Scientific publications
Damien Fabrice Wassom
Mouhamed Noudi Lijouom
Gaston Mbang Elock
Rosine Barakielle Arckange Abah Bindzi
Arouna Meshuneké
Nicolas Niemenak
Biotechnology Journal International
Background: Cocoyam (Xanthosoma sagittifolium L. Schott) is an important staple crop for food security worldwide. However, its cultivation faces several constraints, including the limited availability of planting material in both quantity and quality, as well as pests, diseases (root rot) and the inaccessibility of synthetic agricultural inputs. Aims: The objective of this study is to evaluate the effects of bio stimulants derived from natural plants on the growth and protection of cocoyam planting material. Place and Duration of Study: The study was conducted at the Laboratory of Phytoprotection and Valorization of Genetic Resources of the Centre for Biotechnology, and the Laboratory of Biochemistry and Plant Physiology of Higher Teacher’s Training College, University of Yaounde 1, between March and June 2023. Methodology: A randomized block design was applied in both environments, consisting of six treatments: four bio stimulants derived from natural plant sources (BS1, BS2, BS3, BS4), a chemical fertilizer (NPK 20.10.10) as a positive control, and water as a negative control. Red and white cocoyam planting materials were watered with bio stimulants at 25% from pre-emergence in the greenhouse to emergence under shade conditions, then their effects were evaluated and correlated with agromorphological parameters, as well as growth and defense biomarkers. Statistical analyses included ANOVA with Tukey’s test (5% significance), multi-factor analysis for growth parameters, and Pearson correlation tests. Results: bio stimulants very significantly stimulated (P< 0.0001) seedling pre-emergence and emergence in terms of agromorphological parameters (number of shoots, stem diameter and height, number of leaves and leaf area) and the accumulation of growth- and defense-related biomarkers (total chlorophylls, total sugars, total phenols, flavonoids, total proteins, PAL, POX and PPO) compared with the positive (C+) and negative (C−) controls. In both varieties, bio stimulants increased the number of shoots by 56.75-92.71%, stem diameter by 77.92-93.33%, stem height by 65.73-96.02%, number of leaves by 72.50-90%, and leaf area by 36.05-82.52%. Biomarker contents ranged between 0.022 and 227.917 mg/g FM, while defense-related enzyme activities ranged between 0.036 and 0.407 µmol/min/mL compared with the controls. BS2 was the most effective treatment across all responses in both red and white cocoyam. Conclusion: These results suggest that bio stimulants may stimulate plant metabolism and biological processes, while also improving nutrient uptake. They could therefore constitute an effective tool for the biofortification, the promotion of environmentally sustainable agriculture and poverty alleviation.
