Host status and host sensitivity of Kickapoo white tepary bean to Meloidogyne entorolobii

Abstract

Tepary bean (Phaseolus acutifolius A. Gray) is a drought tolerant leguminous crop and due to its multi-purpose use, it can easily be incorporated into different production systems. It being an undertilised crop, its production is usually relegated to poor sandy soils that are highly prone to root-knot nematodes (Meloidogyne species). Commonly communal producers of tepary beans use retained seeds with no knowledge of the nematode resistance status of the seeds. Hence the objective of the study was to determine whether Meloidogyne entorolobii will be able to reproduce on the Kickapoo white tepary bean and cause a reduction in the plant's growth variables. To achieve this objective, Kickapoo white tepary bean seedlings were exposed to 0, 25, 50, 125, 250, 625, 1250 and 3125 M. entorolobii eggs and second-stage juveniles (J2) in 2021 and validated in 2022 under shade-net conditions. At 56 days after inoculation, plant and nematode variables were collected and reproductive factor (Rf) was computed. Plant growth variables were not reduced whereas, nematode variables increased with an increase in nematode levels. In both experiments the Rf values were above a unity for all inoculation levels, indicating that nematodes were able to reproduce. In conclusion, Kickapoo white tepary bean is tolerant to M. entorolobii.