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A field experiment was carried out during the rainy (kharif) season of 2001 at the experimental farm of the Indian Agricultural Research Institute, New Delhi, India, to study the effect of date of transplanting and nitrogen on yield attributes, yields, nutrient accumulation and nitrogen use efficiencies in hybrid and non-hybrid aromatic rice. The experiment consisted of 9 treatments with 2 varieties (Pusa Basmati 1 and Pusa Rice Hybrid 10), 3 transplanting dates (3, 10 and 17 July, 2001) and 4 nitrogen levels (0, 60, 120 and 180 kg N ha-1). Pusa Rice Hybrid 10 had significantly higher values of yield attributes (panicles hill-1, panicle weight, spikelets panicle-1, filled grains panicle-1, 1000-grain weight), yields and nutrient accumulation than the non-hybrid Pusa Basmati 1. There were significant reductions in yield attributes, yields and nutrient accumulation after delayed transplanting. Timely transplanting on 3 July led to 8.4 and 19.1% higher grain yield than transplanting on 10 and 17 July, respectively. Successive nitrogen levels had a significant effect on yield attributes (except 1000-grain weight), yields and nutrient accumulation up to 120 kg N ha-1. The maximum grain yield (5.87 t ha-1) was recorded at the highest level of N nutrition (180 kg Nha-1) and was 4.2, 15.5 and 39.3% higher than in the 120 kg, 60 kg N ha-1 and control treatments, respectively. Pusa Rice Hybrid 10 also had significantly higher values of agronomic nitrogen use efficiency (ANUE) (12.5 kg grain kg-1 N applied), apparent nitrogen recovery (27.4%), physiological NUE (44.2 kg grain kg-1 N uptake), N harvest index (62.7%), N efficiency ratio (119.6 kg dry matter kg-1 N uptake) and physiological efficiency index of nitrogen (47.4 kg grain kg-1 N uptake) than non-hybrid Pusa Basmati 1.

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Abstract  

A very sensitive spectrophotometric method for analysis of thorium based on thoriumbenzoate-aniline blue complex is described. The maximum absorbance is found to be at 660 nm. The molar absorptivity of the complex is 3.16 103 1 mol−1-cm−1. The interference due to many ions was found to be within acceptable limits. This method has been used to determine the quantity of thorium from a synthetic solution.

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Abstract  

The general method of evaluating the temperature integral for temperature dependent frequency factors have been considered. The values of the temperature integral as evaluated by the present method are in excellent agreement with those obtained numerically.

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The outcome of various solvent extraction (water, methanol, acidic 50% methanol, 70% acetone, acidic 50% methanol followed by 70% acetone) on the total phenolic content (TPC) and antioxidant capacity of fruit pulp, seeds, leaves and stem bark of seabuckthorn (Hippophae rhamnoides L.) was investigated. The seabuckthorn extracts possess high phenolic content, 1666–13769 mg GAE/100 g d.w. The mean TPC was found highest in seeds (11148) followed by stem bark (10469), leaves (6330) and pulp (3579 mg GAE/100 g d.w.). In general, the 70% acetone and acidic 50% methanol followed by 70% acetone extracts was found to contain significantly higher TPC than those obtained in other extracting solvents. Antioxidant capacity in terms of IC50 value of pulp (3.39 mg ml−1) was up to 7.8 times higher than those reported for stem bark (0.43 mg ml−1) and up to 2.4 times higher than those found in seeds (1.4 mg ml−1). Further, antioxidant capacity by FRAP assay showed that the stem bark possess maximum antioxidant capacity (16.83) followed by seeds (15.26), leaves (12.73) and pulp (12.61), all as mM FeSO4. Significant correlation was found between TPC and antioxidant capacity by DPPH and FRAP assays.

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Mango malformation is one of the most important diseases limiting its cultivation. However, disease resistance is known in some mango cultivars and is a desirable trait that can be utilized for developing mango varieties resistant to malformation. Resistance genes cloned from different plant species have revealed several similarities in DNA sequence and structural motifs. This provides the possibility of isolating resistance genes by polymerase chain reaction (PCR) with degenerate oligonucleotide primers designed from highly conserved regions of the nucleotide binding site (NBS). In the present study, we used eight combinations of oligonucleotide primers designed on the basis of P-loop and hydrophobic domains of conserved NBS-leucine rich repeat (LRR) protein sequences for amplifying resistance gene analogues (RGAs) in eight mango cultivars and hybrids showing a variable degree of resistance to mango malformation disease. A single band of about 500 bp in all mango cultivars was obtained from the s2+as2 primer combination. RGAs isolated from mango showed 73% similarity with RGAs in databases. It confirms that RGAs were actually isolated from mango. The obtained sequence can be used for isolating full length R-genes.

