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101.
dos Santos Araújo Fernando Arriel Nair Helena Castro de Medeiros Everaldo Paulo de Lima Liziane Maria de Souza Mayara Andrade de Andrade Alberício Pereira de Lucena Alcântara Bruno Riselane 《Genetic Resources and Crop Evolution》2022,69(3):1219-1227
Genetic Resources and Crop Evolution - The remaining populations of perennial cotton (Gossypium hirsutum L. r. marie-galante Hutch.) that occur in northeastern Brazil are part of the primary gene... 相似文献
102.
L. -A. Appelqvist Baboo M. Nair 《Plant foods for human nutrition (Dordrecht, Netherlands)》1977,27(3-4):255-263
The analysis of bulk seed samples of some selected Swedish cultivars showed thatBrassica campestris cultivars contain higher amounts of alanine, valine and aspartic acid than those ofB. napus, whereasB. sinapis cultivars contain higher amounts of glycine and aspartic acid and slightly more threonine and phenylalanine. The amino acid analysis was carried out by gas chromatography.
Zusammenfassung Die Analyse von Samenproben einiger selektierter Sorten zeigte, dasz Sorten vonBrassica campestris höhere Gehalte an Alanin, Valin, Asparaginsäure besitzen als Sorten vonB. napus. Dagegen verfügen Sorten vonB. sinapis über höhere Gehalte an Glycin und Asparaginsäure und etwas mehr an Threonin und Phenylalanin. Die Aminosäurenbestimmungen erfolgten gaschromatographisch.
Résumé Lés analyses d'échantillons massifs de graines de certains cultivars selectionnes en Suéde ont montré que les cultivars deBrassica campestris contiennent des taux plus élevés d'alanine, valine, acide aspartique, que ceux deB. napus, tandisque les cultivars deB. sinapis contiennent des taux plus élevés de glycocolle et d'acide aspartique, et un peu plus de thréonine et de phénylalanine. Les analyses d'aminoacides ont été faites par chromatographie en phase gazeuse.相似文献
103.
A comparative study of phenylpropanoid metabolism in gamma irradiated and unirradiated potato tubers
Summary Phenylpropanoid metabolism in gamma irradiated potato tubers was studied by examining the pattern of incorporation of radioactivity
from U-14C phenylalanine into caffeic acid. chlorogenic acid and the coniferyl and sinapyl moieties of lignin. During a post-irradiation
period of 21 days a depletion in chlorogenic acid was observed. This is a result of its impaired synthesis as well as an accelerated
conversion of chlorogenic acid to ferulic and sinapic acids and their deposition in lignin.
The results offer an explanation for the lower level of chlorogenic acid invariably observed in irradiated potato tubers. 相似文献
104.
K. C. Lakkineni A. Sivasankar P. A. Kumar T. V. R. Nair Y. P. Abrol 《Journal of plant nutrition》2013,36(10):2213-2217
Application of 10 mM urea to the flag leaf of wheat plants enhanced in vivo urease activity several fold. Photosynthetic rate was also increased considerably. There were significant differences in the leaf internal carbon dioxide (CO2) concentrations between the urea‐treated and untreated leaves. The finding that carbon (14C) was detected in the ethanol extract of the leaves fed with 14C‐urea suggests that CO2 released from urea is re‐fixed by the leaves. 相似文献
105.
In view of the difficulties in stand volume estimation in natural forests, we derived real form factors and models for volume estimation in these types of forest ecosystems, using Katarniaghat Wildlife Sanctuary as a case study. Tree growth data were obtained for all trees (dbh >10 cm) in 4 plots (25 × 25 m) randomly located in each of three strata selected in the forest. The form factor calculated for the stand was 0.42 and a range of 0.42 0.57 was estimated for selected species (density >10). The parameters of model variables were consistent with general growth trends of trees and each was statistically significant. There was no significant difference (p>0.05) between the observed and predicted volumes for all models and there was very high correlation between observed and predicted volumes. The output of the performance statistics and the logical signs of the regression coefficients of the models demonstrated that they are useful for volume estimation with minimal error. Plotting the biases with respect to considerable regressor variables showed no meaningful and evident trend of bias values along with the independent variables. This showed that the models did not violate regression assumptions and there were no heteroscedacity or multiculnarity problems. We recommend use of the form factors and models in this ecosystem and in similar ones for stand and tree volume estimation. 相似文献
106.
