Integrated control of Striga hermonthica using Parkia biglobosa products and mycoherbicide (Fusarium oxysporum) in maize (Zea mays L.) in the savanna

Objective: To evaluate the efficacy of a granular mycoherbicide (Fusarium oxysporum) formulation and Parkia (Parkia biglobosa) products under greenhouse conditions for eventual use as an integrated Striga management package under field conditions in the Nigerian Savanna. Methodology and results: Two maize varieties (Across 97 TZL and farmers’ local) and two Striga seed density (5 and 10 c.c/pot) were used in two trials. Two and three Striga control methods (with and without F. oxysporum isolated from Striga hermonthica stems (Marley et al. 1999)); seed soaking for 20 minutes before planting in Parkia products (fruit powder, seed powder) and distilled water as control were used in the first and second trials, respectively. In the two trials, the design used was a randomized complete design with three (3) replications. Generally, the number of emerged Striga was significantly higher in fields planted with the farmers’ local variety than in fields with Across 97 TZL in both trials and throughout the period of observation. The use of either F. oxysporum or Parkia products (fruit and seed powder) resulted in significantly fewer number of emerged Striga, lower Striga dry weight than their corresponding checks (No Fusarium and distilled water). The number of emerged Striga as influenced by Striga seed density (Striga infestation levels) was only significantly different at 56 days after sowing (DAS) in the first trial (evaluating Fusarium), while other periods of observation did not produce consistent results. However, in the second trial, (evaluating Parkia products), the higher Striga seed density (10c.c/pot) produced a corresponding higher number of emerged Striga plants than the lower density (5c.c/pot) throughout the period of observations, although the difference was not significant (P<0.05) Conclusions and application of findings: The results demonstrate the high potential of using mycoherbicides and Parkia based products for the control of S. hermonthica. Parkia trees abound in the Savanna and thus products can be easily and cheaply obtained. Likewise, maize grits can be used to propagate F. oxysporum quickly and cheaply by the farmers’ instead of using the more expensive potato dextrose agar. The implication of these findings is that farmers can easily adopt these practices in integrated management packages for enhanced control of the parasitic plant under field conditions.