Abstract:
Water shortage is almost always the factor limiting agriculture production in Arid and Semi-Arid
lands (ASALs) world over. Water scarcity in today‟s world aggravated by climate change has
resulted to increased competition for the resource. This has necessitated re-evaluation of irrigation
water use management globally aimed at water conservation without overall reduced crop
productivity. Kibwezi is a semi-arid area and successful farming there requires use of water
saving irrigation technologies. To enhance the uptake of such technologies by the farmers, it is
usually necessary to demonstrate and evaluate their effect on water use and crop performance.
The objective of this study in this regard was to determine the effect of alternate furrow irrigation
(AFI) water saving technology on productivity of selected horticulture crops. The effect of
alternate furrow irrigation and conventional furrow irrigation (CFI) on growth and yields of
selected vegetables in the ASAL areas of Kenya was evaluated. Tomatoes, Collards and Cabbages
were grown at a selected site in Kibwezi for two periods in year 2010 and 2011.Growth, biomass
accumulation and yields were monitored and quantified. Applied irrigation water was also
monitored during the two seasons. In AFI half of the root system was irrigated alternately
resulting to Partial Root Drying (PRD). CFI was the conventional way of furrow irrigation and
refers to the system where every furrow was irrigated during each watering. Each treatment was
replicated three times in RCBD design. The use of AFI resulted to less use of irrigation water
with savings of upto 45%. Most parameters of growth were not significantly affected by AFI
except Leaf Area (LA) and Dry Matter (DM). Crops irrigated under AFI had 20% and 40%
reduction of LA and DM respectively compared to crops irrigated under CFI. There was no
significant reduction in overall yields. In conclusion, AFI is a reliable way to save and hence
reduce irrigation water use and this study recommends its use in arid and semi-arid areas of
Kenya.
