Five metallic cations (Fe3+, Cr3+, Cal+, Mg2+, Mn2+; concentration range, 1.85 X 10-4 to 37 X 10-4 M) were incorporated individually as chlorides into nutrient broth and agar media used for the recovery of phenol-treated Escherichia coli. The effects observed varied with the concentration and the ionic species. In nutrient agar, Fe3+ and Cr3+ were generally beneficial but were toxic at 37 X 10-...


 This study analyzed the genetic diversity in Coffea canephora genotypes by univariate and multivariate statistical analysis, based on concentrations of macro- micronutrients coffee leaves stages pre-flowering grain filling. The experiment was arranged randomized blocks with three replications, a 42x2 factorial design, which factor one represented evaluated two periods leaf sampling, i.e....

Nutrient availability in ecosystems is patchy both in space and in time. Whereas temporal trends have often been studied, less information exists on spatial patterns of nutrient availability, particularly in aquatic ecosystems. The goals of this study were (1) to describe and quantify patterns of nutrient concentration in surface waters of an arid land stream and (2) to compare spatial patterns...

Soil loss and nutrient concentrations in runoff were evaluated to determine the effects of site preparation burning on a recently harvested loblolly pine (Pinus taeda L.) site in east Texas. Soil and nutrient losses prior to treatment were approximately the same from control plots and pretreatment burn plots. Nutrient analysis of runoff samples indicated that the prescribed burn caused increase...

In a series of experiments with Ricinus communis, abscisic acid (ABA) concentrations in tissues and transport saps, its de novo biosynthesis, long-distance transport, and metabolism (degradation) were affected by nutritional conditions, nitrogen (N) source, and nutrient limitation, or salt stress. In the present study these data were statistically re-evaluated, and new correlations presented th...

Soybean plants (Glycine max L. Merr. var. Hawkeye), grown in nutrient solutions maintained at graded concentrations showed a large response in both shoot dry weight and total ion uptake. Growth rate was dependent upon nutrient concentration, even when quantity of nutrient was not limiting. Peak periods for absorption of specific ions at certain growth stages were not exhibited. Rates of ion upt...

selenium is a non metallic chemical element that affects plant growth and development and but it can due to the presence of antioxidant defense system as a matter of basic human and animal health has been identified. an experiment was conducted to study the effect of se on physiological characteristics and yield of brussels sprouts (brassica oleracea var. gemmifera) with six levels of se (0, 2,...

Sediment loss and nutrient cpncentrations in runoff were evaluated to determine the effects of site preparation burning on a recently harvested loblolly pine (Pinur taeda L.) site in east Texas. Sediment and nutrient losses prior to treatment were approximately the same from control plots and pretreatment burn plots. Nutrient analysis of runoff samples indicated that the prescribed burn caused ...