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1.
The object of this study was to investigate the frictional properties (repose angles and friction coefficient) of Iranian sunflower seed and its kernel (Fandoghi, Azargol and Shahroodi) as a function of moisture content, size and variety. The static coefficient of friction were determined on five structural surfaces including aluminium, plywood, galvanized iron, polyethylene and rubber when moisture content varied between 3 and 14 % d.b. The obtained results showed that static coefficient of friction on five studied surfaces increase linearly as moisture content increase from 3 to 14% for both seed and kernel. Among the applied surfaces, rubber showed the highest value of friction coefficient for both sunflower seed and kernel followed by plywood, polyethylene, galvanized iron and aluminium. The obtained values of emptying and filling angles of repose increase linearly with an increase in moisture content. Furthermore, the values of empting and filling angles of repose for small sizes were higher than big sizes in all levels of moisture content for both seed and kernel. Also, the emptying angle of repose assumed higher values than the filling angle of repose for all varieties and categories.  相似文献   

2.
The present study evaluated the effect of feed particle size, thermal processing, several levels of fat inclusion and moisture addition on pellet quality and protein solubility in potassium hydroxide (KOH) in a corn, soybean meal and animal by products based broiler diets. The different processing factors were combined in a 2 x 4 x 4 x 2 factorial arrangement in an eight randomized block consisting of eight production series: two particle sizes (coarse: 1,041 microns and medium: 743 microns), four fat inclusion levels at the mixer (15, 25, 35 and 45 g/kg of feed), four moisture addition levels in the conditioner (0, 7, 14 and 21 g/kg of feed) and two thermal processing treatments (conditioner-pellet press treatment or conditioner-expander-pellet treatment) which resulted in 64 different processed feeds. For the determination of the pellet durability index (PDI), the amount of intact pellets and protein solubility determinations, eight feed samples (replicates) were collected for each treatment. The data were transformed using a variation of Box-Cox transformation in order to fit a normal distribution (p 〉 0.05). Adding moisture up to 21 g/kg of feed in the conditioner improved pellet quality of the diets (p 〈 0.05). Expansion of diets before pelleting improved (P 〈 0.05) PDI and amount of intact pellets by 26% and 31%, respectively, as compared to a simple conditioning-pelleting feed processing. Expander treatment (at 110 ℃) decreased (p 〈 0.05) protein solubility in KOH from 686 g/kg to 643 g/kg total protein as compared to pelleting process (at 80-82 ℃). The amount of intact pellets reduced from 773 g/kg to 746 g/kg of feed (/7 〈 0.05) as particle size increased from medium to coarse grinding. Pellet quality was significantly reduced with fat inclusion levels higher than 35 g/kg of diet.  相似文献   

3.
Some engineering properties of sunflower seed and its kernel, Shahroodi variety as a case study, were investigated at various moisture content levels (3-14% d.b.) for three size categories (large, medium and small). With increase of moisture content from 3 to 14% d.b., all the main dimensions (length, width and thickness), geometric mean diameter, porosity, true density, terminal velocity and static coefficient of friction increased while bulk density and rupture force for both sunflower seed and its kernel decreased for all size categories. The results showed that the highest value of static coefficient of friction for both seed and kernel was on the rubber surface, followed by plywood, polyethylene, galvanized iron, and finally aluminium surfaces. The seeds required less compressive force to dehull when loaded under the horizontal as compared to the vertical orientation. But for kernels, the trend was the opposite. Also, the compressive forces needed to initiate rupture of sunflower seed hulls were higher (47.1-94.72 N) than those required to rupture the kernel (8.5-13.4 N) in both orientations.  相似文献   

