| dc.description.abstract | In Kenya, the consumption of African indigenous leafy vegetables (AlLY's) is increasing due to
the public awareness on these vegetable's contribution to nutritional and economic values.
However, several factors limit their production. The objective of this study was to improve the
productivity of these vegetables by addressing their nutritional requirements and the insect pests
problem The study which was carried out in Wundanyi location, Taita district, sought to
establish major AlLY's production constraints and to develop strategies to deal with the major
constraints. This was done through Participatory Rural Appraisal (PRA) and a structured
questionnaire. A total of 70 AlLY's producing farmers participated in the PRA and were also
interviewed using the structured questionnaire.
On farm studies were carried out in farmers' fields. Amaranthus hybridus and Solanum scabrum
were selected based on preference by the community. Four plantings were done between May
2008 and February 2009. Farm yard manure levels at rates of 2Ot/ha. 40t/ha, 60t/ha, poultry
manure at rate of 40t/ha, 2Ot/ha, 40t/ha, 60t/ha farm yard manure each top dressed with CAN-
1030kg/ha, DAP-200kglha top dressed with CAN-l 030kg/ha, farmer practice and a control, were
evaluated for yield improvement. This was carried out in replicated field experiments. A study
was also carried out to identify and quantify the pest complex in the selected study site. In
addition, experiments to establish an action threshold for the major insect pest and assessment of
different IPM components (Azadiractin, Dimethoate, Lambda-Cyhalothrin) were also carried out
in farmer's fields.
Results of the PRA and questionnaire showed that the area had several resources such as rivers
and streams, which if well utilized could assure farmers of good AlLY's yields. However, it was
revealed that AlLY's are allocated very small portion ofthe farmers' total land. Though, most of
the farmers used farmyard manures, they were not aware of the recommended rates. Several
production constraints were highlighted. These included low soil fertility, low yields due to lack
of information on AIL V's agrononuc packages, insect pests and diseases, poor market
organization and lack of capital. Others were, lack of quality seed, lack of irrigation facilities and
lack of information on whether their cooking procedures preserve nutrients in the vegetables.
The on farm study on production packages indicated that, incorporation of farmyard manure (20,
40, 60tlha), poultry manure (40tlha) and inorganic nitrogen (N), significantly increased plant
growth parameters (plant height, canopy width, number of branches, stem diameter) and yields.
Yields obtained from plants which were grown with organic manures top dressed with inorganic
Nwere higher than those from plants with manures alone.
There were a variety of insect pests on both vegetables occurring at different stages of plant
growth. Insects belonging to six insect orders (Coleoptera, Lepidoptera, Orthoptera, Homoptera,
Heteroptera and Diptera) were identified as pests on the two vegetables. Aphids were identified
as a major pest of both vegetables. However, red spider mites were a major pest of Solanum
scabrum occurring during the dry hot weather. 10 aphids/ young leaf was established as an action
threshold, a point after which the leaf begins to curl making the produce unmarketable. The
management studies revealed that Azadiractin, Dimethoate and Lambda -Cyhalothrin
significantly reduced aphids and red spider mites populations and maintained the quality of the
produce for marketing. Cattle manure levels at the rates of 20tlha, 40tlha, 60tlha either alone or
top dressed with C.A.N-I030kglha and 40tlha poultry manure are recommended for use by small
scale farmers to improve yields of AILV's, thus their incomes, health and livelihoods. The
information on the pest complex and their damages can be used in designing management
strategies for insect and mite pests, which have been identified as a major AILV's production
constraint in many parts of the country. The action threshold could be adopted by AIL V's
producers to encourage rational pesticide use in AILV's production as components of Integrated
Pest Management | en |
