Ovules, Female Gametophytes and Embryos are More Sensitive to Heavy Metal Pollution than Anthers and Pollen of Cardaminopsis Arenosa (L.) Hayek (Brassicaceae), A Member of Calamine Flora

Abstract

Reproductive processes including male and female lines, embryo and endosperm development were studied in Cardaminopsis arenosa (syn. Arabidopsis arenosa ) growing on two metalliferous sites (Bukowno and Bolesław, S. Poland), rich in Zn, Pb, Cd and other metals. Disturbances of developmental processes and necroses observed in anthers and ovules influenced plant fertility and seed set of plants from both metal-polluted sites. In anthers, disturbances and necrosis during male meiosis and pollen development occurred at low frequency (4–5%). Pollen grain viability was very high, reaching over 90%. In ovules the frequency of abnormal meiosis, female gametophyte developmental disturbances and necrosis was high, 23.5–28% depending on site. The polluted envi- ronment also affected embryo and endosperm. Necrosis of whole generative structures decreased plant fertility. This study indicates that the range of disturbances and necroses in embryological structures and processes (at gametophyte level) gives a set of useful characters to determine plant tolerance to stress, complementary to many tolerance characters at the sporophyte level of plant ontogenesis.