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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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A field experiment was carried out during the rainy season (June-October) of 1998 at the Research Farm of the Indian Agricultural Research Institute, New Delhi, India to study the effect of coating prilled urea with eco-friendly neem (Azadirachta indica A. Juss.) formulations in improving the efficiency of nitrogen use in hybrid rice. The experiment was laid out in a split-plot design with three replications. Two rice cultivars, hybrid rice (NDHR-3) and Pusa Basmati-1, formed the main plots, with the levels of nitrogen (0, 60, 120 and 180 kg N ha-1) and various forms of urea at 120 kg N ha-1 in the sub-plots. The results obtained in this study showed that the rice hybrid NDHR-3 performed significantly better than the scented variety Pusa Basmati-1 for almost all the agronomic traits tested (growth, yield attributes, grain and straw yields, nitrogen uptake and apparent N recovery) The advantage of grain yield in hybrid NDHR-3 was nearly 16 q/ha over Pusa Basmati-1. Increasing levels of nitrogen significantly increased the number of effective tillers hill-1, panicle length, panicle weight, grain and straw yields and nitrogen uptake, thereby revealing a significant decline in agronomic nitrogen use efficiency (NUE). Among the sources of N, Pusa Neem Golden Urea proved to be significantly superior to other sources with regards to panicle length, grain yield, N uptake, agronomic nitrogen use efficiency and apparent N recovery (%), indicating that coating urea with neem formulations not only increased the grain yield, NUE and apparent N recovery, but also helped to reduce the environmental hazards associated with the use of large amounts of urea.

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Abstract  

Earlier researchers like Turkeli, suggested that ‘the factors which determine the productivity of scientists are admittedly complex and perhaps not amenable to real scientific analysis′. The present investigation was designed with the sole purpose of confronting such a complex problem. Nearly 200 variables influencing research productivity were collected through relevant literature, analysis of biographies of great scientists, and discussion with eminent scientists. Finally, through a critical examination, 80 variables were selected for the use of Q-sort technique. The sample for the study consisted of a cross section of scientists ranging from Fellows of Indian National Science Academy to young agricultural scientists. Mailed questionnaires and personal interview methods were used for collecting data. Out of a total of 912 respondents, reply was obtained from 325. On the basis of Q-sorted data, 26 variables were selected for further analysis and they were subjected to principal component factor analysis. The results indicated eleven factors affecting research productivity of scientists. They were: persistence, resource adequacy, access to literature, initiative, intelligence, creativity, learning capability, stimulative leadership, concern for advancement, external orientation, and professional commitment.

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In the present study on the self-incompatibility in inbred lines of ten local Indian cultivars (Pusa Chetki, Chetki Long, Aushi, Alipur Local White, Jaunpuri, Half Red, Scarlet Red, Chinese Pink, Desi Red and Khasi Kata) of radish ( Raphanus sativus L.), Pusa Chetki, Chetki Long, Aushi, Alipur Local White and Jaunpuri were classed as selfcompatible, Half Red, Scarlet Red and Chinese Pink as intermediate and Desi Red and Khasi Kata as self-incompatible. The highest number of germinated pollen grains and pollen tubes was observed in Pusa Chetki, followed by Alipur Local White, Jaunpuri, Aushi and Chetki Long. The discrepancy in the number of germinated pollen grains in the stigmas may be explained by the inhibitory action of large numbers of self-incompatible pollen grains on the stigma. When two lines, Desi Red and Khasi Kata, were grown under different temperature and photoperiod conditions, no breakdown in self-incompatibility was observed, and the flowering periods of these lines are naturally well synchronized. It is well known that uniform and effective cross-pollination may be of great importance for obtaining a high quantity of hybrid seed in self-incompatible types. To produce single cross hybrid seed, the inbred lines Desi Red and Khasi Kata can be used as parental lines.

