The petal width; sepal, pistil, and stamen lengths; and changes in pollen sizes associated with heterostyly of different morphs in populations of Linum aretioides Boiss. were investigated. Fruit sets were compared in 2 populations and it was investigated whether the Bozdağ population has a heteromorphic incompatibility system. | Turkish Journal of Botany Research Article Turk J Bot (2013) 37: 122-129 © TÜBİTAK doi: Heterostyly in Linum aretioides Aykut GÜVENSEN, Özcan SEÇMEN, Serdar Gökhan ŞENOL* Botany Department, Science Faculty, Ege University, Bornova, İzmir, Turkey Received: Accepted: Published Online: Printed: Abstract: The petal width; sepal, pistil, and stamen lengths; and changes in pollen sizes associated with heterostyly of different morphs in populations of Linum aretioides Boiss. were investigated. Fruit sets were compared in 2 populations and it was investigated whether the Bozdağ population has a heteromorphic incompatibility system. It was observed that the stamen lengths of thrum morphs of Bozdağ were shorter than those of thrum morphs of Babadağ. Pistil lengths of both morphs of Bozdağ were longer than those of morphs of Babadağ. Pollen shapes of both morphs were prolate-spheroidal and subprolate, respectively, in the Bozdağ population and subprolate in the Babadağ population. It was determined that pollen exine in the short-styled and long-styled flowers was dimorphic. The pollen bore a marginal ring of 4 to 8 spinules in the thrum morphs and of 3 to 7 spinules in the pin morphs. It was found that the highest rates of fruit set occurred during cross-hand pollination from pin morphs to thrum morphs and from thrum morphs to pin morphs ( and , respectively). It was shown that in L. aretioides self-pollinations and pollinations between plants of the same morph are incompatible. Key words: Linum, breeding systems, heterostyly, heteromorphic incompatibility 1. Introduction A common associated feature of heterostyly is the presence of a self- and intramorph-incompatibility system that allows only legitimate (between anthers and stigmas of the same level) pollination to set fruit. For a species to be considered heterostylous, the floral morphs must .
