Experimental and observational studies of the submersed, freshwater macrophyte Vallisneria americana Michx. revealed that depth, wind and wave exposure, and current velocity may all influence fruit set. In this dioecious species, long-pedunculate female flowers are pollinated by free-floating male flowers at the water surface. Average fruit set in the natural populations studied varied from zero to 97% of the flowers observed. With increasing water depth in New York and Pennsylvania lakes, female plants continued to flower, though these flowers were unable to reach the surface, and consequently, did not set fruit. Fruit set was also lower in relatively open sites exposed to wind and waves, presumably because male flowers do not remain in the vicinity of female flowers long enough for effective pollination. This was particularly striking at a site with low male flower densities, but fruit set was increased to 100% at that site by confining the floating male flowers within a field enclosure. In a river, fruit set was negatively correlated with surface current velocity, and was reduced to zero in current velocities greater than 0.30 m · s. Fruit set in V. americana appears to be restricted or precluded by physical environmental conditions in a variety of sites.
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http://dx.doi.org/10.1007/BF00334653 | DOI Listing |
BMC Plant Biol
January 2025
School of Engineering, Dali University, Dali, Yunnan Province, China.
The homeotic transformation of stamens into pistil-like structures (pistillody) causes cytoplasmic male sterility (CMS). This phenomenon is widely present in plants, and might be induced by intracellular communication (mitochondrial retrograde signaling), but its systemic regulating mechanism is still unclear. In this study, morphological observation showed that the stamens transformed into pistil-like structures, leading to flat and dehiscent pistils, and fruit set decrease in sua-CMS (MS K326, somatic fusion between Nicotiana.
View Article and Find Full Text PDFAm J Clin Nutr
January 2025
Freemasons Centre for Male Health & Wellbeing, School of Medicine, University of Adelaide, Adelaide, South Australia, Australia.
Background: High prevalence of urinary tract infections (UTI), including cystitis, and concern for antimicrobial resistance justify safe and effective non-antibiotic therapies for prevention of recurrent UTI (rUTI). This study investigated the effect of a whole cranberry fruit powder supplement on incidence of culture-confirmed UTI (primary outcome) in females with rUTI history.
Methods: This multicenter, 6-month, randomized, placebo-controlled, double-blind study enrolled 150 healthy females (18-65 years, body mass index (BMI) >17.
Plants (Basel)
January 2025
Department of Agricultural, Food and Environmental Sciences, Università Politecnica delle Marche (UNIVPM), Via Brecce Bianche 10, 60131 Ancona, Italy.
Water scarcity is an ecological issue affecting over 10% of Europe. It is intensified by rising temperatures, leading to greater evaporation and reduced precipitation. Agriculture has been confirmed as the sector accounting for the highest water consumption globally, and it faces significant challenges relating to drought, impacting crop yields and food security.
View Article and Find Full Text PDFPlants (Basel)
January 2025
Institute for Environmental Studies, Faculty of Science, Charles University, Benátská 2, 12900 Prague, Czech Republic.
Species are disappearing worldwide, and changes in climate and land use are commonly assumed to be the most important causes. Organisms are counteracting the negative effects of environmental factors on their survival by evolving various defence strategies, which positively affect their fitness. Here, the question addressed is: can evolution shape these defence strategies so that they positively affect the fitness of an organism? This question is complex and depends on the taxa and environmental factors.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Department of Food Measurement and Process Control, Institute of Food Science and Technology, Hungarian University of Agriculture and Life Sciences (MATE), Somlói út 14-16., H-1118 Budapest, Hungary.
The processing of beans begins with a particularly time-consuming procedure, the hydration of the seeds. Ultrasonic treatment (US) represents a potential environmentally friendly method for process acceleration, while near-infrared spectroscopy (NIR) is a proposedly suitable non-invasive monitoring tool to assess compositional changes. Our aim was to examine the hydration process of red kidney beans of varying sizes and origins.
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