Annals of Library Science and Documentation
1988, 35(1), 26·33
WORLD LITERATURE ON COWPEA
(VIGNA UNGUICULATA (L.) WALP)
KEN M. C. NWEKE
Department of Library Science
University of Maiduguri
Maiduguri
Nigeria.
World literature on cowpea research covering
mainly the two years, 1981-82 was analysed to
determine the yearly distribution of the literature and the extent of the inclusive retrospective
literature. The nature of the literature and its
form of publication are identified and discussed.
A lso typical journal titles contributing to cowpea research are catalogued and ranked. The
implication
of journal literature in cowpea
research is bigbligbted.
INTRODUCTION
International Grain Legume Information Centre
of the Library and Documentation Centre,
International Institute of Tropical Agriculture,
Ibadan, Nigeria compiles abstracts of world
literature on cowpea published since the year
1900. It has earlier issued three volumes.
Volume I contains 1932 abstracts of papers
published during the period, 1950-1973[11.
Volume II covers the literature published during
1900-1949
and contains 1309 entries [2] .
Volume III contains 1850 abstracts published
during 1974-1980[31.
Entries in the latest volume, Cowpea (Vigna
unguiculata
(L.) Walp): Abstracts
of World
Literature,
volume
IV:
1981-1982, which
covers the literature published during this period
(1981-82) and others published earlier but
omitted from inclusion in the three preceding
volumes constitute the data base for this analysis. It contains 497 abstracts of papers and
covers several aspects of the cowpea literature.
Abstracts in this volume like the preceding
three volumes are of the informative type and
has author and subject indexes.
Cowpeas are of African origin and were
probably domesticated in the millet/sorghum
farming systems of semi-arid West Africa where
most of the crop is now grown [4]. It is an
important food crop widely used since early
times in Africa South of the Sahara, particularly
in West Africa. Its green pods and seeds, pro-
26
vide food for millions of people and feed for
large numbers of livestock. Highly palatable,
it is rich in protein and minerals and relatively
free of metabolites and other toxic compounds.
With toe increasing significance of grain legumes
in agriculture and human nutrition, cowpea
research has been given serious emphasis in the
tropics.
The term cowpea is used to denote the
botanical species Vigna unguiculata and its subspecies as described by Verdcourt[5] whose
recommendations seem to have been widely
accepted. The cultivated subspecies, formerly
treated as separate species are V. unguiculata, V.
sinensis, V. catjang, and V. sesquipedalis. The
cowpea has many common names, those most
frequently encountered in the literature are
southern pea and blackeye pea (in the USA),
lubia or lobia, coupe, frijole, asparagus beans,
yard-long beans and sitao (the last three generally refer to the sub-species sesquipedalis) [6] .
YEAR OF PUBLICATION
Of the 497 items listed in the abstract, 140
items or 28.2 percent of the total literature were
published in 1982, 218 items or 43.9 percent of
the total were published in 1981 while the
rest 139 items or 28.0 percent of the total
were published during the period, 1900-1980
which were omitted from inclusion in the earlier
three volumes (Table 1). This detail is presented
as histogram in figure 1. Larger number of
entries for 1981 than 1982 is interpreted to be
due to the fact that by the time the abstract
was rounded off for printing, many materials
for 1982 were still in press and not yet available
for inclusion. It is most unlikely to be due to
decrease in the growth of the literature during
the two years. The abstract is both current and
retrospective. Although the 1981·82 volume
was issued in January, 1984 it is current in the
sense that it has 1981-82 literature to the
extent of 72.0 percent of the total literature.
Ann Lib Sci Doc
CITATION ANALYSIS OF COWPEA LITERATURE
Table 1
Distribution of the-Cowpea Literature
by Year of Publication
Year
No. of items
139
28.0
1981
218
43.9
1982
140
28.2
Total
497
100.1
Distribution of the Cowpealit_all."..
or of publication
The four volumes (I-IV), therefore, overlap
one another in their coverage of the literature.
For example, Spillman, W.J. published an
article titled, 'The present status of the genetics
problem' in Science (35 : 757-767) in 1912.
