[en] This greenhouse study conducted on a Mediterranean Terra Rose soil in an unheated plastic greenhouse was designed to investigate the response of drip-irrigated tomatoes (Lycopersicon esculentum Mill.) and peppers (Capsicum annum) to four nitrogen levels continually applied with irrigation stream. Water containing 0,67,134 or 201 mgN/l and uniformly supplied with 80 and 240 mg/l of P and K, respectively, were applied two times a week. Three adjacent plants in each plot were fertigated with N¹⁵ labeled NH₄S₂O₄ (2% a.e. enrichment). For each plant the amount of water, P, K and the N¹⁵ applied through the bottles was to that amount applied through a single dripper. In addition to the fertigation soil application of 400 kgN/ha was included with three adjacent plants in each plot were fertilized receiving N¹⁵ labeled (3.3 % a.e. enrichment) The total amount of water applied was 392 mm and the resulting N application totals ranged from 200 to 600 kgN/ha. According to the results obtained, the maximum yield of tomatoes and peppers were achieved with 67 mgN/l (200 kgN/ha) treatment. The percentage fertilizer utilization by tomatoes was highest with 67 mgN/l (200 kgN/ha), which was followed by 134 mgN/l (400 kgN/ha) .The percentage fertilizer utilization was the lowest with 201 mgN/l (600 kgN/ha) or soil application (400 kgN/ha). The results indicated that the percentage fertilizer utilization of tomatoes was significantly greater by the fertigation than the soil application of N at the same level fertilization (400 kgN/ha). The fertilizer N uptake by peppers was significantly greater with 134 mgN/l (400 kgN/ha) than the other applications. The results indicated that although the percentage fertilizer utilization was the same, the fertilizer N uptake by peppers was significantly greater with the fertigation than the soil application of N at the same level fertilization (400 kgN/ha)

[en] In order to determine the Nsub^2-fixation capacities of lentil, vetch, chickpea and fodderpea in a legume-wheat rotation by using the A-value method of N¹⁵ technique, and to assess the amount of carry-over of N to wheat from the previous legume as well as water contribution of fallow, wheat and legumes to the following wheat under rainfed Central Anatolia conditions field experiments were conducted in 1992 and 1993 at three different provinces using completely randomized block design with 5 replications. Results we obtained showed that %Ndff values among legumesdid not differ significantly neither within or between locations. Legumesvaried significantly (P<0.05) in their %Ndfa values at each location and highest values of %Ndfa were obtained at Eskisehir. In general, %Ndfa varied from59-84, and 36-85 for chickpea,lentils and vetchs. The evaluation of the yield and N data obtained in 1993 indicated that lentil (winter or summer) -wheat rotation at Ankara and Eskisehir conditions and chickpea-wheat rotation at Konya conditions should be prefered, due to the higher seed and total yields, higher N yields and higher %NUE values obtained from these rotations in comparison to the others. In order to estimate the carry-over of nitrogen from legumes to the succeeding wheat crop, % nitrogen derived from unknown (%Ndfu) were also calculated. Highest amount of carry-over from the legumesto the succeeding wheat were 31.1 kgN/ha from summer lentil at Ankara; 16.9 kgN/ha from summer lentil at Eskisehir; and 8.0 kgN/ha from chickpea at Konya. These results obtined showed that a lentil-wheat rotation at Ankara and Eskisehir and a chickpea-wheat rotation at Konya. Mean while, the evaluation of the soil and WUE data at both Eskisehir and Ankara indicated that winter lentil-wheat rotation should be prefered in these areas due to more efficient use of water by wheat crop after this rotation system

