Fig. 8
From: Proline synthesis in developing microspores is required for pollen development and fertility
Pollen fertility correlates with proline concentration in pollen grains. a Proline content in pollen grains (black bars, left axis) and stage 9/10 anthers (grey bars, right axis) from wildtype (Col-0), p5cs sesquimutants (p5cs) and p5cs sesquimutants carrying either the p35S:P5CS2, the pLtp12:P5CS2m or the p17340:P5CS2 construct. For every analysis an average of 1000 pollen grains or 200 anthers of stage 9–10 were collected and processed. Bars represent the mean ± SE of two (anthers) or three (pollen) independent samples. * and ** indicate significant differences from the corresponding Col-0 wildtype samples (p < 0.05 or p < 0.01, respectively, by student’s T-test). b, c Fertility of p5cs1/p5cs2 double mutant pollen as estimated in Additional file 4: Table S1 in the different complementation lines was correlated either to the amount of proline in pollen grains b or to the amount of proline in anthers at stage 9–10 c. A strong correlation (dotted regression line) was found between proline accumulation in pollen grains and pollen fertility (R2 = 0.98, P < 0.001), while no significant correlation (dotted regression line) was found between proline accumulation in anthers of stage 9–10 and pollen fertility