Background and aims Locally produced bio-inoculant consortium and plant bioactive extract were studied as sustainable management options to boost maize production. Methods The field study was conducted from 13th April to 15th July 2021 and repeated on another field site from 5th May to 4th August 2023 to avoid residual effects while validating reliability of the treatments. Experiments were set up as randomized complete block design with 5 treatments including a Control (No input), Chemical (NPK fertilizer + synthetic insecticide), Organic (Poultry manure + Piper guineense), and locally produced or commercial bio-inoculant of plant growth-promoting bacteria, with 4 replicates. Results Local inoculum significantly (P < 0.05) increased maize grain yield than untreated control. Microbial and organic amendments produced comparable maize grain yield to chemical input, which were significantly higher than the untreated control (P < 0.05). The local inoculum reduced fall armyworm (FAW) infestation of maize cobs by 18% and 31% in 2021 and 2023, respectively, compared to untreated control (P < 0.05). Stem borer infestation also reduced significantly (P < 0.05) across treatments for both years, with the lowest in local inoculum (6%), followed by commercial inoculum (31%), organic (52%), chemical (42%), and control (100%) in 2021, with a similar trend observed in 2023. In 2021, amounts of plant available phosphorus and exchangeable potassium were 71 mg kg(-1) and 1010 mg kg(-1) soil, respectively, in the locally produced bio-inoculant consortium, which were significantly (P < 0.05) higher than 30 mg kg(-1) and 374 mg kg(-1) in the control, respectively, and a similar trend was observed in 2023.

Plant-parasitic nematodes pose a significant threat to finger millet crops, potentially causing yield reduction of up to 70%. Extracts derived from finger millet varieties contain potent bioactive compounds that can mitigate nematode damage and promote plant growth. This study aimed at isolating and characterizing bioactive compounds from the finger millet varieties Ikhulule, Okhale-1, and U-15; evaluating the impact of Ikhulule and U-15 extracts on the mortality of the root lesion nematode Pratylenchus vandenbergae; assessing the growth promotion effects of Ikhulule and U-15 extracts on the finger millet variety Okhale-1; and determining the efficacy of these extracts in managing plant-parasitic nematodes under greenhouse conditions. Extracts were obtained from both leaves and roots and tested in vitro for nematode mortality and in vivo for growth promotion and nematode control. The results showed that finger millet extracts exhibited strong nematicidal properties in vitro, achieving a mortality rate of up to 98% against P. vandenbergae nematodes. Applying these extracts to finger millet shoots significantly reduced nematode populations in both soil and roots and decreased the reproductive factor to below one (1), indicating an effective nematode control. The study attributes the enhanced nematicidal effects of finger millet extracts to their bioactive compounds, particularly dodecanoic acid, phytol, 1,1,4a-trimethyl-6-decahydro naphthalene, 2,3-dihydro-benzofuran, 2-methoxy-4-vinylphenol and ethyl ester, and hexadecanoic acid. These findings suggest that finger millet-derived extracts offer a natural solution for nematode management and broader agronomic benefits, ultimately contributing to overall plant health and productivity.