Reproductive Biology of Angiosperms ביולוגיית ההתרבות של מכוסי הזרע

1. Reproductive Biology of Angiosperms ביולוגיית ההתרבות של מכוסי הזרע פרופ' רבקה דולברגרProf. Rivka Dulberger Britannia room 512, Tel: 03-6409845 e-mail: rivad@post.tau.ac.il 1. Heteromorphic incompatibility In heterostylous plants incompatibility is tightly linked with heteromorphic characters of pollen grains, stigmas, and styles. The aim of my studies is to understand the functional significance of these characters. It appears that some dimorphic characters play a part in pollen-stigma recognition. In distylous species examined the incompatibility response was found to take place at the pollen-stigma interface and it differed in the two morphs. On the other hand, in distylous Villarsia species, the rejection response was observed to occur at the same site within the stigma and at the same stage of pollen-tube development in both morphs. The question asked is whether incompatibility in Villarsia operates independently of dimorphic characters, as is characteristic of monomorphic incompatibility systems. To examine the cytological expression of the rejection response in each morph and to assess the functional significance of floral dimorphisms in these plants, pollen-tube growth is traced both after intraspecific pollinations and after crosses between distylous and monomorphic species. In these examinations cytochemical techniques and light and electron microscopy are used. 2. Changes in the pollen exine after pollinations of Linum species Recent Publications Dulberger, R. and R.Ornduff. 2000. Stigma morphology in distylous and non-heterostylous species of Villarsia (Menyanthaceae). Plant Systematics and Evolution 225: 171--184. Kurek Isaac, Rivka Dulberger, R., Abdussalam Azem, Batsheva Ben Zvi, Duraialagaraja Sudhakar, Paul Christou, and Adina Breiman. 2002. Deletion of the C-terminal 138 amino acids of the wheat FKBP73 abrogates calmodulin binding, dimerization and male fertility in transgenic rice. Plant Molecular Biology 48: 369-381. .