Title : Post-zygotic self-incompatibility in kigelia pinnata (Jacq.) DC. (Bignoniaceae)
Abstract:
Results of previous work carried out on breeding system of Kigelia pinnata were indicative of its being late- acting self-incompatible. However, the authenticity of this statement remained to be ascertained. Incidence of this phenomenon was, therefore, investigated in detail by subjecting the flowers to different pollination treatments. This involved the tracking of pollen tube pathway using fluorescence microscopy, observing serial sections of ovules in both self- as well as cross-pollinated pistils and scoring the fruit set so obtained. Many interesting facts have come to the fore. Only cross-pollinated pistils lead to fruit formation. Repeated experiments with self and cross pollen yielded similar results; 100% fruit set in manual cross pollinations and nil in manual selfing. Microscopic observations revealed good pollen germination and successful growth of self-pollen tubes throughout the entire length of pistil upto the ovary, and then their penetration into majority of ovules. However, the rates of development to further stages were considerably slower in selfed pistils which stopped completely after some initial divisions. Surprisingly, no other signs of malfunctioning were detected indicating a sudden arrest of cell division. This was followed by the abscission of such pistils 6-7d post-pollination. All these features in comparison with those of cross- pollinated pistils will be highlighted in the presentation.
Audience Take Away:
- The present work would fill the gap and add to the knowledge about late acting self- incompatibility in flowering plants.
- Different embryological aspects are quite informative particularly the diagrams which could help in making students better understand the concepts.
