carried out in 18 trials in 8 countries (Central African Republic,
Cameroon, Côte d'Ivoire, Ghana, Guinea, Nigeria, Senegal, and Togo).
The results of this research are available on diskette and as CIAT Working
Document No. 145. Information may be available from CIAT or individual
collaborators. The latter may be an appropriate contact for information
about seed availability or performance within the country where they were
tested. Collaborators are listed below along with their affiliation and the
siteof screening.
- Mathieu Bérékoutou/Fernand Koumanda, ANDE, BP 1509 -
Bangui, Central African Republic (site Bossembélé)
- Peter Barnes, ARI-CSIR, P.O. Box 20, Achimota, Ghana (site Pokoase)
- Mamadou Diallo/Lasana Camara, MARA-DNE, BP 559, Conakry, Guinea (site
Boké)
- M. Bodji N'Guessan, CRZ-IDESSA, 01 BP 1152, Bouaké 01,
Côte d'Ivoire (site Bouaké)
- Shirley A. Tarawali, ILRI/IITA, PMB 5320, Ibadan, Nigeria (site Kurmin
Biri)
- Emmanuel Agishi/O.S.Onifade, NAPRI, Nigeria (site Shika)
- Alain Bigot, CIRAD-A.B.T./ Ambroise Diatta, ISRA/CRZ/Kolda, Cultures
Fourragères, BP 53 - CRZ, Kolda, Senegal (site Sare Yoro Bana)
- P.T. Agbemelo, ESA/UB, BP 1515, Lomé, Togo (site Kovié)
- Atisso Defly, CREAT-INZV, BP 27 - Agou, Togo (site Aventonou)
- Jean Kouonmenioc, IRZV, BP 1457, Yaoundé, Cameroon (site
Nkolbisson)
To contact CIAT: Dr Peter Kerridge, CIAT, AA 6713, Cali, Colombia.
(email: <p.kerridge@cgiar.org>)
To contact ILRI: Dr. Shirley Tarawali, ILRI/IITA, PMB 5320, Ibadan,
Nigeria (email: <s.tarawali@cgiar.org>)
Canavalia ensiformis (jackbean) for animal feed in Nigeria
Professor A.B.I. Udedibie works at the Federal
University of Technology in Owerri in southeastern Nigeria. He has been
working for several years on processing Canavalia ensiformis
(jackbean) seed for animal feed. Much of his work was funded by IFS
(International Foundation for Science) and in 1997 he was presented with
the IFS/Danida award for African Agricultural Researchers for his work on
Canavalia. Prof. Udedibie is now looking for funding to introduce
jackbean into the farming systems in Nigeria, as a cover crop/green manure
and animal feed. A research article on the topic by Prof Udedibie is:
"Nutritional evaluation of jackbean (Canavalia ensiformis)
for the Nigeria poultry Industry". 1990. AMBIO volume 19 issue 8 pages 361
-365.
Part of the abstract of that article follows: "Phytochemical studies showed that the raw jackbean seed contains growth-inhibiting substances which can be removed by heat treatment. However, heat treatment alone improved the nutritive value of jackbean for rats up to 20% dietary level but not for broilers or layers, beyond 10% dietary level. Soaking the raw seed in urea solution for a few days, followed by boiling for an hour or so improved nutritive value to the point where a dietary mix containing 20% jackbean was tolerated by layers and a mix of up 30% jackbean by broilers."
Dr. B.O. Esonu also from the Department of Animal Production at the Federal University of Technology in Owerri writes that they have distributed large amounts of Canavalia ensiformis seed to farmers in Plateau State through the Plateau State Agricultural Development Project.
For further information, please contact:
- Professor A.B.I. Udedibie, Department of Animal Production, Federal
University of Technology, P.M.B. 1526, Owerri, Nigeria.
- Dr. B.O. Esonu,
Department of Animal Production, Federal University of Technology, P.M.B.
1526, Owerri, Nigeria.
It is known that some cover crops, under certain circumstances, can limit weed infestations. Little is known, however, of the effect of cover crops on parasitic weeds. Could they be used, for example, as a component of integrated Striga hermonthica control in Africa?
S. hermonthica is a parasitic weed which attacks cereal crops such as sorghum, pearl millet and maize, causing yield losses estimated in the hundreds of millions of dollars every year. The severity of the damage comes from the close interaction between the crop and the parasitic weed. A connection is established between the vascular systems of both plants, allowing S. hermonthica to divert water, minerals, and organic compounds necessary to its development.
