NodulesData2025

Field pea plants were grown in winter (July to August) and spring (October to November) of 2023, outdoor under a rain-out shelter at the National University of Entre Ríos, Oro Verde, Argentina (31°49'50.0"S 60°31'14.6"W). Spring type, yellow-seed field pea cv Reussite was inoculated with Rhizobium leguminosarum biovar viceae (Rizobacter, Argentina) at 4 ml per kg seed and treated with systemic fungicide (Fludioxonil 2.5 g, Metalaxil-M 2.0 g and Tiabendazol 15 g) at 1 ml per kg seed. Starting N-NO3- content of the soil was 70.8 mg N kg⁻¹ soil in winter and 30.3 mg N kg⁻¹ soil in spring.
Seeds were sown in 5-l pots filled with a mixture of local top-soil Acquic and Vertic Argiudoll of the Asociación Oro Verde serie (Plan Mapa de Suelos, 1998, Soil Survey Staff, 2014). Upper and lower limits of water holding capacity were assessed in a soil sample (Wilson et al., 2013).
Water regimes were established targeting three levels of plant available water (PAW) in soil: 60%, 85%, and 100%; the premise is that 60 % PAW would cause drought stress, 100 % PAW may cause hypoxia stress but not anoxia, and 85 % PAW would allow for potential plant growth (Sadras and Milroy, 1996). At the V3 stage, treatments were initiated adjusting irrigation with a programmed controller (Rain Bird ESP-RZXe, USA). Irrigation frequencies were periodically monitored gravimetrically to keep actual soil moisture at ±5% of the target treatments. Water treatments were allocated to a completely randomized design with four replicates and each replicate consisted of two plants per pot.