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Characterizing Spatial Variability of Soil Textural Fractions and Fractal Parameters Derived from Particle Size Distributions

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Pedosphere 2019年第2期29卷 224-234页

作者： Meysam MOHAMMADI Mahmoud SHABANPOUR Mohammad Hossein MOHAMMADI Nasser DAVATGAR Department of Soil Science Faculty of Agriculture University of Guilan Department of Soil Science Faculty of Agricultural Engineering and Technology University of Tehran Department of Soil Science Research Institute of Soil and Water

Soil particle size distribution(PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives of this work were: 1) to partition PSD of 75 soil samples, collected from a flat field in the University of Guilan, Iran, into two scaling domains using a piecewise fractal model to evaluate the relationships between fractal dimensions of scaling domains and soil clay, silt, and sand fractions and 2) to assess the potential of fractal parameters as an index used in a geostatistical approach reflecting the spatial variability of soil texture. Features of PSD of soil samples were studied using fractal geometry, and geostatistical techniques were used to characterize the spatial variability of fractal and soil textural parameters. There were two scaling domains for the PSD of soil samples. The fractal dimensions of these two scaling domains(D_1 and D_2) were then used to characterize different ranges of soil particle sizes and their relationships to the soil textural parameters. There was a positive correlation between D_1 and clay content(R^2= 0.924), a negative correlation between D_1 and silt content(R^2= 0.801), and a negative correlation between D_2 and sand content(R^2= 0.913). The geometric mean diameter of soil particles had a negative correlation with D_1(R^2= 0.569) and D_2(R^2= 0.682). Semivariograms of fractal dimensions and soil textural parameters were calculated and the maps of spatial variation of D_1 and D_2 and soil PSD parameters were provided using ordinary kriging. The results showed that there were also spatial correlations between D_1 and D_2 and particle size *** to the semivariogram models and validation parameters, the fractal parameters had powerful spatial structure and could better describe the spatial variability of soil texture.

关键词： fractal dimension geometric mean diameter geostatistical approach physical property semivariogram model statistical correlation

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Production of autotetraploid plants by in vitro chromosome engineering in Allium hirtifolium

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Horticultural Plant Journal 2023年第5期9卷 986-998页

作者： Nasrin Farhadi Jaber Panahandeh Alireza Motallebi-Azar Sam Mokhtarzadeh Department of Horticultural Science Faculty of AgricultureUniversity of TabrizTabriz 51666-14766Iran Field Crops Department Faculty of AgricultureUniversity of DuzceDuzce 81620Turkey

Persian shallot has been propagated vegetatively through daughter bulbs and has a narrow genetic *** the present study,to create genetic diversity in terms of ploidy level,the effects of in vitro polyploidization were investigated on morphological,physiological and phytochemical *** colchicine treatments(0,0.3%,0.5% and 0.7% concentrations)for 24,36 and 48 h and oryzalin treatments(0,0.001%,0.002% and 0.004% concentrations)for 4,6 and 8 h were used.A sterile basal plate of bulbs was used for the induction of polyploidy in liquid and solid *** obtaining plantlets,root tip chromosomes were counted for the determination of ploidy *** cytometry was performed to confirm the chromosome counting *** regenerated diploid and tetraploid plantlets were transferred to ex vitro *** and oryzalin were both successful in inducing polyploids and the polyploids induced were tetraploids and *** highest induction of polyploidy was obtained in solid media using 0.5%(w/v)colchicine for 36 h(35.0% polyploidy induction)and in 0.001%(w/v)Oryzalin for 8 h(45.5% polyploidy induction).Differences in plantlet height and weight,bulblet weight,density,stomatal width and length,and chlorophyll content were observed between tetraploid and diploid *** duplication,as a result of tetraploid induction,significantly influenced the antioxidant content and enzyme *** results showed that total phenolic content,allicin,and antioxidant capacity were significantly higher in the tetraploid plantlets than that in the diploid *** loci polymorphisms indicated that the 12 autotetraploid plants(with high allicin content)had different genotypes from the parental diploid ***,in vitro polyploidy induction not only duplicated chromosomes but also altered the DNA sequence in Allium *** vitro induction of tetraploids in *** can be a reliable way to obtain suitable plant material for bre

关键词： Persian shallot Allium hirtifolium Polyploidy Colchicine Oryzalin Molecular marker

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A Comparative Study on the Role of Cytokinins in Caryopsis Development in the Maize miniature1 Seed Mutant and Its Wild Type

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Journal of Integrative Plant Biology 2009年第9期51卷 840-849页

作者： Tomaz Rijavec Maja Kova Ale Kladnik Prem S.Chourey Marina Dermastia National Institute of Biology Department of Biotechnology and Systems Biology Department of Biology Biotechnical FacultyUniversity of Ljubljana US Department of agriculture Agricultural Research ServiceChemistry Research Unit

