Nocturne for an unknown pollinator: first description of a night‐flowering orchid (Bulbophyllum nocturnum)

Bulbophyllum nocturnum , a species of section Epicrianthes from New Britain, is described and illustrated. It is the first known example of an orchid species in which the flowers open after dark and close in the morning. The poorly understood pollination biology of section Epicrianthes, a clade with highly unusual flowers, is discussed. Attention is drawn to the close resemblance between the petal appendages of some species and the fruiting bodies of certain Myxogastria. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167 , 344–350.     

Highly syntenic regions in the genomes of soybean, <Emphasis Type="Italic">Medicago truncatula</Emphasis>, and <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis>

Background  

Recent genome sequencing enables mega-base scale comparisons between related genomes. Comparisons between animals, plants, fungi, and bacteria demonstrate extensive synteny tempered by rearrangements. Within the legume plant family, glimpses of synteny have also been observed. Characterizing syntenic relationships in legumes is important in transferring knowledge from model legumes to crops that are important sources of protein, fixed nitrogen, and health-promoting compounds.     

Sucrose Breakdown in Relation to Fruit Growth of Acid Lime (Citrus aurantifolia)

The physiological capacity for sucrose breakdown in developingjuice sac cells of acid limes was estimated by assaying theactivity of the three enzymes of sucrose catabolism in additionto vacuolar acid hydrolysis. The maximum potential rates ofsucrose breakdown were compared with the observed rates of carbonutilization. Highest potential rates of sucrose breakdown (28.621mmol cm^–3 per hydrated active space d^–1) occurredat the initial stages of fruit development where carbon utilizationwas highest. As the fruit developed, the potential rates ofsucrose breakdown and carbon utilization declined to very lowlevels. At 80% of development, vacuolar acid hydrolysis becamethe only physiological mechanism for sucrose breakdown. Therelatively low amounts of sucrose hydrolysed by acid hydrolysisat this time were just sufficient to account for the measuredcarbon demands. The results suggest that carbon supplied bythis distinct sucrose catabolizing system is able to provideadequate levels of carbon skeletons for the observed levelsof respiration and dry weight deposition early in development,but becomes a limiting factor for growth in the later stages. Key words: Vacuolar acid hydrolysis, Citrus aurantifolia