SPAD values were influenced by the fertilizer treatment
(P < 0.001) but not by earthworm activity (P > 0.05) (Table 4).
Regardless of cultivation practice, SPAD values were always highest
in mineral and lowest in compost treatments (P < 0.05). Vermicompost
led to intermediate SPAD values for the two maize plantings
(P < 0.05 in all the case) and to similar values as the mineral treatment
for tomato (P > 0.05).
Although no significant difference in above-ground plant
biomass was observed for the first maize planting (P > 0.05 in
all the cases) (Fig. 2), our study showed increased biomass for
tomato and the second maize planting when mineral fertilizer
and vermicompost were used, without a significant difference