Time of Flowering of Pea (Pisum sativum L.) as a Function of Leaf Appearance Rate and Node of First Flower

In order to assess the influence of environmental conditions on time of flowering of pea (Pisum sativum L.), a serial sowing trial was conducted over 2 years at Dijon, France, on two winter cultivars Frisson and Frilene. Time of flowering was analysed according to two variables: the leaf appearance rate RL and the node of first flower NI. RL was linearly related to temperature (r2 = 0·94). The base temperature was 2°C for both varieties. Growth rate accounted for the residual variability of RL . Photoperiod and temperature acted on NI in an additive way. Frilene, the later genotype, was more responsive than Frisson. A model for predicting time of flowering based upon these results is proposed. Deviations from this model were related to N nutrition in interaction with the plant water relations. Steps for improving the model are then discussed.