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Crop Research

Biological indices of runner bean (Phaseolus coccineus) seeds to priming and drying with cucurbitacin phytonematicides

 


DOI: 10.31830/2454-1761.2026.CR-1086    | Article Id: CR-1086 | Page : 160-164
Citation :- Biological indices of runner bean (Phaseolus coccineus) seeds to priming and drying with cucurbitacin phytonematicides. Crop Res. 61: 160-164
PHATU WILLIAM MASHELA AND KGABO MARTHA POFU phatu.mashela@ul.ac.za
Address : University of Limpopo, Department of Plant Production, Soil Science and Agricultural Engineering, Private Bag X1106, Sovenga, 0727, South Africa
Submitted Date : 14-11-2025
Accepted Date : 24-02-2026
Online Published:

Abstract

Phytonematicide priming methods often give uneven results, mainly due to variability in how seeds respond to allelochemicals. The movement and effect of cucurbitacin-rich priming solutions inside seed embryos, especially with different emergence patterns, are still not clearly understood. Therefore, it is necessary to evaluate the biological sensitivity and safe stimulatory concentrations for runner bean seeds primed using PAD technology with cucurbitacin-based phytonematicides. This study investigated the biological indices of runner bean (Phaseolus coccineus) seeds ten days after priming in cucurbitacin-based phytonematicide solutions during 2024 at the University of Limpopo, South Africa. Runner bean seeds were primed in geometric series concentrations (0–64%) of Nemarioc-AL (containing cucurbitacin A) and Nemafric-BL (containing cucurbitacin B) for six hours, dried at 25°C, and germinated inside a temperature-controlled growth chamber. Data on germination percentage, radicle length, plumule height, and plumule diameter were analysed using the Curve-fitting Allelochemical Response Dose (CARD) algorithm to generate biological indices, allowing the computation of midpoint stimulation concentration. Positive quadratic relationships were observed between increasing phytonematicide concentrations and most germination variables, with R² values ranging from 89% to 99%. Negative quadratic relationships were not included in the in biological indices. The calculated overall sensitivity indices were 39 for Nemarioc-AL and 14 for Nemafric-BL, indicating high tolerance of runner bean seeds to both products. The respective MPC values were 1.05% and 0.58%, which supported 100% germination during validation tests. These findings demonstrate the potential of PAD technology for integrating phytonematicides into seed-based nematode management strategies without inducing phytotoxicity, particularly for crops exhibiting hypogenous emergence. In conclusion, the findings confirm that seeds with hypogenous emergence can serve as effective carriers of cucurbitacin phytonematicides,

Keywords

Biological indices CARD algorithm cucurbitacin phytonematicides PAD technology runner bean seed priming

References

Causton, D. R. (1987). A biologist’s advanced mathematics. Allen and Unwin: Auckland Zealand.
Chen, J. C., Chiu, M. H., Nie, R. L., Cordell, G. A. and S. X. Qiu. (2005). Cucurbitacins and cucurbitane glycosides: Structures and biological activities. Nat. Prod. Rep. 22: 794-95.
Dube, Z. P. (2016). Nemarioc-AL and Nemafric-BL phytonematicides: Bioactivities in nematodes, crops and soil. PhD thesis, University of Limpopo, Sovenga, South Africa.
Hartmann, H. T., Kester, D. E., Davies, F. T. and Geneve, R. L. (2002). Plant propagation: principles and practices, Prentice Hall, New Jersey, 7th ed. pp: 199-206.
Karimi, A., Tabari, M., Javanmard, Z. and Bader, M. K. F. (2022). Drought effects on morpho-physiological and biochemical traits in Persian oak and black poplar seedlings. Forests 13: doi:10.3390/f13030399.
Liu, D. L. and M. An. (2005).  Implementation of CARD: Curve-fitting allelochemical response data. Nonlinearity Biol. Toxicol. Med. 3: 235-44.
Liu, D. L., An, M., Johnson, I. R. and J. V. Lovett. (2003). Mathematical modelling of allelopathy. III. A model for curve-fitting allelochemical dose responses. Nonlinearity Biol. Toxicol. Med. 1: 37-50.
Mafeo, T. P. (2012). Responses of economically important crops to crude extracts of Cucumis myriocarpus fruit when used as a pre-emergent bio-nematicide. PhD Thesis, University of Limpopo, Sovenga, South Africa.
Maila, M. Y. (2015). Overcoming seed dormancy and development of in vitro propagation protocols in indigenous Cucumis species for use as alternative crops in various industries. PhD thesis, University of Limpopo, South Africa.
Mashela, P. W. (2002). Ground wild cucumber fruits suppress numbers of Meloidogyne incognita on tomato in microplots. Nematropica 32: 13-19.
Mashela, P. W., Dube, Z. P. and Pofu, K. M. (2015). Managing the phytotoxicity and inconsistent nematode suppression in soil amended with phytonematicides. In: M. K. Meghvansi, A. Varma (eds.), Organic amendments and soil suppressiveness in slant disease management, Soil Biol. 46: 147-73.
Mashela, P. W., Pofu, K. M. and. Bopape-Mabapa, M. P. (2022). Efficacy of seed priming with cucurbitacin phytonematicides against Meloidogyne incognita on pea. Front. Microbiol. 13: doi:10.3389/fmicb.2022.863808.
Mashela, P. W., Shokoohi, E. and Pofu, K. M. (2020). Shelf-life in cucurbitacin-containing phytonematicides: Non-conformity to Arrhenius model. Plos One 15:   doi:10.1371/journal.pone.0227959.
Mashela, P.W., De-Waele, D., Dube, Z., Khosa, M. C., Pofu, K. M., Tefu, G., Daneel, M. S. and Fourie, H. (2017). Alternative nematode management strategies. In Nematology in South Africa: A view from the 21st century. Springer, Cha. pp. 151-81.
Parmar, S. R., Dhruv, J. J. and Dobariya, J. D. (2023). Effect of seed priming on morphological characters with melatonin and nematicide in tomato (Solanum lycopersicum L.).  Pharma Innov. J. 12: 2155-59.
Shadung, K. G. (2016). Quality protocols for Nemarioc-AL and Nemafric-BL phytonematicides. Ph.D. thesis, University of Limpopo, Sovenga, South Africa.
Yates, P., Janiol, J. Lic, J. and Song, B. (2024). Nematocidal potential of phenolic acids: Phytochemical seed-coating approach to soybean cyst nematode management. Plants 13: doi:10.3390/plants13020319.

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