Pollination systems frequently reflect adaptations to particular groups of pollinators. Such systems are indicative of evolutionary specialization and have been important in angiosperm diversification. We studied the evolution of pollination systems in the large genus Ruellia. Phylogenetic analyses, morphological ordinations, ancestral state reconstructions, and a character mapping simulation w...

Considerable infonnation has been developed on floral induction and the flowering process in Citrus in the papers which precede this one. Flower induction is a prerequisite to fruit production, so it is very important to have a clear understanding ofthe process. However, simply producing large numbers offlowers does not necessarily guarantee a subsequent large crop of fruit to harvest when they...

Most flowering plants depend on animal vectors for pollination and seed dispersal. Differential pollinator preferences lead to premating isolation and thus reduced gene flow between interbreeding plant populations. Sets of floral traits, adapted to attract specific pollinator guilds, are called pollination syndromes. Shifts in pollination syndromes have occurred surprisingly frequently, conside...

• Ecological generalization is postulated to be the rule in plant-pollinator interactions; however, the evolution of generalized flowers from specialized ancestors has rarely been demonstrated. This study examines the evolution of pollination and breeding systems in the tribe Gesnerieae (Gesneriaceae), an Antillean plant radiation that includes specialized and generalized species. • Phylogeneti...

the germination power of orchids (orchidaceae family) seems to betoo weak due lack of albumen. the study carried out with various treatments including pollination time and ga3 for breaking dormancy and increasing seed germination of orchids. the effect of pollination time (8 periods from january to august) and gibberellic acid (0, 500, 1000 and 1500 mg l-1) were studied on germination of phalae...

Starch gelatinization and retrogradation properties of corn were studied to determine the effect of controlled (self) pollination versus noncontrolled pollination on analytical determinations, and the potential to eliminate the expensive and time-consuming step of self-pollinating before research screening of corn genotypes. Twenty-four hybrids were grown in two Iowa locations, Story City and A...

Pollination regulates a syndrome of developmental responses that contributes to successful sexual reproduction in higher plants. Pollination-regulated developmental events collectively prepare the flower for fertilization and embryogenesis while bringing about the loss of floral organs that have completed their function in pollen dispersal and reception. Components of this process include chang...

to evaluate the effects of presence of insect pollinators on quantity and quality of seeds of two common cultivars of onion (allium cepa l.), namely red azar shahr and yellow sweet spanish, an experiment in a factorial randomized complete block design was carried out at two sites. bulbs of equal size were planted with plant to plant 35 cm and row to row 50 cm spacing. at each site, experimental...