In a bid to increase the number of genotypes reaching farmers, on-farm
trails were conducted in 2001/2002 with the aim of increasing the
number of genotypes available to farmers to be evaluated for
performance, adaptation and acceptability. Twenty improved genotypes
were planted in Lira, Nakasongola, Gulu, Kumi and Katakwi districts
using augmented design. The results indicated that cassava mosaic
disease (CMD) varied from location to location but was more influenced
by the genotype than the environment. The highest SMD severity (>4)
was recorded among the farmers" local varieties across all
environments, followed by Alice local (3.8 ±0.4) in Nakasongola
and Lira (2.8 ±0.2) districts and I 60142 (3.0 ±0.0) in Kumi
and Lira (2.8 ±0.2) districts. Six clones (MM96/0245,
MM96/0561,I92/2324, MM96/3585, MM96/4589 and MM96/0264) showed
resistance (score 1 for CMD) while the rest had severity scores below
the average (2.5). At harvest, the highest yield (60.8 ±3.7 t
ha-1) was obtained from Alice local followed by clone MM96/0561 (59.5
±6.6 t ha-1) in Nakasongola district and clone MM96/4614 (52.5
±13.2 t ha-1) in Lira district. The lowest yield was from clone
MM96/3585 (10.3 ±4.2 t ha-1) followed by Oko Iyawo (1) 99(14.2
±4.2 t ha-1) in Kumi district. All the varieties tested were
either sweet or slightly bitter with the scores of 1 or 2,
respectively. Genotype MH97/2961 was the most preferred in Kumi and
Lira districts, while it was third in Nakasongola district. All these
genotypes also had a sweet taste for cooking. The most preferred
genotypes in Nakasongola were TME 5 and MM96/5312 and had a sweet taste
for cooking. The genotype by environment analysis indicated that
genotypes TME 5, MM96/1419, I92/0427, and MH97/044 (2) UG were the most
stable and adapted across all environments while MM96/4614 and Alice
local were more specific for Lira and Nakasongola, respectively. These
findings provide a basis for recommendations with regard to cultivation
and preference of cassava genotypes in different environments