4.
This study attempts to examine the effects of salinity on leaf, stem, and nut of Pistacia vera (Ohady and Kaleh Ghochi cultivars) in order to characterize their anatomical structures with electron and light microscopy. A comparative study of the anatomy indicates a difference between the density of simple and glandular trichomes in leaf surface, deposit of wax, the thickness of leaf, the length of epidermal cells, palisade parenchyma cells, crystals in mesophyll, and the manner of compatibility to salinity. The results obtained in this research demonstrate that compatibility of Ohady cultivar is higher than Kaleh Ghochi and the degree of mechanical wounding depends on their development stages. In addition to results of previous studies which considered crop load as the main cause of fruit deformity. The present study indicates that, in spite of some reduction in total production of a tree, salinity decreases fruit deformity and to a high extent prevents the production of deformed fruit. Indeed, a remarkable reduction in production of deformed fruit will be yielded by selecting pistachio varieties which are resistant to salinity. Moreover, salinity increases the resistance of nuts to mechanical wounding. The results of this study suggest that in EC = 7.6, 12.6 deformity of nut is not related to crop load.  相似文献   

5.
The study area is located in Duhok and Sulaimania province in Kurdistan region, lraq. Study soils developed from parent material that has derived from limestone. Randomize, composed and disturbed surface soil samples were collected. The bulk soils were air dried, crushed and passed through 2 mm sieve. Standard methods were used for chemical, physical, geotechnical and mineralogical analyses of soil samples. The results indicated that the study soils texture were clay to loam clay, this texture was considered as suitable for ceramic and pottery industries as a result of increasing clay contents that ranged between 301 g/kg and 676 g/kg. Soil consistence depending on geotechnical properties increased the ability of study soils for resistance rapture and deformation. Existence the high amount of cementing agents in study soils such as organic matter, iron oxides and particularly total carbonate (247.2-308.8 g/kg) act to reduce the bad effect of the smectite minerals group (high shrinkage) in soils of study locations through increasing the resistance of these soils for rupture and deformation. The existing of Kaolinite, palygorskite and chlorite allows clay to be dried in ceramic and pottery industries without cracking from shrinkage. Study soils were different in their colors as a result of existence, different pigmentation materials that led to coloring soils with different colors in turn caused coloring of pottery and ceramic materials. Since, there are no available academic studies or researches about this subject in Kurdistan region in addition the clay pottery and ceramic sector still has a good market at the same time using this type of soils for arts, therefore, this study was conducted.  相似文献   

6.
The effects of different tillage systems and poultry manure on soil physical properties, performance and nutrients in sorghum were studied for three years at Owo, southwest Nigeria. There was factorial combinations of herbicide-based zero tillage (ZT), manual clearing (MC), disc ploughing (P), ploughing plus harrowing (P+H) and ploughing plus double harrowing (P+2H), and two rates of poultry manure at 0 and 7.5 Mg ha^-1. Herbicide-based zero tillage and manual clearing reduced soil temperature and conserved more water than mechanized tillage techniques. Poultry manure reduced soil bulk density and temperature and increased soil water and porosity. There was a percentage decrease of leaf N, P, K, Ca and Mg concentrations, plant height, leaf area, stem girth, root dry weight, dry matter and grain yield in ascending order for herbicide-based zero tillage, manual clearing, ploughing, ploughing plus harrowing and ploughing plus double harrowing while percentage increases were recorded in a descending order for all the various combinations of tillage with poultry manure in that order. Poultry manure in combination with tillage increased dry matter and grain yield by 33.1 and 39.5%, respectively in comparison with tillage only. The manure-zero tillage methods increased dry matter and grain yield by 8% and 15%, respectively when compared with manure-mechanized tillage methods. Zero tillage or manual clearing in combination with 7.5 Mg ha^-1 poultry manure was most suitable for sorghum cultivation.  相似文献   

7.
Knowledge about crop growth processes in relation to N limitation is necessary to optimize N management in farming system. Plant-based diagnostic method, for instance nitrogen nutrition index (NNI) were used to determine the crop nitrogen status. This study determines the relationship of NNI with agronomic nitrogen use efficiency (AEN), tuber yield, radiation use efficiency (RUE) and leaf parameters including leaf area index (LAI), areal leaf N content (NJ and leaf N concentration (N0. Potatoes were grown in field at three N levels: no N (N 1), 150 kg N ha^-1 (N2), 300 kg N ha^-1 (N3). N deficiency was quantified by NNI and RUE was generally calculated by estimating of the light absorbance on leaf area. NNI was used to evaluate the N effect on tuber yield, RUE, LAI, NAL, and NL. The results showed that NNI was negatively correlated with AEN, N deficiencies (NNI〈 1) which occurred for N 1 and N2 significantly reduced LAI, NL and tuber yield; whereas the N deficiencies had a relative small effect on NAL and RUE. To remove any effect other than N on these parameters, the actual ratio to maximum values were calculated for each developmental linear relationships were obtained between NNI and tuber RUE to NNI. stage of potatoes. When the NNI ranged from 0.4 to 1, positive yield, LAI, NL, while a nonlinear regression fitted the response of  相似文献   

