جستجوی مقالات مرتبط با کلیدواژه "nutrition management" در نشریات گروه "کشاورزی"

Root-knot nematodes (Meloidogyne spp.) are serious pathogens in pistachio orchards and nurseries. Unfortunately, in most orchards, regular monitoring and correct use of integrated nematode management methods are not done. Nematode damage, along with the salinity and alkalinity of the soil in most pistachio orchards and unprincipled fertilization, has caused a significant decrease in pistachio production per hectare. Chemical nematicides for control lead to environmental pollution and seriously threaten human health. Therefore, finding low-risk methods to manage root-knot nematodes is a priority. Soil and bio solarization, soil amendments using organic fertilizers such as cow, poultry manure, and agricultural fermentation waste have shown convincing results. Following the observation of different levels of nematode control using mineral and chemical fertilizers, the present study was designed. So, the effect of different sulfur concentrations and application time on the control of root-knot nematode, Meloidogyne javanica, and its effect on growth factors of pistachio plants was surveyed.

The experimental treatments were different sulfur concentrations (zero, 50, 100, and 150 mg/kg of soil) and two application methods of sulfur (first time, simultaneous planting of pistachio seedlings with sulfur and nematode treatments and second time, planting of pistachio seedlings after 45 days of sulfur application and nematode inoculation) in four pistachio cultivars (Akbari, Qazvini, Badami Reez Zarand and Sefid Pistachio Nogh). The pure population of root-knot nematode was propagated on Solanum lycopersicum L. cv. Standard. The number of two second-stage juveniles was considered for inoculating each gram of soil. The pathogenicity indexes of nematode, including the number of second-stage juveniles per 300 grams of soil, the number of galls, and egg masses per gram of root, were calculated after two months of planting. Growth factors, including green leaf weight, fresh and dry weight of root and stem, root volume, stem and root length, stem diameter, and SPAD index, were also measured in all experimental treatments. The experiment was carried out in a factorial, completely randomized design with 12 replicates. SAS software version 9 was used for data analysis. Means were compared using Duncan's test.

A low population of second-stage juveniles was observed in all cultivars at 50 mg/kg sulfur concentration. A significant decrease in gall and egg mass indexes were observed at the second time compared to the first sulfur application. Except for the Akbari cultivar, the nematode reproduction factor showed a significant reduction at 50 mg/kg. In the absence of nematodes in the Akbari cultivar, the concentration of 150 mg/kg of sulfur increased the stem fresh weight by 40% compared to the control. Regardless of the concentration, the first time showed better results on the SPAD in three Akbari, Qazvini, and Badami cultivars. In the presence of nematode and the second time, the concentration of 50 mg/kg of sulfur for the Qazvini cultivar caused a 68% increase in the stem fresh weight, 32% in the stem length, and 22% in the stem diameter and the same conditions, for Qazvini and Sefid Pistachio Nogh, had the greatest effect on the leaf weight. The concentration of 50 mg/kg of sulfur and the second time for Qazvini and Sefid pistachio Nogh cultivars had the highest effect on the green leaf weight compared to the control in the presence of nematodes.

In this research, apart from the Akbari cultivar, the largest decrease was observed in the soil covered with plastic in three other cultivars. According to the results of this research, using a concentration of 50 mg/kg of sulfur, covering the soil surface, and planting pistachio seeds after 45 days can significantly reduce the root-knot nematode population. This finding can be used in pistachio nurseries. For further studies, it is suggested to use sulfur fertilizers and their mixture with biological agents compatible with salty and alkaline soils of pistachio planting areas to reduce the population of root-knot nematodes.

The global approach in agricultural production is to increase the quantitative and qualitative yield of plants through management methods such as the use of organic fertilizers and reducing the use of chemical fertilizers. This experiment was conducted as a split factorial arrangement with three replications in two folds in Bandarabbas during 2018 and 2019. The main factor included irrigation intervals at three levels (irrigation 80, 60, and 40% of field capacity) and the subfactor was different fertilizer sources at three levels (poultry manure, sheep manure, and chemical fertilizer based on the results of soil and plant test) and different species of Atriplex (A. canascens, A. leucoclada and A. lentiformis). The results showed that increasing drought stress increased ion and malondialdehyde leakage and decreased relative leaf water content and leaf chlorophyll content of Atriplex. In irrigation of 60 and 40% of field capacity, the use of poultry and sheep manures reduced ion and malondialdehyde leakage of leaves. At 40% of field capacity, plant height in poultry and sheep manures increased by 28% and 38% compared to chemical fertilizer. Also, in 40% of field capacity, biological yield in poultry and sheep manures compared to chemical fertilizer showed a 4 and 8% increase. Increasing the total phenol content in sheep manures compared to chemical fertilizer in irrigation was 40% of field capacity. Overall, the results showed that the use of organic fertilizers by improving physiological traits to some extent increased the resistance to drought stress. Also, in drought stress conditions, organic fertilizers were more effective than chemical fertilizers. In general, based on the findings of this research, it can be concluded that the use of organic fertilizers in order to provide all or part of the nutritional needs of Atriplex maintains the optimal yield of Atriplex plants under water stress conditions.