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The free and agar immobilized cells of Nocardia globerula NHB-2 having nitrilase (EC 3.5.5.1) activity were used to catalyse the transformation of benzonitrile to benzoic acid. The whole cells of N. globerula NHB-2 were immobilized in agar which exhibited maximum conversion of benzonitrile to benzoic acid in 0.1 M potassium phosphate buffer pH 7.5 (free cells) 8.0 (immobilized cells), temperature 40 °C, cells 2 mg dcm ml −1 reaction mixture and benzonitrile (4% v/v) in 4 h (free cells). The effect of temperature on the stability of nitrilase was studied and cells retained 100% activity at 30 °C and lost 50% activity at 40 °C. In a fed batch mode of reaction 108 and 84 gl −1 benzoic acid was produced using free and agar entrapped cells (2 g dcm). The agar immobilized cells were recycled up to three times and 80, 62, 20 gl −1 benzoic acid was again produced respectively in each of three cycles and a total 244 g benzoic acid was produced by recycling the same mass of immobilized biocatalyst.

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Field trials were conducted in the dry and wet seasons of 1998 at Samaru (11°11' N, 07° 38' E, 686 m above sea level) in the northern Guinea savanna of Nigeria, to investigate the potential of cinosulfuron and CGA152005 seed treatments on the reaction of upland rice varieties to Striga hermonthica (Del.) Benth. Seven varieties of upland rice formed the main plots treatments while four levels each of cinosulfuron at 0.1, 0.2, 0.4 and 0.6 g/l and CGA152005 at 0.008, 0.016, 0.032 and 0.064 g/l, as well as two no herbicide treatments of dry sowing and distilled water-soaked planting were assigned to the subplots. The experiment was laid out in a split plot design and replicated three times. The resistant varieties FARO 40 and WAB 56-50 did not support Striga emergence and also produced grain yields which were the maximum, or comparable to the maximum. FARO 11, a susceptible variety, produced high grain yields in spite of support for early, high Striga emergence. In spite of delayed emergence of Striga on FARO 38 and FARO 48, these varieties, as well as FARO 46 and FARO 45, supported high Striga emergence, exhibited high crop reaction scores to Striga and produced low grain yields. The seed treatment of upland rice varieties with cinosulfuron at 0.2 to 0.6 g/l and CGA152005 at 0.032 and 0.064 g/l significantly delayed Striga emergence compared with the lower rates. After seed treatment with cinosulfuron at 0.6 g/l, the susceptible rice variety FARO 38 and the resistant variety WAB 56-50 produced rice grain yields comparable to the maximum obtained with FARO 40 given seed treatment with CGA 152005 at 0.064 g/l. The significant interactions of varieties of upland rice and herbicide seed treatments on the number of days to first Striga emergence, Striga shoot count and crop reaction to Striga confirm the differential influence of various concentrations of the herbicide seed treatments on the virulence of Striga hermonthica on varieties of upland rice.

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Four species of Lejeunea viz., L. discreta, L. kashyapii, L. mehrana and L. parva are reported here for the first time from Meghalaya. Of which, Lejeunea kashyapii and L. mehrana are endemic, earlier reported from Sikkim only. The taxonomic description and illustrations of all are provided in present communication.

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The alternative system of medicines like Unani and Ayurveda is preferred worldwide nowadays due to its therapeutic efficacy, lower side effects, holistic approach, psychological dimensions, and qualitative action of weather and seasonal requirement. A simple procedure is described for the simultaneous extraction and estimation of piperlongumine and piperine in a well-known Unani polyherbal formulation using reversed-phase high-performance liquid chromatography (HPLC). The chromatography was carried out on reversed-phase C18 (250 × 4.6 mm) column with a mobile phase containing acetonitrile—water (50:50 v/v). Detection was accomplished with ultraviolet (UV) detection at λ = 325 nm. The flow rate was kept as 1.0 mL−1. The proposed method was validated according to International Conference on Harmonization (ICH) guidelines for accuracy (94.4–105.0%), precision (0.37–2.17% RSD), and robustness (0.14–2.11% RSD). The limit of detection (LOD) values were found as 30 and 10 ng mL−1, while limit of quantification (LOQ) was 100 and 30 ng mL−1 for piperlongumine and piperine, respectively, which proved the sensitivity of the method satisfactory enough for accurate analysis of the both piperlongumine and piperine.

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Summary

A validated reversed-phase HPLC method has been developed for quantitative analysis of berberine in Berberis aristata fruits and in a polyherbal formulation. Separation of berberine was achieved on a C18 column with a mobile phase consisting of a 10–80% acetonitrile gradient in 0.05% aqueous orthophosphoric acid. The flow rate was 1 mL min−1. Detection was at 266 nm. A sharp, well defined peak was obtained at a retention time of 10.0 ± 0.4 min. The method was validated in accordance with ICH guidelines for accuracy, precision, robustness, and the limits of detection (LOD) and quantification (LOQ). Results from linear regression analysis were indicative of a good linear relationship (r 2 = 0.998 ± 0.0011) in a wide concentration range (5–500 μ g mL−1). LOD and LOQ were 1.5 and 5.3 μg mL−1, respectively. Satisfactory recovery results (94.6–103.1%) were obtained by the method of standard addition. Intra-day, inter-day, and intersystem precision was satisfactory, with relative standard deviation in the range 0.7–1.8%. The berberine content of fruit of Berberis aristata and the herbal formulation were 0.033% and 0.0089% (w/w), respectively. This HPLC method for quantification of berberine can be used for quality control and standardization of several crude drugs and different herbal formulations in which berberine is present as a phyto constituent.

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