We report here on a comparative developmental profile of plant hormone cytokinins in relation to cell size, cell number and endoreduplicaUon in developing maize caryopsis of a cell wall invertase-deficient miniature1 （mn1） seed mutant and its wild type, Mn1, genotype. Both genotypes showed extremely high levels of total cytokinins during the very early stages of development, followed by a marked and genotype specific reduction. While the decrease of cytokinins in Mn1 was associated with their deactivation by 9-glucosylation, the absolute and the relative part of active cytokinin forms was higher in the mutant. During the exponential growth phase of endosperm between 6 d after pollination and 9 d after pollination, the mean cell doubling time, the absolute growth rate and the level of endoreduplication were similar in the two genotypes. However, the entire duration of growth was longer in Mnl compared with mnl, resulting in a significantly higher cell number in the Mnl endosperm. These data correlate with the previously reported peak levels of the Mn1-encoded cell wall invertase-2 （INCW2） at 12 d after pollination in the Mn1 endosperm. A model showing possible crosstalk among cytokinins, cell cycle and cell wall invertase as causal to increased cell number and sink strength of the Mn1 developing endosperm is discussed.

关键词： 9-glucosylation cell wall invertase cytokinins maize caryopsis miniature1.

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Evaluation of different formulations of IGRs against Aedes albopictus and Culex quinquefasciatus(Diptera:Culicidae)

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Asian Pacific Journal of Tropical Biomedicine 2016年第6期6卷 485-491页

作者： Gul Zamin Khan Inamullah Khan Imtiaz Ali Khan Alamzeb Muhammad Salman Kalim Ullah Entomology Division Nuclear Institute for Food and Agriculture (NIFA) Department of Entomology Faculty of Crop Protection Sciencesthe University of Agriculture Pakistan Central Cotton Committee Cotton Research Station

Objective: To test the relative efficacy of pyriproxyfen and methoprene on mortality,deformity, inhibition and emergence to adult stages of Culex quinquefasciatus and Aedes ***: Serial dilutions(0.01–0.05 mg/L) of methoprene, pyriproxyfen 0.5 water dispersible granules(WDG) and pyriproxyfen 1.0 WDG were used to assess mortality and inhibition of 3rd instar larvae of Aedes albopictus and Culex quinquefasciatus. Each concentration and control was replicated four times in completely randomized *** on larval mortality, growth inhibition, deformities and adult's emergence was recorded weekly. On the basis of best comparative performance, the efficacy of pyriproxyfen 1.0 WDG at 0.1 g/m3 was also tested in the field by collecting treated water samples monthly for 1–6 months after field application. Twenty five 3rd instar larvae of Aedes and Culex spp. of the same cohorts were used for bioassays and compared with larvae in control cups containing 1 L of untreated tap ***: Results revealed variations in fatality of different insect growth regulators(IGRs) to the 3rd instar larvae of Culex and Aedes mosquitoes. Among the IGRs, pyriproxyfen 1.0 WDG was found best that exhibited significantly high emergence inhibition against Culex and Aedes spp. Based on the results, the IGRs were classified in terms of the tested parameters in order of pyriproxyfen 1.0 WDG > pyriproxyfen 0.5WDG > methoprene. In case of field studies, pyriproxyfen 1.0 WDG, pool data of the entire target treated sites showed minimum adult emergence from water sampled of habitats treated with 0.1 g/m3 of pyriproxyfen 1.0 ***: It is thus concluded that IGRs can be utilized as environment friendly control measures for Culex and Aedes spp. of mosquitoes on small and large scale. This will reduce the use of conventional insecticides by the public health authorities and help in reducing selection pressure of insecticides.

关键词： Insect growth regulators Mortality Inhibition Deformities Insecticides Environment friendly

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Effect of water regimes and organic matters on transport of arsenic in summer rice (Oryza sativa L.)

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Journal of Environmental Sciences 2011年第4期23卷 633-639页

作者： Sefaur Rahaman Ashim Chandra Sinha Dibyendu Mukhopadhyay Senior research Fellow Department of Agronomy Faculty of Agriculture Uttar Banga Krishi Viswavidyalaya Pundibari Cooch Behar West Bengal-736165 India. Department of Agronomy Faculty of Agriculture Uttar Banga Krishi Viswavidyalaya Pundibari Cooch Behar West Bengal-736165 India Reader and Head Department of Soil Science & Agricultural Chemistry Faculty of Agriculture Uttar Banga Krishi Viswavidyalaya Pundibari Cooch Behar West Bengal-736165 India

