Abstract

In Poland, Fritillaria meleagris is critically endangered plant with only 2 natural populations noted. The studies on nectar secretion and pollination in F. meleagris were conducted in 2006–2010, in nature reserve ‘Szachownica w Krównikach’, SE Poland, on an area of approx. 20 ha. In this reserve, Fritillary plants emerge flowers about middle April and bloom for the next 7–8 days. Nectar is secreted in perigonal nectaries located adaxially, at the base each of six tepals. They have a form of groove 10– 12 mm long and 2–3 mm wide. The nectary is composed of one layer of secretory epithelial cells and 2–3 layers of subsecretory parenchyma. It is supplied with several vascular bundless. Cell walls of the nectary develop prominent ingrowths concomitantly with secretory activity, and in the cytoplasm numerous secretory vesicles are present. Traces of secretion appears one day before flower opening and nectar is secreted until the end of anthesis. Maximum amount of nectar secreted (29.9 mg, on average) was noted in the stage of full anthesis, and also at this stage stigma showed the strongest receptivity. Concentration of nectar ranged between 25.2% just after flower opening to 70% at the maximum stage of anthesis. The nectar is composed of glucose, fructose and sucrose in almost equal proportions, and it is reach in amino-acids. The difference in volume and concentration of nectar secreted in the nectaries located on the tepals of outer and inner whorl was insignificant. The flowers are important source of pollen and nectar for local bumblebee queens that are key pollinators of F. meleagris.