Production Practices and Quality Assessment of Food Crops. Vol. 1

170 Chris A. Shisanya
The current National Development Plan stresses the fact that ASALs will receive
increasing attention albeit at a higher cost in recognition of their important contribution
to the national development (Republic of Kenya, 2002).
The major environmental factors limiting crop production in the ASALs of Kenya
are high potential evaporation and rainfall, with the latter being variable and
unpredictable in space and time (Keya, 1998). It should be noted that these areas
have only short to very short agrohumid periods (AHPs) (potential growing periods)
of about 40–45 and 85–105 days (Hornetz et al., 2000) with low soil moisture supply
during the main part of the rainy season and frequent dry spells (Hornetz, 1997).
Apart from environmental limitations, the new farming communities in these ASALs
lack the background knowledge in selecting crops and farming strategies well suited
to the stabilization and maximization of food production in their diminished rainfall
circumstances (Shisanya, 1999). As Hornetz (1997) had earlier observed, the new
communities in these ASALs are unconscious of the carrying capacity of their
new fields, hence are aggravating the problems of desertification and finally causing
food crisis and famine.
Though it can be observed in the relatively wetter parts of the drylands that
smallholder farmers have started to cultivate drought resistant leguminous crops like
pigeon peas (Cajanus cajan) and cowpeas (Vigna unguiculata), there is still a lack
of ecologically adapted crops in the potential cropping areas (Hornetz, 1997). This
is particularly the case in the drier parts of the agroecological zones Lower-Lower
midland 5 and 6, according to Jaetzold and Schmidt (1983), which have until recently
been dominated by extensive grazing systems. The reason for this is that on the
one hand the pastoralists have little interest in cultivating food and fodder crops,
while on the other hand the new settlers from the high potential areas generally
possess seeds of crops with longer vegetation cycles and less ability to adapt to
high temperature and water stress typical of their new environment (Hornetz,
1997).
A number of researchers have proposed various strategies that need to be adopted
in Kenya for the development of sustainable food production systems in the ASALs
and at the same time reducing the vulnerability of small-scale farmers to crop failures
(Jaetzold and Schmidt, 1983; Zoebisch, 1986; Hornetz, 1988; 1990; 1991a; 1991b;
1997; Maingi et al., 1999; Hornetz et al., 2000; Gitonga et al., 1999; Shisanya, 1996;
1998; 2002; Maingi et al., 2001). Some of the proposed agroecologically suitable
farming strategies include: ‘water harvesting’ systems (e.g. Matuta), run-off irrigation,
agroforestry and the introduction of drought resistant ‘minor crops’, and
use of biofertilizers. Already, some of these proposed measures have been operationalised
in the ASALs of Kenya (Shisanya, 2002; Maingi et al., 2001; Hornetz
et al., 2000 and Gitonga et al., 1999).