The arsenic contamination in soil-water-plant systems is a major concern of where, the groundwater is being contaminated with arsenic （above 0.01 mg/L） in the Indian subcontinent. The study was conducted with organic matter to find out the reducing effect on arsenic load to rice （cv. Khitish）. It was observed that intermittent ponding reduced arsenic uptake （23.33% in root, 13.84% in shoot and 19.84% in leaf） at panicle initiation stage, instead of continuous ponding. A decreasing trend of arsenic accumulation （root straw husk whole grain milled grain） was observed in different plant parts at harvest. Combined applications of lathyrus ＋ vermicompost ＋ poultry manure reduced arsenic transport in plant parts （root, straw, husk, whole grains and milled grain） which was significantly at par （p 0.05） with chopped rice straw （5 tons/ha ）＋ lathyrus green manuring （5 tons/ha） in comparison to control and corresponding soils. A significant negative correlation of arsenic with phosphorus （grain P with arsenic in different parts R 2 = 0.627–0.726 at p 0.01） was observed. Similarly, soil arsenic had a negative correlation with soil available phosphorus （R 2 = 0.822 at p 0.001） followed by soil nitrogen （R 2 = 0.762 at p 0.01） and soil potassium （R 2 = 0.626 at p 0.01）. Hence, effective management of contaminated irrigation water along with organic matter could reduce the arsenic build up to plants and soil.

关键词： arsenic intermittent ponding lathyrus organic nutrients poultry manure saturation and vermicompost

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Evolution of the “Neutral” : Diverse Forms of Wide-Compatibility Haplotypes at the Locus for Reproductive Isolation

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Molecular Plant 2020年第4期13卷 539-540页

作者： Yohei Koide research faculty of agriculture Hokkaido UniversityKita 9 Nishi 9SapporoHokkaido 060-8589Japan

One of the biggest questions in evolutionary biology is how biological species *** biological species are groups of interbreeding natural populations reproductively isolated from other such groups(Mayer,1942),reproductive isolation is the key process of the *** various isolating barriers,postzygotic barriers ranging from maladaptation to inviability or sterility in the offspring have attracted biologists’attention because of the problem of the evolution of the“unfit”offspring.A clear model to solve this problem is the Dobzhansky-Muller(DM)model(Figure 1;Coyne and Orr,2004),in which incompatibilities are generally caused by an interaction between the genes that have functionally diverged in each population without selection opposing any intermediate step(Coyne and Orr,2004).

关键词： Figure Forms breeding

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Physiological responses of needles of Pinus massoniana elite families to phosphorus stress in acid soil

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Journal of Forestry research 2013年第2期24卷 325-332页

作者： HE You-lan LIU Ai-qin Mulualem Tigabu WU Pengfei MA Xiang-qing WANG Chen Per Christer Oden Forestry College Fujian Agriculture and Forestry University Swedish University of Agricultural Sciences Faculty of Forest Science Southern Swedish forest Research Centre

Pinus massoniana Lamb. is a major timber species widely planted in the South China, where the soil is acidic and deficient in phosphorus （P） due to fixation by aluminum and iron. Understanding the physiological responses to rhizospheric insoluble P is essential for enhancing plantation productivity. Thus, a sand culture experiment was conducted with four levels of P treatment （0, 5, 20 g insoluble P and 10 g soluble P）, and 11 P. massoniana elite families. Physiological responses were measured after two months of stress. Compared to the normal soluble P treatment, the insoluble P treatment significantly reduced the proline content and the APase activity in the needles, while it significantly increased the catalase activity by 1.3-fold and malondialdehyde content by 1.2-fold. Soluble protein content was unaffected by the treatments, but chlorophyll content was significantly lower in P-deprived treatment compared with soluble and insoluble P treatments. These physiological responses also exhibited highly significant variation among families （p 〈 0.01）. The findings suggest that increased catalase activities in the presence of insoluble P might be involved in the activation of an anti-oxidation defense mechanism that scavenges the reactive oxygen species elicited by the stress. And this response has a strong genetic control that can be exploited to identify desirable genotypes.

关键词： Masson pine phosphorus stress anti-oxidative system lipid peroxidation

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Lipophilic extractives of the inner and outer barks from six different Pinus species grown in Indonesia

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Journal of Forestry research 2018年第5期29卷 1329-1336页

作者： Masendra Tatsuya Ashitani Koetsu Takahashi Ganis Lukmandaru Department of Forest Product Technology Faculty of ForestryUniversitas Gadjah Mada faculty of agriculture Yamagata University

The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species（***,***,***,***,***,and ***） grown in Indonesia were investigated by GC and GC–***,the amounts of extractive contents were higher in the inner bark than in the outer bark except for *** acids,monoterpenes,sesquiterpenes,resin acids,triterpenoids,and steroids were detected and *** and outer barks differed not only in content of these compounds but also in their *** acids and alcohols were the major classes of lipophilic compounds in the outer bark of ***, ***,and *** and triterpenoids were the dominant compounds identified in the inner bark of ***,***,and *** acids were the most abundant group in the inner bark of *** whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species.