8.
In Kenya almost all sugarcane grown is under rainfall conditions that are planted in different locations during both long and short rainy seasons. Effect of season, location, cultivar and spacing on yield and quality of sugarcane is not clearly understood. The research was conducted at Kibos and Mumias to determine if the yields and quality of three sugarcane cultivars were affected by season, location and row spacing. Cultivars CO 945, EAK 73-335 and KEN 83-737 were manually planted during June and September in 2011. The trial was laid out as split-split plot arranged in a randomized complete block design (RCBD) replicated three times. Data collected at harvest, 17 months after planting (MAP) including cane yields, cane yield components and cane quality. The results revealed that cane length differed significantly between June and September. Stalk population and cane yields were significantly more at Mumias compared to Kibos. Cultivar EAK 73-335 showed significantly more cane yield (t/ha) than KEN 83-737 and CO 945. Both row spacing 1.2 m and 1.5 m did not affect cane yields. Brix%, Sucrose% and Purity% differed significantly between cultivars. The relationship between cane yield and stalk population was positive and significant, which indicated stalk population is a strong determinant of cane yield. The results showed that cane yield was significantly affected by location and cane quality by cultivars. Therefore Mumias is a better zone for sugarcane cultivation for both June and September seasons compared to Kibos.  相似文献   

9.
Farmers may not be conscious for their farmland's nutrients, soil organic matter, water and air because they simply concerned only for their labor availability and soil fertility losses. The composition and proportion of these components greatly influence soil physical properties, including texture, structure and porosity, the fraction of pore space in a soil. The soil of this farmland must be able to supply adequate amount of plant nutrients, in forms which can be absorbed by the crop, within its lifespan. Deficiencies or imbalances in the supply of any of essential elements can compromise growth, affecting root development, cell division, crop quality, crop yield and resistance to disease and drought. This study was conducted to fill this knowledge gap in order to develop economically vital and environmentally accepted nutrient management strategies for the use of soils in agricultural lands. The objective of this study is to assess the elemental contents and concentration of soil samples collected from farmlands of "Yebrage" using neutron activation analysis (NAA) techniques regardless of oxidation state, chemical form or physical locations. NAA is used to determine the elemental composition and concentrations present in a soil. The macro/micronutrient and organic matter deficiencies have been verified in agricultural soils through increased use of soil testing and plant analysis. The challenge for agriculture over the coming decades will meet the world's increasing demands for food in a sustainable way. Current issues and future challenges point out that as long as agriculture remains a soil based industry, major decreases in productivity likely to be attained ensuring that plants do not have adequate and balanced supply of nutrients.  相似文献   

10.
Essential oils (EOs) from Rosemary, Rosmarinus officinalis (Lamiaceae), Orange, Citrus sinensis (Rutaceae), Lavandula, Lavandula angustifolia (Lamiaceae), False Yellowhead, Dittrichia viscosa (Asteraceae) and their major components were evaluated against root knot nematode, Meloidogyne incognita and Meloidogynejavanica. Second stage juveniles' (J2) paralysis and egg hatch inhibition were studied, while pulverized plant parts were tested for nematodes biological cycle arrest. All EOs paralyzed J2 and M. incognita were found more sensitive than M javanica with the EC50/4 days calculated at 250, 3,650 and 4,260 12g/mL for 1). viscosa, L. angustifolia and R. officinalis, respectively. Similarly, all EOs inhibited nematodes egg hatch and D. viscosa exhibited the highest inhibition on egg hatch (100% inhibition at 5 μg/mL). A significant influence of constituent terpenes (limonene, 1,8-cineole, linalool, camphor, L-borneol, caryophyllene oxide, β-eudesmol) dose and exposure time was indicated on egg hatch inhibition (56% to 100% at 500 μg/mL and 1,000 μg/mL), while only β-eudesmol achieved paralysis of J2 and specifically against M. incognita (EC50/1d = 50μg/mL). Interestingly, the most active botanical species arresting Meloidogyne spp. biological cycle in soil was C. sinensis (EC50 = 2 mg/g) and the most sensitive nematode species was M. javanica. The larvicidal and egg hatch inhibition activity holds promise towards the optimization of artificial terpene mixtures as novel and effective natural nematicides. Complex interactions of primary compounds and subsequent decomposition derivates compose efficacy profile of soil amendments.  相似文献   