No efficient control method against S. hermonthica has been made readily accessible to farmers so far. Nevertheless, an integrated approach including the use of tolerant cultivars, adequate cultural practices, and biological control could help limit the damage. During the last decade, IITA (International Institute of Tropical Agriculture) has developed tolerant maize cultivars whose potential has been demonstrated (Kim 1994). Furthermore, Berner et al. (1995) have proposed a land management approach based on rotation with nitrogen-fixing legumes. Progress has also been made in the development of biological control methods. It has been demonstrated that a few strains of Fusarium have an inhibitory effect on S. hermonthica germination (Abbasher et al. 1996; Ciotola et al. 1996b). Experiments conducted by researchers from Macdonald College, in Canada, in collaboration with researchers from the Institute of Rural Economy, in Mali, have revealed the capacity of a strain of F. oxysporum to decrease S. hermonthica infestation level in the field (Ciotola et al. 1996a). This could lead to the development of an efficient bioherbicide.
Recently, we have developed an interest in the effect of F. oxysporum and organic residues (some of them coming from cover crops) on S. hermonthica infestation. Organic residues could serve as a substrate for F. oxysporum, while increasing soil fertility, thus helping to limit the damage caused by S. hermonthica. It is worth mentioning that on-farm researchers in northern Benin have observed that a fallow of mucuna reduces S. hermonthica infestation level (R. Carsky, 1998, pers. commun.). Will cover crops soon become an inevitable component of the integrated control of parasitic weeds in Africa? A story to be continued ...
References
Abbasher, A.A., Hess, D.E., Sauerborn, J. and Kroschel, J. 1996. pp. 879-887 In: Moreno, M.T. et al. Proc. Sixth Intern. Parasitic Weed Symp., Cordoba, 1996.
Berner, D.K., Kling, J.G. and Singh, B.B. 1995. Plant Dis. 79: 652-660.
Ciotola, M., Diarra, C., Watson, A.K. and Hallett, S.G. 1996a. In: Proc. IX Intern. Symp. on Biological Control of Weeds, Stellenbosh, Afrique du Sud,1996.
Ciotola, M., Hallett, S.G. and Watson, A.K. 1996b. pp. 871-878 In: Moreno, M.T. et al. Proc. VI Intern. Parasitic Weed Symp., Cordoba, Espagne, 1996.
Kim, S.K. 1994. Crop Sci. 34: 900-907.
For more information, please contact:
A. Olivier and A. Létourneau: Département de phytologie, Université Laval, Sainte-Foy (Québec), G1K 7P4, Canada. Alain.Olivier@plg.ulaval.ca,
M. Ciotola and A.K. Watson: Department of Plant Science, Macdonald College, 21111 Lakeshore, Sainte-Anne-de-Bellevue (Québec), H9X 3V9, Canada.
K. Coulibaly, Institut d'économie rurale, B.P. 186, Sikasso, Mali.
Egusi: high protein crop with multiple uses, but neglected and underutilized
(S.R. Vodouhè and L. Capo-Chichi)
Egusi is an important oil/food crop widely consumed in West Africa. It is given the false name of "sesame" in most French-speaking African countries. In spite of its high nutritional value and protein content, good quality oil and providing good soil groundcover, the crop does not benefit from national or international research activity.
Exploratory missions and survey in Benin Republic and Nigeria, reinforced by a literature review, indicated that the crop known as egusi regroups several species of Cucurbitaceae such as Citrullus lanatus, Cucumeropsis sp and Lagenaria siceraria. They consist of various climbing, crawling, trailing, and creeping herbaceous plants.
Citrullus lanatus and Lagenaria siceraria, which are herbaceous annual plants, are effective for weed control, since they can fully cover the soil and are often used for soil fertility restoration or land rehabilitation. In addition, seeds of most cultivated species can have a protein content of 30—40 % and a similar percentage oil content, comparable to groundnut with a protein content of 23—30 %. With good cultural practices and appropriate postharvest techniques, egusi can substantially raise farmers income and soil fertility. Therefore, it is important that the crop be taken into consideration by Plant Genetic Resources programs to avoid genetic erosion.
Preservation of neglected and underutilized crops is one of the major objectives of the International Plant Genetic Resources Institute (IPGRI). Samples of cultivated crops, trees, medicinal plants, and wild relative species are collected and conserved ex or in situ in national and/or international research institutes. To know more about the crop, IPGRI has initiated, in collaboration with national plant genetic resources programs of Benin, Nigeria, and Togo, a survey on the genetic diversity of egusi in the region.
For further information, please contact:
- Dr. Sognon Raymond Vodouhè, IPGRI C/O IITA-BENIN Research Station 08 BP 0932 Cotonou, Benin Tel. (229) 35.01.88 Fax : (229) 35.05.56 E.mail: <R.Vodouhe@cgiar.org>
- Ludovic Capo-Chichi, Consultant 04 BP 1285 Cotonou
— Benin
Tel : (229) 30.46.53
COVER CROPS ADOPTION IN OTHER PARTS OF THE TROPICS
Report from Brazil meeting. Synthesis of what was learned from
southern Brazil
(P. Vissoh)
An international conference on the utilization of legume cover crops by small farmers in the tropics and subtropics was held from 6 to 12 April 1997 in Chapeco, Brazil. Africa was represented and was able to share her experiences on this issue with the other continents. West Africa presented two case studies on the utilization of velvet bean and Stylosanthes.