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The role of blue green algal (BGA) biofertilizers has been limited to its relevance and utilization in rice crops, and scanty information is available on their use in conjunction with organic amendments and their influence on wheat (Triticum aestivum) . An experiment was conducted from November 2003 to April 2004 in the fields of the Indian Agricultural Research Institute (IARI), New Delhi, India to evaluate the effect of vermicompost, farmyard manure and biofertilizers (BGA and Azotobacter ) in different combinations with chemical fertilizers (N 40 P 30 K 30 ) in wheat (var. HD 2687). Selected soil biological parameters (cyanobacterial diversity/abundance, nitrogenase activity and the phototrophic biomass of soil cores) were measured. The application of vermicompost in combination with BGA biofertilizer (B+V+N 40 P 30 K 30 ) brought about a significant increase in nitrogenase activity (from 0.1 in N 80 P 30 K 30 to 2.0 nmoles mg chl −1 h −1 ), while Azotobacter + BGA (+N 40 P 30 K 30 ) treatment gave the highest values of chlorophyll (1.19 μg g −1 soil). The addition of vermicompost and farmyard manure (+N 40 P 30 K 30 ) enhanced cyanobacterial abundance, and cyanobacterial genera such as Nostoc, Anabaena, Calothrix, Oscillatoria and Phormidium were the dominant forms observed under the wheat crop. The synergistic effect of organic amendments, biofertilizers and chemical fertilizers, especially BGA inoculants, advocates their utilization in wheat crops to improve soil fertility.

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The phenolic profile and specific activity of oxidative enzymes in sorghum leaves and stem resistant and susceptible to Chilo partellus (Swinhoe) were analyzed at 45 and 60 days after germination. Resistant varieties had higher content of total phenols, o-dihydric phenols, flavanols and tannins than the susceptible varieties at both the stages of plant growth and the concentration of these biomolecules increased after infestation as well as with plant age in both sets of varieties. Moreover, resistant varieties exhibited higher specific activity of polyphenol oxidase, peroxidase, phenylalanine ammonia-lyase and tyrosine ammonia-lyase in their leaves and stem in comparison to the corresponding activities in susceptible ones. Peroxidase activity was several folds than the polyphenol oxidase. Healthy leaves of susceptible varieties showed higher catalase activity in comparison with resistant ones at day 45 and this trend was reversed at day 60. Role of phenolic compounds and oxidative enzymes particularly the peroxidase in determining resistance against stem borer has been high lighted.

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Assessment of the qualitative losses in different varieties of sorghum following Pyrilla perpusilla Walker infestation revealed the significant decrease in vitro dry matter digestibility of whole plant, leaves and stem by about 6.0, 3.5 and 3.0 per cent, respectively at more than 60 per cent infestation level and was mainly due to the corresponding increase in tannin content. The fibre components (NDF and ADF) were acting as an additional factor in reducing the dry matter digestibility. The dry fodder yield was also reduced by 46 to 53 per cent in different varieties of sorghum with an increase in infestation level from 0 to >60 per cent. The stem of all the varieties was more fibreous than the leaves as it had high content of NDF, ADF, cellulose and lignin. Leaves on the other hand had high amount of protein, total soluble sugars and reducing sugars than stem and were therefore more digestible than stem.

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A new lichenicolous fungus Melaspilea nitidochapsae colonising on the thallus of Nitidochapsa leprieurii (Mont.) Parnmen, Lücking et Lumbsch is described from India. The new species differs from other known species colonising lichen family Graphidaceae by having completely carbonised exciple, hyaline to pale brown transversely 1-septate ascospores and a different host.

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Nuclear systematics

Part IV. Neutron-capture cross sections and solar abundance

Journal of Radioanalytical and Nuclear Chemistry
Authors:
O. Manuel
,
M. Pleess
,
Y. Singh
, and
W. A. Myers

Summary  

The abundance pattern of s-process nuclides confirms severe mass separation in the Sun and in the parent star that gave birth to the Solar System. The most abundant elements in the interior of the Sun are Fe, Ni, O, Si and S. These five, even-Z elements with high nuclear stability comprize the bulk material of ordinary meteorites and rocky planets close to the Sun. The Sun and other stars operate as giant, magnetic mass-separators that selectively move lightweight elements, and the lighter mass isotopes of each element, to the surface.

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Abstract  

The phase transitions in the LaCrO3 were studied using bulk dilatometry and high temperature X-ray diffractometry from room temperature to 1050 and 1200°C, respectively. LaCrO3 was prepared at 500°C from oxalate precursor employing microwave heating technique. Bulk shrinkage measurements on LaCrO3 pellets were carried out using dilatometer designed and fabricated in our own laboratory. Dilatometric curves of LaCrO3 showed two peaks in ΔL/L vs. temperature curves in the range 200–400 and 800–1000°C, respectively. These phase transitions have been confirmed using high temperature X-ray diffractometry. The role of simple technique like bulk dilatometry in detecting and monitoring the polymorphic transformations in solids is discussed for lanthanum chromates.

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