Use of poor quality bean seed, a major factor to low bean yield in Kenya

Common bean (Phaseolus vulgaris L.) is one of the major food legumes widely grown in the world. In Kenya, beans are produced in most households and are the second most important food crop after maize .Beans are very versatile in their contribution to household`s food income, diet, health and environmental security. Together with other pulses they provide a cheaper alternative source of protein and household food security to the low-income earners in town and the rural poor population especially due to the fact that, animal protein sources are either very scarce or too expensive.

Beyond their contribution to human nutrition and economic wellbeing, beans are incorporated in intensive agricultural production system as rotation crop since are widely adaptable, are easy to grow, are tolerant to shades, have a shorter growth cycle and they help improve soil nutrition through nitrogen fixation. Varieties produced are many and diverse, however, many farmers prefer the large seed speckled varieties probably because they are moderately tolerant to most common diseases and are popular in the market.

Low productivity amidst high demand

Over the years, the demand for beans has been on the increase. On the contrary, production trends have been on decline since the year 2004. To help meet the deficit, the country has been importing nearly fifty percent of its annual bean demand from its neighbors’. This has exposed the country`s food security. This yield gap is caused by several constraints, key among them the use of poor quality bean seed as a result of unavailability and or inaccessibility and to an extent prohibitive cost of certified seed.

Oblivious of the negative effect of poor quality seeds, small scale bean farmers have continued to use farm saved bean seed from the previous harvest, borrowed from neighbor or purchased from local markets. Such seed are an important source of disease inoculums for short and long distance introduction, dissemination and spread. Moreover, more than 50% of major bean diseases of economic importance are seed borne. Further, given that small scale farmers tend to retain seeds for several seasons, there is a likelihood that seed borne disease pathogen inoculum may build up into a threshold that may lead to disease outbreak. When farmers eventually plant such seeds, the final stand establishment is negatively affected due to increased incidence of seed rots, seedling decay, pre and post emergency mortality and seed abnormalities which results to the low bean grain yield.

Way forward

Underlying the constraints prohibiting higher bean yield at the household level, the demand for beans continues to be high, consequently, rural households continues to be negatively affected and may suffer from food insecurity, nutritional deficiency and reduced income. Thus, there is every need to deliberately come up with specific actions plan aimed at increasing bean productivity among the small scale farmers in the Kenya and in the region such as;

1. Up scaling effort of producing and validating better yielding varieties by the government, research and seed merchants.
2. On farm training of small scale farmers via field demonstration on the advantages of using certified bean seeds over farm saved seed.
3. County government and stakeholders to take lead in developing and disseminating simple bean production guidelines that will enable small scale increase farm level productivity.
4. Where farmers cannot access certified seeds, they should be exposed to techniques that improve the seed physical quality and field performance of the farm saved seed such as purity analysis, seed treatment and inoculation at the farm level.

Thomas Kariuki

Research/Production

Simlaw seed Co Ltd