The difference in competitive/facilitative relationships between
the two years, which highlights the importance of planting date as
it relates to seedling establishment and competition for resources
as well as year-to-year variability in abiotic factors such as
precipitation amount and distribution (Fig. A1), suggests watermelon
and okra were the most competitive species in these
systems and largely influenced both yield and quality parameters.
Given that the sampling effect hypothesis held true in this
intercropping system of peanut–watemelon–okra–cowpea–pepper,
we would have expected that the species having the largest
effect on the community would contribute the greatest to LER and
would consistently overyield in mixed cropping systems as
compared to monocrop, while all other species would likely
underyield. If the complementary effect hypothesis held true in
this scenario, one would expect that all species would contribute