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1.
In this study, interactions of nickel sulfate and urea sprays on vegetative growth, yield and leaf mineral contents in strawberry were investigated. Rooted Pajaro strawberry plants were potted in 3 liter pots filled with soil, leaf mold and sand (1:1:1, v/v/v). Established plants were foliar sprayed with nickel sulfate at 0, 150, 300 and 450 mg L?1 and urea 0 and 2 g L?1 concentrations. Results indicated that nickel (Ni; 300 mg L?1) plus urea (2 g L?1) significantly increased the yield and runner numbers. Nickel sulfate at the rate of 300 and 150 mg L?1and urea (2 g L?1) significantly increased the crown numbers. The greatest root fresh and dry weights were obtained from untreated plants. Urea at 2 g L?1 without nickel significantly increased shoot fresh and dry weights. Nickel at 450 mg L?1 without urea significantly increased Ni concentration in leaves. Overall, nickel sulfate at 150 and 300 mg L?1 along with urea at 2 g L?1 were the best treatments. 相似文献
2.
Abolfazl Zare Mohammad Morshed Rouhollah Bagheri Keikhosro Karimi 《Fibers and Polymers》2013,14(11):1783-1793
Radical melt graft copolymerizations of poly (lactic acid) (PLA) with amide monomers using benzoyl peroxide as an initiator during reactive extrusion is studied. The effects of two monomer types at various concentrations, reaction temperatures and initiator concentrations on the grafting yield are investigated. The results showed that percentage of grafting was significantly enhanced by increasing benzoyl peroxide concentrations up to 12 mpm and then decreased by an increase in the initiator concentration. Furthermore, increasing each monomer concentration up to 450 mpm, improved the grafting yield significantly. Further increase brings about a marked fall in the grafting yield. Fourier Transform Infrared Spectroscopy (FTIR), back titration and nitrogen analyses confirmed that monomers of acrylamide and methacrylamide were successfully grafted onto PLA. The Gel Permeation Chromatography (GPC) data showed that the molecular weight of the grafted PLA samples under optimum conditions does not show any dramatic drop of PLA molecular weight by thermal degradation or hydrolysis of polyester chains, while the polydispersity index is poorly affected by the chemical modification of PLA. Also, the monomer structures affected the grafting yield as well as polymer chain combination. In addition under the same conditions, the grafting yield of acrylamide was more than that of methacrylamide. Thermal properties, molecular weight, density, moisture regain and tensile properties of the samples were also measured. 相似文献
3.
Zahra Ranjbar Mehran Torki Amir Ali Karimi Torshizi 《Journal of animal physiology and animal nutrition》2019,103(5):1418-1426
In ovo injection (IOI) of Naringin (N), flavanone was examined on post‐hatch blood biochemical parameters, antioxidant status and bone characteristics. Fertile eggs (n = 700) were distributed in seven groups with 100 eggs. On 14th and 17.5th days of incubation, four groups were injected using 15 or 30 mg active ingredient levels of naringin/0.5 ml saline/egg, low and high level, into amnion sac. Controls include sham (injected normal saline, 0.5 ml/egg on day 14 and 17.5th) and un‐injected group. IOI of high naringin and saline on 14th day of incubation resulted in lower hatchability and then higher mortality in last week of embryonic life. On day hatch, high levels of injected groups more body weight compared to the control. Chick length was increased at high levels of naringin on day 17.5th compared to control and saline injected. Quality traits of bones were improved in naringin‐injected groups compared to control. IOI of naringin influenced thyroid hormones on 14th day of incubation. Naringin groups influenced the Alkaline phosphatase (ALP), Calcium (Ca), superoxide dismutase (SOD), blood biochemical and lipids. Totally, amniotic IOI of naringin in last days of developing embryo may be useful for hatched chick, development of leg long bone or effect on biochemical metabolites by levels of flavanone that it needs more research. 相似文献
4.