A user looking for the abstract of this paper
would normally call for Vol. II: 1900-1949
where it is expected to be listed. However,
this article was omitted from this volume and
was only listed in Vo1.IV: 1981-82. For maximum benefit, therefore, a user searching for an
abstract of a paper published in a particular
year should consult the relevant volume first,
then the later volumes and fmally the previous
volumes. Besides overlapping of the items listed,
an abstract could also appear in volumes covering years preceding its publication as an unpublished document. It is thus best that a
Vol 35 No 1 March 1988
user of the information tool should
the four volumes in a search for an
of a paper that does not appear in the
volume.
NATURE OF COWPEA LITERATURE
1900-1980
Fig.f:
serious
consult
abstract
relevant
Subjectwise distribution of the literature is
shown in Table 2. In the.data base the literature
is classified into eleven categories. The subject
category 'Agronomy' tops the class with 163
items or 32.8 percent of the total literature.
Of these 41 items were published in 1982
and that constitute 29.3 percent of the 1982
publications. 72 items were published in 1981
and 50 items during the period, 1900-1980.
These constitute 33.0 percent and 36.0 percent
of the total literature published in 1981 and
during the period, 1900-1980 respectively.
There were more entries on 'Agronomy' in
1981 (72 items) than in 1982 (41 items).
This does not necessarily mean more publications in 1981 than in 1982 on the subject as
explained earlier. The category
'Agronomy'
included publications on agricultural meterology, climatic influences and crop weather
relations; cropping systems - rotations and intercropping; fertilizers and mineral nutrition;
irrigation, water management and plant-water
relations; soils, soil management and tillage;
seed quality, viability and production; nodulation and nitrogen fixation; and weeds and
weed control.
'Diseases, Pests and Control' follows closely
with 157 items or 31.6 percent of the total
literature. There were 52 items published in
1982 and that is 31.7 percent of total entries
for 1982. Also 78 and 27 items were published
in 1981 and during the period, 1900-1980
respectively. AB in 'Agronomy' there were more
entries in
'Diseases, Pests and Control' in
1981 than in 1982. Although total items in
'Agronomy' (163 items) was more than that in
'Diseases, Pests and Control' (157 items) there
were more entries in·1982 (52 items) and 1981
(78 items) in 'Diseases, Pests and Control'
than entries in 1982 (41 items) and 1981
(72 items) in 'Agronomy'.
Thus in the two years, 1981-1982, of cowpea research greater attention was paid to the
generation of literature on 'Diseases, Pests
and Control' than in 'Agronomy' or any other
category. This is not surprising because diseases
27
NWEKE
Table 2
Subject Distribution
of the Cowpea Literature
1900-1980
Subject
1981
1982
1900-1980 to 1982
No. of
items
Percentage
No. of
items
Percentage
No. of
items
Percentage
No. of
items
Percentage
Agronomy
50
36.0
72
33.0
41
29.3
163
32.8
Diseases, Pests and
Control
27
19.4
78
35.8
52
37.1
157
31.6
Psiology, Growth
and Development
21
15.1
25
11.5
16
11.4
62
12.5
Breeding and Selection
General
16
11.5
25
11.5
8
5.7
49
9.9
10
4.6
8
5.7
28
5.6
Genetics and
Cytogenetics
10
7.2
General (including
Developmental
research)
3
2.2
1
0.5
6
4.3
10
2.0
Processing'
3
2.2
I
1.4
3
2.1
9
1.8
Human Nutrition and
Nutrition Studies
5
3.6
0
0.0
1
0.7
6
1.2
Animal Nutrition
1
0.7
2
0.9
2
1.4
5
1.0
History, Origin and
Evolution
2
1.4
1
0.5
2
1.4
5
1.0
Production and
Marketing
1
0.7
1
0.5
1
0.7
3
0.6
139
100.0
218
100.2
140
99.8
497
100.0
Total
••
and pests are the major obstacles in cowpea
production and storage, hence greater attention
paid to their study and control. 'Agronomy'
topped the class because of retrospective literature, those published during the period, 19001980. There were 50 items published during
the period, 1900-1980, in 'Agronomy' but
27 items published during the same period in
'Diseases, Pests, and Control'. Literature categorized under 'Diseases, Pests and Control'
included physiological diseases as well as those
caused by fungi, bacteria, viruses and nematodes
and their control; insects and storage pests
including rodents and birds and their control.