For investigation the effect of algae extracts and mother corm weights on flower yield and growth characteristics of saffron (Crocus sativus L.), an experiment was conducted at Research Farm of College of Agricultural, University of Birjand, during 2017. The factors included three seaweed extracts (0, 15 and 30 L ha-1) and three corm weights [0.1- 4 (small), 4.1 – 8 (medium) and 8.1 - 12g (large-sized)] which were tested in a RCBD with three replications. Application of algae extract had a significant effect on flower yield, stigma yield, leaf weight and chlorophyll a content. The highest flower yield (1.29 g.m-2), dry stigma yield (0.059 g.m-2), leaf dry weight (0.092 g per plant) and chlorophyll a (11.1 mg g-1 FW) were obtained at 30 L ha-1 of algae extract, while the lowest amounts of flower yield (1.061 g m-2), stigmas yield (0.052 g m-2), leaves weight (0.076 g per plant) and chlorophyll a (0.98 g-1 FW) were gained in the control treatment. However, no significant difference was found between the levels 15 and 30 L ha-1 of algae extract. Corm weight also significantly influenced all studied traits. The highest number of flowers (4.7 per m-2), stigma length (33.6 mm), number of leaves (9.3 per plant) and leaf length (33.6 cm) were found in large corms, but the smallest of them were obtained from small ones. Based on the results of the interaction effects of experimental factors, the highest chlorophyll b and total chlorophyll (1.79 and 2.98 mg g-1 FW, respectively) were obtained from 30 L ha-1 of algae extract and large corms. Overall, the use of organic algae extract (30 L ha-1) and planting of larger mother corms significantly improved the growth and stigma yield of saffron.

In order to evaluate the effect of humic acid and complete micronutrient fertilizer on growth and economic performance of different bread wheat cultivars, a factorial experiment was conducted on the base of randomized complete block design with three replications in Biranshahr region (Lorestan province) during two years in 2015-16 and 2016-17. The main factors included nutrition at four levels (control, humic acid, complete fertilizer 20-20-20 and humic acid + complete fertilizer 20-20-20) and bread wheat cultivars as sub-factors included (Mihan, Sivand and Alvand). The results showed that the number of spikes per square meter, number of seeds per spike, 1000-seed weight, biological yield, and grain yield and harvest index of wheat cultivars were influenced by the studied factors. The highest economic yield (8296 kg/ha) was obtained in the treatment of humic acid application + complete micronutrient fertilizer in Alvand cultivar. The highest number of spikes per m2 was related to humic acid feeding treatment in Alvand cultivar with an average of 625 spikes per m2. The highest number of seeds per spike was obtained in the treatment with humic acid feeding along with complete fertilizer in Alvand cultivar with an average of 45.2. The highest 1000-seed weight was related to feeding with humic acid + complete fertilizer with an average of 42.0 g. Interaction of humic acid with complete fertilizer in Alvand cultivar has produced the highest biological yield (19156 kg/ha). The highest harvest index (43.6%) was observed in complete fertilizer feeding treatment in Alvand cultivar. Findings showed that the application of humic acid along with chemical fertilizers increases the quality and quantity of agricultural products and maintains the balance of the environment.

