Screening of Vigna subterranean L. Verdc. accessions for waterlogging stress tolerance

Abstract

<p>This study evaluated the influence of waterlogging stress on the growth of six (6) accessions (TvSu-1, TvSu-2, TvSu-3, TvSu-4, TvSu-5, and TvSu-10) of <em>Vigna subterranean</em> in a pot experiment. The experiment was setup in a complete block design (CBD) with 3 replicates per treatment. Results of growth parameters of <em>V. subterranean</em> accessions under waterlogging stress, such as plant height, leaf area, petiole length, and number of nodes, were significantly (<em>p </em>= 0.05) decreased when compared to their controls after 8 weeks of planting. For shoot length, TvSu-2 (1.60 ± 0.20 cm) and TvSu-4 (1.60 ± 0.20 cm) recorded the highest values, while TvSu-5 (1.23 ± 0.03) and TvSu-10 (1.23 ± 0.03) had the lowest values, respectively. TvSu-5 (19.03 ± 0.59 cm<sup>2</sup>) and TvSu-10 (19.03 ± 0.59 cm<sup>2</sup>) recorded the highest values in leaf area (LA), while TvSu-3 (14.40 ± 0.51 cm<sup>2</sup>) had the lowest LA. For total photosynthetic pigment (TPP), TvSu-2, TvSu-4, and TvSu-10 had the highest values, with 57.35 ± 1.82 mg/kg, 55.80 ± 2.70 mg/kg, and 55.77 ± 1.90 mg/kg, respectively. TvSu-3 (41.50 ± 8.29 mg/kg) maintained the lowest value. In petiole length, TvSu-5 (15.23 ± 0.33 cm) and TvSu-4 (14.20 ± 0.66cm) had the highest values, while TvSu-3 (8.97 ± 0.33 cm) had the lowest. For the number of nodes, TvSu-2 (15.00 ± 1.76) and TvSu-4 (12.00 ± 1.73) recorded the highest values, while TvSu-10 (10.00 ± 1.00) had the lowest value. Biomass yield analysis of the stressed <em>V. subterranean</em> showed that total fresh weight (TFW), root length (RL), root fresh weight (RFW), shoot fresh weight (SFW), leaf fresh weight (LFW), leaf turgid weight (LTW), total dry weight (TDW), root dry weight (RDW), shoot dry weight (SDW), and leaf dry weight (LDW) of the six accessions were significantly (<em>p </em>= 0.05) decreased when compared to their control. Tvsu-5 had a better biomass yield when compared to other accessions, recording the highest values in SDW (1.62 g), RDW (0.55 g), LFW (0.75 g), SFW (10.31 g), and RL (18.53 ± 0.66). Conclusively, waterlogging stress negatively impacted <em>V. subterranean</em> accessions, but Tvsu-5 had a better waterlogging stress tolerance than other accessions, especially TvSu-3, which was generally poor.</p>