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Maize (Zea mays L. cv. Tau) plants were grown in a calcareous soil for six weeks in pots having separate compartments for growth of roots and vesicular-arbuscular (VA) mycorrhizal fungal hyphae. Soil was sterilized and either left non-inoculated (sterile treatment), or was inoculated with rhizosphere micro-organisms only (MO-VA) or with rhizosphere micro-organisms together with a VA mycorrhizal fungus [Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe (MO + VA)]. Concentrations of Mn in roots and shoots, as well as exchangeable Mn in rhizosphere soil, decreased in the order MO - VA > MO + VA > sterile treatment. In all treatments, the concentration of exchangeable Mn was lower in the rhizosphere soil (0-5 mm distance from the root surface) than in the bulk soil (5-15 or 15-25 mm distance from the root surface). In the rhizosphere soil, the total microbial population was similar in mycorrhizal (MO + VA) and non-mycorrhizal (MO - VA) treatments, but the proportion of Fe- or Mn-reducers was 20- to 30-fold higher in the non-mycorrhizal treatment, suggesting substantial qualitative changes in rhizosphere microbial populations upon root infection with the mycorrhizal fungi. The Mn+IV-reducing potential (net balance between reduction and oxidation) in the rhizosphere soil was also distinctly lower in mycorrhizal treatment compared to non-mycorrhizal treatment. In the sterile treatment, low Mn+IV-reducing potential and correspondingly low concentration of exchangeable Mn in soil, compared to the other treatments, indicates the importance of micro-organisms in Mn reduction in soil and acquisition of Mn by plants. Therefore, the lower Mn concentrations in mycorrhizal plants are most probably caused by a shift in composition and activity of rhizosphere micro-organisms. As a side effect of the treatments, improved soil aggregation, as indicated by soil adhering to the nylon net (facing hyphal compartments) after plant harvest, occurred in non-mycorrhizal and sterile treatments but not in the mycorrhizal treatment. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) was grown in a fertilized calcareous soil in pots which were separated by 30 μm nylon nets into three compartments, a central one for root growth and two outer ones for hyphal growth. The treatments comprised of sterilised soil, either inoculated with rhizosphere microorganisms together with Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe, with rhizosphere microorganisms alone, or non-inoculated (sterile control). In the mycorrhizal treatment concentrations of P and Zn were increased in shoot and roots, as was uptake of P and Zn per unit root dry weight or per unit root length. Copper concentration in roots of mycorrhizal plants, and total uptake and uptake per unit root dry weight or per unit root length of Cu was also increased. The higher acquisition of P, Zn and Cu in the mycorrhizal plants is ascribed to VA mycorrhiza per se (hyphal uptake and translocation to the host). Besides these direct effects, VA mycorrhizal fungi and rhizosphere microorganisms affected the acquisition of other nutrients mostly through alteration of root morphology. In both mycorrhizal and sterile treatments, the decreased concentrations of Ca and Si in the shoot but increased concentrations in the roots seem to be related to restricted apoplasmic solute transport across the endodermal barrier due to decreased number of lateral roots. The concentration of K in both shoot and roots, and Fe in shoot were lower in mycorrhizal plants due to reduced root length. Manganese concentration was also distinctly lower in both shoot and roots in mycorrhizal and sterile treatments, an effect which is attributed to the decrease in Mn reduction in the rhizosphere. Irrespective of nutrient, the uptake per unit root length was higher in mycorrhizal plants, probably due to hyphal contribution and increased supply of nutrients to the root surface by mass flow. Soil analysis indicates hyphal translocation of K but not Mg. [ABSTRACT FROM AUTHOR]

Ocimum tenuiflorum L.f. (syn. O. sanctum L.) (Lamiaceae) is an indigenous ayurvedic medicinal plant of India and is popularly known as holy basil/sacred basil. Oils obtained by hydrodistillation from leaves, stems, inflorescence and whole herb were analyzed by GC and GC/MS and retention indices. Methyl eugenol was the major constituent of all the oils (72.5%, 75.3%, 83.7% and 65.2% in oils from whole herb, leaf, stem and inflorescence, respectively). β-Caryophyllene was the second most dominant constituent and the respective concentration in each oil (5.5%, 6.4%, 2.7% and 12.0%). [ABSTRACT FROM AUTHOR]

A field experiment carried out during 2001--2002 under semi-arid conditions of Hyderabad, India investigated the effect of three different methods of harvesting at full bloom stage, on essential oil yield and quality of methyl eugenol rich sacred/holy basil (Ocimum tenuiflorum L.f.; Lamiaceae). The harvest methods were: harvesting of primary branches, secondary branches and shoot biomass cut at 30 cm above ground level. Four harvests at 102, 192, 287 and 360 days after transplanting of the crop were taken in 1 year in each method of harvest. Harvesting of secondary branches led to maximum plant height and number of secondary branches per plant compared to harvesting of primary branches or shoot biomass cut at 30 cm above ground during second, third and fourth harvests. On the contrary, secondary branch harvest gave least biomass yield in all the four harvests. But due to higher essential oil content, secondary branch harvest gave 25.2 and 15.4% higher total (sum total of all four harvests) essential oil yield (kg/ha per year) over primary branches and shoot biomass cut at 30 cm above ground methods of harvesting, respectively. A similar treatment difference was observed in respect of oil composition studied in the first harvest. Harvesting shoot biomass at 30 cm above ground produced oil containing highest amount of methyl eugenol. The content of methyl eugenol decreased in the order of shoot biomass cut at 30 cm above ground > primary branch > secondary branch treatments. A reverse trend was observed, however, in respect of (E)-cinnamyl acetate, eugenol and beta-elemene constituents of the oil. Little variability was, however, observed among the treatments in respect of 24 other constituents of the oils.

A 1(1/2)-year-old girl with a urogenital sinus defect associated with an enlarged phalluslike clitoris is described. The child had an anteriorly located anus, a single kidney with grade III vesicoureteric reflux, a 3.5-cm-long common urethrovaginal channel, a large vesical calculus, and a hamartoma in the pubic region. After a preliminary colostomy, definitive surgery consisted of urethral reconstruction, vaginal reconstruction using a colonic graft, and posterior relocation of the anus. The discussion centers on a review of the previously reported cases of female pseudohermaphroditism associated with cloacal or urogenital sinus defects (FPHCD). The likely embryogenesis of this condition is discussed, and the similarity of the features with those seen in some patients with complete penoscrotal transposition (CPST) is highlighted., (Copyright 2001 by W.B. Saunders Company.)

A major determinant controlling reactivation of persistent viruses is likely to be the level of cellular factors which regulate virus transcription. Human cytomegalovirus (the largest human herpesvirus) does not replicate in human teratocarcinoma (T2) cells due to a block in transcription of immediate early (IE) gene expression, but these cells become permissive upon retinoic acid induced differentiation. We have analysed changes in DNA binding factors to the major IE promoter/regulatory region of HCMV that occur during differentiation of T2 cells to a permissive phenotype. We show that undifferentiated T2 cells contain a specific nuclear factor that binds to a far upstream region of the major IE regulatory region. Differentiation of T2 cells is associated with a major decrease in this factor and deletion of its specific binding site from IE expression vectors also results in increased levels of expression in undifferentiated cells. Consequently, this novel factor present in undifferentiated cells is a candidate for a differentiation specific negative regulator of HCMV IE gene expression which binds to an element upstream of the major IE enhancer.