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1.
Mohammad Kazem Souri Moin Naiji Mohammad Hossein Kianmehr 《Journal of plant nutrition》2019,42(6):604-614
Manure urea pellets were produced and their nitrogen release rate was evaluated in soil incubation at different water contents of 90, 75, and 60% soil filed capacity (FC). In another experiment, sweet basil growth was evaluated during eight months (with three shoot harvests) under the pellet application. The nitrogen release and pellet dispersion rates were slow after two months or at lower soil water content (60% FC), but they were significant after four months of soil incubation, or at higher soil water content (75 or particularly 90% FC). Application of pelleted urea reduced plant growth and yield at first harvest than urea treatment. However, at second and particularly at third harvest (and the average of three harvests) significant improvement in growth parameters of SPAD value, leaf area, plant height, shoot fresh weight, pot yield, and` leaf N and K concentrations were achieved by application of pelleted urea fertilization. 相似文献
2.
Soil weathering is recognizable through study on physico-chemical characteristics of soil. In this study, Parker, ([(Na)a / 0.35] + [(Mg)a / 0.9] + [(K)a / 0.25] + [(Ca)a / 0.7]) × 100, and Product, [SiO2 / (TiO2 + Fe2O3 + SiO2 + Al2O3)] × 100, weathering indexes, originally developed for study on rocks, were tested on Yellow Brown Forest soils from two different regions in Japan. The results showed that the contribution of the mentioned indexes can be used for study on soils weathering. In other word, in a two-dimensional coordination system where the axes are Parker and Product indexes, regarding to the chemical bases of the indexes, initial and lateral products of weathering can be tracked at the same time.
Additionally, the indexes relations with soil color were studied after exposing the samples at a high temperature. Remarkable relationships between a* / b* ratio–parameters of psychometric chromaticness of color in CIE color standard system–and these two weathering indexes demonstrated that a* / b* ratio can be applied reliably to estimate the quantities of Parker and Product indexes in Yellow Brown Forest soils. 相似文献
3.
This study was made on the effects of a normal diet containing 12.8 mg Cu kg(-1) DM which added gradually molybdenum and sulphur on the copper status and fibre quality in eight 1-year Merghoze goat. One group (n = 4 mean weight 31 +/- 2.0 kg) was treated with Mo and S supplements for 20 weeks, the second group (n = 4 mean weight 32 +/- 2.1 kg) served as controls. In addition of blood sampling for measuring copper status in plasma, the copper content and quality of fleeces were measured every 6 weeks. Mohair measurements were carried out by taking patch samples (10 x 10 cm2) from the mid-side area of the goat. The analytical set consists of plasma copper concentrations (Pl Cu), Trichloroacetic acid soluble copper concentrations (TCA-Cu), and fleece copper content. The results indicated that the addition of 20-30 mg Mo and 2-2.5 g S kg(-1) DM to the normal diet did produce sub clinical copper deficiency in treated goats. One such visual symptom was the loss of fleeces pigmentation and poorer crimp being observed. The Pl Cu minus TCA-Cu plasma became more than 2 microM in the blood of treated goat, indicating that there was a significant thiomolybdate formation in the body. The results showed that there was a significant decrease in Pl Cu (p < 0.05) along with a significant increase in thiomolybdate (MoS) production after 4 months. The sub clinical signs of copper deficiency and mohair quality are likely to be from high molybdenum intake and thiomolybdate formation in the body. 相似文献
4.
Talebi J Moghaddam A Souri M Mirmahmoudi R 《Tropical animal health and production》2012,44(2):355-360
The present study aims were to determine the profiles of changes in progesterone (P4) and 17-β-estradiol (E2) in the peripheral
blood of Markhoz goat (Iranian Angora) during estrous cycle, gestation, and parturition throughout natural breeding season.
Gestation length averaged 145.3 ± 0.8 days, and the litter size was 1.1 ± 0.1. Birth weight ranged 2.4–2.8 and 1.5–2.5 kg
in male and female kids, respectively. The mean estrous cycle lengths were 20.3 ± 0.4 and 20.9 ± 0.4 days for PGF2α-induced and natural cycles, respectively. Blood sampling was carried out daily during estrous cycle and weekly during gestation
till parturition. E2 attained higher level (24.7 ± 2.15 pg mL−1) at estrus phase and dropped down to the lower level (18.80 ± 1.16 pg mL−1) within 3 to 4 days post-estrus. Concomitantly, P4 started to increase from the mean basal value of 0.5 ± 0.03 ng mL−1 on day 0 to 6.88 ± 0.95 ng mL−1 on day 6 of estrous cycle and reached the peak value of 12.8 ± 0.61 ng mL−1 on day 12. From day 15, a decline was observed in P4 values till the end of the cycle. P4 remained at lower concentrations
for 20–50 days of gestation, then increased and reached to its maximum level (13.51 ± 0.279 ng mL−1) in week 15 and returned again to its basal values within 1–2 weeks before parturition. The results will be discussed in
terms of the usage of steroid hormone profile in several assisted reproductive technologies. 相似文献
5.
