1,720,961 research outputs found
Effects of nitrogen fertilization management practice on the yield and straw nutritional quality of commercial rice varieties
No full textAn experiment with treatments comprising of five nitrogen rates (0, 120, 160, 200 and 240 kg N/ha) was carried out to assess the effects of nitrogen fertilization management practice on the grain yield and straw nutritive quality in two commercial rice varietiesMR 211 and MR 219. Increases in nitrogen application was found to increase (P<0.01) the grain yield, total spikelets per square meter, number of spikelets per panicle and straw crude protein from 4.56% to a maximum level of 8.45%. It also decreased (P<0.05) the in vitro true dry matter organic digestibility (IVTOMD) from 59.1% to 55.14%, neutral detergent fiber (NDF) and acid detergent fiber (ADF). There were varietal differences in the straw nutritional properties, where MR 219 had higher NDF, hemicellulose and cellulose (P<0.05) concentration where as MR 211 had higher amount of acid detergent lignin (ADL) (P<0.01) and silica (P<0.05) in the straw. Between the two varieties, MR 219 is superior to MR 211 in view of the higher grain production and grain: straw ratio. The result from correlation between agronomic characteristics and straw nutritive quality implies that rice varieties with good agronomic characteristics have potential in yielding straws with better nutritive quality
Effects of Nitrogen Fertilization Levels on the Straw Nutritive Quality of Mr 211 and Mr 219 Rice Varieties
Full text linkRice straw has been used as ruminant feed in many Asean countries although it is
regarded as poor quality feed due to its low protein concentration and digestibility. It has
been reported that the nutritive quality of rice straw varies among different varieties and
is affected by environmental condition that determines its growth pattern. In view of the
reports on the environmental effect on straw quality, this study was designed to evaluate
the nutritive quality of rice straw with increasing application of nitrogen fertilizer.
Samples of rice straw from two varieties, MR 21 1 and MR 21 9 which were grown under
five levels of nitrogen fertilizer (0, 120, 160, 200 and 240 kg Nha) were harvested and
analyzed for chemical composition and digestibility. The results showed that the straw
nutritive quality was improved with nitrogen application.
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Increases in the level of nitrogen fertilization were found to increase the straw crude
protein significantly. The maximum nitrogen level at 240 kg N/ha was found to produce
crude protein of 8.45%, which is above the level required for ruminant feed. The straw
cell wall (NDF) and fiber (ADF) &tion were found to decrease significantly with
nitrogen application. The organic matter digestibility was slightly lowered with
increasing nitrogen level. The concentration of hemicellulose, cellulose, lignin (ADL),
silica, organic matter, ash and the dry matter digestibility were not affected by the
nitrogen fertilization level. In the agronomic characteristics and yield components, the
level of nitrogen was shown to increase the tiller numbers, stem height, maturity, number
of spikelets per panicle, total spikelets per square meter, grain and straw yield and total
yield.
There were significant varietal differences in the concentration of cell wall (NDF),
hemicellulose, cellulose, lignin (ADL) and silica in rice straw, where MR 21 9 had higher
cell wall (NDF), hemicellulose and cellulose concentration where as MR 21 1 had higher
amount of lignin (ADL) and silica in the straw. In the agronomic characteristics, MR 219
had higher number of tillers per plant, total panicles per square meter, total spikelets per
square meter, grain yield, total yield and grain: straw ratio where as MR 21 1 had shorter
stem height, maturity period and higher leaf: stem ratio. Both varieties were shown to
produce straw with improved nutritive quality. In comparison between the two varieties,
MR 219 is superior to MI2 21 1 in view of its higher grain yield and grain: straw ratio.
The grain and straw yield were positively correlated with the straw crude protein and
digestibility and negatively correlated with the cell wall (NDF) and fiber (ADF) fraction
The development and growth of annual clovers for use in dryland pasture
No full textA series of field and controlled environment experiments aimed to quantify development and growth characteristics of arrowleaf, balansa, gland and Persian clovers for introduction to New Zealand dryland pastures. Thermal time requirements for germination were higher for arrowleaf (34 °Cd) than balansa (32 °Cd), gland (28 °Cd) and Persian (25 °Cd) clovers. Persian clover had an optimum germination temperature (Topt) of 33 °C and a maximum temperature (Tmax) of 45 °C, while all the other species had Topt between 16-20 °C and Tmax of ~34 °C. In field and controlled environment experiments, arrowleaf and gland clovers emerged after 90 and 96 °Cd respectively. Balansa and Persian clovers took ~89 °Cd to emerge when sown at soil temperatures below 12 °C. Above 12 °C, they emerged quicker at 75 °C d for balansa and 55 °C d for Persian clover.
Arrowleaf clover produced its first (spade) leaf after 196 °Cd compared with balansa (169 °Cd), gland (175 °Cd) and Persian (154 °Cd) clover. Throughout all sowing dates, phyllochron was the fastest for gland (33-91 °Cd/leaf) and slowest for arrowleaf (53-116 °Cd/leaf) compared with balansa (44-82 °Cd/leaf) and Persian (61-93 °Cd/leaf) clovers. Crops sown into a decreasing photoperiod had a longer phyllochron than those sown into an increasing photoperiod. The influence of photoperiod in modification of the phyllochron affected time to axillary leaf production. A slower phyllochron resulted in longer time to the first axillary leaf.
Autumn sown crops that emerged into a decreasing photoperiod had a longer thermal time requirement to flower than spring sown crops and produced more vegetative growth. Therefore, autumn sowing is recommended to maximise dry matter production. The time to flower became shorter with increasing photoperiod until the longest day of the year before it began to slow down as photoperiod decreased towards autumn. All species are long day plants, which only flower when photoperiod increases above 11.3 hours for arrowleaf, 12.6 hours for balansa, 10.3 hours for gland and 15.4 hours for Persian clover. Gland clover flowered earlier (500–1216 °Cd) compared with balansa (600-1733 °Cd), arrowleaf (940-1834 °Cd) and Persian (1047-2610 °Cd) clovers. The differences in flowering time suggests the suitability of gland clover to be grown in areas that dry out quickly in late spring, balansa clover in areas of wet winter and dry summer, and arrowleaf and Persian clovers in areas that receive high spring rainfall.
In the establishment year, these annual clovers produced dry matter up to 17.5 t/ha for balansa, 12.5 t/ha for Persian, 11.0 t/ha for gland and 9.4 t/ha for arrowleaf clover. Balansa clover had the highest radiation use efficiency of 2.1 g DM/MJ PAR absorbed followed by gland clover (1.6 g DM/MJ PAR) then arrowleaf and Persian clovers (1.3 g DM/MJ PAR). In the second year, regenerated dry matter production at full flower was up to 11.6 t/ha in balansa, 8.3 t/ha in Persian, 2.9 t/ha in gland and 0.5 t/ha in arrowleaf.
Maximum seed production of balansa and gland clovers was 2309 and 2370 kg/ha, respectively in contrast to arrowleaf and Persian clovers which only yielded 914 and 814 kg/ha seeds. In the second year, the percentage seedling emergence from the seed population was 23% for balansa, 19% for Persian, 14% for gland and 10% for arrowleaf clover. These seedlings grew to produce a ground cover up to 91% for balansa, 17% for Persian, 65% for gland and 6% for arrowleaf clover by the end of the second year. Persian clover did not persist because it did not produce any hard seeds. For arrowleaf, balansa and gland clovers, the recovery of hard seeds in the soil after 18 months showed that there was adequate seed production that could sustain on-going regeneration in subsequent years
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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