ACTA AGROBOTANICA Vol. 63 (2): 25–32 2010 THE STRUCTURE OF SOME FLORAL ELEMENTS AND THE NECTAR PRODUCTION RATE OF Polemonium caeruleum L. Mirosława Chwil Department of Botany, University of Life Sciences in Lublin, Akademicka 15, 20-934 Lublin, Poland e-mail:
[email protected] Received: 12.07.2010 Abstract Its generic name comes from the name of the mythi- The present study, carried out in the period 2008 – 2009, cal king of Pontus, Polemon, while the second compo- covered some morphological and anatomical features of the flo- nent of its name is derived from the word caelum that wers of Polemonium caeruleum L. and their nectar production means “heaven”, probably due to the blue colour of the rate in the climatic conditions of the Lublin region. Observa- corolla (R e jewski, 1996). tions were made with stereoscopic, light and scanning electron Polemonium caeruleum is a rhizomatous per- microscopy. Nectar production in the flowers was determined ennial with an erect stem growing up to a height of using the pipette method. 120 cm. It flowers from June to August. Its blue flow- The flowers of Polemonium caeruleum develop a ca- ers with a diameter of 3 cm are borne on short pedi- lyx covered by an epidermis with numerous non-glandular and cles and clustered in an apical panicle composed of glandular trichomes. The secretory trichomes are composed of cymes (Rutkowski, 2008; Witkowska-Ż uk, a several-celled stalk and a four-celled head. At the bounda- ry of the corolla tube and the lobes, there is white colouration 2008).