11.
The present study aims to understand the effects of long-term fertilization on soil organic carbon (SOC), black carbon (BC), enzyme activity, and the relationships among these parameters. Paddy field was continuously fertilized over 30 yr with nine different fertilizer treatments including N, P, K, NP, NK, NPK, 2NPK (two-fold NPK), NPK+manure (NPKM), and CK (no fertilization), N, 90 kg urea-N ha^-1 yr^-1; P, 45 kg triple superphosphate-P205 ha^-1 yr^-1; K, 75 kg potassium chloride-K20 ha^-1 yr^-1; and pig manure, 22 500 kg ha^-1 yr^-1. Soil samples were collected and determined for SOC, BC content, and enzyme activity. The results showed that the SOC in the NPKM treatment was significantly higher than those in the K, P, and CK treatments. The lowest SOC content was found in the CK treatment. SOC content was similar in the N, NP, NK, NPK, 2NPK, and NPKM treatments. There was no significant difference in BC content among different treatments. The BC-to-SOC ratios (BC/SOC) ranged from 0.50 to 0.63, suggesting that BC might originate from the same source. Regarding enzyme activity, NPK treatment had higher urease activity than NPKM treatment. The urease activity of NPKM treatment was significantly higher than that of 2NPK, NP, N, P, K, CK, and NPKM treatment which produced higher activities of acid phosphatase, catalase, and invertase than all other treatments. Our results indicated that long-term fertilization did not significantly affect BC content. Concurrent application of manure and mineral fertilizers increased SOC content and significantly enhanced soil enzyme activities. Correlation analysis showed that catalase activity was significantly associated with invertase activity, but SOC, BC, and enzyme activity levels were not significantly correlated with one another. No significant correlations were observed between BC and soil enzymes. It is unknown whether soil enzymes play a role in the decomposition of BC.  相似文献   

12.
Pelargonium sidoides DC is used in herbal medicine for the treatment of various infections. The roots are being indiscriminately harvested for local and export trade and the collection rate is becoming unsustainable. Seed germination dynamics of this species was studied with the aim to reveal factors that influence its survival in the wild in order to adopt the appropriate germination conditions for use in ex-situ propagation and conservation program. Germination was affected by age of seeds, temperature and pre-chilling conditions. Temperature higher than 25 oC reduced germination by 60%. When seeds of P. sidoides were subjected to pre-chilling treatment for seven days, there was a significant drop in final germination by 29% compared to the other treatments. Although, final germination was not affected by different light treatments, continuous light significantly promoted germination velocity Seeds harvested from the plants grown in the green house performed better in germination than those collected from the field. The ecological implications of these observations on the propagation and conservation ofP. sidoides are discussed.  相似文献   

13.
Plant extracts could turn out to be herbicides used in weed control. We evaluated the herbicidal effect of seven plants from the Al-Qassim Region of Saudi Arabia on germination and growth of Phalaris minor, Echinochloa crusgalli, Portulaca oleracea and Lactuca sativa. In the laboratory, plant extracts at 5, 10, 20 and 40 g/L inhibited the germination and seedling growth of test seeds. P. minor and P. oleracea were more sensitive to the extracts than L. sativa and E. crusgalli. The germination of either P. minor or P. oleracea were completely inhibited by Prosopisjuliflora at 10 g/L and by Rumex vesicarius and Teucrium baccatus at 20 g/L. Extract of Pulicaria undulate completely inhibited germination of target seeds at concentrations ranged from l 0 g/L to 40 g/L. The rank order of bioactivity was Prosopis jul(17ora 〉 Pulicaria undulata 〉 Rumex vesicarius 〉 Withania somnifera 〉 Teucrium baccatus 〉 Artemisia monosperma 〉 Anvillea garcinii. In the greenhouse trial, the extracts of seven plant species at 30, 60 and 90 g/L reduced growth of six-weeks-old target plants. Anvillea garcinii and Prosopisjuliflora showed the greatest effects. At 90 g/L, the reduction in the growth of target species reached between 20% and 30% for Anvillea garcinii and between I 1% and 25% for Prosopis juliflora. Overall, Prosopis juliflora, Pulicaria undulata, Anvillea garcinii and Rumex vesicarius had potential for use as natural herbicides or for development as novel plant-derived herbicides.  相似文献   