Pontamine fast scarlet 4B: a new fluorescent dye for visualising cell wall organisation in radiata pine tracheids 总被引:1,自引:0,他引:1
Jimmy Thomas Manfred Ingerfeld Hema Nair Shakti Singh Chauhan David A. Collings 《Wood Science and Technology》2013,47(1):59-75
Using confocal microscopy, tracheid wall organisation was investigated with pontamine fast scarlet 4B (P4B), a cellulose-specific stain that fluoresced red following green excitation. P4B fluorescence was present throughout unlignified walls (cambium, ray cells, resin canals and parenchyma cells) and in two concentric bands around opposite and compression wood tracheids. Scanning electron micrographs demonstrated these bands as the S1 and S3 layers of normal wood, and the S1 and inner S2 layers of compression wood. Fluorescence was also strongly dependent on the polarisation of the excitation light, a phenomenon referred to as bifluorescence. Compared to two other cell wall stains, Congo red and calcofluor white, P4B showed a higher specificity for the S1 and S3 layers and increased bifluorescence. These results suggest that P4B is an ideal tool with which to investigate the orientation of cellulose microfibrils in the S1 and S3 layers of the tracheid wall. 相似文献
107.
Wendy Francesconi P. K. R. Nair Douglas J. Levey Jaret Daniels Laury Cullen Jr. 《Agroforestry Systems》2013,87(6):1321-1338
Agroforestry practices, such as Shaded Coffee and Homegardens, may provide habitat for forest butterflies and contribute to their conservation in fragmented agricultural landscapes. To determine the influence of agroforestry practices in an agricultural mosaic, the distribution of fruit-feeding butterflies was studied using a systematic approach that compared butterfly species richness in six land-use practices (Eucalyptus [Eucalyptus spp.], Shaded Coffee, Homegardens, Secondary Growth, Pastures, and monocultures of Cassava [Manihot esculenta] and Sugarcane [Saccharum officinarum]), and in natural habitat (secondary Forest Edge and Interior) in two study areas (agricultural landscapes). In each study area, Van Someren-Rydon butterfly traps were placed as a grid every 150 m, creating quadrants of 2.2 and 2.4 km2 that encompassed the different land-use practices. Land-use, plot area, number of traps and distance to the forest were set as covariates to compare species richness values. Butterfly species composition was compared using linear discriminant analysis (LDA). With the exception of Pastures, Cassava and Sugarcane, significant differences were not identified between the rest of the agricultural land-use practices and the forest habitats (edge and interior). The species composition in the agricultural practices was however, different to that found in forest habitats. Overall, Shaded Coffee practices that represent long-term mixed tree and crop stands have a better potential of conserving forest butterfly species compared to monoculture practices. 相似文献
108.
SummaryAnnatto (Bixa orellana L.) is a tree indigenous to tropical America that has been naturalised throughout the Indian sub-continent. The plant is chiefly valued for its carotenoid pigments, annatto. Methods for the clonal propagation of hardwood and softwood cuttings, air-layering, budding, and grafting of annatto were investigated. Hardwood cuttings collected during the wet Summer months (June-July) were treated with indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), or naphthaleneacetic acid (NAA) at varying concentrations. The highest percentage rooting (63.4%), along with highest number of roots (8.33 per cutting) were achieved by hardwood cuttings after 12 h of 2.5 mM IAA treatment. Among the various auxin treatments of softwood cuttings, 5.0 mM IBA in combination with 5.0 mM NAA for 5 min resulted in a significant (P < 0.05) rooting percentage (56.7%). The responses of softwood cuttings to an auxin analogue (boric acid) and/or to thiamine hydrochloride (vitamin B) were inferior to synthetic auxins. When subjected to air-layering, hardwood branches gave 100% rooting without any application of hormone. Among the different types of budding methods attempted (patch, T, or I), patch budding produced the highest efficiency (78%) of propagation. Splice-grafting could also be used for conventional propagation of annatto, with a 50% survival rate. Annatto can therefore be cloned by adopting these methods. Propagation based on softwood cuttings facilitated moderate-scale cloning of this valuable, elite germplasm. 相似文献
109.
110.
Freshwater prawn production in India that includes farming and wild capture of the giant freshwater prawn, Macrobrachium rosenbergii and the monsoon river prawn, M. malcolmsonii has increased steadily since 1999 reaching a peak output of 42 780 t in 2005, but then declined to 6568 t in 2009–2010. Stunted growth and diseases in ponds because of poor seed quality and the broodstock which had been inbred over several generations; pond water quality issues; and increased cost of production on account of feed, labour and the mandatory certification requirements are suggested to be some of the factors leading to the production declines. While majority of the output occurs in Andhra Pradesh, single crop paddy–prawn production systems in the low‐lying fields of Kerala have helped gradual transformation to a sustainable, organic mode of farming of both rice and prawns, suitable for other states of India. Although the trends by June 2011 indicate that the sector is set to a revival, future prospects of freshwater prawn farming in India will also depend on the expansion of whiteleg shrimp Litopenaeus vannamei that was introduced recently in India and provided a more profitable opportunity for farming. 相似文献