Best practices for bio-fortified beans production

A farmer sorts out beans. PHOTO/MICHEAL J SSALI 

What you need to know:

  • To facilitate garden inspection, spraying of pesticides, and weeding it is advisable to plant the beans in rows 50 centimetres apart and 10 centimetres from plant to plant.

Beans form a vital part of nutrition in our diet. They are a major part of the daily menu in prisons, our schools and other institutions of learning as well as restaurants. 
The Food and Agriculture Organisation (FAO) of the United Nations gives 10 reasons why we should eat beans. 

They are low in fat. They are low in sodium. They are a good source of protein. They are an excellent supplier of fibre.
They provide potassium. They are an excellent source of folate. They have low glycemic index. They are cholesterol free and are gluten free.

Big demand 
Farmers are therefore encouraged to grow beans because of the big demand for the food crop. In a bid to boost nutrition and food security researchers under the National Agriculture Research Organisation (Naro) came up with a number bean varieties that are high yielding, drought and disease tolerant, and nutritionally enhanced (bio-fortified) --- rich in iron and zinc and highly recommended for pregnant women and children.

During a conversation with Mr Charles Katamba, programme manager of Community Enterprises Development Organisation (Cedo), an NGO that promotes bean production in the Masaka Sub-region, he said that with good weather and agronomic practices it is possible to harvest as much as 3,800 kilogrammes from one hectare for most of the bean varieties.

Seed selection 
Katamba who is also a trained agriculturist said that successful bean production begins with good seed selection. “The farmer has got to be clear what bean variety he wants to grow,” he tells Seeds of Gold.

“Bean production has become a big money making activity and farmers have to grow them with the market demands in mind. It is the reason we are working with Naro and other organisations to promote the use of improved bean seeds by farmers. The bean seeds should be high yielding, clean, and disease-free,” he says.

Major varieties 

Katamba further revealed that there are mainly two types of beans grown in Uganda --- climbers, and bush type. The bush type is grown in most parts of Uganda while the climbers are mainly grown in some districts including Sironko and Kabale.

Generally, according to him, bean production is more successful in areas where temperatures are between 15 degrees and 32 degrees centigrade and where rainfall is between moderate and light in the last few weeks of the growing season.

Contract farming 
Cedo gets into contract with local farmers in the Masaka region (about seven districts) to grow improved bean varieties and undertakes to supervise their farm activities and to provide inputs which include seeds, on credit where necessary. After harvest Cedo buys the beans from the farmers at an agreed price for distribution to other farmers to plant as seed.

Katamba  says that after deciding on which seed to plant, the next important step for the farmer is good seed bed preparation. 
“A well prepared garden results in uniform growth of the beans. If there are any stubborn weeds that cannot be easily dug out, they may be killed with a herbicide but this should be some three weeks before ploughing,” says Katamba.

Planting 
He also says at the time of planting the soil should be moist enough to facilitate quick seed germination which should take place within seven days after planting. The best time to plant seeds is the beginning of the rainy season. To facilitate garden inspection, spraying of pesticides, and weeding it is advisable to plant the beans in rows 50 centimetres apart and 10 centimetres from plant to plant.

Between 25 and 30 kilogrammes of bean seeds should be enough for planting in an acre.

Fertiliser application 
The soil must be fertile to get the best results and if it lacks the necessary fertility ingredients the farmer should replenish it by applying well decomposed organic manures such as animal droppings and crop residues. Inorganic fertilisers such as NPK, DAP or urea can be used too for soil enrichment. The bean garden must be weed-free but care should be taken not to weed during flowering because if the flowers drop the harvest will definitely be low.

Pest management 
Katamba further says the next worry for the farmer should be pest management. The commonest pests are the bean fly, flower thrips, and Aphids, which can be avoided by early planting and use of any recommended systematic pesticides. 

Planting clean seed, improving soil fertility, practicing crop rotation, and timely disposal of diseased plants are also quite preventive measures. He however discloses that the bean seed varieties Cedo gives out to farmers are tolerant to most common bean diseases including anthracnose, angular leaf spot, common bacterial blight, rust and bean root rot.

Harvesting 
Katamba advises farmers to harvest the beans quite early to minimise the risk of weevil attack. The farmer may harvest fresh beans for eating when the plant leaves begin to turn yellow. If the farmer has to harvest dry beans the plants ought to be fully pulled from the ground and placed under the sun on clean tarpaulins or mats or concrete ground to dry. He can then thresh the pods by beating with sticks.

He ought to winnow and dry the beans until they get to 14 per cent moisture content level. These days there are hermetic bags sold in some farmers’ shops specially made for storing grain and protecting it from weevils and moisture.

If post-harvest handling for beans is not properly carried out, aflatoxins and fumonisns, which are poisons released by certain moulds can develop in the beans. Aflatoxins are a big issue today, especially following the recent rejection of Uganda’s maize by Kenya over allegations that it is infested with aflatoxins. The poisons are said to cause cancer and liver damage and nobody wants to eat beans that can lead to health problems.

Before storage the farmer should sort out the beans by removing discoloured beans, pest damaged beans, immature beans, shrivelled beans, and germinated beans. No foreign matter or contrasting bean varieties should be left in harvested beans.

Advice
If post-harvest handling for beans is not properly carried out, aflatoxins and fumonisns which are poisons released by certain moulds can develop in the beans.  Aflatoxins are a big issue today especially following the recent rejection of Uganda’s maize by Kenya over allegations that it is infested with aflatoxins.