Rouhollah Karimi Abdolhossein Rezaei Nejad Shahrokh Khanizadeh 《The Journal of Horticultural Science and Biotechnology》2016,91(4):386-395
The effects of exogenous application of abscisic acid (ABA) on anti-oxidant enzyme activities and photosynthetic capacity in ‘Sultana’ grapevine (Vitis vinifera L.) were investigated under cold stress. When vines had an average of 15 leaves, 0 (control), 50, 100, or 200 µM ABA was sprayed to run-off on all leaves of each plant. Twenty-four hours after foliar spraying with ABA, half (n = 5) of the water-only control vines and half (n = 5) of each group of ABA-treated plants were subjected to 4°C for 12 h, followed by a recovery period of 3 d under greenhouse conditions (25°/18°C day/night). The remaining plants in each treatment group were kept at 24°C. Cold stress increased H2O2 and malondialdehyde (MDA) concentrations in vine leaves, whereas all foliar ABA treatments significantly reduced their levels. Chilled plants showed marked increases in their total soluble protein contents in response to each ABA treatment. ABA significantly increased the activities of superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase in cold-stressed grapevine leaves. In contrast, cold stress markedly decreased the rates of leaf photosynthesis (A) and evaporation (E), stomatal conductance (gs), and chlorophyll concentrations in leaves, but increased intercellular CO2 concentrations (Ci) in leaves. Treatment with all concentrations of ABA resulted in lower leaf A, E, and gs values, but higher Ci values at 24°C. However, following cold stress, ABA-treated vines showed higher leaf A, E, and gs values, but lower Ci values compared to control vines without ABA treatment. The application of 50–200 µM ABA allowed chilled vines to recover more quickly when re-exposed to normal temperatures, enabling the vines to resume their photosynthetic capacity more efficiently following cold stress. These results showed that, by stimulating anti-oxidant enzyme systems and alleviating cold-induced stomatal limitations, ABA reduced the inhibitory effect of cold stress on the rate of CO2 fixation in ‘Sultana’ grapevine plants. 相似文献
5.
Fatemeh Ranjbar Parviz Rezvani Moghaddam Alireza Koocheki 《Communications in Soil Science and Plant Analysis》2017,48(7):801-807
Essential oil content and concentration of anise plant planted in different times under various sources of nitrogen was evaluated in this study. The experiment was conducted in a split plot based on a randomized complete block (RCB) design (different sources of fertilizer as the main plot and planting dates as subplots) with three replications in the Agricultural Research Station at Ferdowsi University of Mashhad in 2015–2016. Treatments included: planting times (sub plot factor): (27th of October, 27th of November, 1st of March, 10th of March, and 8th of April) and nutritional sources (main plot factor): (Cow Manure, Chemical Fertilizer, and mixture of Cow Manure + Chemical Fertilizer). The results showed that the anise plant essential oil qualitative characteristics were significantly influenced by treatments. Also, interaction between the fertilizer treatments and planting dates on the essential oil content and concentration of the plants were significant. The highest percentage of plant essential oil (3.71%) was found in the cow manure treatment, and the lowest percentage of essential oil (2.95%) was obtained in the chemical fertilizer. The highest essential oil yield (16.09 kg/ha) was found in the mixed treatment of the cow manure and the chemical fertilizer, and the chemical fertilizer treatment had the lowest rate of essential oil yield (11.41 kg/ha). The highest percentages of the plant oil (14.31%) and the plant oil yield (77.46 kg/ha) were found in the integrated treatment of the cow manure and the chemical fertilizers. The lowest amounts of the plant oil (12.19%) and the plant oil yield (41.28 kg/ha) were found in the chemical fertilizer. According to the percentage and the yield of the essential oil, the best planting time and fertilizer treatment was the one on 10th of March and using integrated cow manure and chemical fertilizer. 相似文献
6.
Shirazi MH Ranjbar R Eshraghi S Amin G Nouri MS Bazzaz N 《Pakistan journal of biological sciences: PJBS》2008,11(3):487-489
Antibacterial activity of Sage extract at concentrations of 0.1, 0.05, 0.025, 0.0125, 0.00625, 0.003125, 0.00156, 0.0005 and 0.00025 g dL(-1) against Salmonella typhi, Shigella sonnei, S. flexneri, Proteus vulgaris, Staphylococcus aureus, ETEC Escherichia coli and Pseudomonas aeruginosa was evaluated. Susceptibility testing of bacterial strains against 18 antibiotics was also performed for comparison. The results showed that P. aeruginosa and ETEC E. coli were completely resistant to Sage extract even at concentration of 0.1 g dL(-1). Its antibacterial activity (0.1 g dL(-1)) against P. vulgaris, S. flexneri and S. sonnei was the same as nitrofurantoin and ampicilline respectively. Sage extract (0.1 and 0.05 g dL(-1)) exhibited the same effects as ampicilline and streptomycin against S. typhi. Its antibacterial activity (0.1, 0.05 and 0.25 g dL(-1)) against S. aureus was the same as ceftazidim, chloramphenicol, gentamycin, neomycin and nitrofurantoin and was more significant compared to streptomycin and vancomycin. The results suggest Sage can be considered as an alternative herbal in the treatment of infections caused by the above-mentioned bacteria. 相似文献
7.
