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Afghanistan Water, Agriculture, and Technology

Transfer (AWATT) Program

Fact Sheet: Forage Cowpea

Dr. Hamdy Oushy

Associate Professor

College of Agricultural, Consumer, and Environmental Sciences

New Mexico State University

Forage and Rangeland Management Specialist, USAID-NMSU/ AWATT

E-Mail: [email protected]

Cell: + (93) 0788-043-397

mailto:[email protected]

AWATT Forage Cowpea Fact Sheet

Afghanistan Water, Agriculture and Technology Transfer Program i

Authority Prepared for USAID/Afghanistan under Cooperative Agreement No. 306-A-00-08-00506

awarded 03 March 2008, entitled Afghanistan Water, Agriculture and Technology Transfer

(AWATT).

This document was completed in partial fulfillment of Clause 2a of the Award Document for

Cooperative Agreement No. 306-A-00-08-00506 awarded 03 March 2008, entitled Afghanistan

Water, Agriculture and Technology Transfer (AWATT). The views expressed and opinions

contained in this report are those of the NMSU AWATT team and are not intended as

statements of policy of USAID.

Prepared by:

NMSU-AWATT Team with CSU, UIUC, and SIUC

Credits The program referred to in this document is based on the NMSU-AWATT Technical Proposal, as

revised, submitted February 4, 2008 in response to USAID Request for Application No. 306-07-02

Disclaimer The opinions expressed in this document are those of the author and are not intended as statements of

policy of USAID or the United States Government.


Afghanistan Water, Agriculture and Technology Transfer Program ii

TABLE OF CONTENTS

Abbreviations and Terms ............................................................................................................................... iii

Forage Cowpea ................................................................................................................................................. 1

Introduction .............................................................................................................................................. 1

Soil Requirements ..................................................................................................................................... 1

Varieties .................................................................................................................................................... 1

Sowing ....................................................................................................................................................... 1

Sowing methods ........................................................................................................................................................ 1

Sowing rate ................................................................................................................................................................ 2

Sowing time ................................................................................................................................................................ 2

Nitrogen Fixation ...................................................................................................................................... 2

Fertilizer .................................................................................................................................................... 2

Irrigation Management ............................................................................................................................. 3

Cutting Management ................................................................................................................................ 3

Forage Production ..................................................................................................................................... 3

Seed Production ........................................................................................................................................ 4

Forage Mixture .......................................................................................................................................... 7

Position of Forage Cowpea in Crop Rotation ............................................................................................ 7

Forage Quality ........................................................................................................................................... 7

Crud Protein ............................................................................................................................................................... 7

Digestibility ................................................................................................................................................................. 7

Forage Preservation .................................................................................................................................. 7

Hay ............................................................................................................................................................................... 7

Silage............................................................................................................................................................................ 8

Acknowledgements ....................................................................................................................................... 11


Afghanistan Water, Agriculture and Technology Transfer Program iii

ABBREVIATIONS AND TERMS

AWATT Afghanistan Water, Agriculture and Technology Transfer

Canal In this and all AWATT documents, the word “canal” refers to either a

secondary or tertiary canal. 1

CSU Colorado State University

jerib Unit of land area approx. 0.2 hectare

karez Usually unlined sloping tunnels in the hills that access aquifers

MAIL Ministry of Agriculture, Irrigation and Livestock

MEW Ministry of Energy and Water

NMSU New Mexico State University

NVDA Nangarhar Valley Development Authority

SIUC Southern Illinois University Carbondale

UIUC University of Illinois at Urbana-Champaign

US United States

USAID United States Agency for International Development

USDA United States Department of Agriculture

1 This distinction is important because the new Afghan Water Law passed last year (2010) gives responsibility for

primary canals (diverted directly from the rivers) to the Ministry of Energy and Water (MEW), and for secondary canals (diverted from the primary canals to villages) and tertiary canals (diverted from the secondary canals for distribution to the farms) to be the responsibility of MAIL, specifically the newly established MAIL Department of Irrigation (DI). Similarly, the term “watercourse” is used interchangeably with the word “canal” in AWATT documents.