14.
It is predicted that the current atmospheric CO2 concentration will be doubled and global mean temperature will increase by 1.5-6°C by the end of this century. Although a number of studies have addressed the separate effects of CO2 and temperature on plant-insect interactions, few have concerned with their combined impacts. In the current study, a factorial experiment was carried out to examine the effect of a doubling CO2 concentration and a 3℃ temperature increase on a complete generation of the brown planthopper (Nilaparvata lugens) on rice (Oryza sativa). Both elevated CO2 and temperature increased rice stem height and biomass of stem parts. Leaf chlorophyll content increased under elevated CO2, but only in ambient temperature treatment. Water content of stem parts was reduced under elevated temperature, but only when coupled with elevated CO2. Elevated CO2 alone increased biomass of root and elevated temperature alone enhanced leaf area and reduced ratio of root to stem parts. Brown planthopper (BPH) nymphal development was accelerated, and weight of and honeydew excretion by the F1 adults was reduced under elevated temperature only. Longevity of brachypterous females was affected by a signiifcant interaction between CO2 and temperature. At elevated temperature, CO2 had no effect on female longevity, but at ambient temperature, the females lived shorter under elevated CO2. Female fecundity was higher at elevated than at ambient temperature and higher at elevated CO2 than at ambient CO2. These results indicate that the combined effects of elevated temperature and CO2 may enhance the brown planthopper population size.  相似文献   

15.
Isoprenoids are a functionally and structurally diverse class of natural organic chemicals. The universal precursors of all isoprenoids, isopentenyl diphosphate and dimethylallyl diphosphate are synthesized through the mevalonate and 2C-methyl- D-erythritol 4-phosphate (MEP) pathways, respectively. Many isoprenoids produced through the MEP pathway play an important role in plant acclimation to different light environments. Eupatorium adenophorum, an invasive weed in China, presents a remarkable capacity to acclimate to various light environments, which constitutes its solid foundation of being a successful invasive species. Thus we aimed at gaining a deeper insight into the regulation of MEP pathway in E. adenophorum to further understand the invasive mechanism. 2C-Methyl-D-erythritol 2,4-cyclodiphosphate synthase (IspF or MCS) is an essential enzyme in the MEP pathway. In this paper, a novel IspF gene was cloned and characterized from E. adenophorum. Tissue-specific expression assays revealed a higher expression of EalspF1 in leaves than in stems and roots. The expression of EalspF1 was responsive to different light conditions. Some up-regulation of EalspF1 expression was also found after the treatments with signal compounds and after wounding stress. Interestingly, the over-expression of EalspF1 in Arabidopsis led to increase carotenoids contents, resulting in an enhanced tolerance to high light. Taken together, these results indicate that the EalspFl-derived enzyme participates in isoprenoid metabolism and among others, the expression of this gene in E. adenophorum is involved in the regulation of plastidial isoprenoids, which play an important role in acclimation to various light environments.  相似文献   

16.
The effects of two culture systems, conventional and no-till combined the previous crop (lentil and wheat) on soil properties were studied in the experimental site of the station Technical Institute for Field Crops (ITGC) Setif (Algeria) during the crop year 2011/2012. The results indicate that the no-till system affects positively the variables of soil properties and the organic matter has a rate of 2.89% compared to 2.44% in conventional tillage. If the conventional system has an infiltration of moisture relatively higher than that observed for no-till throughout the cycle, the no-tillage is distinguished by a higher storage of moisture at the end of cycle wheat cultivation. The results also indicate that the density (1.44 g/cm), permeability (22.79 cm/h) and soil compaction (12.51 kg/cm) in no-till were significantly higher compared to conventional tillage 1.35 g/cm, 14.13 cm/h, 7.40 kg/cm, respectively.  相似文献   

