Comparison of PD withdrawal in upright and inverted ovules. (A) Comparison of PD withdrawal rates for upright and inverted ovules; (B) PD withdrawal of inverted ovules; (C) pollinated PD withdrawal under 100% relative humidity. O, ovule; P, pollen grains; Mi, micropyle. Scale bars = 200 μm.
Jin et al. BMC Plant Biology 2012 12:59 doi:10.1186/1471-2229-12-59