Abstract

Late season crops in planossoil are prone to waterlogging associated with high temperatures that are characteristic of the season, during brief periods of time in early summer. The aim of the present study was to evaluate growth, assimilate partitioning and seed vigor of bean plants subjected to periods of waterlogging and high temperatures during late season. Bean plants of the IPR Tuiuiú genotype were submitted to conditions of soil field capacity and to waterlogging for 8, 16 and 24 h. In order to obtain growth data, plants were collected in regular intervals of seven days until the end of the crop cycle, starting after sowing, dry matter content and leaf area were determined and used to estimate dry matter production, relative growth and net assimilation rates, leaf area index, solar energy conversion efficiency and organs’ dry matter partitioning. Seeds were collected at the end of the developmental cycle and used for seedling emergence test and evaluation of initial growth. The level of stress imposed by waterlogging and high temperatures is time dependent, paralyzing dry matter allocation in bean plants and reducing the conversion efficiency of solar energy. Seeds produced by plants under this stress present low vigor and reduced initial growth.

Key words: Phaseolus vulgaris L., stress, dry matter, physiological performance of seed.