Fig 1.
Pictures illustrating the dissected compartments.
A representative fresh cross section of the grain (150°DAA) showing the main different tissues (A): endosperm is composed of testa + aleurone layer + endosperm s.s. The three main steps of the grain dissection allowing the collection of the three main compartments of interest (B-D).
Table 1.
Final masses and dimensions of basal mature grains from the central spikelets of wheat plants exposed to heat shocks.
Fig 2.
Effects of heat shocks on whole grain dimensions.
Whole grain fresh mass (A), volume (B), dry mass (C), water mass (D), length (E) and width (F) during grain development after anthesis. Heat shocks (HS) were applied during the lag-phase (HS1), during the grain filling-phase (HS2) or during both the lag-phase and filling-phase (HS12) of the grain development, compared to Control. Each point corresponds to the mean of measurements on 10 basal grains from central spikelets sampled on 5 spikes. Lines represent the growth functions fitted to the observed values. Growth functions were selected on the base of the growth curves obtained for all treatments pooled (S2 Table). Vertical grey bars indicate the times and duration of exposure to heat shocks (~90°Cd and ~420°Cd after anthesis for respectively HS1 and HS2 during 4 days (~95°Cd).
Fig 3.
Effects of heat shocks on whole grain growth rates.
Whole grain fresh mass accumulation rate (A), volume growth rate (B), dry mass accumulation rate (C), and width growth rate (D) during grain development after anthesis. Heat shocks (HS) were applied during the lag-phase (HS1), during the grain filling-phase (HS2) or during both the lag-phase and filling-phase (HS12) of the grain development, compared to Control. Each point corresponds to the values estimated from the derivative of the fitted growth functions (S2 Table). Vertical grey bars indicate the times and duration of exposure to heat shocks (~90°Cd and ~420°Cd after anthesis for respectively HS1 and HS2 during 4 days (~95°Cd).
Table 2.
Estimated maximum values of the various traits of basal grains from the central spikelets of wheat plants exposed to heat shocks.
Table 3.
Estimated rate of growth of basal grains from the central spikelets of wheat plants exposed to heat shocks.
Table 4.
Estimated duration of growth of basal grains from the central spikelets of wheat plants exposed to heat shocks.
Fig 4.
Effects of heat shocks on OLs growth.
OLs fresh mass accumulation (A,B), dry mass accumulation (C,D) during grain development after anthesis. Each point on A or C graphs corresponds to the mean of measurements on 10 basal grains from central spikelets sampled on 5 spikes. Curves on graphs B and D represent the fitted growth functions (Gompertz with maxima) to the observed values of OLs fresh mass (B) or dry mass (D). Heat shocks (HS) were applied during the lag-phase (HS1), during the grain filling-phase (HS2) or during both the lag-phase and filling-phase (HS12) of the grain development, compared to Control. Vertical grey bars indicate the times and duration of exposure toheat shocks.
Fig 5.
Effects on heat shocks on endosperm cell number.
Heat shocks (HS) were applied during the lag-phase (HS1), during the grain filling-phase (HS2) or during both the lag-phase and filling-phase (HS12) of the grain development, compared to Control. Each point corresponds to cell counting in one grain (n = 5 per each sampling date). Curves correspond to the growth function (Gompertz with maxima) fitted to the observed values over time after anthesis. Vertical grey bars indicate the times and duration of exposure to heat shocks (~90°Cd and ~420°Cd after anthesis for respectively HS1 and HS2 during 4 days (~95°Cd).
Table 5.
Masses and dimensions of basal grains from the central spikelets at the end of the lag-phase.
Table 6.
Fresh and dry masses and volumes of the endosperm and OLs at the end of the lag-phase.
Table 7.
Duration, expressed in °Cd, of the different phases of the grain development for each heat shock treatment.