Plants have the ability to suppress microbial nitrification process through secondary metabolites released from their root exudates or/and leaf litter. For decades, grasses were suggested to control nitrification process, and recently, Brachiaria humidicola accession 26159 (BH) as a tropical and subtropical grass has been shown to reduce nitrification rates under laboratory and soil conditions. In this study, experiments were conducted under controlled conditions in nutrient solution culture to investigate whether the reported release of natural nitrification inhibitors from root exudates of BH is an active or passive phenomenon. So different variables such as N-form (nitrate vs. ammonium), collecting medium (distilled water vs. 1 mM NH4Cl) and collecting period (6 vs. 24 hrs) were included to study the hypothesis. Results showed when root exudates were collected in distilled water there was no nitrification inhibition activity for all ammonium and nitrate grown plants. However, when collection was done in a medium containing 1 mM NH4Cl, root exudates showed significant nitrification inhibition activity similar to results obtained by Subbarao et al. The observed nitrification inhibition activity had a positive correlation to ammonium treatment particularly in collection medium, probably due to root cells damage induced by low pH and membrane depolarization under ammonium nutrition. This was more supported by application of shoot homogenates of NH4+, NO3? or NH4NO3 grown plants that showed significant nitrification inhibition activity compared to distilled water and DMPP controls in a bioassay test, independent of N-form. Potassium concentrations in root exudates (as a result of potassium leakage) were found to increase in root washings of plants, which were grown with ammonium, particularly when root exudates were collected in 1 mM NH4Cl solution. In addition, higher electric conductivity of root washings after collection of root exudates in ammonium containing medium (low pH) and also in nitrate containing medium which adjusted to pH 3 by applying H2SO4, strongly suggest that release of natural nitrification inhibitors from root exudates of B. humidicola may not be an active process, but instead it is rather a passive phenomenon by ammonium induced root physicochemical damages. 相似文献
6.
A nutrient solution experiment was carried out to evaluate effects of different magnesium (Mg) concentrations (0, 25, 50, 75 and 100 percent of magnesium concentration of Hoagland solution) on growth and physiological characteristics of Iranian melons (Cucumis melo var. inodorus subvar. Khatouni). The experiment was done based on completely randomized design using plastic pots and sand culture. The results showed that SPAD value of leaves, plant leaf number, stem diameter, shoot fresh and dry weight, root fresh weight, chlorophyll b, carotenoids, protein, catalase and peroxidase activities were constantly increased by increasing Mg levels of nutrient solution until 75 or 100% Mg levels, while leaf area, petiole length, internodes length were highest in lower levels of Mg compared to full Mg of nutrient solution. Moreover, the leaf concentrations of nitrogen (N), phosphorus (P), potassium (K), magnesium, and iron (Fe), but not calcium (Ca), were increased by increasing magnesium concentration to full Hoagland nutrient solution Mg level. 相似文献
7.
Mohammad Kazem Souri 《Journal of plant nutrition》2017,40(7):1035-1044
Nitrification inhibitory properties of plant substances offer potential benefits for agricultural applications. In this study, hexane-extracted seed oil, and 10, 20, and 30 mg/pot dry powder of seed exocarp and mesocarp from Acrocomia totai were applied in a quick nitrification bioassay for 24 or 50 hr, as well as for 4 weeks laboratory soil incubation, to investigate their effects on nitrification process. Results showed that applied oil concentrations significantly reduced nitrification rates. The extent of inhibition was increased with the oil concentrations from 5 to 25 µl in both experiments. The exocarp and mesocarp powders also inhibited nitrification, but it was not as high as oil-induced inhibition. Analysis of oil fatty acids showed that oil consisted of 71%, 26%, and 3% of saturated, monounsaturated, and polyunsaturated fatty acids, respectively. This suggests that fatty acids or some unknown ingredients in crude oil could be the responsible inhibiting compound. 相似文献
8.
Mohammad Kazem Souri Moin Naiji Maryam Aslani 《Communications in Soil Science and Plant Analysis》2018,49(2):215-224
Iron (Fe) has very low solubility and plant availability in calcareous soils, and this generally results in restricted plant production and low quality. During last decades, various commercial chelated fertilizers have been used in agricultural systems to meet iron requirements of crops. However, despite extensive application of these commercial chelate fertilizers, there is real doubt and high concerns regarding many aspects of their action, dynamics, efficiency, and safety in plant-soil–environment systems. In the present study, growth and quality of green bean plants (Phaseolus vulgaris L.) were evaluated under foliar and soil applications of Fe-glycine chelate (iron glycine aminochelate) and commercial Fe-EDDHA chelate in a lime soil. The results showed that morphophysiological parameters were improved by the application of Fe-glycine and Fe-EDDHA treatments. Foliar application of Fe-glycine has significantly improved leaf area and Soil-Plant Analyses Development (SPAD) values compared to control and Fe-EDDHA treatments. Pod yield, shoot (but not root) dry weight, and iron concentrations in leaves and pods (but not in root) were significantly higher when plants were treated by Fe-glycine rather than Fe-EDDHA in both soil and foliar applications. Vitamin C and protein contents were significantly improved and phenolic compounds were reduced by foliar application of Fe-glycine and soil application of Fe-EDDHA. The results indicate that foliar application of Fe-glycine can significantly increase Fe concentrations and quality of beans under lime soils with restricted iron availability. 相似文献
9.
Chelates are compounds that are applied to improve nutrition, especially the micronutrients status of plant tissues. During past decades, various chelating agents have been synthesized and introduced to agricultural systems. The recent formulas are aminochelates that are synthesized using various amino acids and a single or several nutrient ions aimed at improving fertilizer use efficiency and more adaptation to environment protection. Apart from their primary use as a micronutrient source, aminochelates represent an effective nitrogen (N) fertilizer in plant nutrition that can avoid negative effects from simple N fertilizers, such as urea. In various studies, higher yield and quality as well as higher concentration of nutrient elements have been obtained by application of aminochelates rather than simple chemical fertilizers. These compounds claimed to be more natural and safer forms of chelating agents, with higher use efficiency and without environmental side effects. However, there is lack of sufficient knowledge especially regarding their detailed impacts and their fate within the soil and plant system. This review provides information concerning the role of aminochelates in plant nutrition and to summarize the previous recent studies that have been done using these fertilizers. 相似文献
10.