The velvet bean (Mucuna spp.) and Stylosanthes are the most common legume cover crops in West African small farms. These plants are used either to preserve and/or improve soil fertility (organic matter and nitrogen content of the soil) or to control weeds including Imperata cylindrica, or as fodder crops (Stylosanthes).
In Brazil, several legume species are still being studied on-station. In farmers' fields, the velvet bean is mainly used on steep slopes to control soil erosion and to improve soil fertility. The seeds are often incorporated into animal rations.
When temperatures do not go too far below zero, the velvet bean does not die naturally as is the case in West Africa. Under such circumstances farmers use herbicides or specific machinery to terminate the vegetative cycle of the plant. The mulch obtained softens the soil, preserves moisture, and enhances microbial activity. Through the use of velvet bean, land preparation is reduced from conventional tillage to minimum tillage, and subsequently to zero tillage. Zero tillage makes the use of velvet bean economically profitable.
The sites visited are large farms used for both agriculture and livestock production. Their size ranges from 6.75 to 37 ha. More than 50% of the 9 farms visited are larger or equal to 20 ha and about 80% are over 10 ha. These farms are considered as large-scale farms in West Africa. The crop rotation observed in these farms makes the soil suitable for crop production (maize, onion, tobacco, soybean, and cowpea) and animal production (pigs, poultry, and fish). Each farm has grazing land for sheep and cattle, as well as forestland and a forestation scheme.
Several integrated management options are observed in these farms. For example, they intercrop legumes with other local cover plants in the farming systems, and they combine legumes with chemical fertilizers. Crop production is done in close relation with dairy cow and pig breeding. Similarly, poultry and fish production on the one hand, and pig and fish production on the other hand, are closely related.
Agricultural machinery adapted to various cropping operations was exhibited. Finally, different committees were set up to study and assess the potential and constraints related to the use of legume cover crops. The findings of the committees were reported in the final draft of the conference proceedings, which is in press.
For further information, please contact: P. Vissoh 04 BP 1091 Cotonou; République du Bénin Tél: 300459; Fax: 300637; E-mail: <SG2000b@intnet.bj>
INFORMATION TECHNOLOGY HIGHLIGHTS
CIEPCA newsletter on Internet
The first issue of the CIEPCA newsletter (Feb 1998) is now available on the Web via the MOIST website at http://ppathw3.cals.cornell.edu/mba_project/moist/CIEPCA1.html You can choose various versions of the newsletter from this site depending upon the sophistication of your computer and quality of your phone lines. There is a full graphics pdf version (requiring Adobe Acrobat Reader which is available on the internet) as well as a "text only" version for those whose computers download very slowly. The French version is also available.
MOIST is the Management of Organic Inputs in Soils of the Tropics (MOIST) Group of the Cornell International Institute for Food, Agriculture and Development (CIIFAD). We thank Lucy Fisher for her time spent putting the CIEPCA newsletter on the Internet. It will save us postage to users who have access to the Internet and allow us to post hard copies almost exclusively to colleagues in Africa.
Progress on e-mail connectivity with CIEPCA country contact people
One of the objectives of CIEPCA is to promote communications by e-mail. A needs-assessment questionnaire (UNGANISHA) has been sent to CIEPCA national research programs. Table 1 shows the current status of e-mail connectivity with country contact people:
Table 1: Progress on e-mail connectivity with CIEPCA country contact people
| Pays | Com | e-ma | Ungani | Profor | Cheq | Stat |
| Bénin | Y | Y | CIEPCA/IITA | |||
| Burkina | Y | S | Y | Y | N | |
| Cameroun | ? | N | N | Y | N | |
| Côte d'Ivoire | Y | Y | WARDA(ADRAO) | |||
| Ghana | S | S | Y | Y | Y | P |
| Mali | Y | N | Y | Y | N | |
| Nigeria U | S | N | Y | Y | Y | P |
| Nigeria Z | S | S | Y | Y | Y | P |
| Sénégal | Y | Y | Y | Y | Y | C |
| Togo | N | N | N | Y | N | |
Legend:
Com: computer available
e-ma: access to e-mail
Ungani: UNGANISHA form completed
Profor: proforma invoice sent
Cheq: CIEPCA cheque received
Stat: status
Nigeria U: Nigeria correspondent in Umudike (Southeast)
Nigeria Z: Nigeria correspondent in Zaria (North)Y: yes P: pending
N: no C: connection achieved
S: shared with other people
Out of the 10 country contact people listed, 8 come from national agricultural systems. The contact person in Benin is the Coordinator of CIEPCA, and the one in Cote d'Ivoire is, for the time being, a researcher from WARDA (West Africa Rice Development Association). Of these 8 national correspondents, 1 has already been connected to Internet with the financial support of CIEPCA, 3 have received their cheque from CIEPCA. The case of the 4 correspondents who have not received their cheque needs more assessment.