[en] In this study, activities of radioactive polonium and natural radionuclide concentrations in fertilizer most consumed in agricultural lands in Turkey were measured. Fertilizers containing phosphorus and potassium increase yield and quality. But, they contain some radionuclides. These radionuclides dissolve in water and first transport into plants and then transport from plants to humans. In the latest years, artificial fertilizing has replaced natural fertilizing in agriculture. Therefore, fruits and vegetables contain radionuclides those are found in artificial fertilizers. In this study, electrochemical deposition technique with alpha counting method was used for determining the radioactivity level of polonium in fertilizers. Radium, potassium and thorium concentrations were measured by gamma spectrometry. TSP, MAP, DSP,MKP, (15-15-15), (18-18-18), (20-20-20) compost fertilizers consumed at most has been analyzed and the results were evaluated with respect to human health

[en] The manual of inorganic solid fertilizers of Costa Rica presents as first the description of some nutritious characteristics of the main ones, such as functions, content, forms, symptoms of deficiency among others. Some of the chemical physical characteristics of the included materials were used as prime materials. There is also in the Manual a listing of the main sources fertilizers used in Costa Rica, as well as the main processes of production of fertilizers, while they are considered several listings with the products that the different commercial houses have to disposition of the publish. Finally a summary of the imports of fertilizers is made in Costa Rica during the years 1998, 1999 and 2000, to finish with the general listing of all the products fertilizers registered in Costa Rica, under the order N-P₂O₅-K₂O. (Author)

[en] Land salinization is one of the major desertification processes in Pakistan. Salinization occurs both naturally and as a result of human activities. Salinity has very adverse social, economic and health problems. Field studies were carried out to quantify the impact of addition of potassium chloride [muriate of potash (MOP)] fertilize on the accumulation and distribution of chloride in the soil profile. The treatments were consisted of 0, 57, 114 and 228 kg Cl ha/sup -1/ in form of MOP fertilizer. Cotton crop was used as test crop. The total quantity of applied irrigation water and total precipitation was 2581 m/sup 3/ ha/sup -1/ and 86 mm, respectively. Results showed that application of 228 kg Cl ha/sup -1/ raised the level of Cr from 4.9 to 7.2 meq L/sup -1/ in the upper 0-30 cm soil profile. Chloride content was higher at lower depths because of addition of 57 to 228 kg Cl ha/sup -l/ in the form of MOP. The addition K-fertilizer in the form of MOP raised the level of Cl content by 76.5 percent over added of the same quantity in the form of potassium sulphate [sulphate of potash (SOP)]. These studies show that continuous application of MOP would lead to accumulation of Cl in the soils. This is more particularly in the arid environment of Multan, where rainfall is scanty and insufficient to leach down Cl to the lower soil horizons. (author)

[en] Present article is devoted to study of nitrogen influence on potato yield. The potato belongs to number of the major agricultural crops and has specific requirements for root nutrition. This important biological feature causes a weak root system. For normal growth, development and yield accumulation potatoes needs more nutrients. High yields of potatoes prepared by introducing organic and mineral fertilizers. Application of the increased doses of nitrogen fertilizers leads to powerful development of aboveground mass. (author)

[en] A field experiment was conducted on sandy loam soil at IARI farm, New Delhi to evaluate the effect of FYM and sulphur on fertilizer N utilisation by wheat. The experiment was laid down in a randomized block design with three replications at three levels of substitution of recommended N by FYM, 50, 25 and 0 percent and three levels of sulphur 0, 20 and 40 kg S ha^-1 to wheat. Twenty five percent substituted N through FYM recorded highest grain yield. Sulphur application resulted in 2-6 percent increase in yield, fertilizer N utilization ranged from 33 to 45.7 percent and fertilizer N recovery was 66 to 94.5 percent. Higher fertilizer N recovery was associated wth lower rate of fertilizer N application. FYM and S application increased fertilizer N recovery in wheat by 12-22 percent and 2-9 percent, respectively. (author)

