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51.
Tassaddaq Hussain Hassan S. Bakouch Zafar Iqbal 《Journal of Agricultural, Biological & Environmental Statistics》2018,23(1):63-82
Upon the motivation of unstable climatic conditions of the world like excess of rains, drought and huge floods, we introduce a versatile hydrologic probability model with two scale parameters. The proposed model contains Lindley and exponentiated exponential (Lindley in J R Stat Soc Ser B 20:102–107, 1958; Gupta and Kundu in Biom J 43(1):117–130, 2001) distributions as special cases. Various properties of the distribution are obtained, such as shapes of the density and hazard functions, moments, mean deviation, information-generating function, conditional moments, Shannon entropy, L-moments, order statistics, information matrix and characterization via hazard function. Parameters are estimated via maximum likelihood estimation method. A simulation scheme is provided for generating the random data from the proposed distribution. Four data sets are used for comparing the proposed model with a set of well-known hydrologic models, such as generalized Pareto, log normal (3), log Pearson type III, Kappa(3), Gumbel, generalized logistic and generalized Lindley distributions, using some goodness-of-fit tests. These comparisons render the proposed model suitable and representative for hydrologic data sets with least loss of information attitude and a realistic return period, which render it as an appropriate alternate of the existing hydrologic models. Supplementary materials for this paper are available online. 相似文献
52.
53.
Wheat is one of the most widely cultivated crops and, being the staple diet of more than 40 countries, it plays an imperative role in food security. Wheat has remarkable genetic potential to synchronize its flowering time with favourable environmental conditions. This ability to time its flowering is a key factor for its global adaptability and enables wheat plant to produce satisfactory grain yield under very diverse temperature and soil moisture conditions. Vernalization (Vrn), photoperiod (Ppd) and earliness per se (Eps) are the three genetic systems controlling flowering time in wheat. The objective of this review is to provide comprehensive information on the physiological, molecular and biological aspects of the three genetic constituents of flowering and maturity time in wheat. Reviews written in the past have covered either one of the aspects; and generally focused on one of the three genetic constituents of the flowering time. The current review provides (a) a detailed overview of all three gene systems (vernalization, photoperiod and earliness per se) controlling flowering time, (b) details of the primer sequences, their annealing temperatures and expected amplicon sizes for all known markers of detecting vernalization and photoperiod alleles, and (c) an up to date list of QTLs affecting flowering and/or maturity time in wheat. 相似文献
54.
55.
Mohammad Ashik Iqbal Khan Kihachi Ueno Sakae Horimoto Fuminori Komai Kinji Tanaka Yoshitaka Ono 《Biology and Fertility of Soils》2009,45(3):305-313
The aims of this study were to monitor the changes in physicochemical, including spectroscopic, and biological characteristics
during composting of green tea waste–rice bran compost (GRC) and to define parameters suitable for evaluating the stability
of GRC. Compost pile temperature reflected the initiation and stabilization of the composting process. The pH, electrical
conductivity, NO3
−-N content, and carbon-to-nitrogen ratio were measured as chemical properties of the compost. The color (CIELAB variables),
humification index (the absorption ratio Q
4/6 = A
472 / A
664 of 0.5 M NaOH extracts), absorption at 665 nm of acetone extracts, and Fourier-transform infrared (FT-IR) spectra were measured
to evaluate the organic matter transformation; germination of komatsuna or tomato seeds was measured to assess the potential
phytotoxicity of composting materials during composting. No single parameter was capable of giving substantial information
on the composting process, the nutrient balance, phytotoxicity, and organic matter decomposition. The FT-IR spectra at 3,300,
2,930, 2,852, and 1,065 cm−1 provided information on the molecular transformation of GRC during composting and they decreased over the composting. Most
of the assayed parameters showed no further change after about 90 days of composting suggesting that GRC can be used for agricultural
purposes after this period. 相似文献
56.
57.
Shahid Iqbal Awan Muhammad Shahzad Ahmed Jehanzeb Farooq Syed Dilnawaz Ahmad Muhammad Ilyas Asad Hussain Shah Muhammad Fareed Khan Sardar Ali Lutful Hasan 《Frontiers of Agriculture in China》2011,5(4):486-496
An experiment was conducted to access the genetic variability among early vigour and quantitative traits under limited moisture
in F2 generation of a 5 × 5 diallel cross of bread wheat. The results indicated that there was significant genotypic variation
among the genotypes. Additive dominance model revealed full fitness of the data for RL, DSW, FRW, DRW, spike length, and 1000-grain
weight but was partially fit for SL, FSW, R/S, tillers per seedling, plant height, tillers per plant, spikelets per spike,
and grain yield per plant. The partially adequate models for these plant characters might be due to the presence of non-allelic
interaction, linkage, and non-independent distribution of the genes in the parents. Additive genes coupled with moderate to
high narrow sense heritability were involved in the heritage of all the traits, which indicated a higher scope of selection
in early generations. 相似文献
58.