28
64.4 percent of the literature listed in the
abstracts was generated from the two categories,
'Diseases, Pests and Control' and 'Agronomy'.
The next three categories, 'Physiology, Growth
and Development', 'Breeding and SelectionGeneral', and 'Genetics and Cytogenetics'
accounted for 12.5, 9.9 and 5.6 percents respectively of the literature. In other words,
92.4 percent of the literature listed in the abstract is in the area of 'Diseases, Pests and
Control'; 'Agronomy'; Physiology, Growth and
Developtnent'; 'Breeding and Selection-General';
and 'Genetics and Cytogenetics'. Only 7.7
percent of the total literature is in the area of
Ann Lib Sci uoc
CITATION ANALYSIS OF COWPEA LITERATURE
'General treatment of the subject (including
Developmental Research)'; 'Precessing'; 'Human
Nutrition, and Nutritional Studies'; 'Animal
Nutrition'; 'History, Origin, and Evolution';
and 'Production and Marketing', of cowpea.
Table 4
Non.Journal
Serial Literature by Type
Type
No. of
items
Non-Serial Sources of Cowpea Literature
Of the 497 items listed in the abstract, 32 items
(6.4%) were non-serial literature (Table 3).
These included: books; theses and dissertations;
manuals; pamphlets; and unpublished seminar
papers.
Table 3
Types of Non-Serial Literature Sources
Type of Source
Parts of books
No. of Items
23
Theses and dissertations
4
Manuals (including training and
technical manuals like manual on
cowpea harvester)
3
Pamphlets
1
Unpublished seminar papers
1
Total
Articles in the proceedings of
international workshops
12
Reports (including annual reports,
technical reports and research
reports)
11
Articles in the proceedings of
international conferences
10
Abstracts of unseen materials
(mainly papers presented at or reports of
meetings of professional associations)
8
Articles in the proceedings of
international symposia
7
Articles in the international institute
of tropical Agriculture Research
Highlights
4
Articles in the proceedings of
international colloquia
1
Total
53
32
Non-Journal Serial Sources of Cowpea Literature
serial literature constitutes the rest, 6.4 percent.
Lawani and Seriki[8] have reported that 95
percent of the world literature of rice published
during 1966-1970 and listed in the International
Bibliography of Rice Research, was serial items
while books, non-serial reports and pamphlets
as well as theses and dissertations constituted
only five percent. They have also noted that
comparable figures for the broad field of science
and technology is of the order of 80 percent
periodical publications and 20 percent for
other categories. In general, they concluded,
the narrower a subject is, the lower the proportion of books to articles written on the subject.
The above result for the world literature on
cowpea research substantiate their findings.
465 items (93.6%) of the total was serial
literature of which 412 items (82.9%) were
typical journal literature (see Table 5 and the
Appendix).
Because of the high proportion of journal
literature compared to both non-serial type and
other serial literature, it is discussed under
separate section below. Other serial literature
put together constitute 53 items (10.7%) (Table
4). They included: regular reports; proceedings
of international workshops, conferences, symposia, and colloquia of professional associations
and learned societies; abstracts of unseen items Journal Literature of the Cowpea Research
mainly of papers presented at or reports of the
meetings of professional associations; and The high proportion of journal
literature
articles in International Institute of Tropical (82.9%) to other sources (17.1%) of world
Agriculture Research Highlights.
literature on cowpea research naturally attracts
Thus as stated above 93.6 percent of the special attention. Table 5 and the Appendix
total literature was serial literature while non· show distribution of publications among journal
Vol 35 No 1 March 1988
:29
NWEKE
Table 5
Distribution
of the Cowpea Literature among
Journal Titles
._-----------------...----------o
cCO
c
"'E<:
0"'_
CIl_
.2<:
.- E co
.CIl
'tV,:!