Afghanistan Water, Agriculture and Technology Transfer (AWATT) Forage Program 1

FORAGE COWPEA

Common Name: Forage Cowpea Scientific Name: Vigna unguiculata

Local Name: لوبيا علفي

INTRODUCTION

Cowpea (Vigna unguiculata) is a leguminous forage crop. Cowpea (Vigna unguiculata) is a forage

legume, which can be grown in relatively infertile sandy soils with a minimum annual rainfall of

200mm. It is a fast growing, drought resistant crop, which also improves soil fertility by fixing

atmospheric nitrogen. Cowpea forage is usually superior to other forage legumes in terms of

both quantity and quality. Cowpea crop is grown as a green manure and also a cover crop to

increase soil fertility, retain moisture and reduce soil erosion (Koralagama, K. D. N. et al. 2002).

It is suitable for Afghanistan summer environmental conditions. Cowpea performed very well in

Kabul, Herat, and Balkh Provinces in the summer of 2010. It is a fast growing, annual, summer

forage legume. It is an excellent quality crop for fattening both sheep and cattle, and is also

regarded as good feed for milking cows. In a crop rotation program, cowpea can significantly

improve soil nitrogen levels by nitrogen fixation or by incorporation in the soil as a green

manure crop. Cowpea also offers an alternative for grain production. In addition, cowpea is

tolerant to drought and heat.

SOIL REQUIREMENTS

Cowpea does very well in a wide variety of soils from light, sandy soils to well-drained, heavier-

textured soils. Cowpea requires well-drained soils.

VARIETIES

The Cowpea Cream-1 variety, which originated in Egypt, is the main forage summer legume

variety grown, especially in Egypt, and was recently introduced in Afghanistan by Dr. Hamdy

Oushy, AWATT Forage and Rangeland Management Specialist, in May 2010. The first forage

demonstration and seed production sites for cowpea were established at MAIL-Badam Bagh

Agricultural Research Station in Kabul in June 2010 through a collaboration forage program

between the AWATT and ASAP projects.

SOWING

Sowing methods

Cowpea is best sown into a well-prepared and leveled seedbed that has a good depth of

subsoil. The seed should be sown at a depth of 3 to 4 cm into soil. Two sowing methods could

be used: 1) Sowing into plot on 35 cm row spacing with 25 cm plant spacing; 2) sowing into

furrows on 75 cm furrow with spacing of 20 cm between plants.



Sowing rate

Sow cowpea at 10 kg per jerib on plots and 12 kg per jerib on furrows of good quality seed

under irrigation conditions.

Furrows suitable to sow forage cowpea at Dehdadi Agricultural Research Station, Balkh Province in June 2009

(Oushy, 2009); Cowpea, Cream-1 variety, planted on furrows at MAIL-Badam Bagh Agricultural Research Station

in Kabul, in July 2010 (Oushy, 2010).

Sowing time

Cowpea can be sown during the spring and summer seasons. In most Afghan provinces, cowpea

can be sown for forage from April to May. The earlier sowings usually produce the most feed

and the highest number of cuts.

NITROGEN FIXATION

The forage legume cowpea nodulate readily when naturally or artificially inoculated with the

correct strain of rhizobia. The production of nodules depends on the efficiency of inoculation,

soil moisture, soil temperature and soil acidity. Nodulation appears to improve with good soil

moisture and lower soil temperatures. Poor nodulation sometimes occurs with increasing soil

temperature and low soil moisture. When well-nodulated; cowpea can fix around 4 to 28 kg

residual nitrogen per jerib in the soil. Such levels of nitrogen fixation represent the equivalent of

around 10–60 kg urea fertilizer per jerib. The amount of soil nitrogen fixed varies widely, but

the effect on the following cereal crops is usually dramatic.

FERTILIZER

Location, soil type and history of fertilizer application will determine fertilizer needs. It is

preferable to add organic manure to the poor and sandy soil in organic matter. Phosphorus is

the main nutritional requirement and should be applied at soil preparation. Soils with low to

medium levels of phosphorus require 25 to 30 kg Di-Ammonium Phosphate (DAP) per Jerib.

After two weeks from germination, 20 kg of Urea should be applied per Jerib.



IRRIGATION MANAGEMENT

Cowpea plants should be irrigated according to the irrigation sequences. In addition, it requires

9-12 irrigations according to the soil type, soil and air temperatures. Lack of water irrigation

will negatively affect the fresh forage and seed yield.

Flexi Flume irrigation system was used to irrigate forage cowpea, Cream-1 variety from Egypt, at MAIL-Badam

Bagh Agricultural Research Station in July 2010 (Oushy, 2010).

CUTTING MANAGEMENT

Cowpea produces up to three cuts per season. Cutting should be started when plants reach 60

cm heights. The first cut should be implemented after 60-65 days from plantation; then, the

second cut after 45-55 days from the first cut; followed by the third cut after 50 days from the

second cut.

