Nearly all bees rely on pollen as the sole protein source for the development of their larvae. The central importance of pollen for the bee life cycle should exert strong selection on their ability to locate the most rewarding sources of pollen. Despite this importance, very few studies have examined the influence of intraspecific variation in pollen rewards on the foraging decisions of bees. P...

Polygala paniculata L. is a medicinal plant that grows in the Brazilian Atlantic coast, known as 'barba-de-São-João', 'barba-de-bode', 'vassourinha branca', and 'mimosa'. In this study, pollen viability was estimated by three different staining methods: 2% acetic orcein, 2% acetic carmine, and Alexander's stain. The young inflorescences of twenty accessions were collected and fixed in a solutio...

Iran is one of the main date (Phoenix dactylifera) producing countries in the world. however, little information is available on the pollen viability and favorable storage conditions of Iranian male date cultivars. This study was conducted to estimate the best in vitro pollen germination of three male date palm cultivars, `Ghanami’, `Samsmavi’ and `Gheibani’ using various doses of boric acid (0...

Pollen germination of Vitis vinifera L., of the family Vitaceae was examined in fresh and stored pollen upto 48 weeks at different temperature i.e., refrigerator (+4C), freezer (-20C, -30C) and freeze drier (-60C). Pollen stored at low temperature showed better germination percentage as compared to pollen stored at +4C and fresh. Freeze dried pollen (-60C) showed the highest germination percent...

Various biotic and abiotic factors are known to exert selection pressures on floral traits, but the influence of ultraviolet-B (UV-B) light on the evolution of flower structure remains relatively unexplored. We have examined the effectiveness of flower structure in blocking radiation and the effects of UV-B on pollen viability in 42 species of alpine plants in the Hengduan Mountains, China. Flo...

The present study, investigated some reproductive and fertility parameters in some wild populations, originating from the North Tunisia (4 populations of Medicago ciliaris and 3 populations of Medicago intertexta). Previous finding revealed that these species are genetically distinct and easily recognized by the number of flowers per inflorescence and pod dimensions. However, biometrical traits...