On-farm experiments were conducted in Chinyika Resettlement Area during the 1994/95
and 1995/96 rainy seasons at four sites to test the effectiveness of intercropping
maize with cowpea, groundnut, field bean and bambara nut in suppressing
Striga asiatica
(L.) Kuntze. During the 1994/95 rainy season maize/cowpea intercrop
supported less
Striga asiatica plant m
-2 than sole maize, while other intercrops
supported similar numbers of emerged
Striga asiatica plants m
-2 as sole
maize. Combined analysis over sites showed that the numbers of emerged
Striga
asiatica plants in the intercrops were similar to those in sole maize during
the 1995/96 season. However, during the same season the number of emerged
Striga
asiatica plants was significantly (P<0.05) lower in the maize/groundnut
intercrop at 8 weeks after crop emergence (WACE) at one site but similar at the
remaining sites. Due to moisture stress and severe competition from the parasitic
weed, no maize grain was harvested during the 1994/95 season. The maize/cowpea
intercrop had the lowest maize stover yield, while the maize/field bean intercrop
had the highest stover yield. Maize grain yields were not significantly different
for all treatments during the 1995/96 season but the partial land equivalent ratios
(PLERs) ranged from 0.8 to 1.70 indicating that intercropping maize with legumes
had an advantage over planting sole maize in
Striga asiatica infested fields.