ANALYSIS OF SEQUENTIAL REPRODUCTIVE DEVELOPMENT IN WHITE LUPIN CV LUBLANC

As for other legume crops with sequential flowering, the time-lags bet ween the development of the different pods of white lupin affect the p rogress of intra-plant competition for assimilates, the pattern of see d yield distribution within the canopy, and the whole cycle duration. The objective of this study was to define a convenient indicator descr ibing pod development, and to investigate the relationship between the plant vegetative architecture and the progression of the reproductive stages along the different inflorescence types. 'Lublanc' spring whit e lupin was grown in the glasshouse during 1 year and in the field dur ing 4 years, with various sowing dates and plant densities. Current ma nagement techniques, including irrigation, were applied. The progress of seed water content allowed distinction of the period when seed abor tion occurs from the seed filling phase. The progression rate of flowe ring up the racemes was related to the growth rate of the considered a xes at the beginning of their flowering. The flowering delay between 2 successive orders of axes depended on both the leaf number on the bra nches and the individual branch growth rate during their elongation. T he time of the reproductive stages at a pod position depended only on the time of flowering at that position. The duration of the seed filli ng phase did not vary among pod positions.