Application of bioinoculants in combating Striga Hermonthica (Del.) Benth infestation in maize

Striga hermonthica (Del.) Benth is an obligate root parasitic flowering plant capable of causing 30-90% yield loss in cereal fields thereby constituting a huge threat to food security. Despite its economic importance, effective and eco-friendly management measures for this weed have not yet been found. Hence, this study explores the application of bioinoculants in combating S. hermonthica infestation in maize. A total of 63 bacteria isolates originally obtained from maize rhizosphere were screened for ammonia production, siderophore production, phosphate solubilization, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, and ethylene gas quantification using standard protocols. The screened bacteria isolates were subjected to both in-vitro and in-vivo experiments arranged in a completely randomized design (CRD) with three replications, to investigate the potential of the screened bioinoculant to combat against infestation in maize. Data gathered on the growth, biomass, and stalk lodging caused by Striga infestation were subjected to ANOVA analysis at p ≤ 0.05.

A total of 11 prospective bioinoculants were derived from the Plant-Growth Promoting Rhizobacteria (PGPR) and ethylene productions, while the in-vitro and in-vivo evaluation showed that isolates; B2 (Enterobacter asburiae OR044418), B3 (Enterobacter chengduensis, OR044419), B4 (Priestia aryabhattai OR044420), B7 (Priestia megaterium OR044423), NWUAB 12 (Pseudomonas koreensis MH399240), enhanced both growth and biomass production and exhibited strong biocontrol potential against Striga. Their performances in managing the Striga-induced damage to maize shows B3 (Enterobacter chengduensis) > B7 (Priestia megaterium) > B2 (Enterobacter asburiae) > NWUAB 12 (Pseudomonas koreensis) > B4 (Priestia aryabhattai) as the order of performance.

This research demonstrated that bioinoculants hold great promise in controlling Striga infestation.