Muhammad Sajid Muhammad Ali Khan Wasim Bilal Abdur Rab Zafar Iqbal Sana Irshad khan 《Gesunde Pflanzen》2017,69(3):113-121
Peach fruit is enriched with natural antioxidants but oxidation caused by biotic and abiotic stresses, reduce these antioxidants and consequently effect the quality and yield of the fruit. Therefore, an experiment was conducted to investigate the role of ascorbic acid to sustain the natural antioxidant activity, improve the fruit quality and yield of peach cultivars (Early Grand and Florida King). The peach cultivars, Early Grand and Florida King were tested against four levels of ascorbic acid (200, 400, 600 and 800?ppm) and compared with control as water spray. The foliar application of ascorbic acid significantly influenced anti-oxidant activity and physico-chemical attributes of peach cultivars. However, the foliar application of ascorbic acid @ 800?ppm significantly increased the fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity, antioxidant activity of fruit peel, with least percent infected fruits and fruit juice pH as compared to the rest of the treatments. Similarly, significant variation was recorded for peach cultivars regarding anti-oxidant activity and various physico-chemical attributes. The maximum fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity and TSS/TA ratio were noted in fruit of cultivar Florida King. On other side the foliar treated fruit of peach cultivar Early Grand had the highest percent infected fruits, fruit juice pH and antioxidant activity of fruit peel. It is concluded from the significant findings of present research that the peach cultivar Florida King performed better in terms of maximum fruit yield, whereas the cultivar Early Grand produced better quality fruits with high anti-oxidant activity when treated with 800?ppm of ascorbic acid as foliar spray. 相似文献
59.
Michelle Salazar-López Magdalena de J. Rostro-Alanis Carlos Castillo-Zacarías Ana L. Parra-Guardado Carlos Hernández-Luna Hafiz M. N. Iqbal Roberto Parra-Saldivar 《Water, air, and soil pollution》2017,228(12):469
In this study, in-house isolated laccase isoforms, i.e., Lac-I and Lac-II of the basidiomycete Pycnoporus sanguineus (CS43), were evaluated in relation to their Remazol Brilliant Blue R (RBBR) dye degradation capacity. A modified Dhouib medium additionally supplemented with 3% ethanol as a secondary inducer was used to propagate P. sanguineus CS43 for enhanced production of laccase under liquid state fermentation. The crude laccase extract was purified by passing through ion exchange diethylaminoethanol (DEAE)-Sepharose and gel filtration-based Sephadex G-200 column chromatography. The purified laccase fractions were subjected to the electrophoresis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed two laccase isoforms Lac-I and Lac-II with 66 and 68 kDa, respectively. To explore the industrial applicability, for RBBR dye, degradation efficiencies ranged from 82 to 88% after 3 h of incubation for both; Lac-I and Lac-II at both concentrations were recorded. However, with 8 U/mL, the degradation ranged between 70 to 80% during the first 5 min of incubation. Enhanced degradation of RBBR dye was obtained in the presence of violuric acid and N-hydroxypthalamide as laccase mediators. Finally, using RBBR as a substrate kinetic characterization of both Lac-I and Lac-II isoforms was performed that revealed K m (0.243 and 0.117 mM for Lac-I and Lac-II) and V max (1.233 and 1.012 mM/Sec for Lac-I and Lac-II) values, respectively. 相似文献
60.
Sumaira Qutab Rizwan Rasheed M. Arslan Ashraf Iqbal Hussain Nudrat Aisha Akram 《Archives of Agronomy and Soil Science》2017,63(13):1900-1911
The effects of selenium (Se) cadmium (Cd) interactions on plant growth and metabolism are not fully clear. In the present study, we assessed whether Se could alleviate the toxic effects of Cd on growth and metabolism of maize. Seeds of maize variety FH-985 were sown in pots filled with sand treated with CdCl2 (0, 50 and 100 µM) and Se (0, 2 and 4 mg L?1) through Hoagland’s nutrient solution. Low Se (2 mg L?1) increased germination percentage and rate, while high Se (4 mg L?1) increased fresh and dry biomass under Cd stress. Interestingly, all Se concentrations were effective in alleviating the toxic effects of Cd on photosynthetic pigments, whereas higher Se mitigated the Cd-induced oxidative stress and increased flavonoids both in the shoots and roots while phenolics in the roots. The results demonstrated that root zone Se altered tissue-specific primary metabolism in maize. Furthermore, low Se mitigated the Cd-induced decrease in total proteins in the root. Overall, Se-mediated decrease in the oxidative stress in the shoots while increase of secondary metabolites in the roots helped the plants to grow faster at early growth stage and caused increase in the biomass under different Cd regimes. 相似文献