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.