Abstract:
This study was conducted with the objectives of determining the effects of intercropping two
vetch species (Vicia sativa and Vicia dasycarpa) at different row spacing on yield and
nutritive values of desho grass, compatibility and changes in the soil chemical properties. The
study was designed in a factorial arrangement with Randomized Complete Block Design with
three inter-row spaces (0.50 m, 0.75 m and 1 m) and intercropping desho grass with two
vetch species (Vicia sativa ICARDA 61509 and Vicia dasycarpa lana) with three replications.
Soil samples were collected and analyzed before planting and after harvesting the forage.
Agronomic parameters, forage yield, seed yield of vetch, chemical analysis and in vitro
digestibility of forage samples were determined based on standard methods. Evaluation of
intercropping indices such as land equivalent ratio (LER), relative yield total (RYT),
competitive ratio (CR) and aggressivity were calculated. Results showed that intercropping
increased the total nitrogen content of the soil and decreased the available phosphorous of
the soil after harvesting as compared to pre planting. Significant differences (P<0.05) were
observed for all measured agronomic parameters of desho grass, with the exception of
number of tiller per plant due to interaction of intercropping with spacing. Higher total DMY
was obtained through intercropping as compared to sole whereas the forage yield
significantly decreased as the row spacing increased from 0.50 to 1 m. However, interaction
had no significant (P>0.05) effect on forage yield of desho grass and vetches, except CPY of
vetch. The chemical composition of desho grass was not affected by row spacing and
interaction ofintercropping with spacing (P>0.05). Intercropping increased the CP and
decreased the fiber contents of desho grass. Chemical composition of vetch was unaffected by
interaction of intercropping with spacing. Crude protein (CP) and acid detergent lignin of
vetches were influenced by intercropping whereas CP, neutral detergrnt fiber and acid
detergent fiber were affected by spacing (P<0.05).The in vitro dry matter digestibility
(IVDMD), in vitro organic matter digestibility (IVOMD) and metabolizable energy (ME) of
desho grass were increased by intercropping (P<0.05), but not affected by spacing and their
interaction. For vetches, intercropped Vicia dasycarpa gave higher IVDMD, IVOMD and ME
than Vicia sativa ICARDA 61509 and IVDMD increased as row spacing increased from 0.5
to1m. The LER and RYT of desho grass intercropped with vetches at different row spacing
were greater than one indicating the yield obtained in intercropping stand were more
productive than the species grown as sole with their respective spacing. Thus, the RYT was
higher by 67 % and 65% in desho grass grown with Vicia sativa ICARDA 61509 at 0.75 m
and 0.5 m spacing respectively and greater compatibility in terms of DMY was observed. In
conclusion, intercropping desho with the two vetch species at various spacing had positive
effect on total forage yield and nutritive value of desho grass. Desho grass intercropped with
Vicia sativa was a better choice for high yield and forage quality in the study area. However,
further study at different locations and over years would be vital including feeding trail using
animals to see the association effect of these forages on animal performance.