17.
The present study was aimed to investigate the anti-arthritic activity of alcoholic extract ofClerodendron inerme which was shown to inhibit inflammatory process. Arthritis was induced in rats by injecting rats intradermally with Freund's adjuvant 0.01%-0.1% in paraffin oil. They were grouped and received 10 mg/100 gm b.wt. of alcoholic fraction of C. inerme, 1.5 mg/100 gm b.wt. hydrocortisone and saline, orally, for 15 days. The arthritic scores, radiological scores, body weights, liver glycogen, serum mucoproteins were monitored for 49 days. Wilcoxan ranking methods and Student's t Test were used to determine the significance changes between control and treated groups. Adjuvant-arthritic rats showed a significant decrease in body weight, liver glycogen, increased serum mucoprotein and severity of periostitis and other degenerative changes m the bone. But treatment with the alcoholic fraction (apigenin, scutallarin and pectinolinergenin) of C. inerme exhibited a very good relief from the arthritic conditions by increasing the body weight, increased liver glycogen content and registered little degenerative changes in bones, suggesting long term anti-arthritic activity when compared to the control group. The anti-arthritic activity ofC. inetme alcoholic fraction was remarkable in this study. However, further studies are required to elucidate its full anti-arthritic potential.  相似文献   

18.
19.
Cellular retinoic acid-binding protein 1 (CRABP1) is a well-conserved member of cytosolic lipid-binding protein family. It is an important modulator of retinoic acid signaling. Long serial analysis of gene expression (LongSAGE) analysis suggested that CRABP1 gene was differentially expressed during prenatal skeletal muscle development in porcine. Here, we obtained the full-length coding region sequence and genomic sequence of the porcine CRABP1 gene and analyzed its genomic structures. Subsequently, we examined CRABP1 chromosome assignment using INRA-University of Minnesota 7 000 porcine radiation hybrid panel (IMpRH) and explored its tissue distribution in adult Tongcheng pigs and dynamical expression profiles in prenatal skeletal muscle (33, 65 and 90 days post coitus, dpc) from Landrace (lean-type) (described as L33, L65 and L90) and Tongcheng pigs (obese-type) (described as T33, T65 and T90). The CRABPI gene was mapped to chromosome 7ql 1-q23 and closely linked to the microsatellite marker SWR1928. Quantitative real-time PCR showed that CRABP1 mRNA was highly expressed in lung and stomach, moderately expressed in placenta and uterus, and weakly expressed in other tissues. Moreover, CRABP1 gene was down-regulated during prenatal skeletal muscle development in both Landrace and Tongcheng pigs and it was expressed much higher in T33 than L33. Two single-nucleotide polymorphisms (SNPs) were detected by sequencing and mass spectrometry methods, allele frequency analysis indicated that g. 281 (G〉A) and g. 2992 (G〉A)were deviated from Hardy-Weinberg equilibrium in the Landrace and DLY (Duroc×(Landrace×Yorkshire)) pig breeds.  相似文献   

20.
Simple sequence repeats (SSR) have been widely used as molecular markers due to their abundance and high polymorphism, However, up to now, the SSR markers had not been developed in the obligate biotrophic phytopathogenic fungus, Blumeria graminis f.sp. tritici. From (AC)10 and (AG)10 enriched genomic libraries for Bgt, 25 primer pairs were designed using the FIASCO (fast isolation by AFLP of sequences containing repeats) protocol. Five primer pairs exhibited polymorphism with allelic diversity from two to seven alleles and produced 29 alleles in a survey of 90 isolates collected from six provinces (cities) in China, while the others displayed monomorphic. Levels of observed heterozygosity ranged from 0.000-0.044 (mean 0.025) and expected heterozygosity ranged from 0.297-0.816 (mean 0.538). These molecular markers provide a novel source to genetic diversity assays and to genetic and physical mapping ofBgt. SSR markers of Bgt need to be further explored.  相似文献   

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