1. In rice seedlings synthesis of methyl viologen-nitrite reductase was stimulated by light, as was that of NADH-nitrate oxidoreductase (EC 1.6.6.1). A small residual effect of light on the synthesis of the enzymes persisted in the dark for a short time. 2. In etiolated seedlings exposed to light and nitrate, a lag period of 3 h was necessary before enzyme synthesis commenced, whereas in green ...

Plant viruses pose a threat to the acquisition, maintenance and distribution of lupin germplasm (genus Lupinus, family Fabaceae). The availability of sufficient quantities of healthy and virus-free seeds from maintained lupin collections is mandatory for conducting lupin research. The objective of this research was to determine which lupin species were potentially infected with potyviruses (pre...

Azospirillum has been shown to improve coleoptile growth in seedlings growing in darkness under osmotic stress. However, the changes in water relations that may occur in this experimental system have not yet been studied. Two-centimetre long Triticum aestivum cv. Buck Pucará and Triticum durum cv. Balcarceño-INTA seedlings were inoculated with viable or autoclaved (control) Azospirillum brasile...

Enrichment planting within established plantations or secondary forests is a common strategy to enhance forest recovery, given that later successional forest species tend to have low dispersal and limited recruitment into these sites. It is difficult, however, to predict how species of seedlings will perform when planted under different overstory species. The field of phylogenetic ecology offer...

The quantities of endogenous indol-3yl-acetic acid (IAA) in endosperms and scutella of 6-day-old maize seedlings (Zea mays L. cv Giant White Horsetooth) were determined by a fluorimetric method. Endosperms were found to contain 33.4 nanograms IAA per plant, and scutella 7.5 nanograms IAA per plant. [5-(3)H]IAA applied to endosperms of 6-day-old seedlings moved into the roots and radioactivity a...

The effect of temperature on respiration of mitochondria and tissue segments from three wheat (Triticum aestivum L.) and one rye (Secale cereale L.) cultivar grown at 2 and 24 C has been examined. Discontinuities in Arrhenius plots of respiratory activity against temperature were observed for mitochondria and tissue segments from seedlings grown at both temperatures. The rates of respiration de...

To test effects of fertilization on late-season growth and nutrient content of container-grown red pine (Pinus resinosa Ait.), seedlings were subjected to a factorial combination of two fertilization regimes (exponentially increasing concentrations providing 25 (1N) and 75 (3N) mg N seedling(-1), respectively) and two irrigation regimes (well-watered and water-stressed) followed by drought-hard...

A wide range of medicinal plant parts that possess varied medicinal properties are used for extracts as raw drugs. In this study, the ethanolic extract obtained from aerial parts of fennel (Foeniculum vulgare Mill.) seedlings was evaluated in vitro to examine their antimicrobial activity against four Gram-negative and three Gram-positive bacteria and two fungi. Aerial parts of one-month-old see...

BACKGROUND AND AIMS GPT2, a glucose 6-phosphate/phosphate translocator, plays an important role in environmental sensing in mature leaves of Arabidopsis thaliana. Its expression has also been detected in arabidopsis seeds and seedlings. In order to examine the role of this protein early in development, germination and seedling growth were studied. METHODS Germination, greening and establishme...

leaf hydraulic conductance, components of tissue water potential, hydraulic architecture parameters and xylem embolism were examined in greenhouse-grown two-year-old Aleppo pine (Pinus halepensis Mill.) seedlings from six origins representing the geographic range of the species in Italy. Cortical resin composition of the seedlings was also determined. Measurements were made on well-watered seed...