Evaluation of the nutrient status in soil is important from the nutritional, environmental, and economical aspects. Potassium is an essential element for plant growth and is a dynamic ion in the soil system. Soil testing is a useful tool that can help to ensure the efficient use of applied plant nutrients. Soil tests measure the quantity of a nutrient element that is extracted from a soil by a particular chemi¬cal extracting solution. The measured quantity of extractable nutrient in soil is then used to predict the crop yield response to application of the nutri¬ent as fertilizer, manure, or other amendments. Over the years, many different soil testing pro¬cedures and extracting solutions were evaluated in an effort to identify a method that provides the most reliable prediction of crop yield response to nutrient application. It was determined that some soil testing procedures are best suited for particular soil types and climatic regions, whereas other soil testing procedures are better suited for different soil types and climates. Olive is a strategic and economic product in Iran. Fars province is the second largest olive producer in Iran. There is no general information about K status in the soils and olive trees of the Fars province as well as no introduced appropriate K extractants for theses soils. Therefore, the objectives of this study were: i) evaluating potassium status of some soils of olive orchards of Fars province and ii) introducing appropriate k extractants for extracting available K in these soils.
Fars province, with an area of 122000 km2 is located in southern Iran. The elevation varies from 500 m to 4400 m above mean sea level. Based on the information regarding olive orchards of Fars province, 13 typical olive orchards were selected. 26 surface (0-30 cm) and subsurface (30-60 cm) soil samples were taken. Physiochemical properties of the soil samples were determined based on standard methods. Soil reaction, texture, electrical conductivity, calcium carbonate, organic carbon, and cation exchange capacity were identified. The 12 K extracting solutions were 1M NaCl, 2M NaCl, 0.01M CaCl2, Morgan, AB-DTPA, 1M NH4OAC, 0.25M NH4OAC, 1M NaOAC, 2M HCl, 0.1M HNO3, 1M HNO3, and 0.025M H2SO4. The K contents of leaf samples were determined in 1g of each sample. The samples were dried and then ashed in 450°C for 4 h. 2M HCl was used to digest the samples. Potassium in all the filtrated extracts were then analyzed using flame photometer.
The all soils were calcareous (average of 48.7 and 50.2% calcium carbonate equivalent in surface and subsurface, respectively) with pH in range of 7.05-7.8. The textural classes were loam, clay loam, and sandy loam. The results showed that the concentrations of K extracted varied widely with the used method, because each extractant remove different portions of K. Among the 12 tested methods, boiling 1 mol/L HNO3 extracted highest amount of K (mean 696.1 mg/kg and range of 203.3-1893 mg/kg) which extracted soluble, exchangeable, and non-exchangeable potassium forms due to its high concentration of H and 2mol/L HCl removed the lowest amount of K (mean 32.7 mg/kg and range of 2.6-148.5 mg/kg). Correlation coefficients between K extracted by 12 extractants were de¬termined. The correlation between potassium extracted by all the chemical methods was positive and significant except for boiling 1M HNO3. Between all tested extractants, 0.25M NH4OAC and 1M NH4OAC had the highest correlation (p≤0.01, r= 0.999). The relationship between soil potassium and potassium concentration in olive leaves were evaluated. Maximum correlation between leaf K and extracted soil K were noticed in 2M NaCl, 0.25M NH4OAC, 1M NaOAC, and AB-DTPA (r=0.721, 0.718, 0.717, and 0.714, respectively) and the minimum correlation was noticed in 1M HNO3 (r= 0.661).
The concentrations of K extracted varied widely with applied method, because of desorbing different portions of K by each method, different concentrations of each extracting solution, and the different times of equilibration. On average, the quantity of extracted K by 12 methods were in the following order: boiling 1M HNO3> 1M NH4OAC> 0.25M NH4OAC> AB-DTPA> morgan> 0.1 HNO3> 0.025M H2SO4> 0.01M CaCl2> 1M NaCl> 1M NaOAC> 2M NaCl> 2M HCl. This study showed that 2M NaCl, 0.25M NH4OAC and 1M NaOAC would be suitable as soil testing methods for determining available K for olive in the soils of Fars province. These extractants were the best because of high correla¬tion with plants potassium. In addition, advantages of these extractants are low cost and simplicity. As a recommendation, using of K fertilizers in most olive orchards of the province will improve quantity and quality of the yield.

An investigation was carried out to evaluate growth performance and carcass characteristics of three commercial broiler strain ( A, B, C ), during four husbandry period in randomized complete block design with three treatment include stains and four block based on nutrition program include four phasing diets, high energy and high protein diets, pellet from diets and low energy and low protein diets. Husbandry conditions including environmental and managmental factors, were the same for three strains during each experimental periods.
The traits under consideration were daily body weight gain, daily feed intake, feed conversion ratio, means of live body weight, index of production, livability, carcass percentage, percent of breast, thigh and abdominal fat in end of 42th days of age. Statistical analysis of performance criteria showed that difference of daily weight gain in 42 days among of strain was significant and B had highest and C had lowest means of daily weight gain (P

This research was performed to investigate status of nutrition management of industrial dairy farms in Varamin and Pishva. List, statistics and location information on industrial dairy farms were first obtained from data present at livestock affair effect of agricultural Jihad of the foresaid cities. From 27 to 100 percent of active farms, a total of 43 dairy units was selected. The selected farms were classified into six groups in terms of productive cow capacity: (10-50), (51-150), (151-300), (301-450), (451600) and (601-1800). Totally 12986 dairy cows were assessed since shahrivar of 1390 until Esfand of 1391 using questionnaire either verbally or direct data collection. In order to facilitate investigation cows were classified into high-productive, midproductive, low productive and dry cows.Mean food consumption based on dry matter consumed (kg), lactating net energy (mega calorie), crude protein, Ca and P (g) for high-productive, mid-productive, low- productive and dry cows were equaled to (3/686, -1/919, 0/251, -1/919), (27/408, 29/114, 27/038), (0/686, -1/485, -1/357, 1/109), (0/089, 0/090, 0/094, 0/089) and (0/081, 0/0093, 0/0137, 0/073) respectively, Mean dry matter consumption for high productive and dry cows was different at probability levels of 0/05 and lactating net energy for all groups was different at p