Maize-legume intercropping and botanical Piper mitigating effect on pest populations while enhancing the yield of maize

Climate change poses a wave of pests, devastating crops and jeopardizing the quest to feed more than 8 billion people globally. This can be seen in fall armyworm and snails being a nightmare to maize productivity. Thus this study was set up to increase maize productivity by reducing maize pests (FAW and snails) in maize-legume intercropping with locally produced organic (botanical) insecticide and utilizing legume nitrogen-fixing ability for maize growth and production. This work was done at the University of Buea and had nine treatments, and each was replicated three times in a randomized complete block design. The main crop maize, was intercropped with beans and cowpea. Data on fall armyworm incidence and severity, snail incidence and severity, height of plant, leaf number, girth of stem, leaf area index, and maize grain dry weight were collected. Data was subjected to ANOVA, P < 0.05, using SPSSv26 and graphs drawn with excel. More damaged plants for FAW and snails occurred in control, 14, and 11 plants, respectively, and were significantly different (P < 0.05) among treatments. The most pests were recorded in control 4 FAW and 3 snails per plant which varied statistically (P <0.05). Maize growth parameters (height of plant, leaf number, girth of stem, leaf area index) differed significantly (P < 0.05) across treatments, with control recording the least (206 cm, 13, 7.4 cm and 641 cm² respectively). The best results were obtained with an intercrop of maize and cowpea along with synthetic or Piper pesticide. (236.4 cm, 16, 10.6 cm and 730.6 cm² respectively) with no statistical difference. The highest maize yield was recorded in maize+cowpea intercrop coupled with Piper or synthetic insecticide (6.13 and 5.93 t/ha, respectively), with significant (P < 0.05) difference. Plant damage was connected adversely with yield (r = −0.90 for FAW, r = −0.94 for snail) and favourably with the number of pests (r = 0.70 for FAW, r = 0.86 for snail).

Conclusion

Intercropping and Piper emulsion effectively managed maize pests, while boosting maize output. As a result, farmers can utilize this maize-dwarf bean and maize-cowpea intercrop, as well as the organic Piper emulsion approach, as a sustainable crop protection and fertilizer management strategy to increase production.