FORAGE PRODUCTION

Cowpea can produce a good yield of high quality dry matter. Forage yield ranges between 5 – 7

tons per jerib in the first cut. Then, it declines to 4 tons per jerib in the second and the third

cuts. In general, the leaf and leaf stalk portion should be considered in determining the feed

availability of the crop.



Forage cowpea field and cowpea plant of Cream-1 variety from Egypt at MAIL-Badam Bagh Agricultural

Research Station, Kabul in July 2010 (Oushy, 2010).

SEED PRODUCTION

In case of seed production, cowpea plants should not be cut for forage at all. In addition, it

should be sown in furrows with good irrigation to assure high seed yield.

Cowpea seed production field of Cream-1 variety from Egypt; cowpea pods are in the maturity stage at MAIL-

Badam Bagh Agricultural Research Station, Kabul in October 2010 (Oushy, 2010).

The seed pods will become dry 4-5 months from plantation. Seed yield ranges between 400 –

500 kg per jerib according to the variety and the production conditions. Harvesting cowpea is

carried out on two picks. The first pick will take place when 70 - 80% of the pods are matured

and dried.



Cowpea seeds were harvested by trained workers in plastic baskets and transferred from the field to the

collective site at MAIL-Badam Bagh Agricultural Research Station, Kabul in October 2010 (Oushy, 2010).

Training extension workers and farmers how and when to harvest the cowpea pods is essential

to ensure high quantity and quality cowpea seed production. At the MAIL-Badam Bagh

Agricultural Research Station, AWATT and ASAP programs have initiated a collaborative

training program for MAIL extension workers, farmers, faculty members, teachers and students

in cowpea seed and forage production.

Trained workers harvested the forage cowpea pods and transferred to the collective seed site at MAIL-Badam

Bagh Agricultural Research Station, Kabul in October 2010 (Oushy, 2010).



Forage cowpea seeds produced at MAIL-Badam Bagh Agricultural Research Station in 2010 (Oushy, 2010).

It is important to know the right time to harvest the first pick of cowpea pods. Sometimes, if

you’ve missed the right time to pick them up, the pods will start shattering and the seeds will

fall down to the soil and be wasted. Therefore, the training of farmers and cowpea seed

producers is very important to produce high seed yield and high quality seeds of forage cowpea.

Training extension workers and farmers how and when to harvest the cowpea pods at MAIL-Badam Bagh

Agricultural Research Station, Kabul in October 2010 (Oushy, 2010).

Harvesting cowpea pods should be scheduled based on the maturity stage and the availability of

labor. Therefore, we recommend that cowpea growers and seed producers should plan ahead

of time for harvesting their seeds.

The cowpea seed harvesting is carried out through the following steps:

80% of the cowpea pods should be matured and dried;

Soil should not be wet and dry enough for laborers to work on it;

The first pick should be started and collected into containers;

Cowpea pods should be transferred to collective, clean and dry place;

When harvesting is completed, cowpea pods will be threshed and stored in plastic bags.



FORAGE MIXTURE

Intercropping forage legume on warm season grasses is very common practices. When sowing

cowpea with forage sudangrass or pearl millet, use three quarters of the recommended seeding

rate for cowpea with one half of the recommended rates for forage sudangrass or pearl millet.

This mixture makes excellent balanced fresh diet for animals; in addition, it makes excellent

silage and hay.

POSITION OF FORAGE COWPEA IN CROP ROTATION

Apart from its high value as a forage crop, this legume is included in crop rotations to build up

soil nitrogen as well as to break weed and disease cycles. This is particularly useful for building

up fertility in a country like Afghanistan that has been run down from over cropping of wheat-

rice. Cowpea can fix 4 to 28 kg residual nitrogen per jerib into the soil. This can give a

significant bonus to later cereal crops in the rotation. The legume cowpea crop should be

rotated with a grass crop (i.e. wheat in winter) to minimize disease buildup and take advantage

of increased soil nitrogen.

FORAGE QUALITY

Cowpea provides high quality forage suitable for growing and fattening livestock, as well as

feeding lactating dairy cows.

Crud Protein

This legume generally produces forage very high in crude protein, low in fiber, high in

digestibility and high in metabolizable energy. Crude protein levels of leaves and shoots are

usually over 20 percent, depending on the crop's stage of growth and seasonal conditions.