Quimby PC DeLoach CJ Wineriter SA Goolsby JA Sobhian R Boyette CD Abbas HK 《Pest management science》2003,59(6-7):671-680
Research by the USDA-Agricultural Research Service (ARS) on biological control of weeds has been practiced for many years because of its inherent ecological and economic advantages. Today, it is further driven by ARS adherence to Presidential Executive Order 13112 (3 February 1999) on invasive species and to USDA-ARS policy toward developing technology in support of sustainable agriculture with reduced dependence on non-renewable petrochemical resources. This paper reports examples or case studies selected to demonstrate the traditional or classical approach for biological control programs using Old World arthropods against Tamarix spp, Melaleuca quinquenervia (Cav) ST Blake and Galium spurium L/G aparine L, and the augmentative approach with a native plant pathogen against Pueraria lobata Ohwi = P montana. The examples illustrated various conflicts of interest with endangered species and ecological complexities of arthropods with associated microbes such as nematodes. 相似文献
8.
Linguatula serrata is a cosmopolitan zoonotic parasite with its adult form occurring in the nasal and respiratory passages of canids as the
definitive hosts, while its immature stages localize in the mesenteric lymph nodes, liver, spleen, lungs, and, rarely, in
other organs, such as the ocular region of herbivorous intermediate hosts. Humans can behave as both intermediate and final
host and are infected by visceral and nasopharyngeal linguatulosis. Consumption of infected, improperly cooked viscera of
the intermediate hosts, including sheep, goats, cattle, camels, or other herbivores containing the larval stages of this parasite
is a potential source of infection of human beings with the nasopharyngeal form of linguatulosis. However, nasopharyngeal
secretions or feces of carnivores containing eggs of Linguatula are the main sources for infecting human beings with the visceral form of this infection. In the present study, the prevalence
of infection by nymphs of L. serrata in 101 camels in Yazd Province, central Iran, was estimated based on histopathological studies of samples from two, apparently
enlarged, mesenteric lymph nodes (MLN), together with one sample from a whitish pinpoint spot on the liver and spleen of each
animal. Thirteen camels (12.9%) were infected with the nymphal stage of L. serrata. Age and sex did not play a significant role in the prevalence of this parasitic infection. The number of parasites in each
MLN ranged from one to six larvae. In view of the consumption of raw or undercooked liver and visceral organs of camel by
humans of this region, the importance of careful inspection at slaughter needs to be emphasized. 相似文献
9.
The effects of NaCl salt (EC = 16 dS m−1) on water potential, and accumulation of proline, Na+ and K+ in leaves on the main stem of 30 wheat cultivars (Triticum aestivum L.) at awn appearance and 20 days after anthesis (20 DAA) were evaluated in a greenhouse experiment. Plants were arranged
in a according to a randomized complete block design with factorial treatments in three replications. Proline accumulation
at 20 DAA increased with increasing salt stress. This increase was 27.4-fold with the salt-sensitive cultivar “Ghods,” while
the mean was 5.2-fold for 19 salt-resistant cultivars. Positive correlations between proline, and K+ + Na+ concentrations associated with higher sensitivity to salt stress indicated that proline may not have a protecting role against
salt stress. No correlation was observed between leaf proline and water potential. Almost no contribution to the osmotic adjustment
seems to be made by proline. The contribution made by proline to the osmotic adjustment of plants at 20 DAA was 0.69 bar,
whereas that made by K+ and Na+ was 2.11 and 4.48 bar, respectively. The 30 wheat CVs used in this experiment showed different performances regarding the traits observed. Eleven of them showing the higher stress
sensitivity indices had the highest level of proline and Na+ concentrations. They were considered to be salt-sensitive cultivars. Among the others, nine cultivars showed salt tolerance
with almost the same Na+ and proline concentrations, but a higher K+/Na+ selectivity of ions from leaf to grains. In 10 of the cultivars, Na+ and proline concentrations were low, indicating the presence of a salt avoiding mechanism. 相似文献
10.
This study was conducted to investigate the effect of time on chemical forms of P in 10 calcareous soils of western Iran. Phosphorus was added to soils at the rate of 200 mg kg?1 as KH2PO4. The samples were incubated for 1, 7, 15, 30, 60, 90 and 120 days at 25°C and constant moisture. After incubation, P was fractionated by the sequential extraction procedure: soluble and exchangeable P (NaHCO3-P) Al + Fe-P (NaOH-P), Ca-P (HCl-P) and residual P (Res-P). The distribution of added P into different fractions consisted of two phases involving initial rapid retention followed by a slow continuous retention. In general, the majority of the P applied entered mostly in the HCl-P and Res-P fractions. After 120 days incubation, the HCl-P fraction remained the most dominant in all soils. A combination of silt and sand content of the soils together explained between 88.5 and 83.3% of the variance inNaHCO3-P and HCl-P transformation rates, respectively, 76.6 and 72.8% of which is explained by silt alone. CaCl2-P and electrical conductivity (EC) together accounted for 66.3% of the variation in the rate constant of NaOH-P. The release rate of Res-P was not significantly related to soil properties. 相似文献