-:;::;
:;._ X
"':::s-'"
0'o
---
•..
o •...... -
z~
23
14
13
12
10
7
6
5
4
3
2
1
-
0-
ze
1
2
1
1
1
7
3
5
7
18
23
106
literature while 106 titles which published
one paper each contributed the remaining
25.7%.
Distribution
of th4I Cowpea literature
~.~~~~·~~~:~~n~~·~~r~~I-t~it~le~--------~
...-
-
Ql
E~
:::s_
Uo
1
3
4
5
6
13
16
21
28
46
69
175
Eni<:
:::S()UJ
U
•.•
_
23
51
64
76
86
135
153
178
206
260
306
412
5.6
12.4
15.5
18.4
20.9
32.8
37.1
43.2
50.0
63.1
74.3
100.0
------------------
titles. A total of 175 titles published papers on
cowpea listed in the abstract. The Appendix
also shows the ranks assigned to each title.
o~o~-----~~~~~~~~~~~~~-~~~~~~~
Phytopathology
was the highest-ranking
o,rnu&alion
of
,,",rift
journal and published 23 papers included in
the abstract. Hortscience and Plant and Soil
(Netherlands) published 14 papers each and
ranked second. These were followed by the
In a study of world literature on rice Lawani
Indian Journal of Agricultural Sciences with and Seriki[8] showed that 50% of all the serial
13 publications and ranked third; Tropical
literature listed in the, International
BiblioAgriculture with 12 publications ranked fourth; graphy of Rice Research, for the years 1966while Indian Phytopathology
published 10 1970 was published by the 50 highest-ranking
papers and had ranked fifth. 23 journal titles titles (out of a total of 958). And that 90%
contributed 2 times each while 106 titles had of all the serial literature was published by
one item each.
about 360 of the highest-ranking serial titles
In the graph (Figure 2) cumulative num- while as many as 600 titles contributed only
bers of journal titles arranged in rank order was 10% of the total serial literature. In general,
plotted against percentage of cumulative num- this type of study shows that a high coverage of
bers of entries published in them. It shows the journal or serial literature of a subject can
that high-ranking titles produced a large pro- be achieved if a few highest-ranking titles are
portion of the total journal literature whereas chosen. The larger the size of the literature
a large number of low-ranking titles produced a under study and longer the period it covered
small proportion of the literature. Thus 50% the more is the literature by a few highestof the total journal literature was produced by ranking titles. 100% coverage would necessitate
28 highest-ranking titles while the rest 147 an extensive search of the serial or journal literalowest-ranking titles produced the other 50% ture. In the case of cowpea, first 69 titles
of the total publications. 69 out of the 175 (Table 5) constitute this highest-ranking titles
journal titles published 74.3~ of the total or the core journal titles.
30
Ann Lib Sci Doc
CITATION ANALYSIS OF COWPEALITERATURE
SUMMARY
The analysis shows that 43.9% of the total
literature was published in 1981,28.2% in 1982
while the rest was retrospective literature,
published during the period, 1900-1980. More
entries for 1981 than 1982 were probably due
to the fact that by the time the abstract was
rounded off for publishing many 1982 materials
were still in press and not available for inclusion.
The literature was classified into eleven categories. 94.4 percent of the total literature was
in four categories while the rest, seven categories
contributed the remaining 7.6 percent. More
literature was generated, in the
category,
'Diseases, Pests and Control', than in any other
in 1981 and 1982.
175 journal titles contributed 82.9 percent
of the total literature. Phytopathology was the
highest-ranking journal and contributed 23 out
of 412 journal articles. 69 journal titles constitute the highest-ranking titles or the core journal
titles. Other serial literature put together contributed 10.7% whereas non-serial literature
contributed the rest, 6.4%. Thus, although
cowpea literature is published in a variety of
formats, journal is by far the most important
format in which it is published. Also large number of journal literature is covered by few
highest-ranking titles while 100% of the literature is covered by a large number of periodical
titles.
Vol 35 No 1 March 1988
REFERENCES
1.
