Many plants exude allelochemicals--compounds that affect the growth of neighbouring plants. This study reports further studies of the reported effect of cress (Lepidium sativum) seed(ling) exudates on seedling growth in Amaranthus caudatus and Lactuca sativa. In the presence of live cress seedlings, both species grew longer hypocotyls and shorter roots than cress-free controls. The effects of c...

Two phenomena related to temperature effects have been observed during the induction of betacyanin synthesis by a cytokinin (benzyladenine) in Amaranthus tricolor seedlings. One is a total inhibition of betacyanin accumulation at a temperature (39 C) at which seedling growth is unimpaired, and where there is still adequate uptake of benzyladenine. The other is the apparent induction of a higher...

A trait is robust to a genetic or environmental variable if its variation is weakly correlated with variation in that variable. The source of robustness lies in the fact that the developmental processes that give rise to complex traits are nonlinear. A consequence of this nonlinearity is that not all genes are equally correlated with the trait whose ontogeny they control. Here we explore how de...

The lysis of group A hemolytic streptococci by extracellular enzymes of Streptomyces albus has been studied. The most favorable material for fractionation of the lytic enzymes was obtained by surface growth on shallow layers of liquid medium containing an acid hydrolysate of casein, glucose, and salts. The results of fractionation experiments show that the potent proetolytic enzyme of Streptomy...

A tissue culture procedure is described which permits the quantitative evaluation of the intracellular survival of staphylococci within leucocytes. Staphylococcus aureus survived, but did not multiply, within neutrophils and monocytes of normal rabbits. The same was true of normal human blood leucocytes. Staphylococcus albus on the other hand was destroyed by these cells under the same conditio...

Long-term depression (LTD) of excitatory synaptic transmission has been described in several regions of the brain (Artola and Singer, 1993; Linden, 1994). In most cases, the opposite process, i.e. long-term potentiation (LTP) (Bliss and Collingridge, 1993), is present at the same synapses. Most theories on the functional role of LTD in such neurons assume that LTD acts by resetting synapses tha...

Redroot pigweed is one of the injurious agricultural weeds on a worldwide basis. Understanding of its interference impact in crop field will provide useful information for weed control programs. The effects of redroot pigweed on cotton at densities of 0, 0.125, 0.25, 0.5, 1, 2, 4, and 8 plants m(-1) of row were evaluated in field experiments conducted in 2013 and 2014 at Institute of Cotton Res...

Weed control by crops through growth suppressive root exudates is a promising alternative to herbicides. Buckwheat (Fagopyrum esculentum) is known for its weed suppression and redroot pigweed (Amaranthus retroflexus) control is probably partly due to allelopathic root exudates. This work studies whether other weeds are also suppressed by buckwheat and if the presence of weeds is necessary to in...

The rate of CO(2) reduction in the S-triazine-resistant biotype of smooth pigweed (Amaranthus hybridus L.) was lower at all levels of irradiance than the rate of CO(2) reduction in the susceptible biotype. The intent of this study was to determine whether or not the lower rates of CO(2) reduction are a direct consequence of the same factors which confer triazine resistance. The quantum yield of...

Introduction: In our modern era, life style of human being changes and updates every day that may affect their health status. There is an incredible expectation that natural origin drugs lack undesirable effects not like synthetic drugs, though have the same potency and efficacy. No scientific data is available about the antianxiety properties of Delphinium denudatum root and Amaranthus spinosu...