Abstract:
A study was conducted in the southern rangelands of Kenya to establish the
nutritive value of ecotypes of Cenchrus ciliaris and Eragrostis superba. A total
of eleven ecotypes for C. ciliaris and nine for E. superba collected from sites
representative of medium to low potential agro-ecological zones (III to VI) were
established at KALRO Kiboko research centre in a randomized complete block
design. Plant samples collected were analysed for in vitro dry matter digestibility
(INVDMD), crude protein (CP), Crude fibre (CF), ash content and percent dry
matter yield (%DM).
Significant variations were observed among C. ciliaris ecotypes. KBK2 and
KLF2 collections had higher ash content than the rest of the ecotypes at p<0.05.
Also, KBK2 had higher values (p<0.05) than TVT1 in INVDMD with no
variation between the rest of the ecotypes. Positive correlations (p<0.05) were
recorded between INVDMD with stem thickness and leaf breadth and CP with
leaf length, plant height, heading time and stem thickness. Late flowering and
robust ecotypes of C. ciliaris were higher in CP while CF negatively correlated
(p<0.05) with plant height and leaf length. Significant variations between E.
superba ecotypes resulted in 3 major clusters that combined ecotypes from
different sites. Kiboko (KBK2) and Kilifi (KLF1) collections clustered together
with high CF, CP and INVDMD while TVT3 was grouped alone with higher CP
and low CF at p<0.05. Mean ash content for C. ciliaris (13.6%) was higher than
E. superba mean (8.6). The two species had no difference in the other four nutritive value components. Significant variations existed among the study
collections that could potentially be exploited to meet different feed
requirements. Morphological traits could be used to select for high INVDMD or
CP levels among and within C. ciliaris ecotypes. Selection for low CF should
target shorter ecotypes of C. ciliaris with shorter leaves.
