Figure 2.

The rate of ovule abortion is proportional to the duration of salt stress. The number of seeds produced per fruit was plotted as a function of the duration of plant stress. Plants were stressed by supplementing hydroponic solution with either 200 mm NaCl or 400 mm mannitol. Three days after plants were stressed, fruits were dissected and examined using a stereomicroscope. Aborted ovules appeared small and desiccated, while developing ovules remained plump (inset). Even in healthy plants (0 h stress), several ovules failed to develop into seeds. When plants are salt or mannitol stressed, however, many more ovules aborted. Nearly 90% of the ovules aborted if plants were stressed for 12 h or longer. All of the stressed plants, including the ones stressed for 24 h, made a few seeds per fruit. Average fecundity is plotted +mannitol or −NaCl 1 sd.