In the remote Zambezi valley and Rushinga district of Zimbabwe, little rain falls and the majority of households live in absolute poverty. Farmers in this region depend on dry-land agriculture, predominantly growing sorghum, millet, maize and groundnuts to meet their basic requirements.
Introducing guar
Recently the promotion of guar production (see box below) in the area has offered farmers a low input, yet high value and competitive crop, to sell to local and national markets. As an important added extra, since it is a legume, the guar bean improves soil fertility. Guar’s root nodules contain nitrogen-fixing bacteria, making it an excellent soil-building crop with respect to available nitrogen. In addition, when ploughed under, guar crop residues improve the yields of the succeeding crops, and its protein rich crop residue can be used as a stock feed to significantly boost livestock productivity.
Understanding this potential, the ITDG (Intermediate Technology Development Group), whose aim is to build the technical skills of small-scale producer communities in the region, introduced members of the communities to the benefits of guar bean as a cash crop. The guar bean became popular because it served to increase income and generate employment opportunities for those with no land of their own.
During 2002, the Chindito family was just one among many who benefited from ITDG’s intervention when drought struck the area. Mrs Chindito recalls “the poor rains were bad for all farmers. We knew how to grow maize and cotton but when the rains did not come, it was very difficult for us guar bean appeared to be our only salvation; we were able to harvest and sell something.”
As a result of their crop that year, Mr Chindito was chosen by members of his community to coordinate guar production in their area. During the 2002/03 season, the Chindito family joined others to establish a group plot of guar beans. The group was allocated the plot by their village head and they are investing the profits released in previous years into this community initiative.
ITDG is now working with producers to enable them to take advantage of the market opportunities available to them, offering support and advice on where and how to sell their product, ensuring they achieve a fair price. The guar bean production project seeks to create a win win situation among small-scale producers and bigger business – and this is obviously achievable.
Moving forward
More effort needs to be directed towards training farmers to improve their knowledge and practices in the growing of the crop. This will increase both yields and returns received by farmers.
Contributed by:
Intermediate Technology Development Group
The Schumacher Centre for Technology & Development
Bourton-on-Dunsmore
RUGBY
CV23 9QZ
United Kingdom
Summary
The Guar bean is an annual legume grown principally in India and Pakistan, with smaller crops grown in the USA, Australia and Africa. Guar beans are drought-tolerant and can be eaten green like snap beans, fed to cattle or used as a green manure. The bean contains galactomannan gum which forms a gel in water commonly known as guar gum. And as such is used in dairy products like ice cream and as a stabilizer in cheese and cold-meat processing, and can also be used in industrial applications such as the paper and textile industry, ore flotation or the manufacturing of explosives. The current demand for guar gum outstrips supply and guar beans are being introduced into new growing areas. At this moment about 40% of the world production of guar gum comes from India.
Growth Habits
Guar is an upright, coarse-growing summer annual legume known for its drought resistance. Its deep taproots reach moisture deep below the soil surface. Most of the improved varieties of guar grow to be 18 to 40 in. tall. Pods are generally 1 1/2 to 4 in. long and contain 5 to 12 seeds each. Seeds vary from dull-white to pink to light gray or black and range from 900 to 1,600 seeds/oz.
Climate
Guar tolerates high temperatures and dry conditions and is adapted to arid and semi-arid climates. Optimum temperature for root development is 77 to 95°F. When moisture is limited, the plant stops growing but doesn't die. While intermittent growth helps the plant survive drought, it also delays maturity. Growing season ranges from 60-90 days (determinate varieties) to 120-150 days (indeterminate varieties). Guar responds to irrigation during dry periods. It is grown without irrigation in areas with 10 to 40 in. of annual rainfall. Excessive rain or humidity after maturity causes the beans to turn black and shrivel, reducing their quality and marketability.
Soil
Guar grows well under a wide range of soil conditions. It performs best on fertile, medium-textured and sandy loam soils with good structure and well-drained subsoil. Guar is susceptible to water logging. Guar is considered to be tolerant of both soil salinity and alkalinity. Guar is an excellent soil-improving crop and fits well in a crop-rotation program with grain sorghum, small grains or vegetables. In Australia, guar was found to add 196 lb N/acre to the soil-plant system over three years. Increased yields can be expected from crops following guar because of increased soil nitrogen reserves.
Seed Preparation and Germination
Select seed that is uniform in color and size and is free from other crop and weed seed. a. Seedbed Preparation
The seedbed should be firm and weed-free. Soil in the row should be ridged slightly to facilitate harvest of low-set beans. b. Seeding Date
Guar should be planted when soil temperature is above 70°F; the optimum soil temperature for germination is 86°F. A warm seedbed, adequate soil moisture and warm growing weather are essential for establishment of a stand.
Method of Planting
Guar is usually planted in 36 to 40 in. rows with a row crop planter. However, it can be broadcast seeded or planted in narrower rows with a grain drill if moisture is adequate. A planting depth of 1 to 1 1/2 in. is usually recommended.
Rate of Planting
Although some studies have found little effect on yield when seeding rates ranged from 5 to 44 lb seed/acre, other researchers have indicated an optimum seeding rate of 5 to 9 viable seeds/ft of row (30 in. rows).
Harvesting
Since guar beans generally do not shatter, the crop can be direct-combined as soon after maturity as possible. At maturity, the seedpods are brown and dry, and seed moisture content is less than 14%.