关键词： Bark extractive Lipophilic Inner bark Outer bark Pinus spp

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Genetic Variability and Phenotypic Correlations Study among Grain Quality Traits and Mineral Elements Concentrations in Colored and Non-Colored Rice (Oryza sativa L.)

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1733-1748页

作者： Adel A.Rezk Mohamed M.El-Malky Heba I.Mohamed Hossam S.El-Beltagi Agricultural Biotechnology Department College of Agricultural and Food ScienceKing Faisal UniversityAl-Ahsa31982Saudi Arabia Plant Pathology research Institute Agriculture Research CenterGiza12619Egypt Rice research and Training Center Field Crop Research InstituteAgriculture Research Center33717Egypt Biological and Geological Sciences Department Faculty of EducationAin Shams UniversityCairo11511Egypt Biochemistry Department Faculty of AgricultureCairo UniversityGiza12613Egypt

Twenty-four rice genotypes were examined to assess genetic variability,heritability,and correlations for seven-grain quality traits,eight nutritional elements,and *** revealed signiﬁcant differences for the quality traits *** every trait under study,the phenotypic coefﬁcient of variation was higher than the correspon-dence genotypic coefﬁcient of *** in a broad sense varied from 29.75%for grain length to 98.31%for the elongation *** percentage recovery had a highly signiﬁcant positive correlation with milling and head rice ***,milling percentage had a highly positive correlation with head rice *** amylose percentage,all the genotypes belonged to low amylose except the Hassawi-1 variety,which had intermediate amylose *** nutrition contents of magnesium(Mg),sodium(Na),potas-sium(K),calcium(Ca),copper(Cu),manganese(Mn),zinc(Zn),iron(Fe),or protein percentage gave different variations for 24 rice genotypes under all the nutritional *** the 24 genotypes,ten rice genotypes–HighNutrient-1,HighNutrient-2,HighNutrient-9,HighNutrient-8,HighNutrient-3,Hassawi-2,HighNutrient-7,HighNutrient-6,Hassawi-1,and HighNutrient-4–had the highest heist value for all nutritional and protein con-tents,and could be used as a donor to improving new *** was a positive and signiﬁcant correlation between magnesium Mg,K,Zn and ***,K had a positive correlation with zinc Zn,Fe,and protein *** analysis was divided into two groups:theﬁrst group included all genotypes rich in nutri-ents,while the remaining genotypes with low nutritional content were included in the second group.

关键词： Amylose cluster analysis genotypes grain quality mineral nutrition rice

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Occurrence and ecotoxicological risk assessment of pesticides in sediments of the Rosetta branch,Nile River, Egypt

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Journal of Environmental Sciences 2022年第8期34卷 21-31页

作者： Fawzy Eissa Mahmoud Al-Sisi Khaled Ghanem Environment and Bio-agriculture Department Faculty of AgricultureAl-Azhar UniversityNasr CityCairo 11884Egypt Central Laboratory of Residue Analysis of Pesticides and Heavy Metals in Food(QCAP) Agricultural Research CenterDokkiGiza 12311Egypt

This study aimed to(1) monitor the occurrence and spatiotemporal variations of 100 pesticides in sediments collected monthly from July 2018 to June 2019 from sampling sites in El-Rahawy, Sabal, and Tala, along the Rosetta branch of the Nile River, Egypt, and(2) perform an ecological risk assessment for aquatic organisms upon exposure to the detected sediment pesticides based on the risk quotient(RQ) method. Out of the 100 pesticides monitored, 16 pesticides belonging to seven chemical families were detected, and 55% of the sediment samples were contaminated with one or more pesticide residues. The mean concentration(mg/kg dry weight(dw)) and detection frequency(%) of the four most frequently detected pesticides in the sediment samples were as follows: chlorpyrifos(0.18 mg/kg dw and 34%), p,p-DDE(0.018 mg/kg dw and 30%), cypermethrin(0.03 mg/kg dw and 14%), and deltamethrin(0.026 mg/kg dw and 13%). The spatial distribution exhibited that El-Rahawy had the highest pesticide load(2.86 mg/kg dw) among the studied sites, whereas the temporal variations revealed that the highest total pesticide concentrations were detected in winter season(1.73 mg/kg dw). Meanwhile, 12 pesticides showed high RQs(>1), posing a potential ecological risk to aquatic species that live and feed on such sediments.

关键词： Pesticide residues Sediments Spatiotemporal variations Risk quotient

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