Post‐flowering Biomass and Nitrogen Accumulation of Lentil Substantially Contributes to Pod Production

ABSTRACT Lentil (Len culinaris L.) is an indeterminate legume crop that continues to grow and accumulate biomass (DM) after flowering. Abundant N can stimulate post‐flowering vegetative growth of lentil and reduce partitioning of DM and N into pods. The effect of inoculant rhizobia, 50 kg N fertilizer ha–1 and non‐treated control treatments on DM and N partitioning of lentil was studied in Saskatchewan. Accumulated DM and N in leaf, stem and pod of eight lentil cultivars were measured at flowering, podding, and maturity. The results showed that more than 85% of DM (5.8 g DM plant–1) and N (143 mg N plant–1) were accumulated after lentil flowering. Of the 167 mg N and 6.5 g DM plant–1 at maturity, 58% DM and 75% N was in pod, 26% DM and 10% N was in stem, and leaf had the remaining 15% of the DM and N. The treatments affected N concentration and occasionally total DM and N content of the plant organs, but partitioning of DM and N among the three parts was independent of the treatments. In comparison, soil moisture significantly affected total and partitioning of DM and N into pod. Among the cultivars, the medium‐maturing cultivar CDC Milestone accumulated similar DM and N as late‐maturing ones, but allocated a greater portion of DM and N to pod than the late‐maturing cultivars. Overall, available N during pod‐filling promotes lentil biomass and pod production, but the efficiency of DM and N partitioning to pod is controlled by plant genotype and soil moisture.