Stems contain only about 10 percent crude protein. Crude protein levels can be equal to that

of alfalfa and greatly superior to most tropical grasses and forage sudangrass and pearl millet.

Digestibility

The digestibility of cowpea is about 50 to 56 percent on a whole-plant basis, and appears to

vary little with the crop's age or with changes in environment. The leaf is much more digestible

than the stem. Leaf parts have 60 to 75 percent digestible dry matter (DDM %) while stems

have been analyzed as 50 to 55 DDM %. Animal intake declines as leaf availability declines. This

highlights the importance of the leaf component for yield, quality and animal production.

FORAGE PRESERVATION

Hay

Cowpea makes excellent quality hay that compares favorably with alfalfa hay. A balanced hay

diet could be produced from mixed cowpea with pearl millet or with Sudan grass.



Silage

Cowpea can produce good quality silage, particularly when mixed with forage sudangrass or

pearl millet. Like all legumes, this crop has a very low soluble sugar level which can prevent

good fermentation and production of silage. To produce good quality silage from pure crop of

cowpea, it is necessary to cut and wilt the crop to 30 to 35 percent DM before harvesting for

ensiling. Cutting and wilting 18 to 24 hours before ensiling will allow the concentration of

soluble sugars in the plants to increase and therefore ensure satisfactory fermentation of silage.

Forage cowpea plants after harvesting the pods, is suitable to produce high quality silage and hay at MAIL-

Badam Bagh Agricultural Research Station in Kabul, in October 2010 (Oushy, 2010).

Excellent silage can be made by sowing cowpea with forage sudangrass or pearl millet. These

mixtures will also need to be wilted before ensiling. When sowing cowpea with forage

sudangrass or pearl millet, sow three quarters of the recommended seeding rate for cowpeas

or lablab with one half of the recommended rates for forage sudangrass or pearl millet. This

mixture also makes excellent hay. For good quality hay, cowpea is best cut around mid-

flowering.



CONCLUSION

Forage Cowpea is a summer forage legume. It is very palatable forage producing high yields with

outstanding crude protein content. It provides a good alternative crop for hay, silage, or

pasture. It makes an excellent annual pasture legume.

It is a forage legume, which can be grown in relatively infertile sandy soils with a minimum annual rainfall of 200mm. It is a fast growing, drought resistant crop, which also improves soil

fertility by fixing atmospheric nitrogen. Cowpea forage is usually superior to other forage

legumes in terms of both quantity and quality. Cowpea crop is grown as a green manure and

also a cover crop to increase soil fertility, retain moisture and reduce soil erosion. Forage

Cowpea tends to be more productive on sandy and infertile soils than other annual forages, but still

performs best on fertile, moist soils. Cowpea, Kareem-1 variety from Egypt, proves high yielding performance and high adaptability under Afghanistan farming system and environmental conditions.

It always be mixed with pearl millet or Sudan grass to produce high quality balanced diet for

livestock in which enhance livestock production substantially without requiring additional inputs

from resource-poor livestock farmers.



REFERENCES

Koralagama, K. D. N. et al. 2002. Cowpea (Vigna unguiculata) as a human food and ruminant

forage crop for small holders in Ethiopia. www.smallstock.info/reference/BSAS/078.pdf.



ACKNOWLEDGEMENTS

I would like to acknowledge the contributions, collaboration and support of the following

groups and individuals to the development of my cowpea forage and seed production at MAIL-

Badam Bagh Agricultural Research Station fact sheet: USAID/Afghanistan, MAIL, Afghanistan,

Water and Agricultural Technology Transfer (AWATT) and Accelerating Sustainable

Agriculture Program (ASAP).

I would like also to acknowledge the contributions of Mr. Don Dwyer, DCOP ASAP, who

helped me with his team to establish the cowpea seed and forage production program at MAIL-

Badam Bagh Agricultural Research Station.

This collaborative forage field work has been carried out through an MOU between AWATT

and ASAP program on forage technology transfer at MAIL-Badam Bagh Agricultural Research

Station in Kabul, Afghanistan through the period from May to February 2011.

I would also like to acknowledge the support of the contribution of the MAIL researchers and

extension workers, faculty members of different universities in Afghanistan who participated in

team efforts to implement the forage Cowpea program in Herat, Balkh and Kabul Provinces

through 2010. These efforts enabled me to produce this fact sheet for forage Cowpea for the

good of the Afghan extension workers, researchers, farmers and livestock production in

Afghanistan.

- Hamdy Oushy

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