International Grain Legume. Information Centre:
Cowpeas (Vigna unguiculata (L.) WaIp): Abstracts
of World Literature, Vol.' I, 1950-1973,lbadan,
International Institute of Tropical Agricul't'-ure,
1977.343.
2.
International Grain Legume Information Centre:
Cowpeas (Vigna unguiculata (L.) Walp): Abstracts
of World Literature, Vol. II, 1900-1949, Ibadan,
International Institute of Tropical Agriculture,
1979. 194.
3.
International Grain Legume Information Centre:
Cowpeas (Vigna unguiculata (L.) Walp): Abstracts
of World Literature, Vol. III, 1974-1980, Ibadan,
International Institute of Tropical Agriculture,
1981. 435.
4.
Steele, W.M: Cowpeas in Africa, ph.D. thesis,
University of Reading, 1972.258.
5.
Verdcourt, B: Studies in the Leguminosae-papilioniaceae for the flora of tropical East Africa.
Kew Bulletin 1970,24(3),507-509.
6.
Lawani, S M: Grain legume documentation and
information: the contributions of the International Institute of Tropical Agriculture., Quarterly
Bulletin of the International Association of
Agricultural Librarians and Documentalists 1982,
27(2),47-53.
7.
Lawani, S M, Seriki, TAB: Some characteristics
of the world literature on rice. International Rice
Commission Newsletter 1974, 23(1), 1·:15.
31
NWEKE
APPENDIX
Journal Titles Contributing
S.No.
Rank
to the Cowpea Literature
Journal Titles
No. of articles
l.
1
Phytopathology
23
2.
2
Hortscience
14
3.
2
Plant and Soil (Netherlands)
14
4.
3
Indian Journal of Agricultural Sciences
13
5.
4
Tropical Agriculture
12
6.
5
Indian Phytopathology
10
7.
6
Current Science
7
8.
6
Fitopatologia
7
9.
6
Madras Agricultural Journal
7
10.
6
Pesquisa Agropecuria Brasileira (Brazil)
7
11.
6
Plant Disease
7
12.
6
Tropical Grain Legume Bulletin
7
13.
6
Virology
14.
'7
Brasileira (Brazil)
Journal of Agricultural Sciences (Cambridge)
6
15.
7
Journal of Economic Entomology
6
16.
7
Journal of General Virology
6
17.
8
Agronomy Journal
5
18.
8
Annals of Botany (London)
5
19.
8
Dissertation Abstracts International
20.
8
Phytopathologische
Phytopathology
B
5
Zeitschrift: Journal of
5
2l.
8
Plant Physiology (Bethesda)
5
22.
9
Agricultural Research Review (Cairo)
4
23.
9
Biologia Plantarum (Praha)
4
24.
9
Indian Farming
4
25.
9
Insect Science and Applications
4
26.
9
Journal of Nematology
4
27.
9
4
28.
9
Plant Science Letters (Netherlands)
Turrialba
29.
10
Annals of Applied Biology (England)
30.
3l.
10
Annals of the Entomological Society of America
10
Applied and Environmental Microbiology (US)
3
3
3
32
4
Ann Lib Sci Doe
CITATION ANALYSIS OF COWPEA LITERATURE
S.No.
32.
33.
34.
35.
36
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
Rank
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
23 .
106
No. of articles
Journal Titles
Arquivos De Biologia e Technologia (Curitiba)
Australian Journal of Agricultural Research
Cereal Chemistry
Ecole Superieure d' Agriculture de la Suede
Annales (Sweden)
Indian Journal of Agronomy
Indian Journal of Nematology
Journal of Food Science
Journal of the Georgia Entomological Society (US)
Journal of the Indian Society of Soil Science
Journal of Virology
Phillippine Agriculturist (Philippine)
Physiological Plant Pathology (England)
Samaru Journal of Agricultural Research
Tropical Pest Management
Zeitschrift for Pflanzenemahrung
Bodenkunde
3
3
3
3
3
3.
3
3 ..
3
3
3
3
3
3
and
3
2 articles each
Journal titles contributed 1 articles each
Journal titles contributed
Vol 35 No 1 Marcb 1988
33