[en] Low cost and effective agriculture inputs are essential for sustainable agriculture production. Biofertilizer and liquid low molecular weight chitosan (LMC), otherwise well known as oligochitosan, produced from natural resources are alternatives to reduce dependency on chemical fertilizers and chemical based pesticides and pest repellents. Previous studies showed combination of biofertilizer and LMC enhanced productivity. Normal practices were to apply biofertilizer and LMC separately. These practices were labour intensive and time costing. Biofertilizer contains living microorganisms, and thus there was a concern on deleterious effect when oligochitosan was applied together with biofertilizer. The objective of the present study is to determine survival and shelf life of a biofertilizer microorganism in mixture with LMC. Acinetobacter baumannii (AP1) is a multifunctional biofertilizer bacterium with nitrogen (N₂) fixation, phosphate solubilisation and potassium solubilisation capabilities. AP1 was mixed with LMC. The mixtures were kept at room and cool temperature. The population of AP1 was determined monthly by serial dilution method. Results showed survival and shelf life of AP1 were good even after two months storage at room and cool temperature. The study will continue for up to six-month storage. (author)

[en] To evaluate the use of compost and natural rocks as partial replacement of mineral fertilizers in ‘Flame’ seedless grape vineyards. The present work was conducted during three successive seasons (2016, 2017 and 2018), being the first season a preliminary trial on 4-yr old grapes cultivated in two different soil types (sandy and clay) at two different locations, Egypt (Abo Galeb, Giza governorate; EL-Mahala, Gharbia governorate). Treatments were applied as natural raw materials at 20, 40, 60, 80 and 100% out of recommended mineral NPK rate. The mineral fertilizers used were ammonium sulfate (21.6% N), calcium super phosphate (15.5% P2O5) and potassium sulfate (48% K2O). The natural rocks used were phosphate rock (22.0% P2O5) and Feldspar (10.12% K2O). Yield and fruit characteristics and leaf mineral content were determined.Using compost in combination with natural rocks enriched with NPK mobilization bacteria and mineral NPK enhanced leaf nutrients content and gave the highest yield and cluster weight. This mix also improved berries physical and chemical characteristics. There was an increase in soluble solids content (SSC), SSC/acid ratio, and anthocyanin content, associated with a reduction in nitrate content of the berry juice. The most pronounced effect was related to using 60% mineral fertilization + 40% organic and natural rocks in both vineyard locations.

[en] Various approaches have been utilized in attempting to cryopreserve oocytes, beginning with slow cooling and more recently the advent of technique of vitrification. Now it seems that oocyte cryopreservation is no longer an experimental technique and it is being increasingly utilized in clinics around the world. As successful outcome in oocyte cryopreservation can be assessed by survival through the freeze-thaw process, potential for fertilization, embryo development and dynamics of meiotic spindles. This study aimed to analyse these features in context of vitrification and slow freezing. Methods: In this laboratory based study, mature MII mouse oocytes from F1(C57BL6/J X CBA) mice (n=43) were divided randomly into two groups of equal numbers and were cryopreserved by slow freezing and by vitrification. Upon re-warming these oocytes were assessed for survival and for fertilization potential. Oocytes were fixed and stained to compare the effect of both protocols on spindle reassembly and chromosome configuration 10min, 1h and 3h after warming. Unfrozen oocytes were used as controls. Results: A greater number of vitrified oocytes survived cryopreservation than slow frozen oocytes (70.3% vs. 12.5%, p=0.024). After insemination, fertilization rates were higher for vitrified oocytes as compared to slow frozen oocytes (15.86% vs. 4.6%, p=0.046). Morphology of the meiotic spindle was found to be in a disorganized configuration in slow frozen oocytes at all-time points 10 mins, 1 h and 3h), whereas in vitrified oocytes the spindles were found to be aligned at all-time points. Chromosomes were seen to be displaced from equatorial region in both groups. Conclusion: Cryopreservation of mouse oocytes was conducted with greater success using vitrification, compared to slow freezing, with survival, fertilization, and spindle assembly more favourable to a successful outcome in this model. (author)